JP4605943B2 - Cogeneration system operation method - Google Patents

Description

ここで、Ｓ［ｔ＋（ｎ−１）ｄ］は各分割時間の運転開始時の蓄熱タンク内の蓄熱量を示している。また、ｎは、１〜Ｔ／ｄの正の整数であり、ｈ（ｔ’）は、予め特定された熱需要の経時的変化を示す関数であり、ｅｘ（ｔ’）はシステムからの放熱量である。Ｓ_max は、蓄熱タンクの最大蓄熱量を示している。
ＨＴ_n は分割時間間隔ｄ内での取得熱量を示し、下記（２）式で表される。
【数３１】

ここで、Ｆは定格発電量の電力を、ｋは熱電比をそれぞれ示している。また、Ｈ_nは余剰電力を電熱変換手段で熱に変換した変換熱量で、Ｆ＞Ｅ_n （ｔ’）の分を積算するものであり、下記（３）式で表される。
【数３２】

但し、ｅ（ｔ’）＜Ｆであれば、Ｅ_n （ｔ’）＝ｅ（ｔ’）
ｅ（ｔ’）≧Ｆであれば、Ｅ_n （ｔ’）＝Ｆ
ここで、Ｅ_n （ｔ’）は、負荷電力が定格発電量の電力を越える場合は定格電力量となり、負荷電力が定格電力より小さい場合はその負荷電力量となる電力量であり、ｅ（ｔ’）は、予め特定された電力需要（負荷電力）の経時的変化を示す関数である。
上記（２）式において、ＢＯ（ｔ’）は、熱量不足を生じた際に、その不足分を補うように補助加熱手段を起動する場合の関数を示している。
ＰＥ＝ΣＰＥ_n ＝ΣＧＩ_n ・α＋ΣＢＩ_n ・α’＋ΣＢＥ_n ・β……（４）
ここで、ΣＰＥ_n は、ｎ＝１〜Ｔ／ｄの一次エネルギーの総和である。ＧＩ_nは熱電併給装置の運転に要する燃料供給量であり、次式（５）で表され、また、αは燃料の一次エネルギーへの換算値であり、ΣＧＩ_n ・αはｎ＝１〜Ｔ／ｄの総和を求めている。また、ＢＩ_n は補助加熱手段の運転に要する燃料供給量であり、α’は燃料の一次エネルギーへの換算値であり、ΣＢＩ_n ・α’はｎ＝１〜Ｔ／ｄの総和を求めている。
【数３３】

ここで、ＧＩ（ｔ’）は、使用する熱電併給装置によって特定される燃料供給量である。
ΣＢＥ_n は、１周期Ｔとなる所定時間Ｔ内での不足分の電力の投入量であり、次式（６）で表され、また、βは電力の一次エネルギーへの換算値であり、ｎ＝１〜Ｔ／ｄの総和を求めている。
【数３４】

ここで、ＧＰは、熱電併給装置の発電量であり、次式（７）で表される。
【数３５】

ここで、Ｅ（ｔ’）は、負荷電力が定格発電量の電力を越える場合は定格電力量となり、負荷電力が定格電力より小さい場合はその負荷電力量となる電力量である。
【００１０】
また、請求項３に係る発明のコージェネレーションシステムの運転方法は、前述のような目的を達成するために、
負荷電力が定格発電量より少ない場合に負荷電力に合わせて運転することができる電力と熱とを発生する熱電併給装置と、
前記熱電併給装置で発生した熱を貯める蓄熱タンクと、
不足分の熱量を補う補助加熱手段と、
所定時間を１周期として、その１周期内の熱需要および電力需要それぞれの経時的変化を予め特定する需要変化特定手段と、
不足分の電力を投入可能な買電手段とを備え、
前記１周期内での熱需要分に相当する量の熱を前記熱電併給装置により前記１周期内で発生させて消費するとともに、余剰となった熱を次の周期で消費することを許容し、かつ、不足分の熱量を前記補助加熱手段で補い、前記１周期を設定時間間隔ごとに分割して、各分割時間それぞれにおいて前記熱電併給装置を運転する状態と停止する状態とを想定し、前記蓄熱タンク内の蓄熱量が０以上でかつ最大蓄熱量を越えないようにして、全体の一次エネルギーの換算値が最小となる組み合わせの最適運転状態を求め、求められた最適運転状態によって、前記熱電併給装置を定格発電量で運転するとともに電力需要が定格発電量の電力よりも小さいときには電力需要の変化に追従させて運転することを特徴としている。
また、請求項４に係る発明のコージェネレーションシステムの運転方法は、前述のような目的を達成するために、
所定時間を１周期Ｔとして、その１周期Ｔ内の熱需要および電力需要それぞれの経時的変化を予め特定する需要変化特定手段を備え、
前記１周期Ｔ内での熱需要分に相当する量の熱を前記熱電併給装置により前記１周期Ｔ内で発生させて消費するとともに、余剰となった熱を次の周期で消費することを許容し、かつ、不足分の熱量を前記補助加熱手段で補い、前記１周期Ｔを設定時間間隔ｄごとに分割して、各分割時間それぞれにおいて前記熱電併給装置を運転する状態と停止する状態とを想定し、前記蓄熱タンク内の蓄熱量の変動値Ｓ（ｔ＋ｎ・ｄ）が常に下記条件式（８）を満たすとともに、下記一次エネルギーの換算値ＰＥ［式（１０）］が最小となる組み合わせの最適運転状態を求め、求められた最適運転状態によって、前記熱電併給装置を定格発電量で運転するとともに電力需要が定格発電量の電力よりも小さいときには電力需要の変化に追従させて運転することを特徴としている。
【数３６】

ここで、Ｓ［ｔ＋（ｎ−１）ｄ］は各分割時間の運転開始時の蓄熱タンク内の蓄熱量を示している。また、ｎは、１〜Ｔ／ｄの正の整数であり、ｈ（ｔ’）は、予め特定された熱需要の経時的変化を示す関数であり、ｅｘ（ｔ’）はシステムからの放熱量である。Ｓmax は、蓄熱タンクの最大蓄熱量を示している。
ＨＴn は分割時間間隔ｄ内での取得熱量を示し、下記（９）式で表される。
【数３７】

ここで、Ｅn （ｔ’）は、負荷電力が定格発電量の電力を越える場合は定格電力量となり、負荷電力が定格電力より小さい場合はその負荷電力量となる電力量である。Ｂ［Ｅn （ｔ’）］は、電力量Ｅn （ｔ’）における熱電併給装置の発生熱量を示している。
また、ＢＯ（ｔ’）は、熱量不足を生じた際に、その不足分を補うように補助加熱手段を起動する場合の関数を示している。
ＰＥ＝ΣＰＥn ＝ΣＧＩn ・α＋ΣＢＩn ・α’＋ΣＢＥn ・β……（１０） ここで、ΣＰＥn は、ｎ＝１〜Ｔ／ｄの一次エネルギーの総和である。ＧＩnは熱電併給装置の運転に要する燃料供給量であり、次式（５ａ）で表され、また、αは燃料の一次エネルギーへの換算値であり、ΣＧＩn ・αはｎ＝１〜Ｔ／ｄの総和を求めている。また、ＢＩn は補助加熱手段の運転に要する燃料供給量であり、α’は燃料の一次エネルギーへの換算値であり、ΣＢＩn ・α’はｎ＝１〜Ｔ／ｄの総和を求めている。
【数３８】

ここで、ＧＩ（ｔ’）は、使用する熱電併給装置によって特定される燃料供給量である。
ΣＢＥn は、１周期Ｔとなる所定時間Ｔ内での不足分の電力の投入量であり、次式（１１）で表され、また、βは電力の一次エネルギーへの換算値であり、ｎ＝１〜Ｔ／ｄの総和を求めている。
【数３９】

ここで、ＧＰは、熱電併給装置の発電量であり、次式（１２）で表される。
【数４０】

ここで、Ｅ（ｔ’）は、負荷電力が定格発電量の電力を越える場合は定格電力量となり、負荷電力が定格電力より小さい場合はその負荷電力量となる電力量であり、ｅ（ｔ’）は、予め特定された電力需要（負荷電力）の経時的変化を示す関数である。
【００１１】
また、請求項５に係る発明のコージェネレーションシステムの運転方法は、前述のような目的を達成するために、
複数段に設定した発電量で運転して設定発電量の電力と熱とを発生する熱電併給装置と、
前記熱電併給装置で発生した熱を貯める蓄熱タンクと、
前記熱電併給装置で発生した電力を熱に変換する電熱変換手段と、
不足分の熱量を補う補助加熱手段と、
所定時間を１周期として、その１周期および次の１周期それぞれ内の熱需要および電力需要それぞれの経時的変化を予め特定する需要変化特定手段と、
不足分の電力を投入可能な買電手段とを備え、
前記１周期内での熱需要分に相当する量の熱を前記熱電併給装置により前記１周期内で発生させて消費するとともに、余剰となった熱を次の周期で消費することを許容し、かつ、不足分の熱量を前記補助加熱手段で補い、前記１周期を設定時間間隔ごとに分割して、各分割時間それぞれにおいて前記熱電併給装置を複数段の設定発電量それぞれで運転する状態と停止する状態とを想定し、前記蓄熱タンク内の蓄熱量が０以上でかつ最大蓄熱量を越えないようにして、全体の一次エネルギーの換算値が最小となる組み合わせの最適運転状態を求め、求められた最適運転状態によって、前記熱電併給装置を複数段の定格発電量で運転するとともに電力需要が設定発電量よりも小さいときの余剰電力を前記電熱変換手段で熱に変換することを特徴としている。
また、請求項６に係る発明のコージェネレーションシステムの運転方法は、前述のような目的を達成するために、
請求項５に記載のコージェネレーションシステムの運転方法において、
所定時間を１周期Ｔとして、その１周期Ｔおよび次の１周期Ｔそれぞれ内の熱需要および電力需要それぞれの経時的変化を予め特定する需要変化特定手段を備え、
複数段に設定した発電量で運転して設定発電量の電力と熱とを発生する熱電併給装置と、
前記熱電併給装置で発生した熱を貯める蓄熱タンクと、
前記熱電併給装置で発生した電力を熱に変換する電熱変換手段と、
不足分の熱量を補う補助加熱手段と、
所定時間を１周期Ｔとして、その１周期Ｔおよび次の１周期Ｔそれぞれ内の熱需要および電力需要それぞれの経時的変化を予め特定する需要変化特定手段と、 不足分の電力を投入可能な買電手段とを備え、
前記１周期Ｔ内での熱需要分に相当する量の熱を前記熱電併給装置により前記１周期Ｔ内で発生させて消費するとともに、余剰となった熱を次の周期で消費することを許容し、かつ、不足分の熱量を前記補助加熱手段で補い、前記１周期Ｔを設定時間間隔ｄごとに分割して、各分割時間それぞれにおいて前記熱電併給装置を複数段の設定発電量それぞれで運転する状態と停止する状態とを想定し、前記蓄熱タンク内の蓄熱量の変動値Ｓ（ｔ＋ｎ・ｄ）が常に下記条件式（１３）を満たすとともに、下記一次エネルギーの換算値ＰＥ［式（１６）］が最小となる組み合わせの最適運転状態を求め、求められた最適運転状態によって、前記熱電併給装置を複数段の定格発電量で運転するとともに電力需要が設定発電量よりも小さいときの余剰電力を前記電熱変換手段で熱に変換することを特徴としている。
【数４１】

ここで、Ｓ［ｔ＋（ｎ−１）ｄ］は各分割時間の運転開始時の蓄熱タンク内の蓄熱量を示している。また、ｎは、１〜Ｔ／ｄの正の整数であり、ｈ（ｔ’）は、予め特定された熱需要の経時的変化を示す関数であり、ｅｘ（ｔ’）はシステムからの放熱量である。Ｓ_max は、蓄熱タンクの最大蓄熱量を示している。
ＨＴ_n は分割時間間隔ｄ内での取得熱量を示し、下記（１４）式で表される。
【数４２】

ここで、Ｆ_m は設定発電量を、ｋ_m は設定発電量Ｆ_m での熱電比をそれぞれ示している。ｍは、２以上で発電量の設定段数までの正の整数である。また、Ｈ_nは余剰電力を電熱変換手段で熱に変換した変換熱量で、Ｆ_m ＞Ｅ_n （ｔ’）の分を積算するものであり、下記（１５）式で表される。
【数４３】

但し、ｅ（ｔ’）＜Ｆ_m であれば、Ｅ_n （ｔ’）＝ｅ（ｔ’）
ｅ（ｔ’）≧Ｆ_m であれば、Ｅ_n （ｔ’）＝Ｆ_m
ここで、Ｅ_n （ｔ’）は、負荷電力が設定発電量Ｆ_m を越える場合は設定電力量となり、負荷電力が設定発電量Ｆ_m より小さい場合はその負荷電力量となる電力量であり、ｅ（ｔ’）は、予め特定された電力需要（負荷電力）の経時的変化を示す関数である。
上記（１４）式において、ＢＯ（ｔ’）は、熱量不足を生じた際に、その不足分を補うように補助加熱手段を起動する場合の関数を示している。
ＰＥ＝ΣＰＥ_n ＝ΣＧＩ_n ・α＋ΣＢＩ_n ・α’＋ΣＢＥ_n ・β……（１６）
ここで、ΣＰＥ_n は、ｎ＝１〜Ｔ／ｄの一次エネルギーの総和である。ＧＩ_nは熱電併給装置の運転に要する燃料供給量であり、次式（１７）で表され、また、αは燃料の一次エネルギーへの換算値であり、ΣＧＩ_n ・αはｎ＝１〜Ｔ／ｄの総和を求めている。また、ＢＩ_n は補助加熱手段の運転に要する燃料供給量であり、α’は燃料の一次エネルギーへの換算値であり、ΣＢＩ_n ・α’はｎ＝１〜Ｔ／ｄの総和を求めている。
【数４４】

ここで、ＧＩ（ｔ’）は、使用する熱電併給装置によって特定される燃料供給量である。
ΣＢＥ_n は、１周期Ｔとなる所定時間Ｔ内での不足分の電力の投入量であり、次式（１８）で表され、また、βは電力の一次エネルギーへの換算値であり、ｎ＝１〜Ｔ／ｄの総和を求めている。
【数４５】

ここで、ＧＰは、熱電併給装置の発電量であり、次式（１９）で表される。
【数４６】

ここで、Ｅ（ｔ’）は、負荷電力が設定発電量Ｆm を越える場合は設定電力量となり、負荷電力が設定発電量Ｆ_m より小さい場合はその負荷電力量となる電力量である。
【００１２】
また、請求項７に係る発明のコージェネレーションシステムの運転方法は、前述のような目的を達成するために、
定格発電量の電力と熱とを発生する熱電併給装置と、
前記熱電併給装置で発生した熱を貯める蓄熱タンクと、
前記熱電併給装置で発生した電力を第３者に売る売電手段と、
不足分の熱量を補う補助加熱手段と、
所定時間を１周期として、その１周期内の熱需要および電力需要それぞれの経時的変化を予め特定する需要変化特定手段と、
不足分の電力を投入可能な買電手段とを備え、
前記１周期内での熱需要分またはその大半に相当する量の熱を前記熱電併給装置により前記１周期内で発生させて消費するとともに、余剰となった熱を次の周期で消費することを許容し、かつ、不足分の熱量を前記補助加熱手段で補い、前記１周期を設定時間間隔ごとに分割して、各分割時間それぞれにおいて前記熱電併給装置を運転する状態と停止する状態とを想定し、前記蓄熱タンク内の蓄熱量の変動値が０以上でかつ最大蓄熱量を越えないようにして、全体の一次エネルギーの換算値が最小となる組み合わせの最適運転状態を求め、求められた最適運転状態によって、前記熱電併給装置を定格発電量で運転するとともに電力需要が定格発電量の電力よりも小さいときの余剰電力を前記売電手段で第３者に売ることを特徴としている。
また、請求項８に係る発明のコージェネレーションシステムの運転方法は、前述のような目的を達成するために、
所定時間を１周期Ｔとして、その１周期Ｔ内の熱需要および電力需要それぞれの経時的変化を予め特定する需要変化特定手段を備え、
前記１周期Ｔ内での熱需要分またはその大半に相当する量の熱を前記熱電併給装置により前記１周期Ｔ内で発生させて消費するとともに、余剰となった熱を次の周期で消費することを許容し、かつ、不足分の熱量を前記補助加熱手段で補い、前記１周期Ｔを設定時間間隔ｄごとに分割して、各分割時間それぞれにおいて前記熱電併給装置を運転する状態と停止する状態とを想定し、前記蓄熱タンク内の蓄熱量の変動値Ｓ（ｔ＋ｎ・ｄ）が常に下記条件式（２０）を満たすとともに、下記一次エネルギーの換算値ＰＥ［式（２２）］が最小となる組み合わせの最適運転状態を求め、求められた最適運転状態によって、前記熱電併給装置を定格発電量で運転するとともに電力需要が定格発電量の電力よりも小さいときの余剰電力を前記売電手段で第３者に売ることを特徴としている。
【数４７】

ここで、Ｓ［ｔ＋（ｎ−１）ｄ］は各分割時間の運転開始時の蓄熱タンク内の蓄熱量を示している。また、ｎは、１〜Ｔ／ｄの正の整数であり、ｈ（ｔ’）は、予め特定された熱需要の経時的変化を示す関数であり、ｅｘ（ｔ’）はシステムからの放熱量である。Ｓmax は、蓄熱タンクの最大蓄熱量を示している。
ＨＴn は分割時間間隔ｄ内での取得熱量を示し、下記（２１）式で表される。
【数４８】

ここで、Ｆは定格発電量の電力を、ｋは熱電比をそれぞれ示している。
上記（２１）式において、ＢＯ（ｔ’）は、熱量不足を生じた際に、その不足分を補うように補助加熱手段を起動する場合の関数を示している。
ＰＥ＝ΣＰＥn
＝ΣＧＩn ・α＋ΣＢＩn ・α’＋ΣＢＥn ・β−ΣＳＥn ・γ…（２２）
ここで、ΣＰＥn は、ｎ＝１〜Ｔ／ｄの一次エネルギーの総和である。ＧＩnは熱電併給装置の運転に要する燃料供給量であり、次式（２３）で表され、また、αは燃料の一次エネルギーへの換算値であり、ΣＧＩn ・αはｎ＝１〜Ｔ／ｄの総和を求めている。また、ＢＩn は補助加熱手段の運転に要する燃料供給量であり、α’は燃料の一次エネルギーへの換算値であり、ΣＢＩn ・α’はｎ＝１〜Ｔ／ｄの総和を求めている。
【数４９】

ここで、ＧＩ（ｔ’）は、使用する熱電併給装置によって特定される燃料供給量であり、運転停止状態では零となる。
ΣＢＥn は、１周期Ｔとなる所定時間Ｔ内での不足分の電力の投入量であり、次式（２４）で表され、また、βは電力の一次エネルギーへの換算値であり、ｎ＝１〜Ｔ／ｄの総和を求めている。
【数５０】

ここで、ＧＰは、熱電併給装置の発電量であり、次式（２５）で表される。
【数５１】

ここで、Ｅ（ｔ’）は、負荷電力が定格発電量の電力を越える場合は定格電力量となり、負荷電力が定格電力より小さい場合はその負荷電力量となる電力量である。また、ΣＳＥn は売電手段で第３者に売る余剰電力量で、Ｆ＞Ｅn （ｔ’）の分を積算するものであり、下記（２６）式で表され、また、γは第３者に売るときの価格分を一次エネルギーに換算した換算値であり、ｎ＝１〜Ｔ／ｄの総和を求めている。
【数５２】

但し、ｅ（ｔ’）＜Ｆであれば、Ｅn （ｔ’）＝ｅ（ｔ’）
ｅ（ｔ’）≧Ｆであれば、Ｅn （ｔ’）＝Ｆ
ここで、Ｅn （ｔ’）は、負荷電力が定格発電量の電力を越える場合は定格電力量となり、負荷電力が定格電力より小さい場合はその負荷電力量となる電力量であり、ｅ（ｔ’）は、予め特定された電力需要（負荷電力）の経時的変化を示す関数である。
【００１３】
また、請求項９に係る発明のコージェネレーションシステムの運転方法は、前述のような目的を達成するために、
複数段に設定した発電量で運転して設定発電量の電力と熱とを発生する熱電併給装置と、
前記熱電併給装置で発生した熱を貯める蓄熱タンクと、
前記熱電併給装置で発生した電力を第３者に売る売電手段と、
不足分の熱量を補う補助加熱手段と、
所定時間を１周期として、その１周期および次の１周期それぞれ内の熱需要および電力需要それぞれの経時的変化を予め特定する需要変化特定手段と、
不足分の電力を投入可能な買電手段とを備え、
前記１周期内での熱需要分に相当する量の熱を前記熱電併給装置により前記１周期内で発生させて消費するとともに、余剰となった熱を次の周期で消費することを許容し、かつ、不足分の熱量を前記補助加熱手段で補い、前記１周期を設定時間間隔ごとに分割して、各分割時間それぞれにおいて前記熱電併給装置を複数段の設定発電量それぞれで運転する状態と停止する状態とを想定し、前記蓄熱タンク内の蓄熱量が０以上でかつ最大蓄熱量を越えないようにして、全体の一次エネルギーの換算値が最小となる組み合わせの最適運転状態を求め、求められた最適運転状態によって、前記熱電併給装置を複数段の定格発電量で運転するとともに電力需要が設定発電量よりも小さいときの余剰電力を前記売電手段で第３者に売ることを特徴としている。
また、請求項１０に係る発明のコージェネレーションシステムの運転方法は、前述のような目的を達成するために、
所定時間を１周期Ｔとして、その１周期Ｔおよび次の１周期Ｔそれぞれ内の熱需要および電力需要それぞれの経時的変化を予め特定する需要変化特定手段を備え、
前記１周期Ｔ内での熱需要分に相当する量の熱を前記熱電併給装置により前記１周期Ｔ内で発生させて消費するとともに、余剰となった熱を次の周期で消費することを許容し、かつ、不足分の熱量を前記補助加熱手段で補い、前記１周期Ｔを設定時間間隔ｄごとに分割して、各分割時間それぞれにおいて前記熱電併給装置を複数段の設定発電量それぞれで運転する状態と停止する状態とを想定し、前記蓄熱タンク内の蓄熱量の変動値Ｓ（ｔ＋ｎ・ｄ）が常に下記条件式（２７）を満たすとともに、下記一次エネルギーの換算値ＰＥ［式（２９）］が最小となる組み合わせの最適運転状態を求め、求められた最適運転状態によって、前記熱電併給装置を複数段の定格発電量で運転するとともに電力需要が設定発電量よりも小さいときの余剰電力を前記売電手段で第３者に売ることを特徴としている。
【数５３】

ここで、Ｓ［ｔ＋（ｎ−１）ｄ］は各分割時間の運転開始時の蓄熱タンク内の蓄熱量を示している。また、ｎは、１〜Ｔ／ｄの正の整数であり、ｈ（ｔ’）は、予め特定された熱需要の経時的変化を示す関数であり、ｅｘ（ｔ’）はシステムからの放熱量である。Ｓ_max は、蓄熱タンクの最大蓄熱量を示している。
ＨＴ_n は分割時間間隔ｄ内での取得熱量を示し、下記（２８）式で表される。
【数５４】

ここで、Ｆ_m は設定発電量を、ｋ_m は設定発電量Ｆ_m での熱電比をそれぞれ示している。ｍは、２以上で発電量の設定段数までの正の整数である。
上記（２８）式において、ＢＯ（ｔ’）は、熱量不足を生じた際に、その不足分を補うように補助加熱手段を起動する場合の関数を示している。
ＰＥ＝ΣＰＥ_n
＝ΣＧＩ_n ・α＋ΣＢＩ_n ・α’＋ΣＢＥ_n ・β−ΣＳＥ_n ・γ…（２９）
ここで、ΣＰＥ_n は、ｎ＝１〜Ｔ／ｄの一次エネルギーの総和である。ＧＩ_nは熱電併給装置の運転に要する燃料供給量であり、次式（３０）で表され、また、αは燃料の一次エネルギーへの換算値であり、ΣＧＩ_n ・αはｎ＝１〜Ｔ／ｄの総和を求めている。また、ＢＩ_n は補助加熱手段の運転に要する燃料供給量であり、α’は燃料の一次エネルギーへの換算値であり、ΣＢＩ_n ・α’はｎ＝１〜Ｔ／ｄの総和を求めている。
【数５５】

ここで、ＧＩ（ｔ’）は、使用する熱電併給装置によって特定される燃料供給量であり、運転停止状態では零となる。
ΣＢＥ_n は、１周期Ｔとなる所定時間Ｔ内での不足分の電力の投入量であり、次式（３１）で表され、また、βは電力の一次エネルギーへの換算値であり、ｎ＝１〜Ｔ／ｄの総和を求めている。
【数５６】

ここで、ＧＰは、熱電併給装置の発電量であり、次式（３２）で表される。
【数５７】

ここで、Ｅ（ｔ’）は、負荷電力が定格発電量の電力を越える場合は定格電力量となり、負荷電力が定格電力より小さい場合はその負荷電力量となる電力量である。また、ΣＳＥ_n は売電手段で第３者に売る余剰電力量で、Ｆ＞Ｅ_n （ｔ’）の分を積算するものであり、下記（３３）式で表され、また、γは第３者に売るときの価格分を一次エネルギーに換算した換算値であり、ｎ＝１〜Ｔ／ｄの総和を求めている。
【数５８】

但し、ｅ（ｔ’）＜Ｆ_m であれば、Ｅ_n （ｔ’）＝ｅ（ｔ’）
ｅ（ｔ’）≧Ｆ_m であれば、Ｅ_n （ｔ’）＝Ｆ
ここで、Ｅ_n （ｔ’）は、負荷電力が設定発電量Ｆ_m を越える場合は設定電力量となり、負荷電力が設定発電量Ｆm より小さい場合はその負荷電力量となる電力量であり、ｅ（ｔ’）は、予め特定された電力需要（負荷電力）の経時的変化を示す関数である。
【００１４】
また、請求項１１に係る発明は、前述のような目的を達成するために、
請求項１、請求項２、請求項３、請求項４、請求項５、請求項６、請求項７、請求項８、請求項９、請求項１０のいずれかに記載のコージェネレーションシステムの運転方法において、
熱電併給装置の１周期内における発停回数を設定する発停回数設定手段を備え、前記熱電併給装置の１周期内における発停回数が設定回数以下で一次エネルギーの換算値ＰＥが最小となる組み合わせの最適運転状態を求めるように構成する。
【００１５】
【作用】
請求項１および請求項２に係る発明のコージェネレーションシステムの運転方法の構成によれば、例えば、１日間など、１周期となる所定時間内において、熱電併給装置を定格発電量で運転して発電し、電力需要が定格発電量の電力よりも小さいときの電力需要を越える余剰の電力を電熱変換手段によって熱に変換し、不足分の電力を買電手段で賄うとともに、変換した熱と熱電併給装置で発生した熱によって熱需要を賄い、かつ、後で必要とする熱を蓄熱タンクに貯めて熱需要に応じるとともに、不足分の熱を補助加熱手段で補うことができる。
このときに、例えば、１日などの１周期内にとどまらず、翌日の午前分や昼分の熱需要など次の１周期内の熱需要の一部を賄うために消費することを許容し、蓄熱タンクに貯めた熱が消費までの間に放熱するなどのシステムからの放熱分と、不足分の電力を買電手段で賄うことと、変換した熱や熱電併給装置で発生した熱や蓄熱タンクに貯めた熱量で熱需要を賄うのに不足するときに不足分の熱を補助加熱手段で補うことをも考慮して、１周期を設定時間間隔で分割し、その分割時間ごとに熱電併給装置を運転する状態と停止する状態それぞれで、蓄熱タンク内の蓄熱量が０以上でかつ最大蓄熱量を越えないようにして、請求項２に係る発明の場合には２の（Ｔ／ｄ）乗分といったように仮想の運転状態の組み合わせを求め、それに基づいて、全体の一次エネルギーへの変換値が最小となる組み合わせを求め、その組み合わせに従って運転する。
【００１６】
また、請求項３および請求項４に係る発明のコージェネレーションシステムの運転方法の構成によれば、例えば、１日間など、１周期となる所定時間内において、電力需要が定格発電量を越えるときは熱電併給装置を定格発電量で運転して発電し、電力需要が定格発電量よりも小さいときは熱電併給装置を電力需要に追従して運転して発電し、不足分の電力を買電手段で賄うとともに熱電併給装置で発生した熱によって熱需要を賄い、かつ、後で必要とする熱を蓄熱タンクに貯めて熱需要に応じるとともに、不足分の熱を補助加熱手段で補うことができる。
このときに、例えば、１日などの１周期内にとどまらず、翌日の午前分や昼分の熱需要など次の１周期内の熱需要の一部を賄うために消費することを許容し、蓄熱タンクに貯めた熱が消費までの間に放熱する分と、不足分の電力を買電手段で賄うことと、変換した熱や熱電併給装置で発生した熱や蓄熱タンクに貯めた熱量で熱需要を賄うのに不足するときに不足分の熱を補助加熱手段で補うことをも考慮して、１周期を設定時間間隔で分割し、その分割時間ごとに熱電併給装置を運転する状態と停止する状態それぞれで、蓄熱タンク内の蓄熱量が０以上でかつ最大蓄熱量を越えないようにして、請求項４に係る発明の場合には２の（Ｔ／ｄ）乗分といったように仮想の運転状態の組み合わせを求め、それに基づいて、全体の一次エネルギーへの変換値が最小となる組み合わせを求め、その組み合わせに従って運転する。
【００１７】
また、請求項５および請求項６に係る発明のコージェネレーションシステムの運転方法の構成によれば、例えば、１日間など、１周期となる所定時間内において、熱電併給装置を複数段に設定した発電量で運転して発電し、電力需要が設定発電量の電力よりも小さいときの電力需要を越える余剰の電力を電熱変換手段によって熱に変換し、不足分の電力を買電手段で賄うとともに、変換した熱と熱電併給装置で発生した熱によって熱需要を賄い、かつ、後で必要とする熱を蓄熱タンクに貯めて熱需要に応じるとともに、不足分の熱を補助加熱手段で補うことができる。
このときに、例えば、１日などの１周期内にとどまらず、翌日の午前分や昼分の熱需要など次の１周期内の熱需要の一部を賄うために消費することを許容し、蓄熱タンクに貯めた熱が消費までの間に放熱する分と、不足分の電力を買電手段で賄うことと、変換した熱や熱電併給装置で発生した熱や蓄熱タンクに貯めた熱量で熱需要を賄うのに不足するときに不足分の熱を補助加熱手段で補うことをも考慮して、１周期を設定時間間隔で分割し、その分割時間ごとに熱電併給装置を複数段に設定した発電量で運転する状態と停止する状態それぞれで、蓄熱タンク内の蓄熱量が０以上でかつ最大蓄熱量を越えないようにして、請求項６に係る発明の場合には（１＋ｍ）の（Ｔ／ｄ）乗分といったように仮想の運転状態の組み合わせを求め、それに基づいて、全体の一次エネルギーへの変換値が最小となる組み合わせを求め、その組み合わせに従って運転する。
【００１８】
また、請求項７および請求項８に係る発明のコージェネレーションシステムの運転方法の構成によれば、例えば、１日間など、１周期となる所定時間内において、熱電併給装置を定格発電量で運転して発電し、電力需要が定格発電量の電力よりも小さいときの電力需要を越える余剰の電力を売電手段によって第３者に売り、不足分の電力を買電手段で賄うとともに、熱電併給装置で発生した熱によって熱需要を賄い、かつ、後で必要とする熱を蓄熱タンクに貯めて熱需要に応じるとともに、不足分の熱を補助加熱手段で補うことができる。
このときに、例えば、１日などの１周期内にとどまらず、翌日の午前分や昼分の熱需要など次の１周期内の熱需要の一部を賄うために消費することを許容し、蓄熱タンクに貯めた熱が消費までの間に放熱するなどのシステムからの放熱分と、不足分の電力を買電手段で賄うことと、余剰の電力を売電手段によって第３者に売ること、ならびに、熱電併給装置で発生した熱や蓄熱タンクに貯めた熱量で熱需要を賄うのに不足するときに不足分の熱を補助加熱手段で補うことをも考慮して、１周期を設定時間間隔で分割し、その分割時間ごとに熱電併給装置を運転する状態と停止する状態それぞれで、蓄熱タンク内の蓄熱量が０以上でかつ最大蓄熱量を越えないようにして、請求項８に係る発明の場合には２の（Ｔ／ｄ）乗分といったように仮想の運転状態の組み合わせを求め、それに基づいて、全体の一次エネルギーへの変換値が最小となる組み合わせを求め、その組み合わせに従って運転する。
【００１９】
また、請求項９および請求項１０に係る発明のコージェネレーションシステムの運転方法の構成によれば、例えば、１日間など、１周期となる所定時間内において、熱電併給装置を複数段に設定した発電量で運転して発電し、電力需要が設定発電量の電力よりも小さいときの電力需要を越える余剰の電力を売電手段によって第３者に売り、不足分の電力を買電手段で賄うとともに、変換した熱と熱電併給装置で発生した熱によって熱需要を賄い、かつ、後で必要とする熱を蓄熱タンクに貯めて熱需要に応じるとともに、不足分の熱を補助加熱手段で補うことができる。
このときに、例えば、１日などの１周期内にとどまらず、翌日の午前分や昼分の熱需要など次の１周期内の熱需要の一部を賄うために消費することを許容し、蓄熱タンクに貯めた熱が消費までの間に放熱する分と、不足分の電力を買電手段で賄うことと、余剰の電力を売電手段によって第３者に売ること、ならびに、熱電併給装置で発生した熱や蓄熱タンクに貯めた熱量で熱需要を賄うのに不足するときに不足分の熱を補助加熱手段で補うことをも考慮して、１周期を設定時間間隔で分割し、その分割時間ごとに熱電併給装置を複数段に設定した発電量で運転する状態と停止する状態それぞれで、蓄熱タンク内の蓄熱量が０以上でかつ最大蓄熱量を越えないようにして、請求項１０に係る発明の場合には（１＋ｍ）の（Ｔ／ｄ）乗分といったように仮想の運転状態の組み合わせを求め、それに基づいて、全体の一次エネルギーへの変換値が最小となる組み合わせを求め、その組み合わせに従って運転する。
【００２０】
また、請求項１１に係る発明のコージェネレーションシステムの運転方法の構成によれば、使用する熱電併給装置個々の特性や希望する耐用年数などに応じて、その発停回数を設定し、必要以上の発停の繰り返しを回避する。
【００２１】
【発明の実施の形態】
次に、本発明の実施例につき、図面に基づいて詳細に説明する。
図１は、コージェネレーションシステムの第１実施例を示すシステム構成図であり、１は熱電併給装置を、２は蓄熱タンクをそれぞれ示している。
【００２２】
蓄熱タンク２には、その底側から上部にわたって第１のポンプ３を備えた循環配管４が接続されている。循環配管４に熱交換器５が設けられ、熱電併給装置１と熱交換器５とにわたって、第２のポンプ６を備えた熱回収用循環配管７が接続されている。
【００２３】
この構成により、蓄熱タンク２の下部から取り出した水を熱電併給装置１からの熱によって加熱し、その加熱された蓄熱水を蓄熱タンク２に戻して蓄熱するように構成されている。
循環配管４の熱交換器５よりも下流側の箇所に電熱変換手段としての電気ヒータ８が設けられ、熱電併給装置１で発生した電力が余剰の場合に、余剰電力を熱に変換して蓄熱タンク２の下部から取り出した水を加熱し、その加熱された蓄熱水を蓄熱タンク２に蓄えることができるように構成されている。図中９は、給湯用の給湯管を示している。
【００２４】
循環配管４には、熱交換器５と直列になるように出力用循環配管１０が接続されるとともに、その出力用循環配管１０に暖房用熱交換器１１が設けられ、暖房用熱交換器１１に、第３のポンプ１２を備えた暖房用循環配管１３を介して、室内暖房機、床暖房機、浴室乾燥機などのセントラルヒーティング用の暖房装置１４が接続されている。
【００２５】
熱電併給装置１には、発電電力を取り出す電力線１５が接続され、その電力線１５に、照明装置や電気機器などの電気負荷１６が接続されている。また、電力線１５に逆潮流防止用の保護装置１７を介して商用電源線１８が接続され、発電電力で不足するときに商用電源からの電力を投入できるように買電手段１９が構成されている。
【００２６】
また、電力線１５に、スイッチ回路２０を介して電気ヒータ８が接続され、余剰電力の発生時に電気ヒータ８に通電するようになっている。この電気ヒータ８としては、二点鎖線で示すように、熱回収用循環配管７に設けるようにしても良い。図中２１は補助加熱手段としてのガスボイラを示している。
【００２７】
熱電併給装置１、スイッチ回路２０およびガスボイラ２１にはマイクロコンピュータ２２が接続されている。
マイクロコンピュータ２２には、図２のブロック図に示すように、需要変化特定手段２３と運転状態入力手段２４と演算手段２５と比較手段２６と運転制御手段２７とが備えられている。
【００２８】
需要変化特定手段２３では、図３および図４のグラフに示すように、１周期Ｔとしての１日間における、照明装置や電気機器駆動のための電力需要ｅ（ｔ’）、および、給湯や暖房などの熱需要ｈ（ｔ’）の経時的変化が、学習機能などによって予め記憶され、電力需要ｅ（ｔ’）および熱需要ｈ（ｔ’）の経時的変化を予め特定できるように構成されている。また、表−１に、上記給湯や暖房などの熱需要ｈ（ｔ’）の経時的変化の数値例を示す。なお、図３および図４は、多数の需要家の平均値をとって概略的な変化として示したものである。
【表１】

【００２９】
すなわち、前日の需要変化とか、１週間前の同じ曜日の需要変化などが順次記憶され、それらの需要変化に基づいて当日１日間および翌日１日間における熱需要ｈ（ｔ’）、および、電力需要ｅ（ｔ’）の経時的変化を、予め特定できるようになっているのである。
【００３０】
運転状態入力手段２４では、１周期Ｔとしての１日間を、例えば、３０分間ごとなど、設定時間間隔ｄで分割し、各分割時間ｄそれぞれにおいて、熱電併給装置１を定格発電量で運転する状態と停止する状態それぞれを入力していくようになっている。
【００３１】
演算手段２５では、運転状態入力手段２４から運転状態と停止状態とを後述する条件式や関係式に入力し、需要変化特定手段２３からの当日１日間における熱需要ｈ（ｔ’）、および、電力需要ｅ（ｔ’）の経時的変化とに基づき、設定時間間隔ｄが３０分であれば、２の４８乗通りの組み合わせそれぞれにおける一次エネルギーの換算値を演算するようになっている。
【００３２】
比較手段２６では、演算手段２５から入力される一次エネルギーの換算値を記憶し、その換算値と次に入力される換算値とを比較し、小さいほうの換算値とそのときの熱電併給装置１の運転状態と停止状態との組み合わせを新たに記憶していき、すべての組み合わせについて比較した後に、一次エネルギーの換算値が最小であった組み合わせを最適運転状態として出力するようになっている。
【００３３】
運転制御手段２７では、比較手段２６からの最適運転状態の組み合わせに応答して、熱電併給装置１、スイッチ回路２０およびガスボイラ２１に駆動信号を出力し、一次エネルギーの換算値が最小になる状態でコージェネレーションシステムを運転するようになっている。
【００３４】
次に、上記条件式について説明する。
第１実施例では、熱電併給装置１を発電効率が最も高い定格発電量(100％負荷) で運転し、電力需要ｅ（ｔ’）が定格発電量よりも小さい余剰電力分を電気ヒータ８によって熱に変換するものとする。ここでの定格発電量としては、１ｋｗを例示する。この定格発電量は、例えば、０．８ｋｗなど、使用する熱電併給装置１によって決まるものである。
【００３５】
先ず、設定時間間隔ｄを３０分（０．５時間）として、１周期Ｔにおける最初の１区間目の３０分間（午前０時から午前０時３０分）につき、熱電併給装置１を運転する状態と停止する状態それぞれにつき、図５の動作説明に供する参考図を用いて考察する。この図５は、前述した図３および図４とは関係が無く、説明上の参考にするために例示するものである。
【００３６】
▲１▼運転状態
図５の（ａ）の電力需要と発電量との相関を示すグラフ、および、図５の（ｂ）の熱需要と発生熱量との相関を示すグラフに示すように、余剰電力分ＹＥを電気ヒータ８で熱に変換した熱量をＨ₁ とすると、取得する熱量ＨＴ₁ は、
ＨＴ₁ ＝Ｈ₁ ＋発生熱量ＣＨ＋ガスボイラ２１で補う熱量ＢＨ
となり、変換熱量Ｈ₁ は、下記のように表される。
【数５９】

但し、ｅ（ｔ’）＜Ｆであれば、Ｅ₁ （ｔ’）＝ｅ（ｔ’）
ｅ（ｔ’）≧Ｆであれば、Ｅ₁ （ｔ’）＝Ｆ
ここで、Ｅ₁ （ｔ’）は、負荷電力が定格発電量の電力Ｆ（１ｋｗ）を越える場合は定格電力量となり、負荷電力が定格電力より小さい場合はその負荷電力量となる電力量であり、ｅ（ｔ’）は、予め特定された電力需要（負荷電力）の経時的変化を示す関数である。
【００３７】
また、発生熱量ＣＨ＝０．５・Ｆ・ｋ ……（３５）
である。ここでｋは熱電比である。
また、ガスボイラ２１で補う熱量ＢＨは、
【数６０】

となる。ＢＯ（ｔ’）は、熱量不足を生じた際に、その不足分を補うようにガスボイラ２１を起動する場合の関数を示している。図５の（ｂ）では零とする。
【００３８】
一方、消費される熱量は、熱需要量に放熱量を加えたものになり、
【数６１】

となる。ここで、ｈ（ｔ’）は、予め特定された熱需要の経時的変化を示す関数であり、ｅｘ（ｔ’）はシステムからの放熱量である。
【００３９】
これらのことから、１区間目の３０分間経過後の蓄熱量Ｓ（０．５）が、
【数６２】

となる。ここで、Ｓ（０）は、１区間目の運転開始時における初期蓄熱量である。また、蓄熱量Ｓ（０．５）としては、０以上であるとともに、蓄熱タンク２の最大蓄熱量Ｓ_max を越えることは無く、次の条件式を満たす必要がある。
【数６３】

すなわち、ここで、熱量が不足する場合であれば、ガスボイラ２１を起動して不足分の熱量を補うことになる。
【００４０】
ここでの一次エネルギーの換算値ＰＥは、
ＰＥ＝ＧＩ₁ ・α＋ＢＩ₁ ・α’＋ＢＥ₁ ・β……（４０）
となる。ＧＩ₁ は、熱電併給装置１の運転に要する燃料供給量であり、下記（４１）式で表され、また、αは燃料の一次エネルギーへの換算値である。また、ＢＩ₁ は、ガスボイラ２１の運転に要する燃料供給量であり、α’は燃料の一次エネルギーへの換算値である。熱電併給装置１およびガスボイラ２１の燃料が同じであれば、α＝α’となる。
【数６４】

ここで、ＧＩ（ｔ’）は、使用する熱電併給装置１によって特定される燃料供給量である。
【００４１】
ＢＥ₁ は、１区間の時間（０．５時間）内での不足分の電力の投入量であり、次式（４２）で表され、また、βは電力の一次エネルギーへの換算値である。但し、ここでは、電力不足では無いために、ＢＥ₁ は零である。
【数６５】

ここで、ＧＰは、１区間の時間（０．５時間）内での熱電併給装置１の発電量であり、次式（４３）で表される。
【数６６】

ここで、Ｅ（ｔ’）は、負荷電力が定格発電量の電力を越える場合は定格電力量となり、負荷電力が定格電力より小さい場合はその負荷電力量となる電力量である。すなわち、負荷電力が定格電力より小さい場合は、電力不足を生じないため零になる。
【００４２】
▲２▼運転停止状態
図５の（ｃ）の電力需要と発電量との相関を示すグラフ、および、図５の（ｄ）の熱需要と発生熱量との相関を示すグラフに示すように、熱電併給装置１が運転されないために、電気ヒータ８で変換する熱量、および、発生熱量のいずれも零である。したがって、１区間目の３０分間経過後の蓄熱量Ｓ（０．５）は、初期蓄熱量Ｓ（０）から熱需要量と放熱量とを引いた分となる。熱量が不足したときにおいてのみ、図５の（ｄ）に一点鎖線で示すように、取得熱量ＨＴ₁ が、
ＨＴ₁ ＝ガスボイラ２１で補う熱量ＢＨ
となる。ガスボイラ２１で補う熱量ＢＨは、前述（３６）式の通りである。条件式としては、前述運転状態のときと同様に（３９）式となる。
【００４３】
この場合の一次エネルギーの換算値ＰＥは、ＧＩ₁ ・αが零となり、
ＰＥ＝ＢＩ₁ ・α’＋ＢＥ₁ ・β……（４４）
となる。
ＢＩ₁ は、ガスボイラ２１の運転に要する燃料供給量であり、α’は燃料の一次エネルギーへの換算値である。
ＢＥ₁ は、１区間の時間（０．５時間）内での不足分の電力の投入量であり、熱電併給装置１の発電量が零であるために次式（４５）で表され、また、βは電力の一次エネルギーへの換算値である。
【数６７】

【００４４】
上述のようにして、運転状態と運転停止状態とを３０分ごとの各区間で順次求めることになり、その条件式は下記（４６）式で表される。
【数６８】

ここで、ｎは１〜４８（２４÷０．５）の正の整数である。
【００４５】
一次エネルギーの換算値ＰＥは次の通りである。
ＰＥ＝ΣＰＥ_n ＝ΣＧＩ_n ・α＋ΣＢＩ_n ・α’＋ΣＢＥ_n ・β……（４７）
ここで、ΣＰＥ_n は、ｎ＝１〜４８の一次エネルギーの総和である。ＧＩ_n は熱電併給装置の運転に要する燃料供給量であり、次式（４８）で表され、また、αは燃料の一次エネルギーへの換算値であり、ΣＧＩ_n ・αはｎ＝１〜４８の総和を求めている。また、ＢＩ_n はガスボイラ２１の運転に要する燃料供給量であり、α’は燃料の一次エネルギーへの換算値であり、ΣＢＩ_n ・α’はｎ＝１〜４８の総和を求めている。
【数６９】

ここで、ＧＩ（ｔ’）は、使用する熱電併給装置によって特定される燃料供給量であり、運転停止状態では零となる。
【００４６】
ΣＢＥ_n は、１周期Ｔとなる所定時間Ｔ内での不足分の電力の投入量であり、次式（４９）で表され、また、βは電力の一次エネルギーへの換算値であり、ΣＢＥ_n ・βはｎ＝１〜４８の総和を求めている。
【数７０】

ここで、ＧＰは、熱電併給装置の発電量であり、次式（５０）で表される。
【数７１】

ここで、Ｅ（ｔ’）は、負荷電力が定格発電量の電力を越える場合は定格電力量となり、負荷電力が定格電力より小さい場合はその負荷電力量となる電力量である。
【００４７】
１周期としての１日間経過後において、その周期で取得した熱を翌日に消費することを許容するものであり、蓄熱タンク２内の蓄熱量の変動値Ｓ（ｔ＋ｎ・ｄ）は、最大蓄熱量Ｓ_max を越えない範囲のどのような値であっても良い。
【００４８】
上述の結果、下記のような、運転停止状態と運転状態との様々な組み合わせが入力されて一次エネルギーの換算値ＰＥが求められる。
▲１▼運転停止状態と運転状態とを３０分ごとに交互に繰り返して運転する。［図６の（ａ）］
▲２▼午前０時〜午前９時、午前１２時〜午後５時（１２〜１７時）、および、午後１０時〜午後１２時（２２〜２４時）それぞれを運転停止状態にし、午前９時〜午前１２時、および、午後５時〜午後１０時（１７〜２２時）それぞれを運転状態にして運転する。［図６の（ｂ）］
▲３▼午前０時〜午前６時、午後３時〜午後６時（１５〜１８時）、および、午後８時〜午後１２時（２０〜２４時）それぞれを運転停止状態にし、午前６時〜午後３時（６〜１５時）、および、午後６時〜午後８時（１８〜２０時）それぞれを運転状態にして運転する。［図６の（ｃ）］
▲３▼午前２時〜午後６時（２〜１８時）を運転停止状態にし、午前０時〜午前２時、および、午後６時〜午後１２時（１８〜２４時）それぞれを運転状態にして運転する。［図６の（ｄ）］
【００４９】
最終的に２⁴⁸通りの一次エネルギーの換算値ＰＥが比較手段２６に入力され、順次比較して一次エネルギーの換算値ＰＥの小さい方が残され、一次エネルギーの換算値ＰＥが最小となる運転状態と運転停止状態の組み合わせの最適運転状態が求められ、例えば、図７の（ａ）の電力需要と発電量との相関を示すグラフ、および、図７の（ｂ）の熱需要と発生熱量との相関を示すグラフに示すように、運転制御手段２７により、最適運転状態での運転が行われ、省エネルギー性を向上する最適な状態でコージェネレーションシステムを運転できることになる。図７において、ａは運転開始時、ｂは運転終了時を示している。
【００５０】
上記第１実施例では、１周期を１日（２４時間）として３０分間（０．５時間）の時間間隔で分割しているが、本発明としては、例えば、１日を１０分間や２０分間で分割するとか、また、生産ラインなどで、３日間とか１週間を１周期にするなど、その周期や分割時間間隔としては、適宜設定できる。
【００５１】
そこで、１周期をＴ、分割時間間隔をｄとして整理すると、以下のようになる。
蓄熱タンク２内の蓄熱量の変動値Ｓ（ｔ＋ｎ・ｄ）が常に下記条件式（１）を満たすとともに、下記一次エネルギーの換算値ＰＥ［式（４）］が最小となる組み合わせの最適運転状態を求め、求められた最適運転状態によって、熱電併給装置を定格発電量で運転するとともに電力需要が定格発電量の電力よりも小さいときの余剰電力を電気ヒータなどの電熱変換手段で熱に変換することになる。
【数７２】

ここで、Ｓ［ｔ＋（ｎ−１）ｄ］は各分割時間の運転開始時の蓄熱タンク内の蓄熱量を示している。また、ｎは、１〜Ｔ／ｄの正の整数であり、ｈ（ｔ’）は、予め特定された熱需要の経時的変化を示す関数であり、ｅｘ（ｔ’）はシステムからの放熱量である。Ｓ_max は、蓄熱タンクの最大蓄熱量を示している。
【００５２】
ＨＴ_n は分割時間間隔ｄ内での取得熱量を示し、下記（２）式で表される。
【数７３】

ここで、Ｆは定格発電量の電力を、ｋは熱電比をそれぞれ示している。また、Ｈ_n は余剰電力を電熱変換手段で熱に変換した変換熱量で、Ｆ＞Ｅ_n （ｔ’）の分を積算するものであり、下記（３）式で表される。
【数７４】

但し、ｅ（ｔ’）＜Ｆであれば、Ｅ_n （ｔ’）＝ｅ（ｔ’）
ｅ（ｔ’）≧Ｆであれば、Ｅ_n （ｔ’）＝Ｆ
ここで、Ｅ_n （ｔ’）は、負荷電力が定格発電量の電力を越える場合は定格電力量となり、負荷電力が定格電力より小さい場合はその負荷電力量となる電力量であり、ｅ（ｔ’）は、予め特定された電力需要（負荷電力）の経時的変化を示す関数である。
上記（２）式において、ＢＯ（ｔ’）は、熱量不足を生じた際に、その不足分を補うように補助加熱手段を起動する場合の関数を示している。
【００５３】
ＰＥ＝ΣＰＥ_n ＝ΣＧＩ_n ・α＋ΣＢＩ_n ・α’＋ΣＢＥ_n ・β……（４）
ここで、ΣＰＥ_n は、ｎ＝１〜Ｔ／ｄの一次エネルギーの総和である。ＧＩ_n は熱電併給装置の運転に要する燃料供給量であり、次式（５）で表され、また、αは燃料の一次エネルギーへの換算値であり、ΣＧＩ_n ・αはｎ＝１〜Ｔ／ｄの総和を求めている。また、ＢＩ_n は補助加熱手段の運転に要する燃料供給量であり、α’は燃料の一次エネルギーへの換算値であり、ΣＢＩ_n ・α’はｎ＝１〜Ｔ／ｄの総和を求めている。
【数７５】

ここで、ＧＩ（ｔ’）は、使用する熱電併給装置によって特定される燃料供給量であり、運転停止状態では零となる。
【００５４】
ΣＢＥ_n は、１周期Ｔとなる所定時間Ｔ内での不足分の電力の投入量であり、次式（６）で表され、また、βは電力の一次エネルギーへの換算値であり、ｎ＝１〜Ｔ／ｄの総和を求めている。
【数７６】

ここで、ＧＰは、熱電併給装置の発電量であり、次式（７）で表される。
【数７７】

ここで、Ｅ（ｔ’）は、負荷電力が定格発電量の電力を越える場合は定格電力量となり、負荷電力が定格電力より小さい場合はその負荷電力量となる電力量である。
【００５５】
次に、第２実施例について説明する。
この第２実施例では、電力需要ｅ（ｔ’）が定格発電量１ｋｗよりも小さいところでは、電力需要ｅ（ｔ’）に合わせて発電し、定格発電量１ｋｗよりも大きいところでは、定格発電量１ｋｗで発電するように熱電併給装置１を運転するものである。
【００５６】
また、この第２実施例では、前述第１実施例のような電気ヒータを用いないものであり、構成的には、図１および図２の電気ヒータ８およびスイッチ回路２０を無くした構成となる。
【００５７】
▲１▼運転状態
電力需要ｅ（ｔ’）が定格発電量１ｋｗよりも小さいところでは、図８の（ａ）の電力需要と発電量との相関を示すグラフに示すように、電力需要ｅ（ｔ’）に合わせて発電する。図８の（ｂ）の熱需要と発生熱量との相関を示すグラフに示すように、取得する熱量ＨＴ₁ は、
ＨＴ₁ ＝発生熱量ＣＨ＋ガスボイラ２１で補う熱量ＢＨ
となり、発生熱量ＣＨは、下記のように表される。
【数７８】

ここで、Ｅ₁ （ｔ’）は、負荷電力が定格発電量の電力を越える場合は定格電力量となり、負荷電力が定格電力より小さい場合はその負荷電力量となる電力量である。Ｂ［Ｅ₁ （ｔ’）］は、電力量Ｅ_n （ｔ’）における熱電併給装置の発生熱量を示している。図８の（ｂ）の場合は、Ｅ₁ （ｔ’）＝ｅ（ｔ’）である。
【００５８】
また、ガスボイラ２１で補う熱量ＢＨは、
【数７９】

となる。ＢＯ（ｔ’）は、熱量不足を生じた際に、その不足分を補うようにガスボイラ２１を起動する場合の関数を示している。図８の（ｂ）では零とする。
【００５９】
一方、消費される熱量は、熱需要量に放熱量を加えたものになり、
【数８０】

となる。ここで、ｈ（ｔ’）は、予め特定された熱需要の経時的変化を示す関数であり、ｅｘ（ｔ’）はシステムからの放熱量である。
【００６０】
これらのことから、１区間目の３０分間経過後の蓄熱量Ｓ（０．５）が、
【数８１】

となる。ここで、Ｓ（０）は、１区間目の運転開始時における初期蓄熱量である。また、蓄熱量Ｓ（０．５）としては、０以上であるとともに、蓄熱タンク２の最大蓄熱量Ｓ_max を越えることは無く、次の条件式を満たす必要がある。
【数８２】

すなわち、ここで、熱量が不足する場合であれば、ガスボイラ２１を起動して不足分の熱量を補うことになる。
【００６１】
ここでの一次エネルギーの換算値ＰＥは、
ＰＥ＝ＧＩ₁ ・α＋ＢＩ₁ ・α’＋ＢＥ₁ ・β……（５６）
となる。ＧＩ₁ は、熱電併給装置１の運転に要する燃料供給量であり、下記（５７）式で表され、また、αは燃料の一次エネルギーへの換算値である。また、ＢＩ₁ は、ガスボイラ２１の運転に要する燃料供給量であり、α’は燃料の一次エネルギーへの換算値である。熱電併給装置１およびガスボイラ２１の燃料が同じであれば、α＝α’となる。
【数８３】

ここで、ＧＩ（ｔ’）は、使用する熱電併給装置１によって特定される燃料供給量である。
【００６２】
ＢＥ₁ は、１区間の時間（０．５時間）内での不足分の電力の投入量であり、次式（５８）で表され、また、βは電力の一次エネルギーへの換算値である。但し、ここでは零である。
【数８４】

ここで、ＧＰは、１区間の時間（０．５時間）内での熱電併給装置１の発電量であり、次式（５９）で表される。
【数８５】

ここで、Ｅ（ｔ’）は、負荷電力が定格発電量の電力を越える場合は定格電力量となり、負荷電力が定格電力より小さい場合はその負荷電力量となる電力量である。すなわち、負荷電力が定格電力より小さい場合は、電力不足を生じないため零になる。
【００６３】
定格発電量１ｋｗよりも大きいところでは、図８の（ｃ）の電力需要と発電量との相関を示すグラフに示すように、定格発電量Ｆで発電する。図８の（ｄ）の熱需要と発生熱量との相関を示すグラフに示すように、取得する熱量ＨＴ_n は、
ＨＴ_n ＝発生熱量ＣＨ＋ガスボイラ２１で補う熱量ＢＨ
となり、発生熱量ＣＨは、下記のように表される。
ＣＨ＝０．５・Ｆ・ｋ ……（６０）
ここで、ｋは熱電比である。
【００６４】
また、ガスボイラ２１で補う熱量ＢＨは、
【数８６】

となる。ＢＯ（ｔ’）は、熱量不足を生じた際に、その不足分を補うようにガスボイラ２１を起動する場合の関数を示している。図８の（ｄ）では零とする。
【００６５】
一方、消費される熱量は、熱需要量に放熱量を加えたものになり、
【数８７】

となる。ここで、ｈ（ｔ’）は、予め特定された熱需要の経時的変化を示す関数であり、ｅｘ（ｔ’）はシステムからの放熱量である。
【００６６】
これらのことから、ｎ区間目の３０分間経過後の蓄熱量Ｓ（０．５ｎ）が、
【数８８】

となる。ここで、Ｓ［０．５（ｎ−１）］は、（ｎ−１）区間目の運転開始時における初期蓄熱量である。また、蓄熱量Ｓ（０．５ｎ）としては、０以上であるとともに、蓄熱タンク２の最大蓄熱量Ｓ_max を越えることは無く、次の条件式を満たす必要がある。
【数８９】

すなわち、ここで、熱量が不足する場合であれば、ガスボイラ２１を起動して不足分の熱量を補うことになる。
【００６７】
ここでの一次エネルギーの換算値ＰＥは、
ＰＥ＝ＧＩ_n ・α＋ＢＩ_n ・α’＋ＢＥ_n ・β……（６５）
となる。ＧＩ_n は、熱電併給装置１の運転に要する燃料供給量であり、下記（６６）式で表され、また、αは燃料の一次エネルギーへの換算値である。また、ＢＩ_n は、ガスボイラ２１の運転に要する燃料供給量であり、α’は燃料の一次エネルギーへの換算値である。熱電併給装置１およびガスボイラ２１の燃料が同じであれば、α＝α’となる。
【数９０】

ここで、ＧＩ（ｔ’）は、使用する熱電併給装置１によって特定される燃料供給量である。
【００６８】
ＢＥ_n は、１区間の時間（０．５時間）内での不足分の電力の投入量であり、次式（６７）で表され、また、βは電力の一次エネルギーへの換算値である。
【数９１】

ここで、ＧＰは、１区間の時間（０．５時間）内での熱電併給装置１の発電量であり、次式（６８）で表される。
【数９２】

ここで、Ｅ（ｔ’）は、負荷電力が定格発電量の電力を越える場合は定格電力量となり、負荷電力が定格電力より小さい場合はその負荷電力量となる電力量である。すなわち、負荷電力が定格電力より小さい場合は、電力不足を生じないため零になる。
【００６９】
▲２▼運転停止状態
前述第１実施例において電気ヒータ８で変換する熱量が零であるため、電気ヒータ８を設けない場合と同じであり、この第２実施例の作用も、図５の（ｃ）および（ｄ）によって説明した第１実施例における運転停止状態と同じであり、説明は省略する。
【００７０】
この第２実施例によれば、最終的に２⁴⁸通りの一次エネルギーの換算値ＰＥが比較手段２６に入力され、順次比較して一次エネルギーの換算値ＰＥの小さい方が残され、一次エネルギーの換算値ＰＥが最小となる運転状態と運転停止状態の組み合わせの最適運転状態が求められ、例えば、図９の（ａ）の電力需要と発電量との相関を示すグラフ、および、図９の（ｂ）の熱需要と発生熱量との相関を示すグラフに示すように、運転制御手段２７により、最適運転状態での運転が行われ、省エネルギー性を向上する最適な状態でコージェネレーションシステムを運転できることになる。図９において、ａは運転開始時、ｂは運転終了時を示している。
【００７１】
以上のことから、１周期をＴ、分割時間間隔をｄとして整理すると、以下のようになる。
蓄熱タンク２内の蓄熱量の変動値Ｓ（ｔ＋ｎ・ｄ）が常に下記条件式（８）を満たすとともに、下記一次エネルギーの換算値ＰＥ［式（１０）］が最小となる組み合わせの最適運転状態を求め、求められた最適運転状態によって、熱電併給装置を定格発電量で運転するとともに電力需要が定格発電量の電力よりも小さいときには電力需要の変化に追従させて運転することとなる。
【数９３】

ここで、Ｓ［ｔ＋（ｎ−１）ｄ］は各分割時間の運転開始時の蓄熱タンク内の蓄熱量を示している。また、ｎは、１〜Ｔ／ｄの正の整数であり、ｈ（ｔ’）は、予め特定された熱需要の経時的変化を示す関数であり、ｅｘ（ｔ’）はシステムからの放熱量である。Ｓ_max は、蓄熱タンクの最大蓄熱量を示している。
【００７２】
ＨＴ_n は分割時間間隔ｄ内での取得熱量を示し、下記（９）式で表される。
【数９４】

ここで、Ｅ_n （ｔ’）は、負荷電力が定格発電量の電力を越える場合は定格電力量となり、負荷電力が定格電力より小さい場合はその負荷電力量となる電力量である。Ｂ［Ｅ_n （ｔ’）］は、電力量Ｅ_n （ｔ’）における熱電併給装置の発生熱量を示している。
また、ＢＯ（ｔ’）は、熱量不足を生じた際に、その不足分を補うように補助加熱手段を起動する場合の関数を示している。
【００７３】
ＰＥ＝ΣＰＥ_n ＝ΣＧＩ_n ・α＋ΣＢＩ_n ・α’＋ΣＢＥ_n ・β……（１０）
ここで、ΣＰＥ_n は、ｎ＝１〜Ｔ／ｄの一次エネルギーの総和である。ＧＩ_n は熱電併給装置の運転に要する燃料供給量であり、次式（５ａ）で表され、また、αは燃料の一次エネルギーへの換算値であり、ΣＧＩ_n ・αはｎ＝１〜Ｔ／ｄの総和を求めている。また、ＢＩ_n は補助加熱手段の運転に要する燃料供給量であり、α’は燃料の一次エネルギーへの換算値であり、ΣＢＩ_n ・α’はｎ＝１〜Ｔ／ｄの総和を求めている。
【数９５】

ここで、ＧＩ（ｔ’）は、使用する熱電併給装置によって特定される燃料供給量であり、運転停止状態では零となる。
【００７４】
ΣＢＥ_n は、１周期Ｔとなる所定時間Ｔ内での不足分の電力の投入量であり、次式（１０）で表され、また、βは電力の一次エネルギーへの換算値であり、ｎ＝１〜Ｔ／ｄの総和を求めている。
【数９６】

ここで、ＧＰは、熱電併給装置の発電量であり、次式（１１）で表される。
【数９７】

ここで、Ｅ（ｔ’）は、負荷電力が定格発電量の電力を越える場合は定格電力量となり、負荷電力が定格電力より小さい場合はその負荷電力量となる電力量であり、ｅ（ｔ’）は、予め特定された電力需要（負荷電力）の経時的変化を示す関数である。
【００７５】
次に、第３実施例について説明する。
この第３実施例では、熱電併給装置１を５００ｗと定格発電量１ｋｗとの２段に設定した発電量で運転するものとする。すなわち、この第３実施例では、設定時間間隔ｄを３０分（０．５時間）として、１周期Ｔにおける最初の１区間目の３０分間（午前０時から午前０時３０分）につき、熱電併給装置１を定格発電量１ｋｗで運転する状態、５００ｗで運転する状態、および、運転を停止する状態それぞれにつき、図８の動作説明に供する参考図を用いて考察する。
また、この第３実施例では、第１実施例と同様に電熱変換手段としての電気ヒータ８を備え、発電電力が電力需要を越えた余剰電力分は熱に変換するようにしている。
【００７６】
▲１▼定格発電量１ｋｗでの運転状態
図１０の（ａ）の電力需要と発電量との相関を示すグラフ、および、図１０の（ｂ）の熱需要と発生熱量との相関を示すグラフに示すように、余剰電力分ＹＥを電気ヒータ８で熱に変換した熱量をＨ₁ とすると、取得する熱量ＨＴ₁ は、
ＨＴ₁ ＝Ｈ₁ ＋発生熱量ＣＨ＋ガスボイラ２１で補う熱量ＢＨ
となり、変換熱量Ｈ₁ は、下記のように表される。
【数９８】

但し、ｅ（ｔ’）＜Ｆ₁ であれば、Ｅ₁ （ｔ’）＝ｅ（ｔ’）
ｅ（ｔ’）≧Ｆ₁ であれば、Ｅ₁ （ｔ’）＝Ｆ₁
ここで、Ｅ₁ （ｔ’）は、負荷電力が定格発電量の電力Ｆ₁ （１ｋｗ）を越える場合は定格電力量となり、負荷電力が定格電力より小さい場合はその負荷電力量となる電力量であり、ｅ（ｔ’）は、予め特定された電力需要（負荷電力）の経時的変化を示す関数である。
【００７７】
また、発生熱量ＣＨ＝０．５・Ｆ₁ ・ｋ₁ ……（７０）
である。ここでｋ₁ は、定格発電量Ｆ₁ （１ｋｗ）での運転した時の熱電比である。
また、ガスボイラ２１で補う熱量ＢＨは、
【数９９】

となる。ＢＯ（ｔ’）は、熱量不足を生じた際に、その不足分を補うようにガスボイラ２１を起動する場合の関数を示している。図１０の（ｂ）では零とする。
【００７８】
一方、消費される熱量は、熱需要量に放熱量を加えたものになり、
【数１００】

となる。ここで、ｈ（ｔ’）は、予め特定された熱需要の経時的変化を示す関数であり、ｅｘ（ｔ’）はシステムからの放熱量である。
【００７９】
これらのことから、１区間目の３０分間経過後の蓄熱量Ｓ（０．５）が、
【数１０１】

となる。ここで、Ｓ（０）は、１区間目の運転開始時における初期蓄熱量である。また、蓄熱量Ｓ（０．５）としては、０以上であるとともに、蓄熱タンク２の最大蓄熱量Ｓ_max を越えることは無く、次の条件式を満たす必要がある。
【数１０２】

すなわち、ここで、熱量が不足する場合であれば、ガスボイラ２１を起動して不足分の熱量を補うことになる。
【００８０】
ここでの一次エネルギーの換算値ＰＥは、
ＰＥ＝ＧＩ₁ ・α＋ＢＩ₁ ・α’＋ＢＥ₁ ・β……（７５）
となる。ＧＩ₁ は、熱電併給装置１の運転に要する燃料供給量であり、下記（７６）式で表され、また、αは燃料の一次エネルギーへの換算値である。また、ＢＩ₁ は、ガスボイラ２１の運転に要する燃料供給量であり、α’は燃料の一次エネルギーへの換算値である。熱電併給装置１およびガスボイラ２１の燃料が同じであれば、α＝α’となる。
【数１０３】

ここで、ＧＩ（ｔ’）は、使用する熱電併給装置１によって特定される燃料供給量である。
【００８１】
ＢＥ₁ は、１区間の時間（０．５時間）内での不足分の電力の投入量であり、次式（７７）で表され、また、βは電力の一次エネルギーへの換算値である。但し、ここでは零である。
【数１０４】

ここで、ＧＰは、１区間の時間（０．５時間）内での熱電併給装置１の発電量であり、次式（７８）で表される。
【数１０５】

ここで、Ｅ₁ （ｔ’）は、負荷電力が定格発電量１ｋｗの電力を越える場合は定格電力量１ｋｗとなり、負荷電力が定格発電量１ｋｗの電力より小さい場合はその負荷電力量となる電力量である。すなわち、負荷電力が定格電力より小さい場合は、電力不足を生じないため零になる。
【００８２】
▲２▼発電量５００ｗでの運転状態
図１０の（ｃ）の電力需要と発電量との相関を示すグラフ、および、図１０の（ｄ）の熱需要と発生熱量との相関を示すグラフに示すように、発電電力Ｆ₂ が電力需要ｅ（ｔ’）よりも小さくて余剰電力分が無いために、変換熱量Ｈ₁ が零であり、取得する熱量ＨＴ₁ は、
ＨＴ₁ ＝発生熱量ＣＨ＋ガスボイラ２１で補う熱量ＢＨ
となる。
【００８３】
また、発生熱量ＣＨ＝０．５・Ｆ₂ ・ｋ₂ ……（７９）
である。ここでｋ₂ は、発電量Ｆ₂ （５００ｋｗ）での運転した時の熱電比である。
また、ガスボイラ２１で補う熱量ＢＨは、
【数１０６】

となる。ＢＯ（ｔ’）は、熱量不足を生じた際に、その不足分を補うようにガスボイラ２１を起動する場合の関数を示している。図１０の（ｄ）では零とする。
【００８４】
一方、消費される熱量は、熱需要量に放熱量を加えたものになり、
【数１０７】

となる。ここで、ｈ（ｔ’）は、予め特定された熱需要の経時的変化を示す関数であり、ｅｘ（ｔ’）はシステムからの放熱量である。
【００８５】
これらのことから、１区間目の３０分間経過後の蓄熱量Ｓ（０．５）が、
【数１０８】

となる。ここで、Ｓ（０）は、１区間目の運転開始時における初期蓄熱量である。また、蓄熱量Ｓ（０．５）としては、０以上であるとともに、蓄熱タンク２の最大蓄熱量Ｓ_max を越えることは無く、次の条件式を満たす必要がある。
【数１０９】

すなわち、ここで、熱量が不足する場合であれば、ガスボイラ２１を起動して不足分の熱量を補うことになる。
【００８６】
ここでの一次エネルギーの換算値ＰＥは、
ＰＥ＝ＧＩ₁ ・α＋ＢＩ₁ ・α’＋ＢＥ₁ ・β……（８４）
となる。ＧＩ₁ は、熱電併給装置１の運転に要する燃料供給量であり、下記（８５）式で表され、また、αは燃料の一次エネルギーへの換算値である。また、ＢＩ₁ は、ガスボイラ２１の運転に要する燃料供給量であり、α’は燃料の一次エネルギーへの換算値である。熱電併給装置１およびガスボイラ２１の燃料が同じであれば、α＝α’となる。
【数１１０】

ここで、ＧＩ（ｔ’）は、使用する熱電併給装置１によって特定される燃料供給量である。
【００８７】
ＢＥ₁ は、１区間の時間（０．５時間）内での不足分の電力の投入量であり、次式（８６）で表され、また、βは電力の一次エネルギーへの換算値である。
【数１１１】

ここで、ＧＰは、１区間の時間（０．５時間）内での熱電併給装置１の発電量であり、次式（８７）で表される。
【数１１２】

ここで、Ｅ₁ （ｔ’）は、負荷電力が設定発電量５００ｗの電力を越える場合は設定電力量５００ｗとなり、負荷電力が設定発電量５００ｗの電力より小さい場合はその負荷電力量となる電力量である。
【００８８】
▲３▼運転停止状態
この第３実施例の作用は、図５の（ｃ）および（ｄ）によって説明した第１実施例における運転停止状態と同じであり、説明は省略する。
【００８９】
この第３実施例の場合、最終的に３⁴⁸通りの一次エネルギーの換算値ＰＥが比較手段２６に入力され、順次比較して一次エネルギーの換算値ＰＥの小さい方が残され、一次エネルギーの換算値ＰＥが最小となる、発電量５００ｗおよび１ｋｗそれぞれの運転状態と運転停止状態の組み合わせの最適運転状態が求められ、例えば、図１１の（ａ）の電力需要と発電量との相関を示すグラフ、および、図１１の（ｂ）の熱需要と発生熱量との相関を示すグラフに示すように、運転制御手段２７により、最適運転状態での運転が行われ、省エネルギー性を向上する最適な状態でコージェネレーションシステムを運転できることになる。図１１において、ａ１は発電量５００ｗでの運転開始時、ａ２は発電量５００ｗでの運転終了時でかつ発電量１ｋｗでの運転開始時、ａ３は発電量１ｋｗでの運転終了時を示している。
【００９０】
１周期としての１日間経過後において、その周期で取得した熱を翌日に消費することを許容するものであり、蓄熱タンク２内の蓄熱量の変動値Ｓ（ｔ＋ｎ・ｄ）は、最大蓄熱量Ｓ_max を越えない範囲のどのような値であっても良い。
また、上記第３実施例では、５００ｗ運転および定格発電量１ｋｗ運転の２種類のステップ運転を行うようにしているが、本発明としては、例えば、７００ｗ運転および定格発電量１ｋｗ運転の２段に設定した発電量の運転を行うとか、５００ｗ運転、７００ｗ運転および定格発電量１ｋｗ運転などの３段以上に設定した発電量の運転を行うようにしても良く、要するに複数段の設定発電量で運転する場合を含むものである。
【００９１】
以上のことから、１周期をＴ、分割時間間隔をｄとして整理すると、以下のようになる。
蓄熱タンク２内の蓄熱量の変動値Ｓ（ｔ＋ｎ・ｄ）が常に下記条件式（１３）を満たすとともに、下記一次エネルギーの換算値ＰＥ［式（１６）］が最小となる組み合わせの最適運転状態を求め、求められた最適運転状態によって、熱電併給装置１を複数段の設定発電量で運転するとともに電力需要が設定発電量の電力よりも小さいときの余剰電力を電気ヒータなどの電熱変換手段で熱に変換することになる。
【数１１３】

ここで、Ｓ［ｔ＋（ｎ−１）ｄ］は各分割時間の運転開始時の蓄熱タンク内の蓄熱量を示している。また、ｎは、１〜Ｔ／ｄの正の整数であり、ｈ（ｔ’）は、予め特定された熱需要の経時的変化を示す関数であり、ｅｘ（ｔ’）はシステムからの放熱量である。Ｓ_max は、蓄熱タンクの最大蓄熱量を示している。
【００９２】
ＨＴ_n は分割時間間隔ｄ内での取得熱量を示し、下記（１４）式で表される。
【数１１４】

ここで、Ｆ_m は設定発電量を、ｋ_m は設定発電量Ｆ_m での熱電比をそれぞれ示している。ｍは、２以上で発電量の設定段数までの正の整数である。また、Ｈ_n は余剰電力を電熱変換手段で熱に変換した変換熱量で、Ｆ_m ＞Ｅ_n （ｔ’）の分を積算するものであり、下記（１５）式で表される。
【数１１５】

但し、ｅ（ｔ’）＜Ｆ_m であれば、Ｅ_n （ｔ’）＝ｅ（ｔ’）
ｅ（ｔ’）≧Ｆ_m であれば、Ｅ_n （ｔ’）＝Ｆ_m
ここで、Ｅ_n （ｔ’）は、負荷電力が設定発電量Ｆ_m を越える場合は設定電力量となり、負荷電力が設定発電量Ｆ_m より小さい場合はその負荷電力量となる電力量であり、ｅ（ｔ’）は、予め特定された電力需要（負荷電力）の経時的変化を示す関数である。
上記（１４）式において、ＢＯ（ｔ’）は、熱量不足を生じた際に、その不足分を補うように補助加熱手段を起動する場合の関数を示している。
【００９３】
ＰＥ＝ΣＰＥ_n ＝ΣＧＩ_n ・α＋ΣＢＩ_n ・α’＋ΣＢＥ_n ・β……（１６）
ここで、ΣＰＥ_n は、ｎ＝１〜Ｔ／ｄの一次エネルギーの総和である。ＧＩ_n は熱電併給装置の運転に要する燃料供給量であり、次式（１７）で表され、また、αは燃料の一次エネルギーへの換算値であり、ΣＧＩ_n ・αはｎ＝１〜Ｔ／ｄの総和を求めている。また、ＢＩ_n は補助加熱手段の運転に要する燃料供給量であり、α’は燃料の一次エネルギーへの換算値であり、ΣＢＩ_n ・α’はｎ＝１〜Ｔ／ｄの総和を求めている。
【数１１６】

ここで、ＧＩ（ｔ’）は、使用する熱電併給装置によって特定される燃料供給量であり、運転停止状態では零となる。
【００９４】
ΣＢＥ_n は、１周期Ｔとなる所定時間Ｔ内での不足分の電力の投入量であり、次式（１８）で表され、また、βは電力の一次エネルギーへの換算値であり、ｎ＝１〜Ｔ／ｄの総和を求めている。
【数１１７】

ここで、ＧＰは、熱電併給装置の発電量であり、次式（１９）で表される。
【数１１８】

ここで、Ｅ（ｔ’）は、負荷電力が設定発電量Ｆ_m を越える場合は設定電力量となり、負荷電力が設定発電量Ｆ_m より小さい場合はその負荷電力量となる電力量である。
【００９５】
図１２は、コージェネレーションシステムの第４実施例を示すシステム構成図であり、第１実施例と異なるところは次の通りである。
すなわち、電気ヒータ８を無くし、電力線１５に、スイッチ回路３１を介して電力供給線３２が接続され、余剰電力の発生時に、その余剰電力分を第３者に売るように売電手段３３が構成されている。
電力供給線３２には電力計３４が介装され、第３者に売った電力量を計測するように構成されている。他の構成は第１実施例と同じであり、同一図番を付すことによりその説明は省略する。
【００９６】
図１３の第４実施例のブロック図に示すように、熱電併給装置１、スイッチ回路３１およびガスボイラ２１にはマイクロコンピュータ３５が接続されている。
マイクロコンピュータ３５には、前述第１実施例と同様に、需要変化特定手段２３と運転状態入力手段２４と演算手段２５と比較手段２６と運転制御手段２７とが備えられている。
【００９７】
この第４実施例では、電気ヒータ８で熱に変換しない分だけ取得熱量が減少し、かつ、第３者に売った余剰電力分を一次エネルギーに換算した分だけ一次エネルギーの換算値が減少することになり、次に説明する。
【００９８】
▲１▼運転状態
取得する熱量ＨＴ₁ は、
ＨＴ₁ ＝発生熱量ＣＨ＋ガスボイラ２１で補う熱量ＢＨ
となる。
【００９９】
また、発生熱量ＣＨ＝０．５・Ｆ・ｋ ……（８８）
である。ここでｋは熱電比である。
また、ガスボイラ２１で補う熱量ＢＨは、
【数１１９】

となる。ＢＯ（ｔ’）は、熱量不足を生じた際に、その不足分を補うようにガスボイラ２１を起動する場合の関数を示している。
【０１００】
一方、消費される熱量は、熱需要量に放熱量を加えたものになり、
【数１２０】

となる。ここで、ｈ（ｔ’）は、予め特定された熱需要の経時的変化を示す関数であり、ｅｘ（ｔ’）はシステムからの放熱量である。
【０１０１】
これらのことから、１区間目の３０分間経過後の蓄熱量Ｓ（０．５）が、
【数１２１】

となる。ここで、Ｓ（０）は、１区間目の運転開始時における初期蓄熱量である。また、蓄熱量Ｓ（０．５）としては、０以上であるとともに、蓄熱タンク２の最大蓄熱量Ｓ_max を越えることは無く、次の条件式を満たす必要がある。
【数１２２】

すなわち、ここで、熱量が不足する場合であれば、ガスボイラ２１を起動して不足分の熱量を補うことになる。
【０１０２】
ここでの一次エネルギーの換算値ＰＥは、
ＰＥ＝ＧＩ₁ ・α＋ＢＩ₁ ・α’＋ＢＥ₁ ・β−ＳＥ₁ ・γ……（９３）
となる。ＧＩ₁ は、熱電併給装置１の運転に要する燃料供給量であり、下記（９４）式で表され、また、αは燃料の一次エネルギーへの換算値である。また、ＢＩ₁ は、ガスボイラ２１の運転に要する燃料供給量であり、α’は燃料の一次エネルギーへの換算値である。熱電併給装置１およびガスボイラ２１の燃料が同じであれば、α＝α’となる。
【数１２３】

ここで、ＧＩ（ｔ’）は、使用する熱電併給装置１によって特定される燃料供給量である。
【０１０３】
ＢＥ₁ は、１区間の時間（０．５時間）内での不足分の電力の投入量であり、次式（９５）で表され、また、βは電力の一次エネルギーへの換算値である。但し、ここでは、電力不足では無いために、ＢＥ₁ は零である。
【数１２４】

ここで、ＧＰは、１区間の時間（０．５時間）内での熱電併給装置１の発電量であり、次式（９６）で表される。
【数１２５】

ここで、Ｅ（ｔ’）は、負荷電力が定格発電量の電力を越える場合は定格電力量となり、負荷電力が定格電力より小さい場合はその負荷電力量となる電力量である。すなわち、負荷電力が定格電力より小さい場合は、電力不足を生じないため零になる。
【０１０４】
また、ＳＥ₁ は、売電手段で第３者に売る余剰電力量［図５の（ａ）の余剰電力分ＹＥに相当］で、Ｆ＞Ｅ₁ （ｔ’）の分を積算するものであり、下記（９７）式で表され、また、γは第３者に売るときの価格分を一次エネルギーに換算した換算値である。
【数１２６】

但し、ｅ（ｔ’）＜Ｆであれば、Ｅ₁ （ｔ’）＝ｅ（ｔ’）
ｅ（ｔ’）≧Ｆであれば、Ｅ₁ （ｔ’）＝Ｆ
ここで、Ｅ₁ （ｔ’）は、負荷電力が定格発電量の電力を越える場合は定格電力量となり、負荷電力が定格電力より小さい場合はその負荷電力量となる電力量であり、ｅ（ｔ’）は、予め特定された電力需要（負荷電力）の経時的変化を示す関数である。
【０１０５】
▲２▼運転停止状態
熱電併給装置１が運転されないために、余剰電力が発生せず、第１実施例で説明した場合と同じである。すなわち、取得熱量ＨＴ₁ が、
ＨＴ₁ ＝ガスボイラ２１で補う熱量ＢＨ
となり、ガスボイラ２１で補う熱量ＢＨは、前述（８９）式の通りである。条件式としては、前述運転状態のときと同様に（９２）式となる。
【０１０６】
この場合の一次エネルギーの換算値ＰＥは、ＧＩ₁ ・αおよびＳＥ₁ ・γが零となり、
ＰＥ＝ＢＩ₁ ・α’＋ＢＥ₁ ・β……（９８）
となる。
ＢＩ₁ は、ガスボイラ２１の運転に要する燃料供給量であり、α’は燃料の一次エネルギーへの換算値である。
ＢＥ₁ は、１区間の時間（０．５時間）内での不足分の電力の投入量であり、熱電併給装置１の発電量が零であるために次式（９９）で表され、また、βは電力の一次エネルギーへの換算値である。
【数１２７】

【０１０７】
上述のようにして、運転状態と運転停止状態とを３０分ごとの各区間で順次求めることになり、その条件式は下記（１００）式で表される。
【数１２８】

ここで、ｎは１〜４８（２４÷０．５）の正の整数である。
【０１０８】
一次エネルギーの換算値ＰＥは次の通りである。

ここで、ΣＰＥ_n は、ｎ＝１〜４８の一次エネルギーの総和である。ＧＩ_n は熱電併給装置の運転に要する燃料供給量であり、次式（１０２）で表され、また、αは燃料の一次エネルギーへの換算値であり、ΣＧＩ_n ・αはｎ＝１〜４８の総和を求めている。また、ＢＩ_n はガスボイラ２１の運転に要する燃料供給量であり、α’は燃料の一次エネルギーへの換算値であり、ΣＢＩ_n ・α’はｎ＝１〜４８の総和を求めている。
【数１２９】

ここで、ＧＩ（ｔ’）は、使用する熱電併給装置によって特定される燃料供給量であり、運転停止状態では零となる。
【０１０９】
ΣＢＥ_n は、１周期Ｔとなる所定時間Ｔ内での不足分の電力の投入量であり、次式（１０３）で表され、また、βは電力の一次エネルギーへの換算値であり、ΣＢＥ_n ・βはｎ＝１〜４８の総和を求めている。
【数１３０】

ここで、ＧＰは、熱電併給装置の発電量であり、次式（１０４）で表される。
【数１３１】

ここで、Ｅ（ｔ’）は、負荷電力が定格発電量の電力を越える場合は定格電力量となり、負荷電力が定格電力より小さい場合はその負荷電力量となる電力量である。
【０１１０】
また、ΣＳＥ_n は売電手段で第３者に売る余剰電力量で、Ｆ＞Ｅ_n （ｔ’）の分を積算するものであり、下記（１０５）式で表され、また、γは第３者に売るときの価格分を一次エネルギーに換算した換算値であり、ｎ＝１〜４８の総和を求めている。
【数１３２】

但し、ｅ（ｔ’）＜Ｆであれば、Ｅ_n （ｔ’）＝ｅ（ｔ’）
ｅ（ｔ’）≧Ｆであれば、Ｅ_n （ｔ’）＝Ｆ
ここで、Ｅ_n （ｔ’）は、負荷電力が定格発電量の電力を越える場合は定格電力量となり、負荷電力が定格電力より小さい場合はその負荷電力量となる電力量であり、ｅ（ｔ’）は、予め特定された電力需要（負荷電力）の経時的変化を示す関数である。
【０１１１】
１周期としての１日間経過後において、その周期で取得した熱を翌日に消費することを許容するものであり、蓄熱タンク２内の蓄熱量の変動値Ｓ（ｔ＋ｎ・ｄ）は、最大蓄熱量Ｓ_max を越えない範囲のどのような値であっても良い。
【０１１２】
上述の結果、第１実施例と同様に、運転停止状態と運転状態との様々な組み合わせが入力されて一次エネルギーの換算値ＰＥが求められる。
【０１１３】
最終的に２⁴⁸通りの一次エネルギーの換算値ＰＥが比較手段２６に入力され、順次比較して一次エネルギーの換算値ＰＥの小さい方が残され、一次エネルギーの換算値ＰＥが最小となる運転状態と運転停止状態の組み合わせの最適運転状態が求められ、運転制御手段２７により、最適運転状態での運転が行われ、省エネルギー性を向上する最適な状態でコージェネレーションシステムを運転できることになる。
【０１１４】
この第４実施例において、１周期をＴ、分割時間間隔をｄとして整理すると、以下のようになる。
蓄熱タンク２内の蓄熱量の変動値Ｓ（ｔ＋ｎ・ｄ）が常に下記条件式（２０）を満たすとともに、下記一次エネルギーの換算値ＰＥ［式（２２）］が最小となる組み合わせの最適運転状態を求め、求められた最適運転状態によって、熱電併給装置を定格発電量で運転するとともに電力需要が定格発電量の電力よりも小さいときの余剰電力を売電手段３３で第３者に売ることになる。
【数１３３】

ここで、Ｓ［ｔ＋（ｎ−１）ｄ］は各分割時間の運転開始時の蓄熱タンク内の蓄熱量を示している。また、ｎは、１〜Ｔ／ｄの正の整数であり、ｈ（ｔ’）は、予め特定された熱需要の経時的変化を示す関数であり、ｅｘ（ｔ’）はシステムからの放熱量である。Ｓ_max は、蓄熱タンクの最大蓄熱量を示している。
ＨＴ_n は分割時間間隔ｄ内での取得熱量を示し、下記（２１）式で表される。
【数１３４】

ここで、Ｆは定格発電量の電力を、ｋは熱電比をそれぞれ示している。
上記（２１）式において、ＢＯ（ｔ’）は、熱量不足を生じた際に、その不足分を補うように補助加熱手段を起動する場合の関数を示している。

ここで、ΣＰＥ_n は、ｎ＝１〜Ｔ／ｄの一次エネルギーの総和である。ＧＩ_n は熱電併給装置の運転に要する燃料供給量であり、次式（２３）で表され、また、αは燃料の一次エネルギーへの換算値であり、ΣＧＩ_n ・αはｎ＝１〜Ｔ／ｄの総和を求めている。また、ＢＩ_n は補助加熱手段の運転に要する燃料供給量であり、α’は燃料の一次エネルギーへの換算値であり、ΣＢＩ_n ・α’はｎ＝１〜Ｔ／ｄの総和を求めている。
【数１３５】

ここで、ＧＩ（ｔ’）は、使用する熱電併給装置によって特定される燃料供給量であり、運転停止状態では零となる。
ΣＢＥ_n は、１周期Ｔとなる所定時間Ｔ内での不足分の電力の投入量であり、次式（２４）で表され、また、βは電力の一次エネルギーへの換算値であり、ｎ＝１〜Ｔ／ｄの総和を求めている。
【数１３６】

ここで、ＧＰは、熱電併給装置の発電量であり、次式（２５）で表される。
【数１３７】

ここで、Ｅ（ｔ’）は、負荷電力が定格発電量の電力を越える場合は定格電力量となり、負荷電力が定格電力より小さい場合はその負荷電力量となる電力量である。また、ΣＳＥ_n は売電手段で第３者に売る余剰電力量で、Ｆ＞Ｅ_n （ｔ’）の分を積算するものであり、下記（２６）式で表され、また、γは第３者に売るときの価格分を一次エネルギーに換算した換算値であり、ｎ＝１〜Ｔ／ｄの総和を求めている。
【数１３８】

但し、ｅ（ｔ’）＜Ｆであれば、Ｅ_n （ｔ’）＝ｅ（ｔ’）
ｅ（ｔ’）≧Ｆであれば、Ｅ_n （ｔ’）＝Ｆ
ここで、Ｅ_n （ｔ’）は、負荷電力が定格発電量の電力を越える場合は定格電力量となり、負荷電力が定格電力より小さい場合はその負荷電力量となる電力量であり、ｅ（ｔ’）は、予め特定された電力需要（負荷電力）の経時的変化を示す関数である。
【０１１５】
次に、第５実施例について説明する。
この第５実施例では、第３実施例と同様に、熱電併給装置１を５００ｗと定格発電量１ｋｗとの２段に設定した発電量で運転するものとする。また、この第５実施例では、第４実施例と同様に売電手段３３を備え、発電電力が電力需要を越えた余剰電力分は第３者に売るようにしている。
【０１１６】
▲１▼定格発電量１ｋｗでの運転状態
取得する熱量ＨＴ₁ は、
ＨＴ₁ ＝Ｈ₁ ＋発生熱量ＣＨ＋ガスボイラ２１で補う熱量ＢＨ
となる。
【０１１７】
また、発生熱量ＣＨ＝０．５・Ｆ₁ ・ｋ₁ ……（１０６）
である。ここでｋ₁ は、定格発電量Ｆ₁ （１ｋｗ）での運転した時の熱電比である。
また、ガスボイラ２１で補う熱量ＢＨは、
【数１３９】

となる。ＢＯ（ｔ’）は、熱量不足を生じた際に、その不足分を補うようにガスボイラ２１を起動する場合の関数を示している。図１０の（ｂ）では零とする。
【０１１８】
一方、消費される熱量は、熱需要量に放熱量を加えたものになり、
【数１４０】

となる。ここで、ｈ（ｔ’）は、予め特定された熱需要の経時的変化を示す関数であり、ｅｘ（ｔ’）はシステムからの放熱量である。
【０１１９】
これらのことから、１区間目の３０分間経過後の蓄熱量Ｓ（０．５）が、
【数１４１】

となる。ここで、Ｓ（０）は、１区間目の運転開始時における初期蓄熱量である。また、蓄熱量Ｓ（０．５）としては、０以上であるとともに、蓄熱タンク２の最大蓄熱量Ｓ_max を越えることは無く、次の条件式を満たす必要がある。
【数１４２】

すなわち、ここで、熱量が不足する場合であれば、ガスボイラ２１を起動して不足分の熱量を補うことになる。
【０１２０】
ここでの一次エネルギーの換算値ＰＥは、
ＰＥ＝ＧＩ₁ ・α＋ＢＩ₁ ・α’＋ＢＥ₁ ・β−ＳＥ₁ ・γ……（１１１）
となる。ＧＩ₁ は、熱電併給装置１の運転に要する燃料供給量であり、下記（１１２）式で表され、また、αは燃料の一次エネルギーへの換算値である。また、ＢＩ₁ は、ガスボイラ２１の運転に要する燃料供給量であり、α’は燃料の一次エネルギーへの換算値である。熱電併給装置１およびガスボイラ２１の燃料が同じであれば、α＝α’となる。
【数１４３】

ここで、ＧＩ（ｔ’）は、使用する熱電併給装置１によって特定される燃料供給量である。
【０１２１】
ＢＥ₁ は、１区間の時間（０．５時間）内での不足分の電力の投入量であり、次式（１１３）で表され、また、βは電力の一次エネルギーへの換算値である。
但し、ここでは零である。
【数１４４】

ここで、ＧＰは、１区間の時間（０．５時間）内での熱電併給装置１の発電量であり、次式（１１４）で表される。
【数１４５】

ここで、Ｅ₁ （ｔ’）は、負荷電力が定格発電量１ｋｗの電力を越える場合は定格電力量１ｋｗとなり、負荷電力が定格発電量１ｋｗの電力より小さい場合はその負荷電力量となる電力量である。すなわち、負荷電力が定格電力より小さい場合は、電力不足を生じないため零になる。
【０１２２】
また、ＳＥ₁ は、売電手段で第３者に売る余剰電力量［図１０の（ａ）の余剰電力分ＹＥに相当］で、Ｆ₁ ＞Ｅ₁ （ｔ’）の分を積算するものであり、下記（１１５）式で表され、また、γは第３者に売るときの価格分を一次エネルギーに換算した換算値である。
【数１４６】

但し、ｅ（ｔ’）＜Ｆ₁ であれば、Ｅ₁ （ｔ’）＝ｅ（ｔ’）
ｅ（ｔ’）≧Ｆ₁ であれば、Ｅ₁ （ｔ’）＝Ｆ₁
ここで、Ｅ₁ （ｔ’）は、負荷電力が定格発電量の電力を越える場合は定格電力量となり、負荷電力が定格電力より小さい場合はその負荷電力量となる電力量であり、ｅ（ｔ’）は、予め特定された電力需要（負荷電力）の経時的変化を示す関数である。
【０１２３】
▲２▼発電量５００ｗでの運転状態
図１０の（ｃ）の電力需要と発電量との相関を示すグラフ、および、図１０の（ｄ）の熱需要と発生熱量との相関を示すグラフに示すように、発電電力Ｆ₂ が電力需要ｅ（ｔ’）よりも小さくて余剰電力分が無いために、変換熱量Ｈ₁ が零であり、取得する熱量ＨＴ₁ は、
ＨＴ₁ ＝発生熱量ＣＨ＋ガスボイラ２１で補う熱量ＢＨ
となる。
【０１２４】
また、発生熱量ＣＨ＝０．５・Ｆ₂ ・ｋ₂ ……（１１６）
である。ここでｋ₂ は、発電量Ｆ₂ （５００ｋｗ）での運転した時の熱電比である。
また、ガスボイラ２１で補う熱量ＢＨは、
【数１４７】

となる。ＢＯ（ｔ’）は、熱量不足を生じた際に、その不足分を補うようにガスボイラ２１を起動する場合の関数を示している。図１０の（ｄ）では零とする。
【０１２５】
一方、消費される熱量は、熱需要量に放熱量を加えたものになり、
【数１４８】

となる。ここで、ｈ（ｔ’）は、予め特定された熱需要の経時的変化を示す関数であり、ｅｘ（ｔ’）はシステムからの放熱量である。
【０１２６】
これらのことから、１区間目の３０分間経過後の蓄熱量Ｓ（０．５）が、
【数１４９】

となる。ここで、Ｓ（０）は、１区間目の運転開始時における初期蓄熱量である。また、蓄熱量Ｓ（０．５）としては、０以上であるとともに、蓄熱タンク２の最大蓄熱量Ｓ_max を越えることは無く、次の条件式を満たす必要がある。
【数１５０】

すなわち、ここで、熱量が不足する場合であれば、ガスボイラ２１を起動して不足分の熱量を補うことになる。
【０１２７】
ここでの一次エネルギーの換算値ＰＥは、
ＰＥ＝ＧＩ₁ ・α＋ＢＩ₁ ・α’＋ＢＥ₁ ・β……（１２１）
となる。ＧＩ₁ は、熱電併給装置１の運転に要する燃料供給量であり、下記（１２２）式で表され、また、αは燃料の一次エネルギーへの換算値である。また、ＢＩ₁ は、ガスボイラ２１の運転に要する燃料供給量であり、α’は燃料の一次エネルギーへの換算値である。熱電併給装置１およびガスボイラ２１の燃料が同じであれば、α＝α’となる。
【数１５１】

ここで、ＧＩ（ｔ’）は、使用する熱電併給装置１によって特定される燃料供給量である。
【０１２８】
ＢＥ₁ は、１区間の時間（０．５時間）内での不足分の電力の投入量であり、次式（１２３）で表され、また、βは電力の一次エネルギーへの換算値である。
【数１５２】

ここで、ＧＰは、１区間の時間（０．５時間）内での熱電併給装置１の発電量であり、次式（１２４）で表される。
【数１５３】

ここで、Ｅ₁ （ｔ’）は、負荷電力が設定発電量５００ｗの電力を越える場合は設定電力量５００ｗとなり、負荷電力が設定発電量５００ｗの電力より小さい場合はその負荷電力量となる電力量である。なお、この負荷電力が設定発電量５００ｗの電力より小さい場合は余剰電力が発生し、（１１１）式によって一次エネルギーの換算値が求められる。
【０１２９】
▲３▼運転停止状態
この第５実施例の作用は、図５の（ｃ）および（ｄ）によって説明した第１実施例における運転停止状態と同じであり、説明は省略する。
【０１３０】
この第５実施例の場合、最終的に３⁴⁸通りの一次エネルギーの換算値ＰＥが比較手段２６に入力され、順次比較して一次エネルギーの換算値ＰＥの小さい方が残され、一次エネルギーの換算値ＰＥが最小となる、発電量５００ｗおよび１ｋｗそれぞれの運転状態と運転停止状態の組み合わせの最適運転状態が求められ、運転制御手段２７により、最適運転状態での運転が行われ、省エネルギー性を向上する最適な状態でコージェネレーションシステムを運転できることになる。
【０１３１】
１周期としての１日間経過後において、その周期で取得した熱を翌日に消費することを許容するものであり、蓄熱タンク２内の蓄熱量の変動値Ｓ（ｔ＋ｎ・ｄ）は、最大蓄熱量Ｓ_max を越えない範囲のどのような値であっても良い。
また、上記第３実施例では、５００ｗ運転および定格発電量１ｋｗ運転の２種類のステップ運転を行うようにしているが、本発明としては、例えば、７００ｗ運転および定格発電量１ｋｗ運転の２段に設定した発電量の運転を行うとか、５００ｗ運転、７００ｗ運転および定格発電量１ｋｗ運転などの３段以上に設定した発電量の運転を行うようにしても良く、要するに複数段の設定発電量で運転する場合を含むものである。
【０１３２】
以上のことから、１周期をＴ、分割時間間隔をｄとして整理すると、以下のようになる。
蓄熱タンク２内の蓄熱量の変動値Ｓ（ｔ＋ｎ・ｄ）が常に下記条件式（２７）を満たすとともに、下記一次エネルギーの換算値ＰＥ［式（２９）］が最小となる組み合わせの最適運転状態を求め、求められた最適運転状態によって、熱電併給装置１を複数段の設定発電量で運転するとともに電力需要が設定発電量の電力よりも小さいときの余剰電力を電気ヒータなどの電熱変換手段で熱に変換することになる。
【数１５４】

ここで、Ｓ［ｔ＋（ｎ−１）ｄ］は各分割時間の運転開始時の蓄熱タンク内の蓄熱量を示している。また、ｎは、１〜Ｔ／ｄの正の整数であり、ｈ（ｔ’）は、予め特定された熱需要の経時的変化を示す関数であり、ｅｘ（ｔ’）はシステムからの放熱量である。Ｓ_max は、蓄熱タンクの最大蓄熱量を示している。
【０１３３】
ＨＴ_n は分割時間間隔ｄ内での取得熱量を示し、下記（２８）式で表される。
【数１５５】

ここで、Ｆ_m は設定発電量を、ｋ_m は設定発電量Ｆ_m での熱電比をそれぞれ示している。ｍは、２以上で発電量の設定段数までの正の整数である。
上記（２８）式において、ＢＯ（ｔ’）は、熱量不足を生じた際に、その不足分を補うように補助加熱手段を起動する場合の関数を示している。

ここで、ΣＰＥ_n は、ｎ＝１〜Ｔ／ｄの一次エネルギーの総和である。ＧＩ_n は熱電併給装置の運転に要する燃料供給量であり、次式（３０）で表され、また、αは燃料の一次エネルギーへの換算値であり、ΣＧＩ_n ・αはｎ＝１〜Ｔ／ｄの総和を求めている。また、ＢＩ_n は補助加熱手段の運転に要する燃料供給量であり、α’は燃料の一次エネルギーへの換算値であり、ΣＢＩ_n ・α’はｎ＝１〜Ｔ／ｄの総和を求めている。
【数１５６】

ここで、ＧＩ（ｔ’）は、使用する熱電併給装置によって特定される燃料供給量であり、運転停止状態では零となる。
ΣＢＥ_n は、１周期Ｔとなる所定時間Ｔ内での不足分の電力の投入量であり、次式（３１）で表され、また、βは電力の一次エネルギーへの換算値であり、ｎ＝１〜Ｔ／ｄの総和を求めている。
【数１５７】

ここで、ＧＰは、熱電併給装置の発電量であり、次式（３２）で表される。
【数１５８】

ここで、Ｅ（ｔ’）は、負荷電力が定格発電量の電力を越える場合は定格電力量となり、負荷電力が定格電力より小さい場合はその負荷電力量となる電力量である。また、ΣＳＥ_n は売電手段で第３者に売る余剰電力量で、Ｆ＞Ｅ_n （ｔ’）の分を積算するものであり、下記（３３）式で表され、また、γは第３者に売るときの価格分を一次エネルギーに換算した換算値であり、ｎ＝１〜Ｔ／ｄの総和を求めている。
【数１５９】

但し、ｅ（ｔ’）＜Ｆ_m であれば、Ｅ_n （ｔ’）＝ｅ（ｔ’）
ｅ（ｔ’）≧Ｆ_m であれば、Ｅ_n （ｔ’）＝Ｆ
ここで、Ｅ_n （ｔ’）は、負荷電力が設定発電量Ｆ_m を越える場合は設定電力量となり、負荷電力が設定発電量Ｆ_m より小さい場合はその負荷電力量となる電力量であり、ｅ（ｔ’）は、予め特定された電力需要（負荷電力）の経時的変化を示す関数である。
【０１３４】
図１４は、第６実施例のブロック図であり、第１実施例と異なるところは次の通りである。
すなわち、マイクロコンピュータ２２に熱電併給装置１の１周期内における発停回数が設定する発停回数設定手段４１が接続され、この発停回数設定手段４１で設定した発停回数を演算手段２５に入力するようになっている。
【０１３５】
演算手段２５では、運転状態入力手段２４から入力される運転状態の発停回数が、発停回数設定手段４１から入力される設定発停回数を越えたときに、一次エネルギーの換算値の演算を停止して、次の運転状態の入力に移行するようになっている。
【０１３６】
この第６実施例によれば、熱電併給装置１の１周期内における発停回数が設定回数以下で一次エネルギーの換算値ＰＥが最小となる組み合わせの最適運転状態を求めることができ、熱電併給装置１の耐久性を向上できる。
発停回数としては、熱電併給装置１の特性や希望する耐用年数などによって適宜所望の回数を設定すれば良い。例えば、希望する耐用年数が１０年であれば３回程度に、そして、スタータ等の交換を考慮すれば６回程度に設定する、といった具合である。なお、この構成は、第２、第３、第４および第５実施例にも同様に適用できる。
【０１３７】
上記第１、第２、第３、第４、第５および第６実施例それぞれにおけるシステムからの放熱量ｅｘ（ｔ’）は、蓄熱タンク２、配管および熱電併給装置１の筐体からの放熱量ＳＴ（ｔ），ＰＬ（ｔ），ＧＥ（ｔ）を含み、いずれも、主としてシステム構築時の規模に比例した熱容量によって決まるものである。例えば、配管や熱電併給装置１の筐体や蓄熱タンク２を断熱材で覆うような構成を採用すれば、その放熱量を抑えることができるが、断熱材の断熱効果もシステム構築時に予め特定できるものであり、いずれにしても、配管や熱電併給装置１の筐体や蓄熱タンク２からの放熱量は、実験や計算や学習効果などによって予め特定できるものである。
【０１３８】
また、初期蓄熱量Ｓ（０）は、予め特定される電力需要と熱需要とに基づいて適宜設定されるものであり、予め特定できるものである。表−１に基づけば、初期蓄熱量は2,000［×(1/860)kW］である。
【０１３９】
本発明は、家庭用や製造工場や商用ビルなどの各種の用途のコージェネレーションシステムに適用できる。
【０１４０】
【発明の効果】
以上の説明から明らかなように、請求項１および請求項２に係る発明のコージェネレーションシステムの運転方法によれば、電力需要が定格発電量よりも小さいときの電力需要を越える余剰の電力を電熱変換手段によって熱に変換し、熱電併給装置を定格発電量で運転して発電するから、定格発電量よりも小さい発電量で運転する場合に比べて見掛け上の発電効率を高くできる。
しかも、例えば、１日などの１周期内にとどまらず、翌日の午前分の熱需要など次の１周期内の熱需要の一部を賄うために消費することを許容し、蓄熱タンクに貯めた熱が消費までの間に放熱する分と、不足分の電力を買電手段で賄うことと、変換した熱や熱電併給装置で発生した熱や蓄熱タンクに貯めた熱量で熱需要を賄うのに不足するときに不足分の熱を補助加熱手段で補うことをも考慮して、全体の一次エネルギーへの変換値が最小となるように運転するから、蓄熱タンクの容量の制約に起因してわずかな熱量不足を生じても、補助加熱手段の利用により良好に対処でき、放熱ロスのより少ない状態を選択して熱電併給装置を運転でき、省エネルギー性を良好に向上できる。
【０１４１】
また、請求項３および請求項４に係る発明のコージェネレーションシステムの運転方法によれば、電力需要が定格発電量を越えるときは熱電併給装置を定格発電量で運転して発電するから発電効率を高くでき、また、電力需要が定格発電量よりも小さいときは熱電併給装置を電力需要に追従して運転して発電し、余剰電力を発生させないようにするから、常時定格発電量で運転するよりも効率を向上できるとともに熱に変換するための構成を不用にできる。
しかも、例えば、１日などの１周期内にとどまらず、翌日の午前分の熱需要など次の１周期内の熱需要の一部を賄うために消費することを許容し、蓄熱タンクに貯めた熱が消費までの間に放熱する分と、不足分の電力を買電手段で賄うことと、変換した熱や熱電併給装置で発生した熱や蓄熱タンクに貯めた熱量で熱需要を賄うのに不足するときに不足分の熱を補助加熱手段で補うことをも考慮して、全体の一次エネルギーへの変換値が最小となるように運転するから、蓄熱タンクの容量の制約に起因してわずかな熱量不足を生じても、補助加熱手段の利用により良好に対処でき、放熱ロスのより少ない状態を選択して熱電併給装置を運転でき、省エネルギー性を良好に向上できる。
【０１４２】
また、請求項５および請求項６に係る発明のコージェネレーションシステムの運転方法によれば、熱電併給装置を複数段に設定した発電量で運転するから、常時一定出力で運転するよりも余剰電力が少なく効率良い運転ができる。
しかも、例えば、１日などの１周期内にとどまらず、翌日の午前分の熱需要など次の１周期内の熱需要の一部を賄うために消費することを許容し、蓄熱タンクに貯めた熱が消費までの間に放熱する分と、不足分の電力を買電手段で賄うことと、変換した熱や熱電併給装置で発生した熱や蓄熱タンクに貯めた熱量で熱需要を賄うのに不足するときに不足分の熱を補助加熱手段で補うことをも考慮して、全体の一次エネルギーへの変換値が最小となるように運転するから、蓄熱タンクの容量の制約に起因してわずかな熱量不足を生じても、補助加熱手段の利用により良好に対処でき、放熱ロスのより少ない状態を選択して熱電併給装置を運転でき、省エネルギー性を良好に向上できる。
【０１４３】
また、請求項７および請求項８に係る発明のコージェネレーションシステムの運転方法によれば、電力需要が定格発電量よりも小さいときの電力需要を越える余剰の電力を売電手段によって第３者に売り、熱電併給装置を定格発電量で運転して発電するから、定格発電量よりも小さい発電量で運転する場合に比べて見掛け上の発電効率を高くできる。
しかも、例えば、１日などの１周期内にとどまらず、翌日の午前分の熱需要など次の１周期内の熱需要の一部を賄うために消費することを許容し、蓄熱タンクに貯めた熱が消費までの間に放熱する分と、不足分の電力を買電手段で賄うことと、余剰の電力を売電手段によって第３者に売ること、ならびに、熱電併給装置で発生した熱や蓄熱タンクに貯めた熱量で熱需要を賄うのに不足するときに不足分の熱を補助加熱手段で補うことをも考慮して、全体の一次エネルギーへの変換値が最小となるように運転するから、蓄熱タンクの容量の制約に起因してわずかな熱量不足を生じても、補助加熱手段の利用により良好に対処でき、放熱ロスのより少ない状態を選択して熱電併給装置を運転でき、省エネルギー性を良好に向上できる。
【０１４４】
また、請求項９および請求項１０に係る発明のコージェネレーションシステムの運転方法によれば、熱電併給装置を複数段に設定した発電量で運転するから、常時一定出力で運転するよりも余剰電力が少なく効率良い運転ができる。
しかも、例えば、１日などの１周期内にとどまらず、翌日の午前分の熱需要など次の１周期内の熱需要の一部を賄うために消費することを許容し、蓄熱タンクに貯めた熱が消費までの間に放熱する分と、不足分の電力を買電手段で賄うことと、余剰の電力を売電手段によって第３者に売ること、ならびに、熱電併給装置で発生した熱や蓄熱タンクに貯めた熱量で熱需要を賄うのに不足するときに不足分の熱を補助加熱手段で補うことをも考慮して、全体の一次エネルギーへの変換値が最小となるように運転するから、蓄熱タンクの容量の制約に起因してわずかな熱量不足を生じても、補助加熱手段の利用により良好に対処でき、放熱ロスのより少ない状態を選択して熱電併給装置を運転でき、省エネルギー性を良好に向上できる。
【０１４５】
また、請求項１１に係る発明のコージェネレーションシステムの運転方法によれば、使用する熱電併給装置個々の特性や希望する耐用年数などに応じて、その発停回数を設定し、必要以上の発停の繰り返しを回避し、熱電併給装置の寿命が早期に低下することを防止して耐久性を向上できる。
【図面の簡単な説明】
【図１】本発明の第１実施例に係るコージェネレーションシステムを示すシステム構成図である。
【図２】ブロック図である。
【図３】実施例の説明に供する電力需要の経時的変化を示すグラフである。
【図４】実施例の説明に供する熱需要の経時的変化を示すグラフである。
【図５】第１実施例の動作説明に供する参考図であり、（ａ）および（ｃ）は、それぞれ電力需要と発電量との相関を示し、（ｂ）および（ｄ）は、それぞれ熱需要と発生熱量との相関を示している。
【図６】（ａ）、（ｂ）、（ｃ）および（ｄ）は、それぞれ運転停止状態と運転状態との組み合わせ例を示すタイムチャートである。
【図７】第１実施例の最適運転状態を例示するグラフであり、（ａ）は電力需要と発電量との相関を示し、（ｂ）は熱需要と発生熱量との相関を示している。
【図８】第２実施例の動作説明に供する参考図であり、（ａ）および（ｃ）は、それぞれ電力需要と発電量との相関を示し、（ｂ）および（ｄ）は、それぞれ熱需要と発生熱量との相関を示している。
【図９】第２実施例の最適運転状態を例示するグラフであり、（ａ）は電力需要と発電量との相関を示し、（ｂ）は熱需要と発生熱量との相関を示している。
【図１０】第３実施例の動作説明に供する参考図であり、（ａ）および（ｃ）は、それぞれ電力需要と発電量との相関を示し、（ｂ）および（ｄ）は、それぞれ熱需要と発生熱量との相関を示している。
【図１１】第３実施例の最適運転状態を例示するグラフであり、（ａ）は電力需要と発電量との相関を示し、（ｂ）は熱需要と発生熱量との相関を示している。
【図１２】本発明の第４実施例に係るコージェネレーションシステムを示すシステム構成図である。
【図１３】第４実施例のブロック図である。
【図１４】第６実施例のブロック図である。
【符号の説明】
１…熱電併給装置
２…蓄熱タンク
８…電熱変換手段としての電気ヒータ
１９…買電手段
２１…補助加熱手段としてのガスボイラ
２３…需要変化特定手段
３３…売電手段
４１…発停回数設定手段[0001]
BACKGROUND OF THE INVENTION
The present invention provides an operation of a cogeneration system configured to provide both electric power and heat by providing a cogeneration device that generates electric power and heat, such as an integrated engine and generator or a fuel cell. Regarding the method.
[0002]
[Prior art]
As this kind, there was one that was configured to follow the power demand, but if the total amount of heat generated by the combined heat and power unit is more than necessary, the excess heat is discarded It is useless.
[0003]
Therefore, a heat storage tank for storing the heat generated by the combined heat and power supply device is provided, temperature sensors are provided at predetermined locations above and below the heat storage tank, and the heat storage tank is full or almost empty based on the temperature change. The operation of the combined heat and power supply device is controlled to meet the heat demand.
[0004]
[Problems to be solved by the invention]
However, even when heat is not actually needed, heat is stored in the heat storage tank, and if the time until the stored heat is consumed is long, the amount of heat released from the heat storage tank increases, and this heat loss is reduced. For this reason, there is a drawback that the energy saving performance is lowered.
[0005]
As the operation mode, there are operation at the rated power generation amount, operation following the power demand for the portion below the rating, and further operation with multiple power generation amounts, but in either case, in order to reduce the heat dissipation loss, If you try to operate a combined heat and power supply device so that the time until heat is consumed is short, the power generation is reduced when the demand for power is low, and the apparent power generation efficiency or power generation efficiency decreases, saving energy. However, there is a problem of lowering.
[0006]
On the contrary, if the power generation efficiency is emphasized and the cogeneration apparatus is operated in a state where the power generation efficiency is high, there is a problem that the energy saving performance is reduced due to the heat radiation loss as described above.
[0007]
In addition, when constructing a cogeneration system, the heat storage tank must be limited in terms of capacity in terms of site area, heat insulation configuration, etc., and the amount of heat storage is limited, resulting in a slight lack of heat. In other words, there is a drawback in that energy saving performance is reduced, such as the operation of a combined heat and power supply device.
[0008]
  The present invention has been made in view of such circumstances, and claims 1, Claim 2, Claim 7And claims8The invention according to the invention makes it possible to improve the energy saving performance by operating the combined heat and power supply device in a state in which the apparent power generation efficiency is increased as much as possible and the heat radiation loss is reduced as much as possible, and the auxiliary heating means is used. Claims3, claim 4, claim 5, claim 6, claim 9And claims10An object of the present invention is to operate a combined heat and power supply device with the power generation efficiency as high as possible and the heat dissipation loss as small as possible, and to make it possible to improve the energy saving performance by using auxiliary heating means. And claims11An object of the invention is to improve durability.
[0009]
[Means for Solving the Problems]
  In order to achieve the above-described object, the operation method of the cogeneration system of the invention according to claim 1
  A combined heat and power generation device that generates the rated amount of power and heat;
  A heat storage tank for storing heat generated by the cogeneration device;
  Electrothermal conversion means for converting the electric power generated in the cogeneration device into heat;
  Auxiliary heating means to compensate for the shortage of heat,
  Demand change specifying means for predetermining changes with time of each of heat demand and power demand within one cycle, with a predetermined time as one cycle;
  Power purchase means capable of supplying insufficient power,
  The amount of heat corresponding to the heat demand in the one cycle or most of it is generated and consumed in the one cycle by the combined heat and power supply device, and the excess heat is consumed in the next cycle. Allowing and supplementing the deficient amount of heat with the auxiliary heating means, dividing the one cycle into set time intervals, and assuming a state in which the combined heat and power supply device is operated and a state in which it is stopped at each divided time Then, the amount of heat stored in the heat storage tank is not less than 0 and does not exceed the maximum amount of heat stored, and the optimum operating state of the combination that minimizes the converted value of the overall primary energy is obtained, and depending on the obtained optimum operating state The heat and power supply device is operated with a rated power generation amount, and surplus power when the power demand is smaller than the power of the rated power generation amount is converted into heat by the electrothermal conversion means.
  Moreover, in order to achieve the above object, the operation method of the cogeneration system of the invention according to claim 2
  In the operation method of the cogeneration system according to claim 1,
  Demand change specifying means for predetermining temporal changes of heat demand and electric power demand within one period T with a predetermined time as one period TBe equippede,
  The amount of heat corresponding to the heat demand in the one cycle T or most of the heat is generated and consumed in the one cycle T by the combined heat and power supply device, and excess heat is consumed in the next cycle. And the supplementary heating means compensates for the shortage of heat, divides the one period T into set time intervals d, and stops the state in which the combined heat and power device is operated at each divided time. Assuming the state, the fluctuation value S (t + n · d) of the heat storage amount in the heat storage tank always satisfies the following conditional expression (1), and the converted value PE [Expression (4)] of the following primary energy is minimum. The combined operation of the thermoelectric power supply device is operated at the rated power generation amount according to the determined optimal operation state, and surplus power when the power demand is smaller than the power of the rated power generation amount is calculated by the electrothermal conversion means. It is characterized by converting the.
[30]

  Here, S [t + (n−1) d] indicates the amount of heat stored in the heat storage tank at the start of operation for each divided time. In addition, n is a positive integer of 1 to T / d, h (t ′) is a function indicating a temporal change in heat demand specified in advance, and ex (t ′) is a release from the system. The amount of heat. S_max Indicates the maximum amount of heat stored in the heat storage tank.
  HT_n Indicates the amount of heat obtained within the divided time interval d, and is expressed by the following equation (2).
[31]

  Here, F indicates the power of the rated power generation amount, and k indicates the thermoelectric ratio. H_nIs the amount of heat converted from surplus power to heat by the electrothermal conversion means, F> E_n The amount of (t ′) is integrated and is expressed by the following equation (3).
[Expression 32]

  However, if e (t ′) <F, E_n (T ′) = e (t ′)
        If e (t ′) ≧ F, E_n (T ′) = F
  Where E_n (T ′) is the rated power amount when the load power exceeds the rated power generation amount, and is the power amount that becomes the load power amount when the load power is smaller than the rated power, and e (t ′) is It is a function which shows a time-dependent change of the electric power demand (load electric power) specified beforehand.
  In the above equation (2), BO (t ′) represents a function in the case where the auxiliary heating means is activated so as to compensate for the shortage when the shortage of heat occurs.
  PE = ΣPE_n = ΣGI_n ・ Α + ΣBI_n ・ Α ’＋ ΣBE_n ・ Β …… (4)
  Where ΣPE_n Is the sum of the primary energies of n = 1 to T / d. GI_nIs a fuel supply amount required for the operation of the combined heat and power supply device, and is expressed by the following equation (5), and α is a converted value to the primary energy of the fuel, and ΣGI_n Α is the sum of n = 1 to T / d. Also, BI_n Is the fuel supply amount required for the operation of the auxiliary heating means, α ′ is the converted value of the fuel into the primary energy, and ΣBI_n Α ′ is the sum of n = 1 to T / d.
[Expression 33]

  Here, GI (t ′) is a fuel supply amount specified by the combined heat and power supply device to be used.
  ΣBE_n Is an input amount of insufficient power within a predetermined time T that is one cycle T, and is expressed by the following equation (6), and β is a converted value of the power to primary energy, and n = 1 The total of ~ T / d is obtained.
[Expression 34]

  Here, GP is the power generation amount of the combined heat and power supply device, and is expressed by the following equation (7).
[Expression 35]

  Here, E (t ′) is the rated power amount when the load power exceeds the rated power generation amount, and is the power amount that becomes the load power amount when the load power is smaller than the rated power.
[0010]
  Claims3In order to achieve the above-described object, the operation method of the cogeneration system of the invention according to
  A cogeneration device that generates power and heat that can be operated according to the load power when the load power is less than the rated power generation amount,
  A heat storage tank for storing heat generated by the cogeneration device;
  Auxiliary heating means to compensate for the shortage of heat,
  Demand change specifying means for predetermining changes with time of each of heat demand and power demand within one cycle, with a predetermined time as one cycle;
  Power purchase means capable of supplying insufficient power,
  The amount of heat corresponding to the heat demand in the one cycle is generated and consumed in the one cycle by the combined heat and power supply device, and the excess heat is allowed to be consumed in the next cycle, And, supplement the shortage of heat with the auxiliary heating means, dividing the one cycle for each set time interval, assuming a state of operating the combined heat and power unit and a state of stopping at each divided time, An optimum operating state of a combination that minimizes the converted value of the primary energy is determined so that the amount of heat stored in the heat storage tank is 0 or more and does not exceed the maximum amount of stored heat, and the thermoelectric power is calculated according to the obtained optimum operating state. The cogeneration apparatus is operated with the rated power generation amount, and when the power demand is smaller than the power of the rated power generation amount, the cooperating device is operated following the change in the power demand.
  Further, the operation method of the cogeneration system of the invention according to claim 4 is to achieve the above-described object,
  A predetermined time is defined as one period T, and a demand change specifying means for specifying in advance a temporal change in each of the heat demand and power demand within the period T.StepPrepared,
  The amount of heat corresponding to the heat demand within one cycle T is generated and consumed within the one cycle T by the combined heat and power supply device, and excess heat is allowed to be consumed in the next cycle. And supplementing the deficient amount of heat with the auxiliary heating means, dividing the one period T into set time intervals d, and operating and stopping the combined heat and power device at each divided time. Assuming that the variation value S (t + n · d) of the heat storage amount in the heat storage tank always satisfies the following conditional expression (8), and the following primary energy conversion value PE [Expression (10)] is minimized. Obtain the optimum operating state, and operate the combined heat and power supply device with the rated power generation amount according to the determined optimum operating state and follow the change in the power demand when the power demand is smaller than the rated power generation amount. It is characterized.
[Expression 36]

  Here, S [t + (n−1) d] indicates the amount of heat stored in the heat storage tank at the start of operation for each divided time. In addition, n is a positive integer of 1 to T / d, h (t ′) is a function indicating a temporal change in heat demand specified in advance, and ex (t ′) is a release from the system. The amount of heat. Smax indicates the maximum heat storage amount of the heat storage tank.
  HTn represents the amount of heat acquired within the divided time interval d, and is expressed by the following equation (9).
[Expression 37]

  Here, En (t ′) is the amount of electric power that becomes the rated electric energy when the load electric power exceeds the electric power of the rated electric power generation, and the electric energy that becomes the electric power of the load when the electric power is smaller than the rated electric power. B [En (t ')] indicates the amount of heat generated by the combined heat and power device at the amount of power En (t').
  BO (t ′) represents a function in the case where the auxiliary heating means is activated so as to compensate for the shortage when the shortage of heat occurs.
  PE = ΣPEn = ΣGIn · α + ΣBIn · α '+ ΣBEn · β (10) where ΣPEn is the total primary energy of n = 1 to T / d. GIn is a fuel supply amount required for the operation of the combined heat and power supply device, and is expressed by the following equation (5a), α is a converted value to the primary energy of fuel, and ΣGIn · α is n = 1 to T / d Seeking the sum of BIn is a fuel supply amount required for the operation of the auxiliary heating means, α ′ is a converted value to the primary energy of the fuel, and ΣBIn · α ′ is a sum of n = 1 to T / d.
[Formula 38]

  Here, GI (t ′) is a fuel supply amount specified by the combined heat and power supply device to be used.
  ΣBE n is an input amount of insufficient power within a predetermined time T that is one cycle T, and is expressed by the following equation (11), and β is a converted value of power to primary energy, and n = The sum of 1 to T / d is obtained.
[39]

  Here, GP is a power generation amount of the combined heat and power supply device, and is represented by the following equation (12).
[Formula 40]

  Here, E (t ′) is the rated power amount when the load power exceeds the power of the rated power generation amount, and is the power amount that becomes the load power amount when the load power is smaller than the rated power, and e (t ') Is a function indicating a change with time in power demand (load power) specified in advance.
[0011]
  Claims5In order to achieve the above-described object, the operation method of the cogeneration system of the invention according to
  A combined heat and power device that operates with the power generation amount set in multiple stages and generates the power and heat of the set power generation amount,
  A heat storage tank for storing heat generated by the cogeneration device;
  Electrothermal conversion means for converting the electric power generated in the cogeneration device into heat;
  Auxiliary heating means to compensate for the shortage of heat,
  Demand change specifying means for predetermining temporal changes in heat demand and power demand in each of the one period and the next one period, with a predetermined time as one period,
  Power purchase means capable of supplying insufficient power,
  The amount of heat corresponding to the heat demand in the one cycle is generated and consumed in the one cycle by the combined heat and power supply device, and the excess heat is allowed to be consumed in the next cycle, In addition, the amount of heat that is insufficient is supplemented by the auxiliary heating means, and the one cycle is divided every set time interval, and the combined heat and power unit is operated at each of the divided power generation amounts and stopped at each divided time. Assuming that the heat storage amount in the heat storage tank is 0 or more and does not exceed the maximum heat storage amount, the optimum operating state of the combination that minimizes the converted value of the overall primary energy is obtained and obtained. According to the optimum operating state, the combined heat and power device is operated with a plurality of stages of rated power generation amount, and surplus power when the power demand is smaller than a set power generation amount is converted into heat by the electrothermal conversion means. To have.
  In order to achieve the above-mentioned object, the operation method of the cogeneration system of the invention according to claim 6
  In the operation method of the cogeneration system according to claim 5,
  A predetermined period of time is defined as one period T, and a demand change specifying method for specifying in advance a temporal change in each of the heat demand and power demand in each of the one period T and the next one period T.StepPrepared,
  A combined heat and power device that operates with the power generation amount set in multiple stages and generates the power and heat of the set power generation amount,
  A heat storage tank for storing heat generated by the cogeneration device;
  Electrothermal conversion means for converting the electric power generated in the cogeneration device into heat;
  Auxiliary heating means to compensate for the shortage of heat,
  Suppose that a predetermined time is one period T, a demand change specifying means for specifying in advance a temporal change in each of the heat demand and the power demand in each of the one period T and the next one period T, and a purchase capable of supplying insufficient power Electric means,
  The amount of heat corresponding to the heat demand within one cycle T is generated and consumed within the one cycle T by the combined heat and power supply device, and excess heat is allowed to be consumed in the next cycle. In addition, the shortage of heat is supplemented by the auxiliary heating means, and the one cycle T is divided every set time interval d, and the combined heat and power unit is operated at each of the set power generation amounts in a plurality of stages at each divided time. Assuming a state to be stopped and a state to be stopped, the fluctuation value S (t + n · d) of the heat storage amount in the heat storage tank always satisfies the following conditional expression (13), and the converted value PE of the following primary energy [Expression (16 )] Is determined as the optimum operating state of the combination that minimizes the surplus power when the combined heat and power unit is operated with the rated power generation amount in a plurality of stages and the power demand is smaller than the set power generation amount according to the obtained optimum operating state Is characterized by converting into heat by said electrothermal converter.
[Expression 41]

  Here, S [t + (n−1) d] indicates the amount of heat stored in the heat storage tank at the start of operation for each divided time. In addition, n is a positive integer of 1 to T / d, h (t ′) is a function indicating a temporal change in heat demand specified in advance, and ex (t ′) is a release from the system. The amount of heat. S_max Indicates the maximum amount of heat stored in the heat storage tank.
  HT_n Indicates the amount of heat obtained within the divided time interval d, and is expressed by the following equation (14).
[Expression 42]

  Where F_m Is the set power generation amount, k_m Is the set power generation amount F_m The thermoelectric ratios at are shown respectively. m is a positive integer greater than or equal to 2 and up to the set number of power generation levels. H_nIs the amount of heat converted from surplus power to heat by the electrothermal conversion means, F_m > E_n The amount of (t ′) is integrated and is expressed by the following equation (15).
[Expression 43]

  However, e (t ′) <F_m If so, E_n (T ′) = e (t ′)
        e (t ′) ≧ F_m If so, E_n (T ′) = F_m
  Where E_n (T '), the load power is the set power generation amount F_m Exceeds the set power amount, and the load power is the set power generation amount F._m When it is smaller, it is the amount of power that becomes the load power amount, and e (t ′) is a function that indicates a change in power demand (load power) specified in advance over time.
  In the above equation (14), BO (t ′) represents a function in the case where the auxiliary heating means is activated so as to compensate for the shortage when the shortage of heat occurs.
  PE = ΣPE_n = ΣGI_n ・ Α + ΣBI_n ・ Α ’＋ ΣBE_n ・ Β …… (16)
  Where ΣPE_n Is the sum of the primary energies of n = 1 to T / d. GI_nIs a fuel supply amount required for the operation of the combined heat and power supply device, and is expressed by the following equation (17), and α is a converted value to the primary energy of the fuel, and ΣGI_n Α is the sum of n = 1 to T / d. Also, BI_n Is the fuel supply amount required for the operation of the auxiliary heating means, α ′ is the converted value of the fuel into the primary energy, and ΣBI_n Α ′ is the sum of n = 1 to T / d.
(44)

  Here, GI (t ′) is a fuel supply amount specified by the combined heat and power supply device to be used.
  ΣBE_n Is an input amount of insufficient power within a predetermined time T that is one cycle T, and is expressed by the following equation (18), and β is a converted value of the power to primary energy, and n = 1 The total of ~ T / d is obtained.
[Equation 45]

  Here, GP is a power generation amount of the combined heat and power supply device, and is represented by the following equation (19).
[Equation 46]

  Here, E (t ′) becomes the set power amount when the load power exceeds the set power generation amount Fm, and the load power becomes the set power generation amount F._m If it is smaller, it is the amount of power that becomes the load power amount.
[0012]
  Claims7In order to achieve the above-described object, the operation method of the cogeneration system of the invention according to
  A combined heat and power generation device that generates the rated amount of power and heat;
  A heat storage tank for storing heat generated by the cogeneration device;
  A power selling means for selling the electric power generated by the cogeneration device to a third party;
  Auxiliary heating means to compensate for the shortage of heat,
  Demand change specifying means for predetermining changes with time of each of heat demand and power demand within one cycle, with a predetermined time as one cycle;
  Power purchase means capable of supplying insufficient power,
  The amount of heat corresponding to the heat demand in the one cycle or most of it is generated and consumed in the one cycle by the combined heat and power supply device, and the excess heat is consumed in the next cycle. Allowing and supplementing the deficient amount of heat with the auxiliary heating means, dividing the one cycle into set time intervals, and assuming a state in which the combined heat and power supply device is operated and a state in which it is stopped at each divided time And determining the optimum operating state of the combination that minimizes the converted value of the total primary energy so that the fluctuation value of the heat storage amount in the heat storage tank is not less than 0 and does not exceed the maximum heat storage amount. According to the operation state, the combined heat and power supply device is operated at a rated power generation amount, and surplus power when the power demand is smaller than the power of the rated power generation amount is sold to a third party by the power selling means.
  Further, the operation method of the cogeneration system of the invention according to claim 8 is to achieve the above-described object,
  A predetermined time is defined as one period T, and a demand change specifying means for specifying in advance a temporal change in each of the heat demand and power demand within the period T.StepPrepared,
  The amount of heat corresponding to the heat demand in the one cycle T or most of the heat is generated and consumed in the one cycle T by the combined heat and power supply device, and excess heat is consumed in the next cycle. And the supplementary heating means compensates for the shortage of heat, divides the one period T into set time intervals d, and stops the state in which the combined heat and power device is operated at each divided time. Assuming the state, the fluctuation value S (t + n · d) of the heat storage amount in the heat storage tank always satisfies the following conditional expression (20), and the converted value PE of the following primary energy [Expression (22)] is minimum. The combined operation of the combined heat and power unit is operated at the rated power generation amount, and surplus power when the power demand is smaller than the rated power generation power is It is characterized in that sell to the third party.
[Equation 47]

  Here, S [t + (n−1) d] indicates the amount of heat stored in the heat storage tank at the start of operation for each divided time. In addition, n is a positive integer of 1 to T / d, h (t ′) is a function indicating a temporal change in heat demand specified in advance, and ex (t ′) is a release from the system. The amount of heat. Smax indicates the maximum heat storage amount of the heat storage tank.
  HTn represents the amount of heat acquired within the divided time interval d, and is expressed by the following equation (21).
[Formula 48]

  Here, F indicates the power of the rated power generation amount, and k indicates the thermoelectric ratio.
  In the above equation (21), BO (t ′) represents a function when the auxiliary heating means is activated so as to compensate for the shortage when a shortage of heat occurs.
PE = ΣPEn
    = ΣGI n · α + ΣBI n · α '+ ΣBE n · β-ΣSE n · γ (22)
  Here, ΣPEn is the total primary energy of n = 1 to T / d. GIn is a fuel supply amount required for the operation of the combined heat and power supply device, and is expressed by the following equation (23), α is a converted value to the primary energy of the fuel, and ΣGIn · α is n = 1 to T / d. Seeking the sum of BIn is a fuel supply amount required for the operation of the auxiliary heating means, α ′ is a converted value to the primary energy of the fuel, and ΣBIn · α ′ is a sum of n = 1 to T / d.
[Equation 49]

  Here, GI (t ′) is the fuel supply amount specified by the combined heat and power supply device to be used, and becomes zero in the operation stop state.
  ΣBE n is an input amount of insufficient power within a predetermined time T, which is one cycle T, and is expressed by the following equation (24), and β is a converted value of power to primary energy, and n = The sum of 1 to T / d is obtained.
[Equation 50]

  Here, GP is the power generation amount of the combined heat and power supply device, and is represented by the following equation (25).
[Equation 51]

  Here, E (t ′) is the rated power amount when the load power exceeds the rated power generation amount, and is the power amount that becomes the load power amount when the load power is smaller than the rated power. Further, ΣSEn is the surplus electric energy sold to the third party by the power selling means, and is integrated by F> En (t ′), and is expressed by the following equation (26), and γ is the third party. This is a conversion value obtained by converting the price when selling to 1 to primary energy, and the sum of n = 1 to T / d is obtained.
[Formula 52]

  However, if e (t ') <F, En (t') = e (t ')
        If e (t ') ≥F, En (t') = F
  Here, En (t ′) is the rated power amount when the load power exceeds the power of the rated power generation amount, and is the power amount that becomes the load power amount when the load power is smaller than the rated power, and e (t ') Is a function indicating a change with time in power demand (load power) specified in advance.
[0013]
  Claims9In order to achieve the above-described object, the operation method of the cogeneration system of the invention according to
  A combined heat and power device that operates with the power generation amount set in multiple stages and generates the power and heat of the set power generation amount,
  A heat storage tank for storing heat generated by the cogeneration device;
  A power selling means for selling the electric power generated by the cogeneration device to a third party;
  Auxiliary heating means to compensate for the shortage of heat,
  Demand change specifying means for predetermining temporal changes in heat demand and power demand in each of the one period and the next one period, with a predetermined time as one period,
  Power purchase means capable of supplying insufficient power,
  The amount of heat corresponding to the heat demand in the one cycle is generated and consumed in the one cycle by the combined heat and power supply device, and the excess heat is allowed to be consumed in the next cycle, In addition, the amount of heat that is insufficient is supplemented by the auxiliary heating means, and the one cycle is divided every set time interval, and the combined heat and power unit is operated at each of the divided power generation amounts and stopped at each divided time. Assuming that the heat storage amount in the heat storage tank is 0 or more and does not exceed the maximum heat storage amount, the optimum operating state of the combination that minimizes the converted value of the overall primary energy is obtained and obtained. According to the optimum operating state, the combined heat and power unit is operated with a plurality of stages of rated power generation amount, and surplus power when the power demand is smaller than the set power generation amount is sold to a third party by the power selling means. That.
  Moreover, in order to achieve the above-mentioned object, the operation method of the cogeneration system of the invention according to claim 10
  A predetermined period of time is defined as one period T, and a demand change specifying method for specifying in advance a temporal change in each of the heat demand and power demand in each of the one period T and the next one period T.StepPrepared,
  The amount of heat corresponding to the heat demand within one cycle T is generated and consumed within the one cycle T by the combined heat and power supply device, and excess heat is allowed to be consumed in the next cycle. In addition, the shortage of heat is supplemented by the auxiliary heating means, and the one cycle T is divided every set time interval d, and the combined heat and power unit is operated at each of the set power generation amounts in a plurality of stages at each divided time. Assuming the state of being stopped and the state of stopping, the fluctuation value S (t + n · d) of the heat storage amount in the heat storage tank always satisfies the following conditional expression (27), and the converted value PE of the following primary energy [Expression (29 )] Is determined as the optimum operating state of the combination that minimizes the surplus power when the combined heat and power unit is operated with the rated power generation amount in a plurality of stages and the power demand is smaller than the set power generation amount according to the determined optimum operating state. It is characterized in that sell to a third party by the power selling unit.
[Equation 53]

  Here, S [t + (n−1) d] indicates the amount of heat stored in the heat storage tank at the start of operation for each divided time. In addition, n is a positive integer of 1 to T / d, h (t ′) is a function indicating a temporal change in heat demand specified in advance, and ex (t ′) is a release from the system. The amount of heat. S_max Indicates the maximum amount of heat stored in the heat storage tank.
  HT_n Indicates the amount of heat obtained within the divided time interval d, and is expressed by the following equation (28).
[Formula 54]

  Where F_m Is the set power generation amount, k_mIs the set power generation amount F_m The thermoelectric ratios at are shown respectively. m is a positive integer greater than or equal to 2 and up to the set number of power generation levels.
  In the above equation (28), BO (t ′) represents a function when the auxiliary heating means is activated so as to compensate for the shortage when the shortage of heat occurs.
PE = ΣPE_n
    = ΣGI_n ・ Α + ΣBI_n ・ Α ’＋ ΣBE_n ・ Β-ΣSE_n ・ Γ… (29)
  Where ΣPE_n Is the sum of the primary energies of n = 1 to T / d. GI_nIs a fuel supply amount required for the operation of the combined heat and power supply device, and is expressed by the following equation (30), and α is a converted value to the primary energy of the fuel, and ΣGI_n Α is the sum of n = 1 to T / d. Also, BI_n Is the fuel supply amount required for the operation of the auxiliary heating means, α ′ is the converted value of the fuel into the primary energy, and ΣBI_n Α ′ is the sum of n = 1 to T / d.
[Expression 55]

  Here, GI (t ′) is the fuel supply amount specified by the combined heat and power supply device to be used, and becomes zero in the operation stop state.
  ΣBE_n Is an input amount of insufficient power within a predetermined time T that is one cycle T, and is expressed by the following equation (31), and β is a converted value of the power to primary energy, and n = 1 The total of ~ T / d is obtained.
[56]

  Here, GP is the power generation amount of the combined heat and power supply device, and is represented by the following equation (32).
[Equation 57]

  Here, E (t ′) is the rated power amount when the load power exceeds the rated power generation amount, and is the power amount that becomes the load power amount when the load power is smaller than the rated power. Also, ΣSE_n Is the amount of surplus power sold to third parties by means of power selling, F> E_n (T ′) is integrated and is expressed by the following equation (33), and γ is a converted value obtained by converting the price when selling to a third party into primary energy, and n = 1 to The total sum of T / d is obtained.
[Formula 58]

  However, e (t ′) <F_m If so, E_n (T ′) = e (t ′)
        e (t ′) ≧ F_m If so, E_n (T ′) = F
  Where E_n (T '), the load power is the set power generation amount F_m If the load power exceeds the set power generation amount Fm, the load power amount is the power amount that becomes the load power amount, and e (t ′) is the time of the power demand (load power) specified in advance. It is a function that shows the change.
[0014]
  Claims11In order to achieve the above-described object, the invention according to
  Claim 1, Claim 2, Claim 3, Claim 4, Claim 5, Claim 6, claim 7, claim 8, claim 9, and claim 10In the operation method of the cogeneration system according to any one of
  A combination that includes a start / stop number setting means for setting the number of start / stops in one cycle of the combined heat and power device, and the conversion value PE of the primary energy is minimized when the number of start / stops in one cycle of the thermoelectric combined device is equal to or less than the set number. The optimum operation state is determined.
[0015]
[Action]
  Claim 1And claim 2According to the configuration of the operation method of the cogeneration system according to the invention, for example, within a predetermined period of time such as one day, the cogeneration system is operated with the rated power generation amount to generate power, and the power demand is rated power generation. The surplus power that exceeds the power demand when it is smaller than the amount of power is converted into heat by the electrothermal conversion means, and the shortage power is covered by the power purchase means, and the heat is generated by the converted heat and the heat generated by the combined heat and power supply device. It is possible to cover the demand and store the heat necessary later in the heat storage tank to meet the heat demand, and supplement the insufficient heat with the auxiliary heating means.
  At this time, for example, it is allowed not to stay within one cycle such as one day, but to consume part of the heat demand within the next one cycle such as the morning or daytime heat demand of the next day, The heat stored in the heat storage tank is dissipated from the system until it is consumed, etc., and the shortage of electricity is covered by the power purchase means, and the converted heat and heat generated from the combined heat and power storage tank In consideration of supplementing the shortage of heat with auxiliary heating means when it is insufficient to cover the heat demand with the amount of heat stored in the battery, one cycle is divided at set time intervals, and a combined heat and power unit for each divided time The amount of heat stored in the heat storage tank is0 or moreAnd do not exceed the maximum heat storage amount,In the case of the invention according to claim 22 (T / d) powerAnd so onA combination of virtual operating states is obtained, and based on the combination, a combination that minimizes the conversion value to the total primary energy is obtained, and operation is performed according to the combination.
[0016]
  Claims3 and claim 4According to the configuration of the operation method of the cogeneration system according to the invention, for example, when the power demand exceeds the rated power generation amount within a predetermined period of one cycle such as one day, the cogeneration system is operated at the rated power generation amount. If the power demand is smaller than the rated power generation amount, the combined heat and power supply is operated to follow the power demand to generate power, and the shortage of power is covered by the power purchase means and the heat generated by the combined heat and power supply Thus, the heat demand can be covered and the heat required later can be stored in the heat storage tank to meet the heat demand, and the deficient heat can be supplemented by the auxiliary heating means.
  At this time, for example, it is allowed not to stay within one cycle such as one day, but to consume part of the heat demand within the next one cycle such as the morning or daytime heat demand of the next day, The amount of heat stored in the heat storage tank is dissipated before consumption and the shortage of electricity is covered by the electricity purchase means, and the converted heat, the heat generated by the combined heat and power unit, and the heat stored in the heat storage tank Considering supplementing the shortage of heat with auxiliary heating means when it is insufficient to cover demand, the cycle is divided at set time intervals and the combined heat and power unit is operated and stopped for each divided time The amount of heat stored in the heat storage tank0 or moreAnd do not exceed the maximum heat storage amount,In the case of the invention according to claim 42 (T / d) powerAnd so onA combination of virtual operating states is obtained, and based on the combination, a combination that minimizes the conversion value to the total primary energy is obtained, and operation is performed according to the combination.
[0017]
  Claims5 and claim 6According to the configuration of the operation method of the cogeneration system according to the present invention, for example, within a predetermined time that is one cycle, such as one day, the cogeneration system is operated with a power generation amount set in a plurality of stages to generate power. The surplus power that exceeds the power demand when the demand is less than the set power generation amount is converted into heat by the electrothermal conversion means, and the shortage of electricity is covered by the power purchase means, and generated by the converted heat and heat and power combined device It is possible to cover the heat demand with the heat generated and store the heat required later in the heat storage tank to meet the heat demand, and supplement the insufficient heat with the auxiliary heating means.
  At this time, for example, it is allowed not to stay within one cycle such as one day, but to consume part of the heat demand within the next one cycle such as the morning or daytime heat demand of the next day, The amount of heat stored in the heat storage tank is dissipated before consumption and the shortage of electricity is covered by the electricity purchase means, and the converted heat, the heat generated by the combined heat and power unit, and the heat stored in the heat storage tank In consideration of supplementing the shortage of heat with auxiliary heating means when it is insufficient to cover demand, one cycle is divided at set time intervals, and multiple heat and power supply devices are set for each division time The amount of heat stored in the heat storage tank is different depending on whether it is operating with power generation or stopped.0 or moreAnd do not exceed the maximum heat storage amount,In the case of the invention according to claim 6(1 + m) divided by (T / d)And so onA combination of virtual operating states is obtained, and based on the combination, a combination that minimizes the conversion value to the total primary energy is obtained, and operation is performed according to the combination.
[0018]
  Claims7 and claim 8According to the configuration of the operation method of the cogeneration system according to the invention, for example, within a predetermined period of time such as one day, the cogeneration system is operated with the rated power generation amount to generate power, and the power demand is rated power generation. The surplus power exceeding the power demand when it is smaller than the amount of power is sold to the third party by the power selling means, and the shortage of power is covered by the power buying means, and the heat demand is covered by the heat generated by the combined heat and power supply device. In addition, the heat required later can be stored in the heat storage tank to meet the heat demand, and the insufficient heat can be supplemented by the auxiliary heating means.
  At this time, for example, it is allowed not to stay within one cycle such as one day, but to consume part of the heat demand within the next one cycle such as the morning or daytime heat demand of the next day, Supply heat from the system such as the heat stored in the heat storage tank to dissipate before consumption, and supply the shortage of power with power purchase means, and sell surplus power to third parties with power sale means In addition, taking into account that the heat generated by the combined heat and power supply device and the amount of heat stored in the heat storage tank is insufficient to cover the heat demand, the supplementary heating means supplements the shortage of heat, so one cycle is set Divided at intervals, the amount of heat stored in the heat storage tank in each state where the combined heat and power unit is operated and stopped in each divided time0 or moreAnd do not exceed the maximum heat storage amount,In the case of the invention according to claim 82 (T / d) powerAnd so onA combination of virtual operating states is obtained, and based on the combination, a combination that minimizes the conversion value to the total primary energy is obtained, and operation is performed according to the combination.
[0019]
  Claims9 and claim 10According to the configuration of the operation method of the cogeneration system according to the present invention, for example, within a predetermined time that is one cycle, such as one day, the cogeneration system is operated with a power generation amount set in a plurality of stages to generate power. The surplus power exceeding the power demand when the demand is less than the set power generation amount is sold to a third party by the power selling means, and the shortage power is covered by the power buying means, and the converted heat and heat and power combined device The generated heat can cover the heat demand, and the heat required later can be stored in the heat storage tank to meet the heat demand, and the insufficient heat can be supplemented by the auxiliary heating means.
  At this time, for example, it is allowed not to stay within one cycle such as one day, but to consume part of the heat demand within the next one cycle such as the morning or daytime heat demand of the next day, The amount of heat stored in the heat storage tank is dissipated before consumption, and the shortage of power is covered by power purchase means, surplus power is sold to a third party by power sale means, and a combined heat and power supply device In consideration of supplementing the shortage of heat with auxiliary heating means when it is insufficient to cover the heat demand with the amount of heat generated in the tank or the amount of heat stored in the heat storage tank, one cycle is divided at set time intervals. The amount of heat stored in the heat storage tank in each of the state where the combined heat and power unit is operated with the power generation amount set in multiple stages and the state where it is stopped for each division time.0 or moreAnd do not exceed the maximum heat storage amount,In the case of the invention according to claim 10(1 + m) divided by (T / d)And so onA combination of virtual operating states is obtained, and based on the combination, a combination that minimizes the conversion value to the total primary energy is obtained, and operation is performed according to the combination.
[0020]
  Claims11According to the configuration of the operation method of the cogeneration system according to the invention, the number of times of starting and stopping is set according to the characteristics of each cogeneration device to be used, the desired service life, etc. To avoid.
[0021]
DETAILED DESCRIPTION OF THE INVENTION
Next, embodiments of the present invention will be described in detail with reference to the drawings.
FIG. 1 is a system configuration diagram showing a first embodiment of a cogeneration system, wherein 1 is a combined heat and power supply device, and 2 is a heat storage tank.
[0022]
A circulation pipe 4 having a first pump 3 is connected to the heat storage tank 2 from the bottom side to the top. A heat exchanger 5 is provided in the circulation pipe 4, and a heat recovery circulation pipe 7 including a second pump 6 is connected across the cogeneration apparatus 1 and the heat exchanger 5.
[0023]
With this configuration, the water taken out from the lower part of the heat storage tank 2 is heated by the heat from the combined heat and power supply device 1, and the heated heat storage water is returned to the heat storage tank 2 to store heat.
An electric heater 8 serving as an electrothermal conversion means is provided at a location downstream of the heat exchanger 5 in the circulation pipe 4, and when the electric power generated by the cogeneration apparatus 1 is surplus, the surplus power is converted into heat to store heat. The water taken out from the lower part of the tank 2 is heated, and the heated heat storage water can be stored in the heat storage tank 2. In the figure, reference numeral 9 denotes a hot water supply pipe for hot water supply.
[0024]
An output circulation pipe 10 is connected to the circulation pipe 4 in series with the heat exchanger 5, and a heating heat exchanger 11 is provided in the output circulation pipe 10. In addition, a heating device 14 for central heating, such as an indoor heater, a floor heater, and a bathroom dryer, is connected via a heating circulation pipe 13 provided with a third pump 12.
[0025]
A power line 15 for extracting generated power is connected to the combined heat and power supply apparatus 1, and an electric load 16 such as a lighting device or an electric device is connected to the power line 15. Further, a commercial power line 18 is connected to the power line 15 via a protection device 17 for preventing a reverse power flow, and a power purchase means 19 is configured so that power from the commercial power source can be input when the generated power is insufficient. .
[0026]
In addition, the electric heater 8 is connected to the power line 15 via the switch circuit 20, and the electric heater 8 is energized when surplus power is generated. The electric heater 8 may be provided in the heat recovery circulation pipe 7 as indicated by a two-dot chain line. In the figure, reference numeral 21 denotes a gas boiler as auxiliary heating means.
[0027]
A microcomputer 22 is connected to the cogeneration apparatus 1, the switch circuit 20, and the gas boiler 21.
As shown in the block diagram of FIG. 2, the microcomputer 22 includes a demand change specifying unit 23, an operation state input unit 24, a calculation unit 25, a comparison unit 26, and an operation control unit 27.
[0028]
In the demand change specifying means 23, as shown in the graphs of FIGS. 3 and 4, the power demand e (t ′) for driving the lighting device and the electrical equipment in one day as one cycle T, hot water supply and heating The time change of the heat demand h (t ′) such as is stored in advance by a learning function or the like, and the time change of the power demand e (t ′) and the heat demand h (t ′) can be specified in advance. ing. Table 1 shows numerical examples of changes over time of the heat demand h (t ′) such as the hot water supply and heating. 3 and 4 show an average value of a large number of consumers and show it as a schematic change.
[Table 1]

[0029]
That is, the change in demand on the previous day, the change in demand on the same day of the week before, and the like are sequentially stored, and based on these demand changes, the heat demand h (t ′) for the first day of the current day and the first day of the next day, and the power demand The change with time of e (t ′) can be specified in advance.
[0030]
In the operation state input means 24, one day as one period T is divided at a set time interval d, for example, every 30 minutes, and the combined heat and power supply apparatus 1 is operated at the rated power generation amount at each divided time d. And each state to stop is input.
[0031]
In the calculation means 25, the operation state and the stop state are input from the operation state input means 24 to a conditional expression or relational expression described later, the heat demand h (t ′) from the demand change specifying means 23 for one day on the day, and If the set time interval d is 30 minutes based on the change over time in the power demand e (t ′), the converted value of primary energy for each of the 2 48 power combinations is calculated.
[0032]
In the comparison means 26, the converted value of the primary energy input from the calculating means 25 is memorize | stored, the conversion value and the conversion value input next are compared, and the smaller conversion value and the cogeneration apparatus 1 at that time are compared. The combination of the operating state and the stopped state is newly stored, and after comparing all the combinations, the combination having the smallest converted primary energy value is output as the optimum operating state.
[0033]
In the operation control means 27, in response to the combination of the optimum operation states from the comparison means 26, a drive signal is output to the cogeneration apparatus 1, the switch circuit 20 and the gas boiler 21, and the converted value of primary energy is minimized. The cogeneration system is operated.
[0034]
Next, the conditional expression will be described.
In the first embodiment, the combined heat and power apparatus 1 is operated with the rated power generation amount (100% load) having the highest power generation efficiency, and the electric heater 8 supplies the surplus power whose power demand e (t ′) is smaller than the rated power generation amount. It shall be converted to heat. Here, 1 kW is exemplified as the rated power generation amount. This rated power generation amount is determined by the combined heat and power supply device 1 to be used, for example, 0.8 kW.
[0035]
First, the set time interval d is set to 30 minutes (0.5 hours), and the cogeneration apparatus 1 is operated for 30 minutes (from 0:00 am to 0:30 am) in the first section in one cycle T. Each of the stopped states will be considered with reference to the reference diagram for explaining the operation in FIG. FIG. 5 is not related to the above-described FIG. 3 and FIG. 4 and is illustrated for reference for explanation.
[0036]
▲ 1 ▼ Operating state
As shown in the graph showing the correlation between the power demand and the amount of power generation in (a) of FIG. 5 and the graph showing the correlation between the heat demand and the amount of generated heat in (b) of FIG. The amount of heat converted to heat by the heater 8 is H₁Then, the amount of heat HT to be acquired₁Is
HT₁= H₁+ Generated heat amount CH + Heat amount BH supplemented by the gas boiler 21
And conversion heat amount H₁Is expressed as follows.
[Formula 59]

However, if e (t ′) <F, E₁ (T ′) = e (t ′)
If e (t ′) ≧ F, E₁(T ′) = F
Where E₁(T ′) is the rated power amount when the load power exceeds the power F (1 kW) of the rated power generation amount, and is the power amount that becomes the load power amount when the load power is smaller than the rated power, and e (t ') Is a function indicating a change with time in power demand (load power) specified in advance.
[0037]
Further, the amount of generated heat CH = 0.5 · F · k (35)
It is. Here, k is a thermoelectric ratio.
The amount of heat BH supplemented by the gas boiler 21 is
[Expression 60]

It becomes. BO (t ′) represents a function when the gas boiler 21 is activated so as to compensate for the shortage when the heat amount is insufficient. In FIG. 5B, it is zero.
[0038]
On the other hand, the amount of heat consumed is the amount of heat demand plus the amount of heat released.
[Equation 61]

It becomes. Here, h (t ′) is a function indicating a temporal change in heat demand specified in advance, and ex (t ′) is an amount of heat released from the system.
[0039]
From these things, the amount of heat storage S (0.5) after 30 minutes in the first section,
[62]

It becomes. Here, S (0) is the initial heat storage amount at the start of operation in the first section. Further, the heat storage amount S (0.5) is 0 or more and the maximum heat storage amount S of the heat storage tank 2._maxIt is necessary to satisfy the following conditional expression.
[Equation 63]

That is, here, if the amount of heat is insufficient, the gas boiler 21 is activated to compensate for the insufficient amount of heat.
[0040]
The converted value PE of primary energy here is
PE = GI₁・ Α + BI₁・ Α ’+ BE₁・ Β …… (40)
It becomes. GI₁Is a fuel supply amount required for the operation of the combined heat and power supply apparatus 1 and is expressed by the following equation (41), and α is a converted value to the primary energy of the fuel. Also, BI₁Is a fuel supply amount required for the operation of the gas boiler 21, and α 'is a converted value of the fuel into primary energy. If the fuel of the cogeneration apparatus 1 and the gas boiler 21 are the same, α = α ′.
[Expression 64]

Here, GI (t ′) is a fuel supply amount specified by the combined heat and power supply device 1 to be used.
[0041]
BE₁Is the input amount of the insufficient power within one section time (0.5 hours), and is expressed by the following equation (42), and β is a converted value of the power into primary energy. However, since there is no power shortage here, BE₁Is zero.
[Equation 65]

Here, GP is the power generation amount of the combined heat and power unit 1 within one section time (0.5 hours), and is expressed by the following equation (43).
[Equation 66]

Here, E (t ′) is the rated power amount when the load power exceeds the rated power generation amount, and is the power amount that becomes the load power amount when the load power is smaller than the rated power. That is, when the load power is smaller than the rated power, it becomes zero because there is no power shortage.
[0042]
(2) Stopped operation
As shown in the graph showing the correlation between the power demand and the power generation amount in FIG. 5C and the graph showing the correlation between the heat demand and the generated heat amount in FIG. 5D, the combined heat and power supply apparatus 1 is operated. Therefore, both the amount of heat converted by the electric heater 8 and the amount of generated heat are zero. Accordingly, the heat storage amount S (0.5) after 30 minutes in the first section is obtained by subtracting the heat demand amount and the heat radiation amount from the initial heat storage amount S (0). Only when the amount of heat is insufficient, as shown by the alternate long and short dash line in FIG.₁But,
HT₁= The amount of heat BH supplemented by the gas boiler 21
It becomes. The amount of heat BH to be supplemented by the gas boiler 21 is as in the above equation (36). The conditional expression is the expression (39) as in the above operating state.
[0043]
In this case, the converted value PE of the primary energy is GI.₁・ Α becomes zero,
PE = BI₁・ Α ’+ BE₁・ Β …… (44)
It becomes.
BI₁Is a fuel supply amount required for the operation of the gas boiler 21, and α 'is a converted value of the fuel into primary energy.
BE₁Is the input amount of the shortage of power within one section time (0.5 hours), and is expressed by the following equation (45) because the power generation amount of the cogeneration apparatus 1 is zero, and β Is the converted value of primary power.
[Expression 67]

[0044]
As described above, the operation state and the operation stop state are sequentially obtained in each section every 30 minutes, and the conditional expression is expressed by the following equation (46).
[Equation 68]

Here, n is a positive integer of 1 to 48 (24 ÷ 0.5).
[0045]
The converted value PE of primary energy is as follows.
PE = ΣPE_n= ΣGI_n・ Α + ΣBI_n・ Α ’＋ ΣBE_n・ Β …… (47)
Where ΣPE_nIs the sum of the primary energies of n = 1 to 48. GI_nIs a fuel supply amount required for the operation of the combined heat and power supply device, and is expressed by the following equation (48), and α is a converted value to the primary energy of the fuel, and ΣGI_nΑ is the sum of n = 1 to 48. Also, BI_nIs a fuel supply amount required for operation of the gas boiler 21, α ′ is a converted value of the fuel into primary energy, and ΣBI_nΑ ′ is the sum of n = 1 to 48.
[Equation 69]

Here, GI (t ′) is the fuel supply amount specified by the combined heat and power supply device to be used, and becomes zero in the operation stop state.
[0046]
ΣBE_nIs an input amount of insufficient power within a predetermined time T, which is one cycle T, and is expressed by the following equation (49), and β is a converted value of power to primary energy, and ΣBE_nΒ calculates the sum of n = 1 to 48.
[Equation 70]

Here, GP is the power generation amount of the combined heat and power supply device, and is represented by the following equation (50).
[Equation 71]

Here, E (t ′) is the rated power amount when the load power exceeds the rated power generation amount, and is the power amount that becomes the load power amount when the load power is smaller than the rated power.
[0047]
After the passage of one day as one cycle, the heat acquired in that cycle is allowed to be consumed the next day, and the fluctuation value S (t + n · d) of the heat storage amount in the heat storage tank 2 is the maximum heat storage amount. S_maxAny value within the range not exceeding.
[0048]
As a result of the above, various combinations of the operation stop state and the operation state as described below are input to obtain the converted primary value PE of the primary energy.
(1) The operation is stopped and repeated alternately every 30 minutes. [(A) of FIG. 6]
(2) 0:00 am to 9:00 am, 12:00 am to 5:00 pm (12 to 17:00), and 10 pm to 12:00 pm (22:00 to 24:00). -12:00 am and 5:00 pm to 10:00 pm (17:00 to 22:00) are operated while driving. [(B) of FIG. 6]
(3) 0:00 am to 6:00 am, 3:00 pm to 6:00 pm (15 to 18:00), and 8 pm to 12:00 pm (20 to 24:00) -3pm (6 to 15:00) and 6:00 pm to 8:00 pm (18:00 to 20:00), respectively, are operated. [(C) in FIG. 6]
(3) The operation is stopped from 2:00 am to 6:00 pm (2 to 18:00), and from 0:00 am to 2:00 am and from 6:00 pm to 12:00 pm (18:00 to 24:00). Drive. [(D) of FIG. 6]
[0049]
Finally 2⁴⁸The primary energy conversion value PE is input to the comparison means 26 and sequentially compared, and the smaller primary energy conversion value PE is left, and the operation state and the operation stop state where the primary energy conversion value PE is minimized. The optimum operating state of the combination is obtained, for example, a graph showing the correlation between the power demand and the amount of power generation in FIG. 7A, and a graph showing the correlation between the heat demand and the generated heat amount in FIG. 7B. As shown in the figure, the operation control means 27 performs the operation in the optimum operation state, and the cogeneration system can be operated in the optimum state for improving the energy saving property. In FIG. 7, a indicates the start of operation and b indicates the end of operation.
[0050]
In the first embodiment, one cycle is divided into 30 minutes (0.5 hours) as one day (24 hours). However, in the present invention, for example, one day is 10 minutes or 20 minutes. The period and the divided time interval can be set as appropriate, such as dividing by 3 or by setting a production line or the like to make 3 days or 1 week into one period.
[0051]
Therefore, if one period is T and the division time interval is d, it is as follows.
The optimum operating state of the combination in which the fluctuation value S (t + n · d) of the heat storage amount in the heat storage tank 2 always satisfies the following conditional expression (1), and the converted value PE [Expression (4)] of the following primary energy is minimized. And operating the combined heat and power unit with the rated power generation amount and converting the surplus power when the power demand is smaller than the rated power generation amount into heat with an electrothermal conversion means such as an electric heater according to the determined optimum operating state. It will be.
[Equation 72]

Here, S [t + (n−1) d] indicates the amount of heat stored in the heat storage tank at the start of operation for each divided time. In addition, n is a positive integer of 1 to T / d, h (t ′) is a function indicating a temporal change in heat demand specified in advance, and ex (t ′) is a release from the system. The amount of heat. S_maxIndicates the maximum amount of heat stored in the heat storage tank.
[0052]
HT_nIndicates the amount of heat obtained within the divided time interval d, and is expressed by the following equation (2).
[Equation 73]

Here, F indicates the power of the rated power generation amount, and k indicates the thermoelectric ratio. H_nIs the amount of heat converted from surplus power to heat by the electrothermal conversion means, F> E_nThe amount of (t ′) is integrated and is expressed by the following equation (3).
[Equation 74]

However, if e (t ′) <F, E_n(T ′) = e (t ′)
If e (t ′) ≧ F, E_n(T ′) = F
Where E_n(T ′) is the rated power amount when the load power exceeds the rated power generation amount, and is the power amount that becomes the load power amount when the load power is smaller than the rated power, and e (t ′) is It is a function which shows a time-dependent change of the electric power demand (load electric power) specified beforehand.
In the above equation (2), BO (t ′) represents a function in the case where the auxiliary heating means is activated so as to compensate for the shortage when the shortage of heat occurs.
[0053]
PE = ΣPE_n= ΣGI_n・ Α + ΣBI_n・ Α ’＋ ΣBE_n・ Β …… (4)
Where ΣPE_nIs the sum of the primary energies of n = 1 to T / d. GI_nIs a fuel supply amount required for the operation of the combined heat and power supply device, and is expressed by the following equation (5), and α is a converted value to the primary energy of the fuel, and ΣGI_nΑ is the sum of n = 1 to T / d. Also, BI_nIs the fuel supply amount required for the operation of the auxiliary heating means, α ′ is the converted value of the fuel into the primary energy, and ΣBI_nΑ ′ is the sum of n = 1 to T / d.
[Expression 75]

Here, GI (t ′) is the fuel supply amount specified by the combined heat and power supply device to be used, and becomes zero in the operation stop state.
[0054]
ΣBE_nIs an input amount of insufficient power within a predetermined time T that is one cycle T, and is expressed by the following equation (6), and β is a converted value of the power to primary energy, and n = 1 The total of ~ T / d is obtained.
[76]

Here, GP is the power generation amount of the combined heat and power supply device, and is expressed by the following equation (7).
[77]

Here, E (t ′) is the rated power amount when the load power exceeds the rated power generation amount, and is the power amount that becomes the load power amount when the load power is smaller than the rated power.
[0055]
Next, a second embodiment will be described.
In the second embodiment, when the power demand e (t ′) is smaller than the rated power generation amount 1 kw, power is generated in accordance with the power demand e (t ′), and when the power demand e (t ′) is larger than the rated power generation amount 1 kw, the rated power generation is performed. The combined heat and power supply device 1 is operated so as to generate electricity at an amount of 1 kw.
[0056]
Further, in the second embodiment, the electric heater as in the first embodiment is not used, and the configuration is such that the electric heater 8 and the switch circuit 20 in FIGS. 1 and 2 are eliminated. .
[0057]
▲ 1 ▼ Operating state
Where the power demand e (t ′) is smaller than the rated power generation amount 1 kw, as shown in the graph showing the correlation between the power demand and the power generation amount in FIG. To generate electricity. As shown in the graph showing the correlation between the heat demand and the amount of generated heat in FIG.₁Is
HT₁= Generated heat CH + Heat quantity BH supplemented by the gas boiler 21
Thus, the generated heat amount CH is expressed as follows.
[Formula 78]

Where E₁(T ′) is the amount of power that becomes the rated power amount when the load power exceeds the power of the rated power generation amount, and the amount of power that becomes the load power amount when the load power is smaller than the rated power. B [E₁(T ′)] is the electric energy E_nThe amount of heat generated by the combined heat and power device at (t ′) is shown. In the case of (b) in FIG.₁(T ′) = e (t ′).
[0058]
The amount of heat BH supplemented by the gas boiler 21 is
[79]

It becomes. BO (t ′) represents a function when the gas boiler 21 is activated so as to compensate for the shortage when the heat amount is insufficient. In FIG. 8B, it is zero.
[0059]
On the other hand, the amount of heat consumed is the amount of heat demand plus the amount of heat released.
[80]

It becomes. Here, h (t ′) is a function indicating a temporal change in heat demand specified in advance, and ex (t ′) is an amount of heat released from the system.
[0060]
From these things, the amount of heat storage S (0.5) after 30 minutes in the first section,
[Formula 81]

It becomes. Here, S (0) is the initial heat storage amount at the start of operation in the first section. Further, the heat storage amount S (0.5) is 0 or more and the maximum heat storage amount S of the heat storage tank 2._maxIt is necessary to satisfy the following conditional expression.
[Formula 82]

That is, here, if the amount of heat is insufficient, the gas boiler 21 is activated to compensate for the insufficient amount of heat.
[0061]
The converted value PE of primary energy here is
PE = GI₁・ Α + BI₁・ Α ’+ BE₁・ Β …… (56)
It becomes. GI₁Is a fuel supply amount required for the operation of the combined heat and power supply apparatus 1 and is expressed by the following equation (57), and α is a conversion value to the primary energy of the fuel. Also, BI₁Is a fuel supply amount required for the operation of the gas boiler 21, and α 'is a converted value of the fuel into primary energy. If the fuel of the cogeneration apparatus 1 and the gas boiler 21 are the same, α = α ′.
[Formula 83]

Here, GI (t ′) is a fuel supply amount specified by the combined heat and power supply device 1 to be used.
[0062]
BE₁Is an input amount of insufficient power within one section time (0.5 hours), and is expressed by the following equation (58), and β is a converted value of power into primary energy. However, it is zero here.
[Expression 84]

Here, GP is the power generation amount of the combined heat and power unit 1 within one section time (0.5 hours), and is expressed by the following equation (59).
[Expression 85]

Here, E (t ′) is the rated power amount when the load power exceeds the rated power generation amount, and is the power amount that becomes the load power amount when the load power is smaller than the rated power. That is, when the load power is smaller than the rated power, it becomes zero because there is no power shortage.
[0063]
Where the rated power generation amount is larger than 1 kw, power is generated with the rated power generation amount F as shown in the graph of FIG. 8C showing the correlation between the power demand and the power generation amount. As shown in the graph of FIG. 8D showing the correlation between the heat demand and the amount of generated heat, the amount of heat HT to be acquired_nIs
HT_n= Generated heat CH + Heat quantity BH supplemented by the gas boiler 21
Thus, the generated heat amount CH is expressed as follows.
CH = 0.5 · F · k (60)
Here, k is a thermoelectric ratio.
[0064]
The amount of heat BH supplemented by the gas boiler 21 is
[86]

It becomes. BO (t ′) represents a function when the gas boiler 21 is activated so as to compensate for the shortage when the heat amount is insufficient. In FIG. 8D, it is zero.
[0065]
On the other hand, the amount of heat consumed is the amount of heat demand plus the amount of heat released.
[Expression 87]

It becomes. Here, h (t ′) is a function indicating a temporal change in heat demand specified in advance, and ex (t ′) is an amount of heat released from the system.
[0066]
From these facts, the heat storage amount S (0.5n) after 30 minutes in the n-th section is
[Equation 88]

It becomes. Here, S [0.5 (n-1)] is an initial heat storage amount at the start of operation in the (n-1) section. Further, the heat storage amount S (0.5 n) is 0 or more and the maximum heat storage amount S of the heat storage tank 2._maxIt is necessary to satisfy the following conditional expression.
[Expression 89]

That is, here, if the amount of heat is insufficient, the gas boiler 21 is activated to compensate for the insufficient amount of heat.
[0067]
The converted value PE of primary energy here is
PE = GI_n・ Α + BI_n・ Α ’+ BE_n・ Β …… (65)
It becomes. GI_nIs a fuel supply amount required for the operation of the combined heat and power supply apparatus 1 and is expressed by the following equation (66), and α is a converted value to the primary energy of the fuel. Also, BI_nIs a fuel supply amount required for the operation of the gas boiler 21, and α 'is a converted value of the fuel into primary energy. If the fuel of the cogeneration apparatus 1 and the gas boiler 21 are the same, α = α ′.
[90]

Here, GI (t ′) is a fuel supply amount specified by the combined heat and power supply device 1 to be used.
[0068]
BE_nIs the input amount of the shortage of electric power within one section time (0.5 hours), and is expressed by the following equation (67), and β is a converted value of electric power into primary energy.
[91]

Here, GP is the power generation amount of the combined heat and power unit 1 within one section time (0.5 hours), and is expressed by the following equation (68).
[Equation 92]

Here, E (t ′) is the rated power amount when the load power exceeds the rated power generation amount, and is the power amount that becomes the load power amount when the load power is smaller than the rated power. That is, when the load power is smaller than the rated power, it becomes zero because there is no power shortage.
[0069]
(2) Stopped operation
Since the amount of heat to be converted by the electric heater 8 in the first embodiment is zero, it is the same as the case where the electric heater 8 is not provided, and the operation of this second embodiment is also shown in (c) and (d) of FIG. This is the same as the operation stop state in the first embodiment described above, and the description is omitted.
[0070]
According to this second embodiment, finally 2⁴⁸The primary energy conversion value PE is input to the comparison means 26 and sequentially compared, and the smaller primary energy conversion value PE is left, and the operation state and the operation stop state where the primary energy conversion value PE is minimized. The optimum operating state of the combination is obtained, for example, a graph showing the correlation between the power demand and the amount of power generation in FIG. 9A, and a graph showing the correlation between the heat demand and the generated heat amount in FIG. 9B. As shown in FIG. 5, the operation control means 27 performs the operation in the optimum operation state, and the cogeneration system can be operated in the optimum state for improving the energy saving property. In FIG. 9, “a” indicates the start of operation, and “b” indicates the end of operation.
[0071]
From the above, if one cycle is arranged as T and the division time interval is set as d, the result is as follows.
The optimum operation state of the combination in which the fluctuation value S (t + n · d) of the heat storage amount in the heat storage tank 2 always satisfies the following conditional expression (8) and the following primary energy conversion value PE [Expression (10)] is minimized. The combined heat and power supply device is operated at the rated power generation amount according to the determined optimum operation state, and when the power demand is smaller than the power of the rated power generation amount, it is operated following the change in the power demand.
[Equation 93]

Here, S [t + (n−1) d] indicates the amount of heat stored in the heat storage tank at the start of operation for each divided time. In addition, n is a positive integer of 1 to T / d, h (t ′) is a function indicating a temporal change in heat demand specified in advance, and ex (t ′) is a release from the system. The amount of heat. S_maxIndicates the maximum amount of heat stored in the heat storage tank.
[0072]
HT_nIndicates the amount of heat obtained within the divided time interval d, and is expressed by the following equation (9).
[Equation 94]

Where E_n(T ′) is the amount of power that becomes the rated power amount when the load power exceeds the power of the rated power generation amount, and the amount of power that becomes the load power amount when the load power is smaller than the rated power. B [E_n(T ′)] is the electric energy E_nThe amount of heat generated by the combined heat and power device at (t ′) is shown.
BO (t ′) represents a function in the case where the auxiliary heating means is activated so as to compensate for the shortage when the shortage of heat occurs.
[0073]
PE = ΣPE_n= ΣGI_n・ Α + ΣBI_n・ Α ’＋ ΣBE_n・ Β …… (10)
Where ΣPE_nIs the sum of the primary energies of n = 1 to T / d. GI_nIs a fuel supply amount required for the operation of the combined heat and power supply apparatus, and is expressed by the following equation (5a), and α is a converted value of the fuel to primary energy,_nΑ is the sum of n = 1 to T / d. Also, BI_nIs the fuel supply amount required for the operation of the auxiliary heating means, α ′ is the converted value of the fuel into the primary energy, and ΣBI_nΑ ′ is the sum of n = 1 to T / d.
[95]

Here, GI (t ′) is the fuel supply amount specified by the combined heat and power supply device to be used, and becomes zero in the operation stop state.
[0074]
ΣBE_nIs an input amount of the shortage of power within a predetermined time T that is one cycle T, and is expressed by the following equation (10), and β is a converted value of the power to primary energy, and n = 1 The total of ~ T / d is obtained.
[Equation 96]

Here, GP is a power generation amount of the combined heat and power supply device, and is expressed by the following equation (11).
[Equation 97]

Here, E (t ′) is the rated power amount when the load power exceeds the power of the rated power generation amount, and is the power amount that becomes the load power amount when the load power is smaller than the rated power, and e (t ') Is a function indicating a change with time in power demand (load power) specified in advance.
[0075]
Next, a third embodiment will be described.
In the third embodiment, it is assumed that the thermoelectric generator 1 is operated with the power generation amount set in two stages of 500 w and the rated power generation amount 1 kw. That is, in this third embodiment, the set time interval d is set to 30 minutes (0.5 hours), and the thermoelectric power is generated for 30 minutes (from midnight to 0:30 am) in the first section in one cycle T. The state where the cogeneration apparatus 1 is operated at a rated power generation amount of 1 kW, the state where it is operated at 500 w, and the state where the operation is stopped will be discussed with reference to the operation diagram of FIG.
Moreover, in this 3rd Example, the electric heater 8 as an electrothermal conversion means is provided similarly to 1st Example, and the surplus electric power part for which generated electric power exceeded the electric power demand is converted into heat.
[0076]
(1) Operating condition with rated power generation of 1 kW
As shown in the graph showing the correlation between the power demand and the amount of power generation in FIG. 10A and the graph showing the correlation between the heat demand and the amount of generated heat in FIG. The amount of heat converted to heat by the heater 8 is H₁Then, the amount of heat HT to be acquired₁Is
HT₁= H₁+ Generated heat amount CH + Heat amount BH supplemented by the gas boiler 21
And conversion heat amount H₁Is expressed as follows.
[Equation 98]

However, e (t ′) <F₁If so, E₁ (T ′) = e (t ′)
e (t ′) ≧ F₁If so, E₁(T ′) = F₁
Where E₁(T ′) is the power F at which the load power is the rated power generation amount.₁When (1 kW) is exceeded, it becomes the rated power amount, and when the load power is smaller than the rated power, it is the amount of power that becomes the load power amount, and e (t ′) is the power demand (load power) specified in advance. It is a function showing a change with time.
[0077]
Also, the amount of generated heat CH = 0.5 · F₁・ K₁  ...... (70)
It is. Where k₁Is the rated power generation F₁It is a thermoelectric ratio when driving at (1 kW).
The amount of heat BH supplemented by the gas boiler 21 is
[99]

It becomes. BO (t ′) represents a function when the gas boiler 21 is activated so as to compensate for the shortage when the heat amount is insufficient. In FIG. 10B, it is zero.
[0078]
On the other hand, the amount of heat consumed is the amount of heat demand plus the amount of heat released.
[Expression 100]

It becomes. Here, h (t ′) is a function indicating a temporal change in heat demand specified in advance, and ex (t ′) is an amount of heat released from the system.
[0079]
From these things, the amount of heat storage S (0.5) after 30 minutes in the first section,
## EQU1 ##

It becomes. Here, S (0) is the initial heat storage amount at the start of operation in the first section. Further, the heat storage amount S (0.5) is 0 or more and the maximum heat storage amount S of the heat storage tank 2._maxIt is necessary to satisfy the following conditional expression.
## EQU10 ##

That is, here, if the amount of heat is insufficient, the gas boiler 21 is activated to compensate for the insufficient amount of heat.
[0080]
The converted value PE of primary energy here is
PE = GI₁・ Α + BI₁・ Α ’+ BE₁・ Β …… (75)
It becomes. GI₁Is a fuel supply amount required for the operation of the combined heat and power supply apparatus 1 and is expressed by the following equation (76), and α is a conversion value to the primary energy of the fuel. Also, BI₁Is a fuel supply amount required for the operation of the gas boiler 21, and α 'is a converted value of the fuel into primary energy. If the fuel of the cogeneration apparatus 1 and the gas boiler 21 are the same, α = α ′.
[Formula 103]

Here, GI (t ′) is a fuel supply amount specified by the combined heat and power supply device 1 to be used.
[0081]
BE₁Is an input amount of the shortage of electric power within one section time (0.5 hours), and is expressed by the following equation (77), and β is a converted value of electric power into primary energy. However, it is zero here.
[Formula 104]

Here, GP is the power generation amount of the combined heat and power unit 1 within one section time (0.5 hours), and is expressed by the following equation (78).
[Formula 105]

Where E₁(T ′) is the amount of power that becomes the rated power amount 1 kw when the load power exceeds the power of the rated power generation amount 1 kw, and the load power amount when the load power is smaller than the power of the rated power generation amount 1 kw. That is, when the load power is smaller than the rated power, it becomes zero because there is no power shortage.
[0082]
(2) Operating state with 500w of power generation
As shown in the graph showing the correlation between the power demand and the amount of power generation in (c) of FIG. 10 and the graph showing the correlation between the heat demand and the amount of generated heat in (d) of FIG.₂Is smaller than the electric power demand e (t ′) and there is no surplus electric power.₁Is zero and the amount of heat HT to acquire₁Is
HT₁= Generated heat CH + Heat quantity BH supplemented by the gas boiler 21
It becomes.
[0083]
Also, the amount of generated heat CH = 0.5 · F₂・ K₂  ...... (79)
It is. Where k₂Is the power generation F₂It is a thermoelectric ratio when driving at (500 kW).
The amount of heat BH supplemented by the gas boiler 21 is
[Formula 106]

It becomes. BO (t ′) represents a function when the gas boiler 21 is activated so as to compensate for the shortage when the heat amount is insufficient. In FIG. 10D, it is zero.
[0084]
On the other hand, the amount of heat consumed is the amount of heat demand plus the amount of heat released.
[Expression 107]

It becomes. Here, h (t ′) is a function indicating a temporal change in heat demand specified in advance, and ex (t ′) is an amount of heat released from the system.
[0085]
From these things, the amount of heat storage S (0.5) after 30 minutes in the first section,
[Formula 108]

It becomes. Here, S (0) is the initial heat storage amount at the start of operation in the first section. Further, the heat storage amount S (0.5) is 0 or more and the maximum heat storage amount S of the heat storage tank 2._maxIt is necessary to satisfy the following conditional expression.
[Formula 109]

That is, here, if the amount of heat is insufficient, the gas boiler 21 is activated to compensate for the insufficient amount of heat.
[0086]
The converted value PE of primary energy here is
PE = GI₁・ Α + BI₁・ Α ’+ BE₁・ Β …… (84)
It becomes. GI₁Is a fuel supply amount required for the operation of the combined heat and power supply apparatus 1 and is expressed by the following equation (85), and α is a converted value to the primary energy of the fuel. Also, BI₁Is a fuel supply amount required for the operation of the gas boiler 21, and α 'is a converted value of the fuel into primary energy. If the fuel of the cogeneration apparatus 1 and the gas boiler 21 are the same, α = α ′.
## EQU1 ##

Here, GI (t ′) is a fuel supply amount specified by the combined heat and power supply device 1 to be used.
[0087]
BE₁Is an input amount of the shortage of electric power within one section time (0.5 hours), and is expressed by the following equation (86), and β is a converted value of electric power into primary energy.
[Formula 111]

Here, GP is the power generation amount of the combined heat and power unit 1 within one section time (0.5 hours), and is expressed by the following equation (87).
## EQU1 ##

Where E₁(T ′) is the set power amount 500w when the load power exceeds the set power generation amount 500w, and the load power amount when the load power is smaller than the set power generation amount 500w.
[0088]
(3) Stopped operation
The operation of the third embodiment is the same as the operation stop state in the first embodiment described with reference to (c) and (d) of FIG.
[0089]
In the case of this third embodiment, finally 3⁴⁸The primary energy conversion value PE is input to the comparison means 26, and the power generation amounts 500w and 1kw are respectively reduced such that the smaller one of the primary energy conversion values PE is left as a result of comparison and the primary energy conversion value PE is minimized. The optimum operation state of the combination of the operation state and the operation stop state is obtained. For example, the graph showing the correlation between the power demand and the amount of power generation in FIG. 11A and the heat demand in FIG. As shown in the graph showing the correlation with the amount of generated heat, the operation control means 27 performs the operation in the optimum operation state, and the cogeneration system can be operated in the optimum state for improving the energy saving property. In FIG. 11, a1 indicates the start of operation with a power generation amount 500w, a2 indicates the end of the operation with power generation amount 500w and when the operation starts with a power generation amount 1kw, and a3 indicates the end of operation with a power generation amount 1kw. .
[0090]
After the passage of one day as one cycle, the heat acquired in that cycle is allowed to be consumed the next day, and the fluctuation value S (t + n · d) of the heat storage amount in the heat storage tank 2 is the maximum heat storage amount. S_maxAny value within the range not exceeding.
Further, in the third embodiment, two types of step operation, 500 w operation and rated power generation 1 kw operation, are performed. In the present invention, for example, two steps of 700 w operation and rated power generation 1 kw operation are performed. Operation with the set power generation amount may be performed, or operation with the power generation amount set to three or more stages such as 500 w operation, 700 w operation, and rated power generation 1 kw operation may be performed. It includes the case of doing.
[0091]
From the above, if one cycle is arranged as T and the division time interval is set as d, the result is as follows.
The optimum operation state of the combination in which the fluctuation value S (t + n · d) of the heat storage amount in the heat storage tank 2 always satisfies the following conditional expression (13) and the converted value PE [Expression (16)] of the following primary energy is minimized. In accordance with the determined optimum operating state, the combined heat and power supply apparatus 1 is operated with a set power generation amount of a plurality of stages, and surplus power when the power demand is smaller than the power of the set power generation amount is converted by an electrothermal conversion means such as an electric heater. It will be converted to heat.
[Formula 113]

Here, S [t + (n−1) d] indicates the amount of heat stored in the heat storage tank at the start of operation for each divided time. In addition, n is a positive integer of 1 to T / d, h (t ′) is a function indicating a temporal change in heat demand specified in advance, and ex (t ′) is a release from the system. The amount of heat. S_maxIndicates the maximum amount of heat stored in the heat storage tank.
[0092]
HT_nIndicates the amount of heat obtained within the divided time interval d, and is expressed by the following equation (14).
[Formula 114]

Where F_mIs the set power generation amount, k_mIs the set power generation amount F_mThe thermoelectric ratios at are shown respectively. m is a positive integer greater than or equal to 2 and up to the set number of power generation levels. H_nIs the amount of heat converted from surplus power to heat by the electrothermal conversion means, F_m> E_nThe amount of (t ′) is integrated and is expressed by the following equation (15).
[Expression 115]

However, e (t ′) <F_mIf so, E_n(T ′) = e (t ′)
e (t ′) ≧ F_mIf so, E_n(T ′) = F_m
Where E_n(T '), the load power is the set power generation amount F_mExceeds the set power amount, and the load power is the set power generation amount F._mWhen it is smaller, it is the amount of power that becomes the load power amount, and e (t ′) is a function that indicates a change in power demand (load power) specified in advance over time.
In the above equation (14), BO (t ′) represents a function in the case where the auxiliary heating means is activated so as to compensate for the shortage when the shortage of heat occurs.
[0093]
PE = ΣPE_n= ΣGI_n・ Α + ΣBI_n・ Α ’＋ ΣBE_n・ Β …… (16)
Where ΣPE_nIs the sum of the primary energies of n = 1 to T / d. GI_nIs a fuel supply amount required for the operation of the combined heat and power supply device, and is expressed by the following equation (17), and α is a converted value to the primary energy of the fuel, and ΣGI_nΑ is the sum of n = 1 to T / d. Also, BI_nIs the fuel supply amount required for the operation of the auxiliary heating means, α ′ is the converted value of the fuel into the primary energy, and ΣBI_nΑ ′ is the sum of n = 1 to T / d.
[Formula 116]

Here, GI (t ′) is the fuel supply amount specified by the combined heat and power supply device to be used, and becomes zero in the operation stop state.
[0094]
ΣBE_nIs an input amount of insufficient power within a predetermined time T that is one cycle T, and is expressed by the following equation (18), and β is a converted value of the power to primary energy, and n = 1 The total of ~ T / d is obtained.
[Expression 117]

Here, GP is a power generation amount of the combined heat and power supply device, and is represented by the following equation (19).
[Formula 118]

Here, E (t ′) indicates that the load power is the set power generation amount F._mExceeds the set power amount, and the load power is the set power generation amount F._mIf it is smaller, it is the amount of power that becomes the load power amount.
[0095]
FIG. 12 is a system configuration diagram showing a fourth embodiment of the cogeneration system. The differences from the first embodiment are as follows.
That is, the electric heater 8 is eliminated, the power supply line 32 is connected to the power line 15 via the switch circuit 31, and the power selling means 33 is configured to sell the surplus power to a third party when surplus power is generated. Has been.
A wattmeter 34 is interposed in the power supply line 32 and is configured to measure the amount of power sold to a third party. Other configurations are the same as those of the first embodiment, and the description thereof is omitted by assigning the same reference numerals.
[0096]
As shown in the block diagram of the fourth embodiment of FIG. 13, a microcomputer 35 is connected to the combined heat and power supply device 1, the switch circuit 31, and the gas boiler 21.
As in the first embodiment, the microcomputer 35 includes a demand change specifying unit 23, an operation state input unit 24, a calculation unit 25, a comparison unit 26, and an operation control unit 27.
[0097]
In the fourth embodiment, the amount of acquired heat is reduced by the amount not converted into heat by the electric heater 8, and the converted value of primary energy is reduced by the amount of surplus power sold to the third party converted to primary energy. This will be explained next.
[0098]
▲ 1 ▼ Operating state
The amount of heat HT to acquire₁Is
HT₁= Generated heat CH + Heat quantity BH supplemented by the gas boiler 21
It becomes.
[0099]
Also, the amount of generated heat CH = 0.5 · F · k (88)
It is. Here, k is a thermoelectric ratio.
The amount of heat BH supplemented by the gas boiler 21 is
[Formula 119]

It becomes. BO (t ′) represents a function when the gas boiler 21 is activated so as to compensate for the shortage when the heat amount is insufficient.
[0100]
On the other hand, the amount of heat consumed is the amount of heat demand plus the amount of heat released.
[Expression 120]

It becomes. Here, h (t ′) is a function indicating a temporal change in heat demand specified in advance, and ex (t ′) is an amount of heat released from the system.
[0101]
From these things, the amount of heat storage S (0.5) after 30 minutes in the first section,
[Equation 121]

It becomes. Here, S (0) is the initial heat storage amount at the start of operation in the first section. Further, the heat storage amount S (0.5) is 0 or more and the maximum heat storage amount S of the heat storage tank 2._maxIt is necessary to satisfy the following conditional expression.
[Equation 122]

That is, here, if the amount of heat is insufficient, the gas boiler 21 is activated to compensate for the insufficient amount of heat.
[0102]
The converted value PE of primary energy here is
PE = GI₁・ Α + BI₁・ Α ’+ BE₁・ Β-SE₁・ Γ …… (93)
It becomes. GI₁Is a fuel supply amount required for the operation of the combined heat and power supply device 1 and is expressed by the following equation (94), and α is a converted value to the primary energy of the fuel. Also, BI₁Is a fuel supply amount required for the operation of the gas boiler 21, and α 'is a converted value of the fuel into primary energy. If the fuel of the cogeneration apparatus 1 and the gas boiler 21 are the same, α = α ′.
[Formula 123]

Here, GI (t ′) is a fuel supply amount specified by the combined heat and power supply device 1 to be used.
[0103]
BE₁Is an input amount of the shortage of electric power within one section time (0.5 hours), and is expressed by the following equation (95), and β is a converted value of electric power into primary energy. However, since there is no power shortage here, BE₁Is zero.
[Expression 124]

Here, GP is the power generation amount of the combined heat and power unit 1 within one section time (0.5 hours), and is expressed by the following equation (96).
[Expression 125]

Here, E (t ′) is the rated power amount when the load power exceeds the rated power generation amount, and is the power amount that becomes the load power amount when the load power is smaller than the rated power. That is, when the load power is smaller than the rated power, it becomes zero because there is no power shortage.
[0104]
SE₁Is the surplus power amount sold to the third party by the power selling means (corresponding to the surplus power YE in FIG. 5A), and F> E₁The amount of (t ′) is integrated and is expressed by the following equation (97), and γ is a converted value obtained by converting the price when selling to a third party into primary energy.
[Expression 126]

However, if e (t ′) <F, E₁(T ′) = e (t ′)
If e (t ′) ≧ F, E₁(T ′) = F
Where E₁(T ′) is the rated power amount when the load power exceeds the rated power generation amount, and is the power amount that becomes the load power amount when the load power is smaller than the rated power, and e (t ′) is It is a function which shows a time-dependent change of the electric power demand (load electric power) specified beforehand.
[0105]
(2) Stopped operation
Since the cogeneration apparatus 1 is not operated, no surplus power is generated, which is the same as the case described in the first embodiment. That is, acquired heat quantity HT₁But,
HT₁= The amount of heat BH supplemented by the gas boiler 21
Thus, the amount of heat BH supplemented by the gas boiler 21 is as described in the above equation (89). The conditional expression is the expression (92) as in the operation state described above.
[0106]
In this case, the converted value PE of the primary energy is GI.₁・ Α and SE₁・ Γ becomes zero,
PE = BI₁・ Α ’+ BE₁・ Β …… (98)
It becomes.
BI₁Is a fuel supply amount required for the operation of the gas boiler 21, and α 'is a converted value of the fuel into primary energy.
BE₁Is the input amount of power shortage within one section time (0.5 hours), and is expressed by the following equation (99) because the power generation amount of the combined heat and power supply device 1 is zero, and β Is the converted value of primary power.
[Expression 127]

[0107]
As described above, the operation state and the operation stop state are sequentially obtained in each section every 30 minutes, and the conditional expression is expressed by the following expression (100).
[Expression 128]

Here, n is a positive integer of 1 to 48 (24 ÷ 0.5).
[0108]
The converted value PE of primary energy is as follows.

Where ΣPE_nIs the sum of the primary energies of n = 1 to 48. GI_nIs a fuel supply amount required for the operation of the combined heat and power device, and is expressed by the following equation (102), and α is a converted value of the fuel to primary energy, and ΣGI_nΑ is the sum of n = 1 to 48. Also, BI_nIs a fuel supply amount required for operation of the gas boiler 21, α ′ is a converted value of the fuel into primary energy, and ΣBI_nΑ ′ is the sum of n = 1 to 48.
[Expression 129]

Here, GI (t ′) is the fuel supply amount specified by the combined heat and power supply device to be used, and becomes zero in the operation stop state.
[0109]
ΣBE_nIs an input amount of insufficient power within a predetermined time T, which is one cycle T, and is expressed by the following equation (103), and β is a converted value of power to primary energy, and ΣBE_nΒ calculates the sum of n = 1 to 48.
[Expression 130]

Here, GP is the power generation amount of the combined heat and power supply device, and is expressed by the following equation (104).
[Equation 131]

Here, E (t ′) is the rated power amount when the load power exceeds the rated power generation amount, and is the power amount that becomes the load power amount when the load power is smaller than the rated power.
[0110]
Also, ΣSE_nIs the amount of surplus power sold to third parties by means of power selling, F> E_n(T ′) is integrated and is expressed by the following equation (105), and γ is a converted value obtained by converting the price when selling to a third party into primary energy, and n = 1 to 48 sums are being sought.
[Expression 132]

However, if e (t ′) <F, E_n(T ′) = e (t ′)
If e (t ′) ≧ F, E_n(T ′) = F
Where E_n(T ′) is the rated power amount when the load power exceeds the rated power generation amount, and is the power amount that becomes the load power amount when the load power is smaller than the rated power, and e (t ′) is It is a function which shows a time-dependent change of the electric power demand (load electric power) specified beforehand.
[0111]
After the passage of one day as one cycle, the heat acquired in that cycle is allowed to be consumed the next day, and the fluctuation value S (t + n · d) of the heat storage amount in the heat storage tank 2 is the maximum heat storage amount. S_maxAny value within the range not exceeding.
[0112]
As a result of the above, as in the first embodiment, various combinations of the operation stop state and the operation state are input to obtain the converted value PE of the primary energy.
[0113]
Finally 2⁴⁸The primary energy conversion value PE is input to the comparison means 26 and sequentially compared, and the smaller primary energy conversion value PE is left, and the operation state and the operation stop state where the primary energy conversion value PE is minimized. The optimum operation state of the combination is obtained, and the operation control means 27 performs the operation in the optimum operation state, so that the cogeneration system can be operated in the optimum state for improving the energy saving property.
[0114]
In the fourth embodiment, when one cycle is T and the division time interval is d, the following is obtained.
The optimum operation state of the combination in which the fluctuation value S (t + n · d) of the heat storage amount in the heat storage tank 2 always satisfies the following conditional expression (20) and the following converted value PE [Expression (22)] of the primary energy is minimized. And the surplus power when the power demand is smaller than the power of the rated power generation amount is sold to the third party by the power selling means 33 according to the determined optimum operation state. Become.
[Formula 133]

Here, S [t + (n−1) d] indicates the amount of heat stored in the heat storage tank at the start of operation for each divided time. In addition, n is a positive integer of 1 to T / d, h (t ′) is a function indicating a temporal change in heat demand specified in advance, and ex (t ′) is a release from the system. The amount of heat. S_maxIndicates the maximum amount of heat stored in the heat storage tank.
HT_nIndicates the amount of heat obtained within the divided time interval d, and is expressed by the following equation (21).
[Formula 134]

Here, F indicates the power of the rated power generation amount, and k indicates the thermoelectric ratio.
In the above equation (21), BO (t ′) represents a function when the auxiliary heating means is activated so as to compensate for the shortage when a shortage of heat occurs.

Where ΣPE_nIs the sum of the primary energies of n = 1 to T / d. GI_nIs a fuel supply amount required for operation of the combined heat and power supply device, and is expressed by the following equation (23), and α is a converted value of the fuel to primary energy, and ΣGI_nΑ is the sum of n = 1 to T / d. Also, BI_nIs the fuel supply amount required for the operation of the auxiliary heating means, α ′ is the converted value of the fuel into the primary energy, and ΣBI_nΑ ′ is the sum of n = 1 to T / d.
[Expression 135]

Here, GI (t ′) is the fuel supply amount specified by the combined heat and power supply device to be used, and becomes zero in the operation stop state.
ΣBE_nIs an input amount of insufficient power within a predetermined time T that is one cycle T, and is expressed by the following equation (24), and β is a converted value of the power into primary energy, and n = 1 The total of ~ T / d is obtained.
[Formula 136]

Here, GP is the power generation amount of the combined heat and power supply device, and is represented by the following equation (25).
[Expression 137]

Here, E (t ′) is the rated power amount when the load power exceeds the rated power generation amount, and is the power amount that becomes the load power amount when the load power is smaller than the rated power. Also, ΣSE_nIs the amount of surplus power sold to third parties by means of power selling, F> E_n(T ′) is integrated and is expressed by the following equation (26), and γ is a converted value obtained by converting the price when selling to a third party into primary energy, and n = 1 to The total sum of T / d is obtained.
[Formula 138]

However, if e (t ′) <F, E_n(T ′) = e (t ′)
If e (t ′) ≧ F, E_n(T ′) = F
Where E_n(T ′) is the rated power amount when the load power exceeds the rated power generation amount, and is the power amount that becomes the load power amount when the load power is smaller than the rated power, and e (t ′) is It is a function which shows a time-dependent change of the electric power demand (load electric power) specified beforehand.
[0115]
Next, a fifth embodiment will be described.
In the fifth embodiment, similarly to the third embodiment, the combined heat and power supply apparatus 1 is operated with a power generation amount set in two stages of 500 w and a rated power generation amount 1 kw. Further, in the fifth embodiment, the power selling means 33 is provided as in the fourth embodiment, and surplus power whose generated power exceeds the power demand is sold to a third party.
[0116]
(1) Operating condition with rated power generation of 1 kW
The amount of heat HT to acquire₁Is
HT₁= H₁+ Generated heat amount CH + Heat amount BH supplemented by the gas boiler 21
It becomes.
[0117]
Also, the amount of generated heat CH = 0.5 · F₁・ K₁  ...... (106)
It is. Where k₁Is the rated power generation F₁It is a thermoelectric ratio when driving at (1 kW).
The amount of heat BH supplemented by the gas boiler 21 is
[Formula 139]

It becomes. BO (t ′) represents a function when the gas boiler 21 is activated so as to compensate for the shortage when the heat amount is insufficient. In FIG. 10B, it is zero.
[0118]
On the other hand, the amount of heat consumed is the amount of heat demand plus the amount of heat released.
[Formula 140]

It becomes. Here, h (t ′) is a function indicating a temporal change in heat demand specified in advance, and ex (t ′) is an amount of heat released from the system.
[0119]
From these things, the amount of heat storage S (0.5) after 30 minutes in the first section,
[Formula 141]

It becomes. Here, S (0) is the initial heat storage amount at the start of operation in the first section. Further, the heat storage amount S (0.5) is 0 or more and the maximum heat storage amount S of the heat storage tank 2._maxIt is necessary to satisfy the following conditional expression.
[Expression 142]

That is, here, if the amount of heat is insufficient, the gas boiler 21 is activated to compensate for the insufficient amount of heat.
[0120]
The converted value PE of primary energy here is
PE = GI₁・ Α + BI₁・ Α ’+ BE₁・ Β-SE₁・ Γ …… (111)
It becomes. GI₁Is a fuel supply amount required for the operation of the combined heat and power supply apparatus 1 and is expressed by the following equation (112), and α is a converted value to the primary energy of the fuel. Also, BI₁Is a fuel supply amount required for the operation of the gas boiler 21, and α 'is a converted value of the fuel into primary energy. If the fuel of the cogeneration apparatus 1 and the gas boiler 21 are the same, α = α ′.
[Expression 143]

Here, GI (t ′) is a fuel supply amount specified by the combined heat and power supply device 1 to be used.
[0121]
BE₁Is an input amount of the shortage of electric power within one section time (0.5 hours), and is expressed by the following equation (113), and β is a converted value of electric power into primary energy.
However, it is zero here.
[Expression 144]

Here, GP is the power generation amount of the combined heat and power unit 1 within one section time (0.5 hours), and is expressed by the following equation (114).
[Expression 145]

Where E₁(T ′) is the amount of power that becomes the rated power amount 1 kw when the load power exceeds the power of the rated power generation amount 1 kw, and the load power amount when the load power is smaller than the power of the rated power generation amount 1 kw. That is, when the load power is smaller than the rated power, it becomes zero because there is no power shortage.
[0122]
SE₁Is the surplus power amount sold to the third party by the power selling means [corresponding to surplus power YE in FIG.₁> E₁The amount of (t ′) is integrated and is expressed by the following equation (115), and γ is a converted value obtained by converting the price when selling to a third party into primary energy.
146

However, e (t ′) <F₁If so, E₁(T ′) = e (t ′)
e (t ′) ≧ F₁If so, E₁(T ′) = F₁
Where E₁(T ′) is the rated power amount when the load power exceeds the rated power generation amount, and is the power amount that becomes the load power amount when the load power is smaller than the rated power, and e (t ′) is It is a function which shows a time-dependent change of the electric power demand (load electric power) specified beforehand.
[0123]
(2) Operating state with 500w of power generation
As shown in the graph showing the correlation between the power demand and the amount of power generation in (c) of FIG. 10 and the graph showing the correlation between the heat demand and the amount of generated heat in (d) of FIG.₂Is smaller than the electric power demand e (t ′) and there is no surplus electric power.₁Is zero and the amount of heat HT to acquire₁Is
HT₁= Generated heat CH + Heat quantity BH supplemented by the gas boiler 21
It becomes.
[0124]
Also, the amount of generated heat CH = 0.5 · F₂・ K₂  ...... (116)
It is. Where k₂Is the power generation F₂It is a thermoelectric ratio when driving at (500 kW).
The amount of heat BH supplemented by the gas boiler 21 is
[Expression 147]

It becomes. BO (t ′) represents a function when the gas boiler 21 is activated so as to compensate for the shortage when the heat amount is insufficient. In FIG. 10D, it is zero.
[0125]
On the other hand, the amount of heat consumed is the amount of heat demand plus the amount of heat released.
[Formula 148]

It becomes. Here, h (t ′) is a function indicating a temporal change in heat demand specified in advance, and ex (t ′) is an amount of heat released from the system.
[0126]
From these things, the amount of heat storage S (0.5) after 30 minutes in the first section,
149

It becomes. Here, S (0) is the initial heat storage amount at the start of operation in the first section. Further, the heat storage amount S (0.5) is 0 or more and the maximum heat storage amount S of the heat storage tank 2._maxIt is necessary to satisfy the following conditional expression.
[Expression 150]

That is, here, if the amount of heat is insufficient, the gas boiler 21 is activated to compensate for the insufficient amount of heat.
[0127]
The converted value PE of primary energy here is
PE = GI₁・ Α + BI₁・ Α ’+ BE₁・ Β …… (121)
It becomes. GI₁Is a fuel supply amount required for the operation of the combined heat and power supply apparatus 1 and is expressed by the following equation (122), and α is a converted value of the fuel into primary energy. Also, BI₁Is a fuel supply amount required for the operation of the gas boiler 21, and α 'is a converted value of the fuel into primary energy. If the fuel of the cogeneration apparatus 1 and the gas boiler 21 are the same, α = α ′.
[Formula 151]

Here, GI (t ′) is a fuel supply amount specified by the combined heat and power supply device 1 to be used.
[0128]
BE₁Is the input amount of the shortage of power within one section time (0.5 hours), and is expressed by the following equation (123), and β is a converted value of the power into primary energy.
[Formula 152]

Here, GP is the power generation amount of the combined heat and power unit 1 within one section time (0.5 hours), and is expressed by the following equation (124).
[Expression 153]

Where E₁(T ′) is the set power amount 500w when the load power exceeds the set power generation amount 500w, and the load power amount when the load power is smaller than the set power generation amount 500w. In addition, when this load electric power is smaller than the electric power of setting power generation amount 500w, surplus electric power generate | occur | produces and the converted value of primary energy is calculated | required by (111) Formula.
[0129]
(3) Stopped operation
The operation of the fifth embodiment is the same as the operation stop state in the first embodiment described with reference to (c) and (d) of FIG.
[0130]
In the case of this fifth embodiment, finally 3⁴⁸The primary energy conversion value PE is input to the comparison means 26 and sequentially compared, and the smaller primary energy conversion value PE is left, and the primary energy conversion value PE is minimized. The optimum operation state of the combination of the operation state and the operation stop state is obtained, the operation control means 27 performs the operation in the optimum operation state, and the cogeneration system can be operated in the optimum state for improving energy saving. .
[0131]
After the passage of one day as one cycle, the heat acquired in that cycle is allowed to be consumed the next day, and the fluctuation value S (t + n · d) of the heat storage amount in the heat storage tank 2 is the maximum heat storage amount. S_maxAny value within the range not exceeding.
Further, in the third embodiment, two types of step operation, 500 w operation and rated power generation 1 kw operation, are performed. In the present invention, for example, two steps of 700 w operation and rated power generation 1 kw operation are performed. Operation with the set power generation amount may be performed, or operation with the power generation amount set to three or more stages such as 500 w operation, 700 w operation, and rated power generation 1 kw operation may be performed. It includes the case of doing.
[0132]
From the above, if one cycle is arranged as T and the division time interval is set as d, the result is as follows.
The optimum operation state of the combination in which the fluctuation value S (t + n · d) of the heat storage amount in the heat storage tank 2 always satisfies the following conditional expression (27) and the following primary energy conversion value PE [Expression (29)] is minimized. The combined heat and power supply apparatus 1 is operated with a set power generation amount in a plurality of stages according to the determined optimum operation state, and surplus power when the power demand is smaller than the power of the set power generation amount is converted by an electrothermal conversion means such as an electric heater. It will be converted to heat.
[Expression 154]

Here, S [t + (n−1) d] indicates the amount of heat stored in the heat storage tank at the start of operation for each divided time. In addition, n is a positive integer of 1 to T / d, h (t ′) is a function indicating a temporal change in heat demand specified in advance, and ex (t ′) is a release from the system. The amount of heat. S_maxIndicates the maximum amount of heat stored in the heat storage tank.
[0133]
HT_nIndicates the amount of heat obtained within the divided time interval d, and is expressed by the following equation (28).
[Expression 155]

Where F_mIs the set power generation amount, k_mIs the set power generation amount F_mThe thermoelectric ratios at are shown respectively. m is a positive integer greater than or equal to 2 and up to the set number of power generation levels.
In the above equation (28), BO (t ′) represents a function when the auxiliary heating means is activated so as to compensate for the shortage when the shortage of heat occurs.

Where ΣPE_nIs the sum of the primary energies of n = 1 to T / d. GI_nIs a fuel supply amount required for the operation of the combined heat and power supply device, and is expressed by the following equation (30), and α is a converted value to the primary energy of the fuel, and ΣGI_nΑ is the sum of n = 1 to T / d. Also, BI_nIs the fuel supply amount required for the operation of the auxiliary heating means, α ′ is the converted value of the fuel into the primary energy, and ΣBI_nΑ ′ is the sum of n = 1 to T / d.
156

Here, GI (t ′) is the fuel supply amount specified by the combined heat and power supply device to be used, and becomes zero in the operation stop state.
ΣBE_nIs an input amount of insufficient power within a predetermined time T that is one cycle T, and is expressed by the following equation (31), and β is a converted value of the power to primary energy, and n = 1 The total of ~ T / d is obtained.
[Expression 157]

Here, GP is the power generation amount of the combined heat and power supply device, and is represented by the following equation (32).
[Formula 158]

Here, E (t ′) is the rated power amount when the load power exceeds the rated power generation amount, and is the power amount that becomes the load power amount when the load power is smaller than the rated power. Also, ΣSE_nIs the amount of surplus power sold to third parties by means of power selling, F> E_n(T ′) is integrated and is expressed by the following equation (33), and γ is a converted value obtained by converting the price when selling to a third party into primary energy, and n = 1 to The total sum of T / d is obtained.
[Expression 159]

However, e (t ′) <F_mIf so, E_n(T ′) = e (t ′)
e (t ′) ≧ F_mIf so, E_n(T ′) = F
Where E_n(T '), the load power is the set power generation amount F_mExceeds the set power amount, and the load power is the set power generation amount F._mWhen it is smaller, it is the amount of power that becomes the load power amount, and e (t ′) is a function that indicates a change in power demand (load power) specified in advance over time.
[0134]
FIG. 14 is a block diagram of the sixth embodiment. The differences from the first embodiment are as follows.
That is, the microcomputer 22 is connected to the start / stop number setting means 41 for setting the number of start / stops in one cycle of the cogeneration apparatus 1, and the start / stop number set by the start / stop number setting means 41 is input to the calculation means 25. It is supposed to be.
[0135]
The calculation means 25 calculates the converted value of primary energy when the number of start / stop times of the operation state input from the operation state input means 24 exceeds the set start / stop number input from the start / stop number setting means 41. It stops and shifts to the input of the next operation state.
[0136]
According to the sixth embodiment, it is possible to obtain the optimum operating state of the combination in which the number of start / stops in one cycle of the combined heat and power supply apparatus 1 is equal to or less than the set number and the converted primary value PE of the primary energy is minimum. 1 durability can be improved.
As the number of start / stop times, a desired number of times may be set as appropriate depending on the characteristics of the combined heat and power supply device 1 and the desired service life. For example, if the desired service life is 10 years, it is set to about 3 times, and considering the replacement of the starter or the like, it is set to about 6 times. This configuration can be similarly applied to the second, third, fourth and fifth embodiments.
[0137]
The heat dissipation amount ex (t ′) from the system in each of the first, second, third, fourth, fifth and sixth embodiments is the amount of heat released from the housing of the heat storage tank 2, the piping and the combined heat and power supply device 1. Including heat quantity ST (t), PL (t), and GE (t), all are determined mainly by the heat capacity proportional to the scale at the time of system construction. For example, if a configuration in which the casing of the pipe and the combined heat and power supply device 1 and the heat storage tank 2 are covered with a heat insulating material is adopted, the heat radiation amount can be suppressed, but the heat insulating effect of the heat insulating material can also be specified in advance when the system is constructed. In any case, the amount of heat released from the piping, the casing of the combined heat and power supply device 1 and the heat storage tank 2 can be specified in advance through experiments, calculations, learning effects, and the like.
[0138]
The initial heat storage amount S (0) is appropriately set based on the power demand and heat demand specified in advance, and can be specified in advance. Based on Table-1, the initial heat storage amount is 2,000 [× (1/860) kW].
[0139]
The present invention can be applied to cogeneration systems for various uses such as home use, manufacturing factories, and commercial buildings.
[0140]
【The invention's effect】
  As is clear from the above description, the claim 1And claim 2According to the operation method of the cogeneration system according to the invention, surplus power exceeding the power demand when the power demand is smaller than the rated power generation amount is converted into heat by the electrothermal conversion means, and the combined heat and power supply device is converted into the rated power generation amount. Since power is generated by operation, the apparent power generation efficiency can be increased as compared with the case of operation with a power generation amount smaller than the rated power generation amount.
  Moreover, for example, it was allowed not to stay within one cycle such as one day, but to be used to cover part of the heat demand within the next one cycle, such as the heat demand for the next morning, and stored in a heat storage tank. To cover the heat demand with the amount of heat that is dissipated before and after the consumption, and to cover the shortage of electricity with electricity purchase means, with the converted heat, the heat generated by the combined heat and power unit, and the amount of heat stored in the heat storage tank In consideration of supplementing the shortage of heat with auxiliary heating means when there is a shortage, the operation is performed so that the total conversion value to primary energy is minimized. Even if a shortage of heat occurs, it can be dealt with satisfactorily by using the auxiliary heating means, and the combined heat and power supply apparatus can be operated by selecting a state with less heat dissipation loss, so that energy saving can be improved satisfactorily.
[0141]
  Claims3 and claim 4According to the operation method of the cogeneration system according to the invention, when the power demand exceeds the rated power generation amount, the combined heat and power generation device is operated with the rated power generation amount to generate power, so that the power generation efficiency can be increased, and the power demand is rated. When it is smaller than the amount of power generation, the combined heat and power unit is operated to follow the power demand to generate power and not generate surplus power. The configuration for doing so can be made unnecessary.
  Moreover, for example, it was allowed not to stay within one cycle such as one day, but to be used to cover part of the heat demand within the next one cycle, such as the heat demand for the next morning, and stored in a heat storage tank. To cover the heat demand with the amount of heat that is dissipated before and after the consumption, and to cover the shortage of electricity with electricity purchase means, with the converted heat, the heat generated by the combined heat and power unit, and the amount of heat stored in the heat storage tank In consideration of supplementing the shortage of heat with auxiliary heating means when there is a shortage, the operation is performed so that the total conversion value to primary energy is minimized. Even if a shortage of heat occurs, it can be dealt with satisfactorily by using the auxiliary heating means, and the combined heat and power supply apparatus can be operated by selecting a state with less heat dissipation loss, so that energy saving can be improved satisfactorily.
[0142]
  Claims5 and claim 6According to the operation method of the cogeneration system of the invention according to the present invention, since the combined heat and power supply device is operated with the power generation amount set in a plurality of stages, it is possible to perform an efficient operation with less surplus power than when always operating at a constant output.
  Moreover, for example, it was allowed not to stay within one cycle such as one day, but to be used to cover part of the heat demand within the next one cycle, such as the heat demand for the next morning, and stored in a heat storage tank. To cover the heat demand with the amount of heat that is dissipated before and after the consumption, and to cover the shortage of electricity with electricity purchase means, with the converted heat, the heat generated by the combined heat and power unit, and the amount of heat stored in the heat storage tank In consideration of supplementing the shortage of heat with auxiliary heating means when there is a shortage, the operation is performed so that the total conversion value to primary energy is minimized. Even if a shortage of heat occurs, it can be dealt with satisfactorily by using the auxiliary heating means, and the combined heat and power supply apparatus can be operated by selecting a state with less heat dissipation loss, so that energy saving can be improved satisfactorily.
[0143]
  Claims7 and claim 8According to the operation method of the cogeneration system according to the invention, surplus power exceeding the power demand when the power demand is smaller than the rated power generation amount is sold to a third party by the power selling means, and the combined heat and power device is connected to the rated power generation amount. Therefore, it is possible to increase the apparent power generation efficiency as compared with the case of operating with a power generation amount smaller than the rated power generation amount.
  Moreover, for example, it was allowed not to stay within one cycle such as one day, but to be used to cover part of the heat demand within the next one cycle, such as the heat demand for the next morning, and stored in a heat storage tank. The amount of heat that is dissipated before the heat is consumed, the shortage of power is covered by power purchase means, the surplus power is sold to a third party by power sale means, and the heat generated in the combined heat and power supply device Operate so that the converted value to primary energy is minimized, taking into account supplementing the insufficient heat with auxiliary heating means when the amount of heat stored in the heat storage tank is insufficient to cover the heat demand. Therefore, even if there is a slight shortage of heat due to the capacity limitation of the heat storage tank, it is possible to cope well with the use of auxiliary heating means, select a state with less heat loss, and operate the combined heat and power unit, saving energy Can be improved satisfactorily.
[0144]
  Claims9 and claim 10According to the operation method of the cogeneration system of the invention according to the present invention, since the combined heat and power supply device is operated with the power generation amount set in a plurality of stages, it is possible to perform an efficient operation with less surplus power than when always operating at a constant output.
  Moreover, for example, it was allowed not to stay within one cycle such as one day, but to be used to cover part of the heat demand within the next one cycle, such as the heat demand for the next morning, and stored in a heat storage tank. The amount of heat that is dissipated before the heat is consumed, the shortage of power is covered by power purchase means, the surplus power is sold to a third party by power sale means, and the heat generated in the combined heat and power supply device Operate so that the converted value to primary energy is minimized, taking into account supplementing the insufficient heat with auxiliary heating means when the amount of heat stored in the heat storage tank is insufficient to cover the heat demand. Therefore, even if there is a slight shortage of heat due to the capacity limitation of the heat storage tank, it is possible to cope well with the use of auxiliary heating means, select a state with less heat loss, and operate the combined heat and power unit, saving energy Can be improved satisfactorily.
[0145]
  Claims11According to the operation method of the cogeneration system according to the invention, the number of times of starting and stopping is set according to the characteristics of each combined heat and power unit to be used, the desired service life, etc., and avoiding repeated starting and stopping more than necessary. The durability of the combined heat and power supply apparatus can be prevented by preventing the life of the combined heat and power supply apparatus from being lowered early.
[Brief description of the drawings]
FIG. 1 is a system configuration diagram showing a cogeneration system according to a first embodiment of the present invention.
FIG. 2 is a block diagram.
FIG. 3 is a graph showing a change in power demand with time for explanation of an example.
FIG. 4 is a graph showing changes in heat demand over time for use in explaining examples.
FIGS. 5A and 5B are reference diagrams for explaining the operation of the first embodiment. FIGS. 5A and 5C show the correlation between the power demand and the power generation amount, respectively, and FIGS. It shows the correlation between demand and calorific value.
FIGS. 6A, 6B, 6C, and 6D are time charts showing examples of combinations of operation stop states and operation states, respectively.
7 is a graph illustrating the optimum operation state of the first embodiment, where (a) shows the correlation between the power demand and the amount of power generation, and (b) shows the correlation between the heat demand and the amount of generated heat. .
FIG. 8 is a reference diagram for explaining the operation of the second embodiment, wherein (a) and (c) show the correlation between the power demand and the amount of power generation, respectively, and (b) and (d) respectively show the heat. It shows the correlation between demand and calorific value.
FIGS. 9A and 9B are graphs illustrating the optimum operation state of the second embodiment, where FIG. 9A shows the correlation between the power demand and the amount of power generation, and FIG. 9B shows the correlation between the heat demand and the amount of generated heat. .
FIG. 10 is a reference diagram for explaining the operation of the third embodiment. (A) and (c) show the correlation between the power demand and the power generation amount, respectively, and (b) and (d) respectively show the heat. It shows the correlation between demand and calorific value.
FIGS. 11A and 11B are graphs illustrating the optimum operation state of the third embodiment, where FIG. 11A shows the correlation between the power demand and the amount of power generation, and FIG. 11B shows the correlation between the heat demand and the amount of generated heat. .
FIG. 12 is a system configuration diagram showing a cogeneration system according to a fourth embodiment of the present invention.
FIG. 13 is a block diagram of a fourth embodiment.
FIG. 14 is a block diagram of a sixth embodiment.
[Explanation of symbols]
1 ... Combined heat and power system
2 ... Thermal storage tank
8 ... Electric heater as electrothermal conversion means
19 ... Power purchase
21 ... Gas boiler as auxiliary heating means
23 ... Demand change identification means
33 ... Power selling means
41. Number of times of starting / stopping setting

Claims (11)

A combined heat and power generation device that generates the rated amount of power and heat;
A heat storage tank for storing heat generated by the cogeneration device;
Electrothermal conversion means for converting the electric power generated in the cogeneration device into heat;
Auxiliary heating means to compensate for the shortage of heat,
As a one round-life for a predetermined time, and demand change specifying means for pre-specifying the change over time in the respective heat demand and power demand in that one rotation period,
Power purchase means capable of supplying insufficient power,
While consumption is generated in said one rotation period by the cogeneration system the amount of heat corresponding to the heat demand content or the majority within said one rotation period, consumes heat became excessive in the next cycle allow the, and compensates the amount of heat of the shortage in the auxiliary heating means, said by dividing one rotation period to set the time interval available capital, stopped in a state of operating the cogeneration system in each of the divided time Assuming that the heat storage amount in the heat storage tank is 0 or more and does not exceed the maximum heat storage amount, the optimum operating state of the combination that minimizes the converted value of the overall primary energy is obtained and obtained. The cogeneration system is characterized in that the cogeneration device is operated at a rated power generation amount according to the optimum operating state, and surplus power when the power demand is smaller than the power of the rated power generation amount is converted into heat by the electrothermal conversion means. The method of operation and Deployment system. In the operation method of the cogeneration system according to claim 1,
The predetermined time as one period T, comprising a demand changes specific means to pre-specified changes over time in each heat demand and power demand within the 1 period T,
The amount of heat corresponding to the heat demand in the one cycle T or most of the heat is generated and consumed in the one cycle T by the combined heat and power supply device, and excess heat is consumed in the next cycle. And the supplementary heating means compensates for the shortage of heat, divides the one period T into set time intervals d, and stops the state in which the combined heat and power device is operated at each divided time. Assuming the state, the fluctuation value S (t + n · d) of the heat storage amount in the heat storage tank always satisfies the following conditional expression (1), and the converted value PE [Expression (4)] of the following primary energy is minimum. The combined operation of the thermoelectric power supply device is operated at the rated power generation amount according to the determined optimal operation state, and surplus power when the power demand is smaller than the power of the rated power generation amount is calculated by the electrothermal conversion means. The method of operating a cogeneration system and converting the.

Here, S [t + (n−1) d] indicates the amount of heat stored in the heat storage tank at the start of operation for each divided time. In addition, n is a positive integer of 1 to T / d, h (t ′) is a function indicating a temporal change in heat demand specified in advance, and ex (t ′) is a release from the system. The amount of heat. S _max indicates the maximum heat storage amount of the heat storage tank.
HT _n indicates the amount of heat acquired within the divided time interval d, and is expressed by the following equation (2).

Here, F indicates the power of the rated power generation amount, and k indicates the thermoelectric ratio. H _n is a conversion heat amount obtained by converting surplus electric power into heat by the electrothermal conversion means, and integrates F> E _n (t ′), and is expressed by the following equation (3).

However, if e (t ′) <F, E _n (t ′) = e (t ′)
If e (t ′) ≧ F, E _n (t ′) = F
Here, E _n (t ′) is the rated power amount when the load power exceeds the power of the rated power generation amount, and is the power amount that becomes the load power amount when the load power is smaller than the rated power, and e ( t ′) is a function indicating a change with time in power demand (load power) specified in advance.
In the above equation (2), BO (t ′) indicates a function in the case where the auxiliary heating means is activated so as to compensate for the shortage when the shortage of heat occurs.
PE = ΣPE _n = ΣGI _n · α + ΣBI _n · α '+ ΣBE _n · β (4)
Here, ΣPE _n is the total primary energy of n = 1 to T / d. GI _n is a fuel supply amount required for the operation of the combined heat and power supply device, and is expressed by the following equation (5), α is a converted value to the primary energy of the fuel, and ΣGI _n · α is n = 1 to T The sum of / d is obtained. BI _n is the fuel supply amount required for the operation of the auxiliary heating means, α ′ is a converted value to the primary energy of the fuel, and ΣBI _n · α ′ is the sum of n = 1 to T / d Yes.

Here, GI (t ′) is the fuel supply amount specified by the combined heat and power supply device to be used, and is zero in the operation stop state.
ΣBE _n is an input amount of insufficient power within a predetermined time T, which is one cycle T, and is expressed by the following equation (6), and β is a converted value of power to primary energy, n = 1 to T / d.

Here, GP is the power generation amount of the combined heat and power supply device, and is expressed by the following equation (7).

Here, E (t ′) is the rated power amount when the load power exceeds the power of the rated power generation amount, and is the power amount that becomes the load power amount when the load power is smaller than the rated power. A cogeneration device that generates power and heat that can be operated according to the load power when the load power is less than the rated power generation amount,
A heat storage tank for storing heat generated by the cogeneration device;
Auxiliary heating means to compensate for the shortage of heat,
As a one round-life for a predetermined time, and demand change specifying means for pre-specifying the change over time in the respective heat demand and power demand in that one rotation period,
Power purchase means capable of supplying insufficient power,
While consumption is generated in said one rotation period by the cogeneration system the amount of heat corresponding to the heat demand content in said one rotation period, allowed to consume the heat becomes excessive in the next cycle and, and compensates for the amount of heat shortage in the auxiliary heating means, and a state where the by dividing one rotation period to set the time interval available capital, stopped in a state of operating the cogeneration system in each of the divided time Assuming that the heat storage amount in the heat storage tank is 0 or more and does not exceed the maximum heat storage amount, the optimum operation state of the combination that minimizes the converted value of the overall primary energy is obtained, and the optimum operation obtained Depending on the state, the cogeneration system is operated with the rated power generation amount and when the power demand is smaller than the rated power generation amount, the cogeneration system is operated by following the change in the power demand. The rolling method. In the operation method of the cogeneration system according to claim 3,
The predetermined time as one period T, comprising a demand changes specific means to pre-specified changes over time in each heat demand and power demand within the 1 period T,
The amount of heat corresponding to the heat demand within one cycle T is generated and consumed within the one cycle T by the combined heat and power supply device, and excess heat is allowed to be consumed in the next cycle. And supplementing the deficient amount of heat with the auxiliary heating means, dividing the one period T into set time intervals d, and operating and stopping the combined heat and power device at each divided time. Assuming that the variation value S (t + n · d) of the heat storage amount in the heat storage tank always satisfies the following conditional expression (8), and the following primary energy conversion value PE [Expression (10)] is minimized. The optimum operating state is obtained, and the combined heat and power unit is operated at the rated power generation amount according to the determined optimum operating state, and when the power demand is smaller than the rated power generation amount, the operation is performed following the change in the power demand. The method of operating a cogeneration system comprising.

Here, S [t + (n−1) d] indicates the amount of heat stored in the heat storage tank at the start of operation for each divided time. In addition, n is a positive integer of 1 to T / d, h (t ′) is a function indicating a temporal change in heat demand specified in advance, and ex (t ′) is a release from the system. The amount of heat. Smax indicates the maximum heat storage amount of the heat storage tank.
HT _n indicates the amount of heat acquired within the divided time interval d, and is expressed by the following equation (9).

Here, E _n (t ′) is the rated power amount when the load power exceeds the rated power generation amount, and is the power amount that becomes the load power amount when the load power is smaller than the rated power. B [E _n (t ′)] indicates the amount of heat generated by the combined heat and power device at the amount of power E _n (t ′).
BO (t ′) represents a function in the case where the auxiliary heating means is activated so as to compensate for the shortage when a shortage of heat occurs.
PE = ΣPE _n = ΣGI _n · α + ΣBI _n · α ′ + ΣBE _n · β (10)
Here, ΣPE _n is the total primary energy of n = 1 to T / d. GI _n is a fuel supply amount required for the operation of the cogeneration system, is represented by the following formula (5a), also, alpha is the conversion value of the primary energy of the fuel, the ΣGI _n · α _n = 1~T The sum of / d is obtained. BI _n is the fuel supply amount required for the operation of the auxiliary heating means, α ′ is a converted value to the primary energy of the fuel, and ΣBI _n · α ′ is the sum of n = 1 to T / d Yes.

Here, GI (t ′) is the fuel supply amount specified by the combined heat and power supply device to be used, and is zero in the operation stop state.
ΣBE _n is an input amount of insufficient power within a predetermined time T that is one cycle T, and is expressed by the following equation (11), and β is a converted value of power to primary energy, n = 1 to T / d.

Here, GP is a power generation amount of the combined heat and power supply device, and is represented by the following equation (12).

Here, E (t ′) is the rated power amount when the load power exceeds the power of the rated power generation amount, and is the power amount that becomes the load power amount when the load power is smaller than the rated power, and e (t ') Is a function indicating a change with time in power demand (load power) specified in advance. A combined heat and power device that operates with the power generation amount set in multiple stages and generates the power and heat of the set power generation amount,
A heat storage tank for storing heat generated by the cogeneration device;
Electrothermal conversion means for converting the electric power generated in the cogeneration device into heat;
Auxiliary heating means to compensate for the shortage of heat,
As a one round-life for a predetermined time, and demand change specifying means for pre-specifying the change over time in the respective heat demand and power demand of one round-life Contact and following one round Kiso been within which each,
Power purchase means capable of supplying insufficient power,
While consumption is generated in said one rotation period by the cogeneration system the amount of heat corresponding to the heat demand content in said one rotation period, allowed to consume the heat becomes excessive in the next cycle and, and compensates for the amount of heat shortage in the auxiliary heating means, said by dividing one rotation period to set the time interval available capital, each set amount of power generated by the plurality of stages of the cogeneration unit in each of the divided time Assuming the operation state and the stop state, the heat storage amount in the heat storage tank is not less than 0 and does not exceed the maximum heat storage amount, and the optimum operation state of the combination in which the converted value of the primary energy is minimized And operating the combined heat and power supply device with a plurality of rated power generation amounts and converting surplus power when the power demand is smaller than a set power generation amount into heat by the electrothermal conversion means according to the determined optimum operating state. With features Cogeneration system method of operation that. In the operation method of the cogeneration system according to claim 5,
The predetermined time as one cycle T, with its one period T and the next one period T heat demand and power demand respectively demand changes specific means to pre-specified temporal changes in the respective
The amount of heat corresponding to the heat demand within one cycle T is generated and consumed within the one cycle T by the combined heat and power supply device, and excess heat is allowed to be consumed in the next cycle. In addition, the shortage of heat is supplemented by the auxiliary heating means, and the one cycle T is divided every set time interval d, and the combined heat and power unit is operated at each of the set power generation amounts in a plurality of stages at each divided time. Assuming a state to be stopped and a state to be stopped, the fluctuation value S (t + n · d) of the heat storage amount in the heat storage tank always satisfies the following conditional expression (13), and the converted value PE of the following primary energy [Expression (16 )] Is determined as the optimum operating state of the combination that minimizes the surplus power when the combined heat and power unit is operated with the rated power generation amount in a plurality of stages and the power demand is smaller than the set power generation amount according to the determined optimum operating state. The method of operating a cogeneration system and converting into heat by said electrothermal converter.

Here, S [t + (n−1) d] indicates the amount of heat stored in the heat storage tank at the start of operation for each divided time. In addition, n is a positive integer of 1 to T / d, h (t ′) is a function indicating a temporal change in heat demand specified in advance, and ex (t ′) is a release from the system. The amount of heat. S _max indicates the maximum heat storage amount of the heat storage tank.
HT _n indicates the amount of heat acquired within the divided time interval d, and is expressed by the following equation (14).

Here, F _m is the set power amount, k _m represents the thermoelectric ratio at the set power amount F _m respectively. m is a positive integer greater than or equal to 2 and up to the set number of power generation levels. H _n is the amount of converted heat obtained by converting surplus power into heat by the electrothermal conversion means, and integrates F _m > E _n (t ′), and is expressed by the following equation (15).

However, if e (t ′) <F _m , E _n (t ′) = e (t ′)
If e (t ′) ≧ F _m , E _n (t ′) = F _m
Here, E _n (t ′) is the set power amount when the load power exceeds the set power generation amount Fm, and is the power amount that becomes the load power amount when the load power is smaller than the set power generation amount Fm. (T ′) is a function indicating a change with time in power demand (load power) specified in advance.
In the above equation (14), BO (t ′) represents a function when the auxiliary heating means is activated so as to compensate for the shortage when the shortage of heat occurs.
PE = ΣPE _n = ΣGI _n · α + ΣBI _n · α '+ ΣBE _n · β (16)
Here, ΣPE _n is the total primary energy of n = 1 to T / d. GI _n is a fuel supply amount required for the operation of the combined heat and power supply device, and is expressed by the following equation (17), α is a converted value to the primary energy of the fuel, and ΣGI _n · α is n = 1 to T The sum of / d is obtained. BI _n is the fuel supply amount required for the operation of the auxiliary heating means, α ′ is a converted value to the primary energy of the fuel, and ΣBI _n · α ′ is the sum of n = 1 to T / d Yes.

Here, GI (t ′) is the fuel supply amount specified by the combined heat and power supply device to be used, and is zero in the operation stop state.
ΣBE _n is an input amount of the shortage of electric power within a predetermined time T that is one cycle T, and is expressed by the following equation (18), and β is a converted value of electric power to primary energy, and n = 1 to T / d.

Here, GP is a power generation amount of the combined heat and power supply device, and is represented by the following equation (19).

Here, E (t ′) is a power amount that becomes the set power amount when the load power exceeds the set power generation amount Fm, and becomes the load power amount when the load power is smaller than the set power generation amount Fm. A combined heat and power generation device that generates the rated amount of power and heat;
A heat storage tank for storing heat generated by the cogeneration device;
Power selling means for selling the electric power generated by the cogeneration device to a third party;
Auxiliary heating means to compensate for the shortage of heat,
As a one round-life for a predetermined time, and demand change specifying means for pre-specifying the change over time in the respective heat demand and power demand in that one rotation period,
Power purchase means capable of supplying insufficient power,
While consumption is generated in said one rotation period by the cogeneration system the amount of heat corresponding to the heat demand content or the majority within said one rotation period, consumes heat became excessive in the next cycle allow the, and compensates the amount of heat of the shortage in the auxiliary heating means, said by dividing one rotation period to set the time interval available capital, stopped in a state of operating the cogeneration system in each of the divided time The optimal operating state of the combination in which the converted value of the primary energy is minimized is set so that the fluctuation value of the heat storage amount in the heat storage tank is not less than 0 and does not exceed the maximum heat storage amount. And operating the combined heat and power supply device with a rated power generation amount according to the determined optimum operating state and selling surplus power when the power demand is smaller than the power of the rated power generation amount to the third party by the power selling means. Koji Method of operating a configuration system. In the operation method of the cogeneration system according to claim 7,
The predetermined time as one period T, comprising a demand changes specific means to pre-specified changes over time in each heat demand and power demand within the 1 period T,
The amount of heat corresponding to the heat demand in the one cycle T or most of the heat is generated and consumed in the one cycle T by the combined heat and power supply device, and excess heat is consumed in the next cycle. And the supplementary heating means compensates for the shortage of heat, divides the one period T into set time intervals d, and stops the state in which the combined heat and power device is operated at each divided time. Assuming the state, the fluctuation value S (t + n · d) of the heat storage amount in the heat storage tank always satisfies the following conditional expression (20), and the converted value PE of the following primary energy [Expression (22)] is minimum. The combined operation of the combined heat and power unit is operated at the rated power generation amount, and surplus power when the power demand is smaller than the rated power generation power is The method of operating a cogeneration system, wherein a sell three parties.

Here, S [t + (n−1) d] indicates the amount of heat stored in the heat storage tank at the start of operation for each divided time. In addition, n is a positive integer of 1 to T / d, h (t ′) is a function indicating a temporal change in heat demand specified in advance, and ex (t ′) is a release from the system. The amount of heat. Smax indicates the maximum heat storage amount of the heat storage tank.
HT _n indicates the amount of heat acquired within the divided time interval d, and is expressed by the following equation (21).

Here, F indicates the power of the rated power generation amount, and k indicates the thermoelectric ratio.
In the above equation (21), BO (t ′) represents a function in the case where the auxiliary heating means is activated so as to compensate for the shortage when the shortage of heat occurs.
PE = ΣPE _n
= ΣGI _n · α + ΣBI _n · α '+ ΣBE _n · β-ΣSE _n · γ (22)
Here, ΣPE _n is the total primary energy of n = 1 to T / d. GI _n is a fuel supply amount required for the operation of the combined heat and power supply device, and is expressed by the following equation (23), α is a converted value to the primary energy of fuel, and ΣGI _n · α is n = 1 to T The sum of / d is obtained. BI _n is the fuel supply amount required for the operation of the auxiliary heating means, α ′ is a converted value to the primary energy of the fuel, and ΣBI _n · α ′ is the sum of n = 1 to T / d Yes.

Here, GI (t ′) is the fuel supply amount specified by the combined heat and power supply device to be used, and is zero in the operation stop state.
ΣBE _n is an input amount of insufficient power within a predetermined time T that is one cycle T, and is expressed by the following equation (24), and β is a converted value of power to primary energy, n = 1 to T / d.

Here, GP is the power generation amount of the combined heat and power supply device, and is represented by the following equation (25).

Here, E (t ′) is the rated power amount when the load power exceeds the power of the rated power generation amount, and is the power amount that becomes the load power amount when the load power is smaller than the rated power. Further, ΣSE _n is the surplus power amount sold to the third party by the power selling means, and is integrated by F> E _n (t ′), expressed by the following equation (26), and γ is the first This is a conversion value obtained by converting the price when selling to three parties into primary energy, and the sum of n = 1 to T / d is obtained.

However, if e (t ′) <F, E _n (t ′) = e (t ′)
If e (t ′) ≧ F, E _n (t ′) = F
Here, E _n (t ′) is the rated power amount when the load power exceeds the power of the rated power generation amount, and is the power amount that becomes the load power amount when the load power is smaller than the rated power, and e ( t ′) is a function indicating a change with time in power demand (load power) specified in advance. A combined heat and power device that operates with the power generation amount set in multiple stages and generates the power and heat of the set power generation amount,
A heat storage tank for storing heat generated by the cogeneration device;
Power selling means for selling the electric power generated by the cogeneration device to a third party;
Auxiliary heating means to compensate for the shortage of heat,
As a one round-life for a predetermined time, and demand change specifying means for pre-specifying the change over time in the respective heat demand and power demand of one round-life Contact and following one round Kiso been within which each,
Power purchase means capable of supplying insufficient power,
While consumption is generated in said one rotation period by the cogeneration system the amount of heat corresponding to the heat demand content in said one rotation period, allowed to consume the heat becomes excessive in the next cycle and, and compensates for the amount of heat shortage in the auxiliary heating means, said by dividing one rotation period to set the time interval available capital, each set amount of power generated by the plurality of stages of the cogeneration unit in each of the divided time Assuming the operation state and the stop state, the heat storage amount in the heat storage tank is 0 or more and does not exceed the maximum heat storage amount, and the optimum operation state of the combination in which the converted value of the primary energy is minimized And operating the combined heat and power supply device with a plurality of rated power generation amounts and selling the surplus power when the power demand is smaller than the set power generation amount to the third party by the power selling means according to the determined optimum operating state. It is characterized by Method of operating a cogeneration system. In the operation method of the cogeneration system according to claim 9,
The predetermined time as one cycle T, with its one period T and the next one period T heat demand and power demand respectively demand changes specific means to pre-specified temporal changes in the respective
The amount of heat corresponding to the heat demand within one cycle T is generated and consumed within the one cycle T by the combined heat and power supply device, and excess heat is allowed to be consumed in the next cycle. In addition, the shortage of heat is supplemented by the auxiliary heating means, and the one cycle T is divided every set time interval d, and the combined heat and power unit is operated at each of the set power generation amounts in a plurality of stages at each divided time. Assuming the state of being stopped and the state of stopping, the fluctuation value S (t + n · d) of the heat storage amount in the heat storage tank always satisfies the following conditional expression (27), and the converted value PE of the following primary energy [Expression (29 )] Is determined as the optimum operating state of the combination that minimizes the surplus power when the combined heat and power unit is operated with the rated power generation amount in a plurality of stages and the power demand is smaller than the set power generation amount according to the determined optimum operating state. The method of operating a cogeneration system, characterized in that sell to a third party by the power selling unit.

Here, S [t + (n−1) d] indicates the amount of heat stored in the heat storage tank at the start of operation for each divided time. In addition, n is a positive integer of 1 to T / d, h (t ′) is a function indicating a temporal change in heat demand specified in advance, and ex (t ′) is a release from the system. The amount of heat. S _max indicates the maximum heat storage amount of the heat storage tank.
HTn represents the amount of heat acquired within the divided time interval d, and is expressed by the following equation (28).

Here, F _m is the set power amount, k _m represents the thermoelectric ratio at the set power amount F _m respectively. m is a positive integer greater than or equal to 2 and up to the set number of power generation levels.
In the above equation (28), BO (t ′) represents a function in the case where the auxiliary heating means is activated so as to compensate for the shortage when the shortage of heat occurs.
PE = ΣPE _n
= ΣGI _n · α + ΣBI _n · α '+ ΣBE _n · β-ΣSE _n · γ (29)
Here, ΣPE _n is the total primary energy of n = 1 to T / d. GI _n is a fuel supply amount required for the operation of the combined heat and power supply device, and is expressed by the following equation (30), α is a converted value to the primary energy of fuel, and ΣGI _n · α is n = 1 to T The sum of / d is obtained. BI _n is the fuel supply amount required for the operation of the auxiliary heating means, α ′ is a converted value to the primary energy of the fuel, and ΣBI _n · α ′ is the sum of n = 1 to T / d Yes.

Here, GI (t ′) is the fuel supply amount specified by the combined heat and power supply device to be used, and is zero in the operation stop state.
ΣBE _n is an input amount of insufficient power within a predetermined time T that is one cycle T, and is expressed by the following equation (31), and β is a converted value of power to primary energy, n = 1 to T / d.

Here, GP is the power generation amount of the combined heat and power supply device, and is represented by the following equation (32).

Here, E (t ′) is the rated power amount when the load power exceeds the power of the rated power generation amount, and is the power amount that becomes the load power amount when the load power is smaller than the rated power. Further, ΣSE _n is the surplus power amount sold to the third party by the power selling means, and is integrated by F> E _n (t ′), expressed by the following equation (33), and γ is the first This is a conversion value obtained by converting the price when selling to three parties into primary energy, and the sum of n = 1 to T / d is obtained.

However, if e (t ′) <F _m , E _n (t ′) = e (t ′)
If e (t ′) ≧ F _m , E _n (t ′) = F
Here, E _n (t ′) is the set power amount when the load power exceeds the set power generation amount Fm, and is the power amount that becomes the load power amount when the load power is smaller than the set power generation amount F _m . e (t ′) is a function indicating a change with time in power demand (load power) specified in advance. The operation of the cogeneration system according to any one of claims 1, 2, 3, 4, 5 , 6, 7, 8, 9, and 10. In the method
A combination that includes start / stop times setting means for setting the number of start / stops in one cycle of the combined heat and power supply device, and the number of start / stops in one cycle of the combined heat and power supply device is equal to or less than the set number of times, and the primary energy conversion value PE is minimized. A cogeneration system operation method that seeks the optimal operating state of a vehicle.

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