JP3744721B2

JP3744721B2 - Flexible conductor and flexible connecting member

Info

Publication number: JP3744721B2
Application number: JP12070999A
Authority: JP
Inventors: 伸治佐藤; 健一小山
Original assignee: Mitsubishi Electric Corp
Current assignee: Mitsubishi Electric Corp
Priority date: 1999-04-27
Filing date: 1999-04-27
Publication date: 2006-02-15
Anticipated expiration: 2019-04-27
Also published as: JP2000316224A

Description

【０００１】
【発明の属する技術分野】
本発明は、高電圧大電流が負荷される二電路間を電気的に接続し、各電路の変位による応力を吸収する可撓性導体及び可撓性接続部材に関し、特に、高真空下で使用される、帯状の導体を積層した可撓性導体及び可撓性接続部材に関する。
【０００２】
【従来の技術】
受変電設備として広く用いられている開閉装置は、接地容器の内部に遮断器、断路器、接地開閉器などの要素機器を収容した構成になっている。要素機器の中には例えば遮断器の接点開閉のように電路に変位が生じるものがある。この遮断器と他の電路との間の接続には可撓性を有する導体が使用される。これは、接続された他の電路に遮断器の可動側電極の変位による不要な応力や衝撃力を伝達させないためである。また可撓性導体は、上述した接点開閉のような外部機械力による電路の変位に対してだけでなく、温度変化による熱応力や振動、さらに取り付け誤差による歪み応力を他の電路に伝えないためにも使用されることがある。
【０００３】
可撓性導体に使用される材質には、開閉装置が大電流を導通させるものであるため、抵抗率が低い銅の使用が一般的である。この銅に可撓性を発現させるため、銅を細線状にして束ねたもの、又は箔状にして積層したものが用いられる。可撓性導体を構成する個々の線状導体または箔状導体は、長期間の使用により前者の場合は素線のばらけ，飛び出し，断線などが生じ、後者の場合は箔の不揃いな撓みが生じる。開閉装置は高電圧で動作するため、このような不均一が生じた部位の先端部位又は鋭利な部位には高電界が生じる。また、たとえ長期使用に伴う形状変化がなくても、箔状導体の端部，縁部などは高電界が発生し易い形状であり、このような高圧充電部の高電界部と接地電位である容器壁面との間で地絡放電が生じる虞がある。３相交流型の開閉装置の場合、異相充電部の間の高電界部にて相関放電が生じる虞もある。また容器内が絶縁ガス雰囲気の場合は、絶縁破壊にいたらなくても部分放電が生じ、不純物ガスの発生により絶縁性能が徐々に低下していく。
【０００４】
これを解決するために、可撓性導体の不均一部分に高電界部を発生させない先行例として特開平１−255410号公報が提案されている。図１６は、その可撓性導体の構造を示す部分断面図である。接続導体１００は、導体細線で形成された集合導体１１により二電路間の導通を果たしており、接続導体１００の両端１２，１３は集合導体１１が密集結束されて他の電路端末１６，１７に夫々接続されている。集合導体１１の外周にはそのほぼ全長にわたり、外面が平滑な筒状の導体製のシールド部材２１，２２が集合導体１１から適宜間隔を有して被覆されている。これらの部材は、全て絶縁ガス雰囲気中に設置される。
【０００５】
また、このシールド部材２１，２２と集合導体１１との間に絶縁物を介装した構造の可撓性導体も提案されている（公開実用平成１−86429 号公報）。このような絶縁ガス雰囲気で使用される接続導体１００は、集合導体１１を構成する個々の細線がばらけたり飛び出した場合でも、シールド部材２１，２２によって導体細線自身に高電界が発生しないようになっており、絶縁破壊や部分放電の発生を抑制できる。
【０００６】
【発明が解決しようとする課題】
上述した如き導体製のシールド部材の効果を詳述すると次の通りである。絶縁ガス内の可撓性導体の周囲に接地導体が近接配置されており、両者の間にシールド部材が存在しない場合は可撓性導体の端部に高い電界が発生し、電界分布は不平等電界となる。そして両者の間にシールド部材を介装した場合は、可撓性導体の端部がシールド部材で覆われ、電界分布は平等電界に近い状態になる。SF₆を代表とするガス絶縁媒体の場合、平等電界分布下では高い絶縁性能を発揮するが、不平等電界下では平等電界分布下ほどの絶縁性能は現れない。従って、シールド部材の設置によってガス絶縁の優れた特徴が引き出され、絶縁破壊や部分放電が防止できることが判る。
【０００７】
一方、容器内の絶縁媒体にガスではなく圧力10^-6Torr程度の高真空を利用する場合がある。一般に、高真空中の絶縁破壊特性は以下の点でガス中のそれと異なる。上述した構造のシールド部材を配して平等電界を形成した場合、シールド部材表面上で最大電界の例えば９０％までの値をとる部分の面積は、シールド部材を配さない場合の可撓性導体表面において最大電界の９０％までの値をとる部分の面積よりも格段に大きくなる。この最大電界とほぼ同等の電界を有する部分の面積の増加は、絶縁破壊を引き起こす起点となる弱点因子の数の増加を意味する。ガス中では、弱点因子数を増加させてでも不平等電界を形成しない方が、結果的には絶縁破壊特性、即ち絶縁破壊電圧が向上する。これに対し、高真空中では、ガス中ほど平等電界でなくても良好な絶縁破壊電圧を維持することができる。すなわち弱点因子数をむやみに増加させず不平等電界のままにしておく方が、絶縁破壊電圧が高くなる場合がある。
【０００８】
このように高真空下とガス下とでは平等電界の程度、又は電極面積が破壊電圧に対して与える影響の度合いが異なるために、ガス絶縁機器への適用を意図した上述の先行例は、真空絶縁機器に対しては同様の効果を発揮できないという問題があった。
【０００９】
本発明は、かかる事情に鑑みてなされたものであり、高真空下で使用される可撓性導体又は可撓性接続部材の絶縁破壊を防止するために、絶縁補助帯，螺旋導体，電界緩和シールド部又は絶縁部を適所に配し、その結果、高真空下での耐電圧が向上し、真空放電を防止して、機器の小寸法化の実現と信頼性を確保できる可撓性導体及び可撓性接続部材を提供することを目的とする。
【００１０】
【課題を解決するための手段】
第１発明に係る可撓性導体は、複数の導電帯が積層され、二電路間を電気的に接続する導電帯部と、該導電帯部の積層方向の両外側に夫々配され、前記導電帯と略同程度の弾性を有する絶縁補助帯とを備えることを特徴とする。
【００１１】
第２発明に係る可撓性導体は、複数の導電帯が積層され、二電路間を電気的に接続する導電帯部と、前記導電帯よりも広い幅寸法を有し、幅方向の端縁が前記導電帯よりも突出すべく前記導電帯の積層間に夫々配された絶縁補助帯とを備えることを特徴とする。
【００１２】
第３発明に係る可撓性導体は、第１又は第２発明において、導電帯は銅製であり、絶縁補助帯はステンレス鋼製であることを特徴とする。
【００１３】
また、第４発明に係る可撓性導体は、二電路間を電気的に接続するための複数の導電帯を積層した導電帯部を備え、該導電帯部は積層方向の中央側に両端側よりも広い幅寸法を有する前記導電帯を配してあることを特徴とする。
【００１４】
第５発明に係る可撓性導体は、第４発明において、導電帯部は、導電帯の幅寸法を積層方向の両端側から中央側に従って広くなしてあることを特徴とする。
【００１５】
第６発明に係る可撓性導体は、第４発明において、導電帯部は、積層方向の中央側に最も広い幅寸法を有する複数の導電帯を配してあることを特徴とする。
【００１６】
第７発明に係る可撓性接続部材は、第１乃至第６発明のいずれかの可撓性導体と、該可撓性導体の外周に螺旋状に巻回され、その一端は前記可撓性導体の端部に電気的に接続され、他端は自由端である螺旋導体とを備えることを特徴とする。
【００１７】
第８発明に係る可撓性接続部材は、二電路間を電気的に接続するための、複数の導電帯を積層してなる可撓性導体と、導電帯の幅方向端面を覆い、積層方向端面の前記導電帯を露出せしめる電界緩和シールド部とを備えることを特徴とする。
【００１８】
第９発明に係る可撓性接続部材は、第１乃至第６発明のいずれかに記載の可撓性導体と、導電帯の幅方向端面を覆い、積層方向端面の前記導電帯を露出せしめる電界緩和シールド部とを備えることを特徴とする。
【００１９】
第１０発明に係る可撓性接続部材は、第８又は第９発明において、電界緩和シールド部は、導電帯の長さ方向両端側に夫々配され、各電界緩和シールド部は前記導電帯の幅方向両端面に夫々対向配置された導電板であることを特徴とする。
【００２０】
第１１発明に係る可撓性接続部材は、二電路間を電気的に接続するための、複数の導電帯を積層してなる可撓性導体と、前記導電帯の幅方向端面に夫々対向配置された絶縁部とを備えることを特徴とする。
【００２１】
第１発明の可撓性導体にあっては、例えば銅箔のような導電帯を積層した導電帯部の積層方向両外側に、ステンレス鋼製の絶縁補助帯を配することにより、可撓性導体と異電位部材（例えば容器壁面，異相高圧充電部など）との間の絶縁を維持できる電圧を高くすることができる。これは、図３に示すように、高真空中に置かれた二つの電極間の絶縁破壊電圧は、電極がステンレス鋼である場合の方が銅である場合よりも高いためである。
【００２２】
導電帯の積層による可撓性導体は、撓みが生じる積層方向両外面及び導電帯の端縁で高い電界が生じる。第１発明では、高い電界強度の部分に絶縁補助帯を配することにより可撓性導体の耐電圧特性が向上し、可撓性導体の絶縁破壊が防止される。また、絶縁補助帯の弾性を導電帯のそれと同程度とすることにより、絶縁補助帯が導電帯の変位を阻害せず、且つ絶縁補助帯が導電帯から離れて変位することがない。この結果、可撓性導体における絶縁破壊の発生が防止でき、機器の小寸法化を図り、高信頼性を得ることができる。なお、絶縁補助帯はステンレス鋼に限るものではなく、真空下の耐電圧が導電帯よりも相対的に高く、且つ可撓性を有する導体であれば良い。
【００２３】
第２発明にあっては、導電帯よりも絶縁補助帯の幅を大きくすることにより、絶縁補助帯の幅方向端縁が露出し、導電帯の端縁は絶縁補助帯の端縁よりも内側に位置し、露出しない。このため導電帯の端縁では高電界が発生せず、絶縁補助帯の端縁にのみ高電界が発生するので、両者の幅が等しい従来の可撓性導体よりも、また絶縁補助帯を配さない可撓性導体よりも真空下での耐電圧特性が向上する。
【００２４】
第３発明にあっては、導電帯を銅で、絶縁補助帯をステンレス鋼で形成している。前述したとおりステンレス鋼は銅よりも真空下での耐電圧が高いので、高電界が発生しても絶縁性が高い可撓性導体が得られる。
【００２５】
第４又は第５発明にあっては、複数の導電帯を積層方向の中央部ほど幅広であるように積層してあるので、積層方向の両外側の導電帯は中央部よりも接地電位導体からの距離が遠くなり、中央部よりも電界強度が低くなる。これにより導電帯の真空下での耐電圧特性が向上し、電界破壊が防止される。
【００２６】
第６発明にあっては、上記同様、積層方向両外側の導電帯の電界強度が低くなり、絶縁破壊が防止される。さらに、中央部の複数の導電帯の幅が一定であるので、幅が一定の導電帯の枚数を調節することにより、通電可能な電流の大きさが異なる可撓性導体に共通に使用できる。
【００２７】
第７発明の可撓性接続部材にあっては、第１乃至第６発明で述べたような耐電圧特性が向上される構成、又は表面の電界強度を低減できる構成の可撓性導体に、線状又は帯状の導体を螺旋状に巻回してあるので、可撓性導体に発生する表面の電界強度を低減できる。また、螺旋導体は螺旋状に巻回してあるので、可撓性導体の変位に追従できる。
【００２８】
可撓性導体の全表面のうち電界強度が高くなるのは導電帯の端部である。第８発明にあっては、導電帯の幅方向の端面を電界緩和シールド部で覆うことにより、可撓性接続部材の真空下での耐電圧を高め、絶縁破壊を防止する。また第９発明にあっては、第１乃至第６発明で述べたような耐電圧特性が向上される構成、又は表面の電界強度を低減できる構成の可撓性導体に、導電帯の幅方向端面を覆う電界緩和シールドを配してあるので、さらに可撓性接続部材の耐電圧特性が向上する。
【００２９】
第１０発明にあっては、電界緩和シールド部は導体製であるので、電界緩和シールド部に高電界が発生し、可撓性導体の電界強度が低減するので絶縁破壊が防止される。
【００３０】
可撓性接続部材の導電帯の幅方向端面から放電が生じる場合、この端面の電界強度が非常に高くなって電界放出が生じ、その電子が相手側の導体へ加速されながら移動することが放電の引き金になると考えられる。第１１発明にあっては、導電帯の端縁部を絶縁部で覆っているので、端縁部から放出された電界放出電子が絶縁部で遮蔽され、相手側導体へ移動できない。これにより真空放電が防止される。
【００３１】
【発明の実施の形態】
以下、本発明をその実施の形態を示す図面に基づき具体的に説明する。
実施の形態１．
本発明の実施の形態１による可撓性導体を図に基づいて説明する。図１は実施の形態１に係る可撓性導体２０の斜視図、図２は図１のII−II線から見た断面図である。図１に示すように、導電帯部１０は、帯状の銅箔１の数十枚が厚さ方向に所定の間隙を有して積層されて形成されている。銅箔１は無酸素銅で形成されており、長さ150mm ，幅Ｗ50mm及び厚さ0.1mm を有している。導電帯部１０の積層方向両外側、即ち銅箔１，１…の上下側にステンレス鋼箔２ａ，２ｂ（絶縁補助帯）が夫々積層されている。ステンレス鋼箔２ａ，２ｂは、その長さ及び幅寸法は銅箔１と同一寸法である。また、ステンレス鋼箔２ａ，２ｂの厚さは、銅箔１と同程度の弾性を得る寸法、例えば本実施の形態では0.1mm に形成されている。また図２に示すように、銅箔１及びステンレス鋼箔２ａ，２ｂは、幅方向の端面を揃えて積層されている。なお、銅箔１の寸法は、通流電流の大きさ、接続する二電路間の距離などにより適宜の値に設定されることが好ましく、上記寸法に限るものではない。
【００３２】
積層された銅箔１，１…及びステンレス鋼箔２ａ，２ｂは、長さ方向の両端側で除々に間隔を狭めて互いに接触せしめ、箔押さえ材３，３によって固着されている。箔押さえ材３は、可撓性導体２０が電流導通部材であることから抵抗率の低い銅で形成されている。箔押さえ材３の固着方法には、かしめによる固着，ネジ締め又はボルト締めなどがあるが、高真空中での使用の際はろう付けで固着する方法が好ましい。このろう付けは、図示しない他の部材のろう付け工程時に同時に行なっても良い。
【００３３】
箔押さえ材３の夫々は電路端末４，４の一端に接続されている。電路端末４は図示しない他の電路の一部で、例えば遮断器又は断路器が電路端末４の他端に接続される。また図２に示すように、接地電位導体９は、銅箔１及びステンレス鋼箔２ａ，２ｂの幅方向端面に対向する位置に配されている。接地電位導体９は例えば真空容器の内壁面であり、図１では煩雑さを理由に省略している。なお、図２では、接地電位導体９は銅箔１及びステンレス鋼箔２ａ，２ｂの幅方向の片側のみに位置しているが、両側に位置する場合もある。また、接地電位導体９のかわりに他の可撓性導体の端部が配置されることもある。
【００３４】
以上の如き構成の可撓性導体２０は、真空下で動作する開閉装置の例えば遮断器と他の電路との間に接続される。遮断器の接点開閉時に電路に変位が生じた際に、接続先の電路にその応力を伝達しないように可撓性導体が変位するようになっている。本実施の形態の可撓性導体２０は、高電界が発生する箇所である銅箔１，１…の積層方向の上下を、ステンレス鋼箔２ａ，２ｂで覆っている。図３は、距離5mm の準平等電界ギャップのインパルス破壊電圧を10^-6Torrの高真空下で測定した結果を示した棒グラフである。銅箔１を形成している無酸素銅とステンレス鋼箔２ａ，２ｂを形成しているステンレス鋼とについて測定しており、縦軸は破壊電圧を示している。このグラフから、ステンレス鋼が無酸素銅の約１．３倍の破壊電圧を示していることが判る。この耐電圧の大小関係は本実施の形態の箔の端部のような不平等電界下でも同じである。
【００３５】
このように、真空下で銅よりも耐電圧が高いステンレス鋼箔２ａ，２ｂで、導電帯部１０の高電界が発生する積層方向の上下箇所のみを覆っているので、最大電界強度を有する面積が過大にならない。従って、本実施の形態の可撓性導体２０は銅箔１のみの可撓性導体よりも高い耐電圧を有し、耐電圧特性を向上させる。また、ステンレス鋼箔２ａ，２ｂは、銅箔１と銅程度の弾性を有しているので、ステンレス鋼箔２ａ，２ｂが銅箔１の変位を阻害することがなく、また、銅箔１から離れて変位することもない。
【００３６】
従って、本実施の形態の可撓性導体２０は、真空下での耐電圧特性が良好であるので、接地された真空容器に対する地絡放電を防止できる。また３相交流回路に使用された場合に近傍に配置した他相の充電部との間の相間放電を防止できる。以上の結果、本実施の形態の可撓性導体２０を用いることにより、絶縁破壊に対して信頼性が高く、また小寸法化された開閉装置を提供することが可能となる。
【００３７】
実施の形態２．
本発明の実施の形態２による可撓性導体を図に基づいて説明する。図４は実施の形態２による可撓性導体の断面図であり、図１のII−II線に対応する側から見た断面図である。帯状の銅箔１の数十枚が厚さ方向に所定の間隙を有して積層されており、これら銅箔１の間に夫々挟まれる態様で、帯状のステンレス鋼箔２ｃが積層されている。銅箔１，１…は導電帯部１０を形成し、ステンレス鋼箔２ｃ，２ｃ…は絶縁補助帯を形成し、これらが交互に積層されて可撓性導体が構成されている。
【００３８】
銅箔１は無酸素銅で形成されており、長さ150mm ，幅（Ｗ１）50mm及び厚さ0.1mm を有している。ステンレス鋼箔２ｃは銅箔１よりも大きい幅寸法（Ｗ２）を有し、ステンレス鋼箔２ｃの幅方向両端縁２ｅ，２ｅが、銅箔１の幅方向両端縁１ｅ，１ｅよりも両外側に延びて露出している。ステンレス鋼箔２ｃの幅寸法Ｗ２は例えば52mmである。また、ステンレス鋼箔２ｃの長さは銅箔１と同一寸法であり、厚さは銅箔１と同程度の弾性を得る寸法が好ましい。本実施の形態ではスレテンレス合金箔２ｃは厚さ0.1mm である。なお銅箔１の寸法は、通流電流の大きさ、接続する二電路間の距離などにより適宜の値に設定されることが好ましく、上記寸法に限るものではない。またステンレス鋼箔２ｃの幅寸法Ｗ２は、上記に限るものではなく、銅箔１よりも大きい寸法であれば良い。
【００３９】
積層された銅箔１，１…及びステンレス鋼箔２ｃ，２ｃ…は、長さ方向の両端側で除々に間隔を狭めて互いに接触せしめ、箔押さえ材によって固着されている。箔押さえ材の夫々は電路端末の一端に接続されている。箔押さえ材及び電路端末については上述した実施の形態１と同様であり、これらの説明を省略する。また図４に示すように、例えば真空容器の内壁面である接地電位導体９は、可撓性導体の幅方向一端面に対向する位置に配されている。即ち、ステンレス鋼箔２ｃの突出した幅方向端面に対向している。
【００４０】
以上の如き構成の可撓性導体は、真空下で動作する開閉装置の例えば遮断器と他の電路との間に接続される。遮断器の接点開閉時に電路に変位が生じた際に、接続先の電路にその応力を伝達しないように可撓性導体が変位するようになっている。本実施の形態２の可撓性導体は、高電界が発生する箇所である幅方向両端部にステンレス鋼箔２ｃの端縁２ｅを露出せしめてあり、銅箔１の端縁１ｅはステンレス鋼箔２ｃの端縁２ｅにより隠れるので高電界が発生しない。露出しているステンレス鋼箔２ｃの端縁２ｅには高電界が発生するが、上述したように（図３参照）、ステンレス鋼は真空下で銅箔よりも高耐電圧を有している。従って、本実施の形態２の可撓性導体は、銅箔とステンレス鋼箔との幅が等しい従来の可撓性導体よりも耐電圧が上昇し、絶縁破壊が防止される。
【００４１】
なお、図４では、接地電位導体９は銅箔１及びステンレス鋼箔２ｃの幅方向の片側のみに位置しているが、両側に位置する場合もある。また、３相交流回路に使用された場合に接地電位導体９のかわりに他相の充電部が配置されることもある。また、可撓性導体に高電界を発生せしめる接地電位導体９，充電部などが、可撓性導体の片側にしか配置されない場合は、配置されていない側の端部は従来と同様の長さで、即ち、銅箔１とステンレス鋼箔２ｃとが幅方向の端部を揃えて積層してあっても良い。
【００４２】
このように本実施の形態２の可撓性導体は、真空下での耐電圧特性が良好であるので、接地された真空容器に対する地絡放電を防止できる。また３相交流回路に使用された場合に近傍に配置した他相の充電部との間の相間放電を防止できる。以上の結果、本実施の形態２の可撓性導体を用いることにより、絶縁破壊に対して信頼性が高く、また小寸法化された開閉装置を提供することが可能となる。
【００４３】
なお、実施の形態２の可撓性導体は、積層方向の最外層に銅箔１を配した場合を説明しているが、これに限るものではなく、ステンレス鋼箔２ｃと同寸法のものを最外層に配してあっても良い。この場合は、実施の形態１と同様の効果が得られ、耐電圧特性がさらに向上する。
【００４４】
実施の形態３．
本発明の実施の形態３による可撓性導体を図に基づいて説明する。図５は実施の形態３による可撓性導体の断面図であり、図１のII−II線に対応する側から見た断面図である。帯状の銅箔１（導電帯）の数十枚が厚さ方向に所定の間隙を有して積層され、導電帯部が形成されている。銅箔１は無酸素銅で形成されており、長さ150mm ，厚さ0.1mm を有している。銅箔１，１…は、積層方向にその幅寸法を異ならせており、積層方向の両端側の銅箔１の幅Ｗ３は35mmであり、積層方向の中央側の銅箔１の幅Ｗ４は70mmである。即ち、上下端から中央に近づくほど銅箔１の幅寸法が大きくなり、中央で最大幅を有している。導電帯部は断面視で楕円形状を有している。なお銅箔１の寸法は、通流電流の大きさ、接続する二電路間の距離などにより適宜の値に設定されることが好ましく、上記寸法に限るものではない。銅箔１の幅寸法が、積層方向の中央側で最大であれば良い。
【００４５】
積層された銅箔１，１…は、長さ方向の両端側で除々に間隔を狭めて互いに接触せしめ、箔押さえ材によって固着されている。箔押さえ材の夫々は電路端末の一端に接続されている。箔押さえ材及び電路端末については上述した実施の形態１と同様であり、これらの説明を省略する。また図５に示すように、例えば真空容器の内壁面である接地電位導体９は、導電帯の幅方向一端面に対向する位置に配されている。
【００４６】
以上の如き構成の可撓性導体は、真空下で動作する開閉装置の例えば遮断器と他の電路との間に接続される。遮断器の接点開閉時に電路に変位が生じた際に、接続先の電路にその応力を伝達しないように可撓性導体が変位するようになっている。本実施の形態３の可撓性導体は、接地電位導体９からこれに対向する銅箔１の幅方向端面までの距離が、銅箔１の積層方向に異なる。銅箔１の幅方向端面は高電界が発生する箇所である。積層方向の中央側の銅箔１の端部には、従来と同様の高電界が発生するが、接地電位導体９から距離が遠い積層方向両端側の銅箔１では中央側の銅箔１よりも、発生する電界強度が低くなる。即ち、幅が狭い銅箔１ほどその端部に発生する電界強度が低くなり、導電帯全体で発生する電界強度は低くなる。従って、本実施の形態３の可撓性導体は、耐電圧特性が向上し絶縁破壊が防止される。
【００４７】
なお、図５では、接地電位導体９は銅箔１の幅方向の片側のみに位置しているが、両側に位置する場合もある。また、３相交流回路に使用された場合に接地電位導体９のかわりに他相の充電部が配置されることもある。また、可撓性導体に高電界を発生せしめる接地電位導体９，充電部などが、可撓性導体の片側にしか配置されない場合は、配置されていない側の端部は従来と同様の長さで、即ち、端部を揃えて積層してあっても良い。
【００４８】
このように本実施の形態３の可撓性導体は、真空下での耐電圧特性が良好であるので、接地された真空容器に対する地絡放電を防止できる。また３相交流回路に使用された場合に近傍に配置した他相の充電部との間の相間放電を防止できる。以上の結果、本実施の形態３の可撓性導体を用いることにより、絶縁破壊に対して信頼性が高く、また小寸法化された開閉装置を提供することが可能となる。
【００４９】
なお、実施の形態３の可撓性導体は、導電帯として銅箔のみを用いた場合を説明しているが、これに限るものではなく、積層方向の最外層のみに上述した幅Ｗ３のステンレス鋼箔を配してあっても良い。この場合は、実施の形態１と同様の効果が得られ、耐電圧特性がさらに向上する。
【００５０】
実施の形態４．
本発明の実施の形態４による可撓性導体を図に基づいて説明する。図６は実施の形態４による可撓性導体の断面図であり、図１のII−II線に対応する側から見た断面図である。銅箔１，１…は、積層方向にその幅寸法を異ならせて34枚が積層されている。積層方向の両端側の銅箔１の幅Ｗ５は35mmであり、積層方向の中央側の14枚の銅箔１は幅Ｗ６が70mmである。実施の形態４では、上下端から中央に近づくほど銅箔１の幅寸法が大きくなり、中央の14枚の銅箔１，１…が最大幅を有している。その他の構成は、実施の形態３と同様であり、その説明を省略する。なお銅箔１の寸法は、通流電流の大きさ、接続する二電路間の距離などにより適宜の値に設定されることが好ましく、上記寸法に限るものではない。積層方向の中央側で複数の銅箔１の幅寸法が最大であれば良い。
【００５１】
以上の如き構成の可撓性導体は、真空下で動作する開閉装置の例えば遮断器と他の電路との間に接続される。遮断器の接点開閉時に電路に変位が生じた際に、接続先の電路にその応力を伝達しないように可撓性導体が変位するようになっている。本実施の形態４の可撓性導体は、実施の形態３と同様に、幅が狭い銅箔１ほどその端部に発生する電界強度が低くなり、帯電圧特性が向上し、絶縁破壊が防止される。また、積層方向中央側に、最大幅である同寸法の銅箔１を複数積層してあるので、本実施の形態４の可撓性導体は、開閉装置の通電電流に応じて最大幅の銅箔の枚数を調整することにより、通電容量が異なる複数の開閉装置に共通で使用することができる。
【００５２】
なお、図６では、接地電位導体９は銅箔１の幅方向の片側のみに位置しているが、両側に位置する場合もある。また、３相交流回路に使用された場合に接地電位導体９のかわりに他相の充電部が配置されることもある。また、可撓性導体に高電界を発生せしめる接地電位導体９，充電部などが、可撓性導体の片側にしか配置されない場合は、配置されていない側の端部は従来と同様の長さで、即ち、端部を揃えて積層してあっても良い。
【００５３】
このように本実施の形態４の可撓性導体は、真空下での耐電圧特性が良好であるので、接地された真空容器に対する地絡放電を防止できる。また３相交流回路に使用された場合に近傍に配置した他相の充電部との間の相間放電を防止できる。以上の結果、本実施の形態４の可撓性導体を用いることにより、絶縁破壊に対して信頼性が高く、また小寸法化された開閉装置を提供することが可能となる。
【００５４】
なお、実施の形態４の可撓性導体は、導電帯として銅箔のみを用いた場合を説明しているが、これに限るものではなく、積層方向の最外層のみに上述した幅Ｗ５のステンレス鋼箔を配してあっても良い。この場合は、実施の形態１と同様の効果が得られ、耐電圧特性がさらに向上する。
【００５５】
実施の形態５．
本発明の実施の形態５による可撓性接続部材を図に基づいて説明する。図７は実施の形態５による可撓性接続部材の斜視図である。図７に示すように、帯状の銅箔１の数十枚が厚さ方向に0.2mm の間隙を有して積層された導電帯部１０と、導電帯部１０の積層方向両外側に配されたステンレス鋼箔２ａ，２ｂ（絶縁補助帯）とで可撓性導体２０が形成されている。可撓性導体２０は、長さ方向の両端側で除々に間隔を狭めて互いに接触せしめ、箔押さえ材３によって固着されている。箔押さえ材の夫々は図示しない電路端末の一端に接続されている。なお、可撓性導体２０は、上述した実施の形態１と同様であり、銅箔１及びステンレス鋼箔２ａ，２ｂの材質，寸法及びその構成について省略する。
【００５６】
可撓性導体２０の外周には、線状又は細板状のステンレス鋼で形成された螺旋シールド５が、所定の螺旋間隔及び螺旋径で巻回されている。本実施の形態では、螺旋シールド５の線径は1.5 mmであり、螺旋間隔が５mm、螺旋径は螺旋シールド５が可撓性導体２０から外周側に５mm離隔する寸法である。螺旋シールド５の一端５ａは、螺旋シールド押さえ材６により箔押さえ材３に固定されており、他端５ｂは自由端になっている。なお、螺旋シールド５は導体で形成してあれば良く、真空下での耐電圧特性が良好なステンレス鋼が好ましい。また、螺旋シールド５の寸法及び螺旋間隔などは上述の寸法に限らず、電界緩和効果が発揮される寸法であれば良い。この寸法は、銅箔１の長さに対して電界計算を行なって結果が得られると推測される線径，螺旋間隔及び螺旋径の範囲を絞り、次に候補形状により実験を行ない、その結果に基づいて決定される。
【００５７】
以上の如き構成の可撓性接続部材は、真空下で動作する開閉装置の例えば遮断器と他の電路との間に接続される。遮断器の接点開閉時に電路に変位が生じた際に、接続先の電路にその応力を伝達しないように可撓性接続部材が変位するようになっている。螺旋シールド５を可撓性導体２０と同電位で接続したこの可撓性接続部材に100 kVの電圧を印加し、螺旋シールド５の表面の電界強度を測定した。図８はその結果を示す棒グラフであり、縦軸は可撓性接続部材の表面の電界強度を示している。比較のために、螺旋シールドを配していない従来の可撓性接続部材の幅方向端縁部の電界強度を測定し、同様に示している。なお、接地電位導体９が銅箔１の幅方向一端面に対向する位置に配されており、螺旋シールド５と接地電位導体９との間の距離は20mmである。比較例では銅箔と接地電位導体９との間の距離は25mmである。
【００５８】
グラフから、本実施の形態５の可撓性接続部材は表面電界は10.2kV/mm であった。一方、螺旋シールドを配していない比較例では、可撓性接続部材の表面と接地電位導体９との距離が本実施の形態よりも５mm長いにも関わらず 35kV/mmであった。以上の結果から本実施の形態５の可撓性接続部材は、螺旋シールド５により表面の電界強度が低減されて電界緩和効果が得られる。これは、可撓性接続部材の最外層となる螺旋シールド５の曲率が帯状導体よりも大きいこと、及び、螺旋シールド５の巻回された隣合う線状導体の相互作用によると考えられる。
【００５９】
このように本実施の形態５の可撓性接続部材は電界緩和効果が得られるので、接地された真空容器に対する地絡放電を防止できる。また３相交流回路に使用された場合に近傍に配置した他相の充電部との間の相間放電を防止できる。以上の結果、本実施の形態５の可撓性接続部材を用いることにより、絶縁破壊に対して信頼性が高く、また小寸法化された開閉装置を提供することが可能となる。また螺旋シールド５自体にも可撓性があるので、可撓性接続部材の変位にも柔軟に変位することができる。
【００６０】
なお、実施の形態５の可撓性接続部材は、実施の形態１の構造の可撓性導体に螺旋シールド５を巻回した場合を説明しているが、これに限るものではなく、実施の形態２〜４に示した夫々の可撓性導体の外周に螺旋シールド５を巻回してあっても良い。これらの場合は、耐電圧特性がさらに向上する。
【００６１】
実施の形態６．
本発明の実施の形態６による可撓性接続部材を図に基づいて説明する。図９は実施の形態６による可撓性接続部材の側面図であり、図１０は図９のＸ−Ｘ線から見た断面図である。帯状の銅箔１（導電帯）の数十枚が厚さ方向に所定の間隙を有して積層され、可撓性導体が形成されている。銅箔１は無酸素銅で形成されており、長さ150mm ，幅50mm，厚さ0.1mm である。銅箔１の寸法は、通流電流の大きさ、接続する二電路間の距離などにより適宜の値に設定されることが好ましく、上記寸法に限るものではない。積層された銅箔１，１…は、長さ方向の両端側で除々に間隔を狭めて互いに接触せしめ、箔押さえ材によって固着されている。箔押さえ材の夫々は電路端末の一端に接続されている。箔押さえ材及び電路端末については上述した実施の形態１と同様であり、これらの説明を省略する。
【００６２】
可撓性導体の長さ方向両端部の外周には、ステンレス鋼製のカバー導体（電界緩和シールド部）７，７が配されており、両カバー導体７，７間は20mm〜40mmの間隔を有している。各カバー導体７は銅箔１，１…の幅方向両端面に夫々対向配置された２枚のカバー導体片７１，７２で構成されており、カバー導体片７１，７２は銅箔１，１…の幅方向両端面に夫々接触している。また各カバー導体片７１，７２は銅箔１の対向部分が平板で、上下端７ａ，７ｂが任意の曲率で内側に湾曲した形状に形成されている。この上下端７ａ，７ｂは、銅箔１の積層表面に生じる高電界を緩和する効果を有する。カバー導体片７１，７２の厚さは、湾曲部のプレス加工の容易さを考慮して本実施例では1mm に形成されている。各カバー導体７は、一端を箔押さえ材３にろう付け接合され、他端は自由端になっている。これにより、可撓性導体の変位に対応できる。
【００６３】
なお、カバー導体７の材質は真空下での耐電圧特性が良好なステンレス鋼が好ましいが、導体であればその他の材料で形成してあっても良い。また、カバー導体７，７の両者が対向する側は湾曲に形成してあっても良いし、湾曲してなくても良い。さらに、カバー導体７は上下端７ａ，７ｂが湾曲していない平板状であっても良い。さらにまた、上述した如く（図１０）、例えば真空容器の内壁面のような２つの接地電位導体９１，９２が可撓性導体の幅方向両端面に対向する位置に配されている場合は、接地電位導体９１，９２の夫々にカバー導体片７１，７２を対向配置することが好ましい。図示しないが、接地電位導体９１のかわりに可撓性接続部材の端部が配置されることもある。このように周囲に配置される部材の状況により、カバー導体片は片側のみに設置しても良い。
【００６４】
以上の如き構成の可撓性接続部材は、真空下で動作する開閉装置の例えば遮断器と他の電路との間に接続される。遮断器の接点開閉時に電路に変位が生じた際に、接続先の電路にその応力を伝達しないように可撓性接続部材が変位するようになっている。本実施の形態６の可撓性接続部材は、高電界が発生する銅箔１の幅方向端面を導体で覆っているので電界緩和効果が得られる。以下に、本実施の形態の可撓性接続部材の破壊電圧について調べた結果を示す。
【００６５】
図１１は、可撓性接続部材の破壊電圧の測定結果を示すグラフである。縦軸は破壊電圧を示し、横軸はカバー導体片と接地電位導体との距離を示している。この破壊電圧は、可撓性接続部材のカバー導体と極めて大きい平板状の接地導体とを対向するように配置し、その距離を変化させて10^-6Torrの高真空中で測定した。グラフ中、‘○’は、本実施の形態のカバー導体の両者間距離が20mmの破壊電圧、‘□’は同じくカバー導体の両者間距離が40mmの破壊電圧、‘×’はカバー導体を配していない従来例の破壊電圧を示している。グラフから判るように、カバー導体を配さない従来例と比較して本実施の形態６の可撓性接続部材は破壊電圧が高い。例えばカバー導体間距離が40mmのものは、カバー導体片と接地電位導体との距離が同一のとき、破壊電圧は従来の略２倍である。カバー導体間距離が20mmのものは略３倍である。従って、本実施の形態６はカバー導体７の設置により、可撓性接続部材の長さ方向端部の外周全てをカバー導体で覆わなくても耐電圧特性が向上する。よって、耐電圧特性が向上し絶縁破壊が防止される。
【００６６】
このように本実施の形態６の可撓性接続部材は、真空下での耐電圧特性が良好であるので、接地された真空容器に対する地絡放電を防止できる。また３相交流回路に使用された場合には、近傍に配置した他相の充電部との間の相間放電を防止できる。以上の結果、本実施の形態６の可撓性接続部材を用いることにより、絶縁破壊に対して信頼性が高く、また小寸法化された開閉装置を提供することが可能となる。
【００６７】
なお、カバー導体片７１，７２は銅箔１の端面に必ずしも接触していなくても良く、非接触で任意の間隙を有していても良い。カバー導体片７１，７２と銅箔１との間隔を4.7mm とし、カバー導体７と平板状の接地電位導体との距離を7.7mm 、カバー導体７，７間の距離を20mmとした場合の破壊電圧は260kV である。すなわちカバー導体７と銅箔１との間に距離を設けても耐電圧特性はカバー導体７のない場合よりも向上する。
【００６８】
実施の形態７．
上述した実施の形態６の可撓性接続部材は、銅箔１のみの積層構造の可撓性導体にカバー導体７を配した場合を説明しているが、これに限るものではなく、実施の形態１〜４に示した夫々の可撓性導体の端面にカバー導体７を配してあっても良い。これらの場合は、耐電圧特性がさらに向上する。図１２は、実施の形態３で示した可撓性導体にカバー導体を配した可撓性接続部材の断面図である。図に示すように、可撓性導体は積層方向の両端部は幅が狭く、中央ほど幅が広い銅箔１，１…で形成されており、この可撓性導体の幅方向端面に対向するようにカバー導体７が非接触で配されている。カバー導体７の両外側には、接地電位導体９１，９２が夫々、対向配置されている。カバー導体７は、実施の形態６と同様の材料及び形状のカバー導体片７１，７２で構成されており、その説明を省略する。このように実施の形態７は、耐電圧特性が良好な可撓性導体に、幅方向の端面を覆うようにカバー導体７を配してあるので、耐電圧特性がさらに向上する。
【００６９】
以上の如く、実施の形態６，７では、カバー導体７，７を配することにより可撓性接続部材の耐電圧特性が向上し、絶縁破壊に対する信頼性が向上する。またこの向上分だけ絶縁距離を短くすることにより、同等の信頼性を保ったまま可撓性接続部材の小寸法化が図られる。
【００７０】
実施の形態８．
図１３は実施の形態８による可撓性接続部材の側面図であり、図１４は図１３の XIV−XIV 線から見た断面図である。帯状の銅箔１（導電帯）の数十枚が厚さ方向に所定の間隙を有して積層され、可撓性導体が形成されている。銅箔１は無酸素銅で形成されており、長さ150mm ，幅50mm，厚さ0.1mm である。銅箔１の寸法は、通流電流の大きさ、接続する二電路間の距離などにより適宜の値に設定されることが好ましく、上記寸法に限るものではない。積層された銅箔１，１…は、長さ方向の両端側で除々に間隔を狭めて互いに接触せしめ、箔押さえ材によって固着されている。箔押さえ材の夫々は電路端末の一端に接続されている。箔押さえ材及び電路端末については上述した実施の形態１と同様であり、これらの説明を省略する。
【００７１】
可撓性導体の外周には、アルミナ又は耐熱ガラスで形成された絶縁カバー（絶縁部）８が配されている。絶縁カバー８は、銅箔１，１…の幅方向両端面に夫々対向配置された平板状の絶縁カバー片８１，８２で構成されており、絶縁カバー片８１，８２は銅箔１，１…の幅方向両端面と非接触である。絶縁カバー片８１，８２の厚さは、絶縁材料の強度が得られる程度が好ましい。絶縁カバー８は、導電帯の端縁側を長さ方向の全域にわたって覆っており、その一端が箔押さえ材３のどちらか一方にろう付け接合され、他端は自由端になっている。これにより、可撓性導体の変位に対応できる。絶縁カバー８の材質はアルミナ、耐熱ガラスなどの真空絶縁材料が好ましい。
【００７２】
以上の如き構成の可撓性接続部材は、真空下で動作する開閉装置の例えば遮断器と他の電路との間に接続される。遮断器の接点開閉時に電路に変位が生じた際に、接続先の電路にその応力を伝達しないように可撓性接続部材が変位するようになっている。本実施の形態８の可撓性接続部材は、高電界が発生する銅箔１の幅方向端面を絶縁物で覆っているので、可撓性接続部材の端面のような高電界部から放出された電界放出電子は絶縁物によって遮蔽され、相手側導体へ移動できなくなる。真空放電では、陰極側の高電界部から電界電子が生じ、その放出電子が陽極へ加速されながら移動し、衝突することが放電の引き金のひとつと考えられている。従って、絶縁物によって電界放出電子の移動を妨げることにより、破壊電圧が上昇する。
【００７３】
なお、上述した如く（図１４参照）、例えば真空容器の内壁面のような２つの接地電位導体９１，９２が可撓性導体の幅方向両端面に対向する位置に配されている場合は、接地電位導体９１，９２の夫々に絶縁カバー片８１，８２を対向配置することが好ましい。図示しないが、接地電位導体９１のかわりに可撓性接続部材の端部が配置されることもある。このように周囲に配置される部材の状況により、絶縁カバー片は片側のみに設置しても良い。また、絶縁カバー８は、上下端の夫々が内側に湾曲した形状であっても良い。
【００７４】
このように絶縁カバー８を配することによって真空下での耐電圧特性が向上する。この向上分だけ絶縁距離を短くした場合は、同等の信頼性を保ったまま可撓性接続部材の小寸法化を図ることができる。また、絶縁距離を従来と同様にして絶縁カバー８を配した場合は、絶縁破壊に対する信頼性が向上する。
【００７５】
実施の形態９．
上述した実施の形態８の可撓性接続部材は、銅箔１のみの積層構造の可撓性導体に絶縁カバー８を配した場合を説明しているが、これに限るものではなく、実施の形態１〜４に示した夫々の可撓性導体に絶縁カバー８を配してあっても良い。これらの場合は、耐電圧特性がさらに向上する。図１５は、実施の形態４で示した可撓性導体に絶縁カバーを配した可撓性接続部材の断面図である。図に示すように、可撓性導体は積層方向の両端部は幅が狭く、中央ほど幅が広い銅箔１，１…で形成されており、この可撓性導体の幅方向端面に対向するように絶縁カバー８が非接触で配されている。絶縁カバー８は、実施の形態８と同様の材料及び形状の絶縁カバー片８１，８２で構成されており、その説明を省略する。このように、耐電圧が高い構造の可撓性導体に、幅方向の端面を覆うように絶縁カバー８を配してあるので、耐電圧特性がさらに向上する。
【００７６】
【発明の効果】
以上のように、第１〜第３発明に係る可撓性導体によれば、導電帯部の積層方向の両外側で露出する絶縁補助帯、又は導電帯部と交互に積層されて幅方向の端縁側で露出する絶縁補助帯を備えるので、可撓性導体の真空下での耐電圧特性が向上し、絶縁破壊が防止される。
【００７７】
第４〜第６発明に係る可撓性導体によれば、導電帯部は積層方向の中央側に最も広い幅寸法の導電帯を配しているので、幅方向端部に発生する電界強度は、中央側が従来と同程度、積層方向両端側では低減する。これにより、電界緩和効果を得、絶縁破壊が防止される。
【００７８】
第７発明に係る可撓性接続部材によれば、上述したような耐電圧特性が向上する可撓性導体又は絶縁破壊が防止される可撓性導体の外周に導体を螺旋状に巻回してあるので、可撓性導体に発生する表面の電界強度をさらに低減できる。
【００７９】
第８又は第９発明に係る可撓性接続部材によれば、導電帯の幅方向の端面を電界緩和シールド部で覆っているので、可撓性接続部材の耐電圧が高まり、絶縁破壊を防止できる。また、上述したような耐電圧特性が向上する可撓性導体又は絶縁破壊が防止される可撓性導体の幅方向の端面を電界緩和シールド部で覆っているので、耐電圧がさらに高まる。
【００８０】
第１０発明に係る可撓性接続部材によれば、電界緩和シールド部は導体製であるので、可撓性導体の電界強度が低減し、絶縁破壊を防止できる。
【００８１】
第１１発明に係る可撓性接続部材によれば、導電帯の幅方向の端面を絶縁部で覆っているので、端面から放出された電界放出電子が絶縁部で遮蔽され、真空放電を防止できる等、本発明は優れた効果を奏する。
【００８２】
【図面の簡単な説明】
【図１】実施の形態１の可撓性導体の構造を示す斜視図である。
【図２】図１のII−II線から見た断面図ある。
【図３】実施の形態１の可撓性導体の効果を説明するグラフである。
【図４】実施の形態２の可撓性導体の構造を示す断面図である。
【図５】実施の形態３の可撓性導体の構造を示す断面図である。
【図６】実施の形態４の可撓性導体の構造を示す断面図である。
【図７】実施の形態５の可撓性接続部材の構造を示す斜視図である。
【図８】実施の形態５の可撓性接続部材の効果を説明するグラフである。
【図９】実施の形態６の可撓性接続部材の構造を示す側面図である。
【図１０】図９のＸ−Ｘ線から見た断面図ある。
【図１１】実施の形態６の可撓性接続部材の効果を説明するグラフである。
【図１２】実施の形態７の可撓性接続部材の構造を示す断面図である。
【図１３】実施の形態８の可撓性接続部材の構造を示す側面図である。
【図１４】図１３のXIV −XIV 線から見た断面図である。
【図１５】実施の形態９の可撓性接続部材の構造を示す断面図である。
【図１６】従来の可撓性導体の構造を示す部分断面図である。
【符号の説明】
１銅箔、１ｅ銅箔の幅方向端縁、２ａ，２ｂ，２ｃステンレス鋼箔、
２ｅステンレス鋼箔の幅方向端縁、３箔押さえ材、４電路端末、５螺旋シールド、６螺旋シールド押さえ材、７カバー導体、８絶縁カバー、９接地電位導体、１０導電帯部、１１集合導体、２０可撓性導体、
７１，７２カバー導体片、８１，８２絶縁カバー片、９１，９２接地電位導体。[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a flexible conductor and a flexible connecting member that electrically connect two electric circuits loaded with a high voltage and large current and absorb the stress caused by the displacement of each electric circuit, and particularly used under high vacuum. The present invention relates to a flexible conductor in which strip-shaped conductors are laminated and a flexible connecting member.
[0002]
[Prior art]
A switchgear widely used as a power receiving / transforming facility has a configuration in which element devices such as a circuit breaker, a disconnecting switch, and a grounding switch are accommodated inside a grounding container. Some of the component devices cause displacement in the electric circuit, for example, opening and closing of a circuit breaker contact. A flexible conductor is used for connection between the circuit breaker and the other electric circuit. This is because unnecessary stress and impact force due to the displacement of the movable-side electrode of the circuit breaker are not transmitted to other connected electric paths. In addition, the flexible conductor does not transmit thermal stress and vibration due to temperature changes, and distortion stress due to mounting errors to other electrical circuits, not only due to external mechanical forces such as opening and closing of contacts as described above. May also be used.
[0003]
As the material used for the flexible conductor, since the switchgear conducts a large current, copper having a low resistivity is generally used. In order to make this copper exhibit flexibility, a copper bundle that is bundled in a thin wire or a foil that is laminated in a foil shape is used. In the case of the former, the individual linear conductors or foil-like conductors constituting the flexible conductor may cause the strands to be scattered, jumped out or disconnected in the former case, and in the latter case, the foil may be unevenly bent. Arise. Since the switchgear operates at a high voltage, a high electric field is generated at the tip portion or sharp portion of the portion where such non-uniformity occurs. Moreover, even if there is no change in shape due to long-term use, the edges, edges, etc. of the foil-like conductor are easy to generate a high electric field, which is the high electric field part of such a high-voltage charging part and the ground potential. There is a risk that a ground fault discharge will occur between the container wall surface. In the case of a three-phase AC type switchgear, there is a risk that correlated discharge may occur in a high electric field part between different-phase charging parts. Further, when the inside of the container is an insulating gas atmosphere, partial discharge occurs even if dielectric breakdown does not occur, and the insulating performance gradually decreases due to generation of impurity gas.
[0004]
In order to solve this, Japanese Patent Laid-Open No. 1-255410 has been proposed as a prior example in which a high electric field portion is not generated in a non-uniform portion of a flexible conductor. FIG. 16 is a partial cross-sectional view showing the structure of the flexible conductor. The connection conductor 100 is electrically connected between the two electric circuits by the collective conductor 11 formed of a thin conductor wire, and both ends 12 and 13 of the connection conductor 100 are tightly bundled and connected to the other electric circuit terminals 16 and 17, respectively. It is connected. The outer periphery of the collective conductor 11 is covered with shield members 21 and 22 made of cylindrical conductors having smooth outer surfaces over the substantially entire length of the collective conductor 11 with an appropriate interval from the collective conductor 11. These members are all installed in an insulating gas atmosphere.
[0005]
In addition, a flexible conductor having a structure in which an insulator is interposed between the shield members 21 and 22 and the collective conductor 11 has been proposed (Japanese Unexamined Patent Publication No. Hei 1-86429). In the connection conductor 100 used in such an insulating gas atmosphere, even when individual thin wires constituting the assembly conductor 11 are scattered or protruded, the shield members 21 and 22 do not generate a high electric field on the conductor thin wires themselves. Therefore, the occurrence of dielectric breakdown and partial discharge can be suppressed.
[0006]
[Problems to be solved by the invention]
The effect of the shield member made of conductor as described above will be described in detail as follows. When a grounding conductor is placed in the vicinity of the flexible conductor in the insulating gas and there is no shield member between them, a high electric field is generated at the end of the flexible conductor, and the electric field distribution is unequal. It becomes an electric field. And when a shield member is interposed between both, the edge part of a flexible conductor is covered with a shield member, and an electric field distribution will be in the state close | similar to an equal electric field. science fiction ₆ In the case of the gas insulating medium represented by the above, high insulation performance is exhibited under an equal electric field distribution, but the insulation performance as under an equal electric field distribution does not appear under an uneven electric field distribution. Therefore, it can be seen that the excellent characteristics of gas insulation are brought out by the installation of the shield member, and dielectric breakdown and partial discharge can be prevented.
[0007]
On the other hand, pressure 10 ^-6 A high vacuum of about Torr may be used. In general, the breakdown characteristics in high vacuum are different from those in gas in the following points. When an equal electric field is formed by arranging the shield member having the above-described structure, the area of the portion that takes a value of, for example, 90% of the maximum electric field on the surface of the shield member is a flexible conductor when no shield member is provided. It is much larger than the area of the portion taking up to 90% of the maximum electric field on the surface. An increase in the area of a portion having an electric field substantially equal to the maximum electric field means an increase in the number of weak point factors that are the starting points that cause dielectric breakdown. In gas, the breakdown characteristics, that is, the breakdown voltage is improved as a result of not forming an unequal electric field even when the number of weak point factors is increased. On the other hand, in a high vacuum, a good dielectric breakdown voltage can be maintained even if the electric field is not as uniform as in a gas. In other words, the dielectric breakdown voltage may be higher when the unequal electric field is not increased without increasing the number of weakness factors.
[0008]
As described above, since the level of the equal electric field or the degree of influence of the electrode area on the breakdown voltage is different between the high vacuum and the gas, the above-mentioned preceding example intended to be applied to a gas insulating device is a vacuum. There was a problem that the same effect could not be exhibited for the insulation equipment.
[0009]
The present invention has been made in view of such circumstances, and in order to prevent dielectric breakdown of a flexible conductor or a flexible connecting member used under high vacuum, an auxiliary insulation band, a spiral conductor, an electric field relaxation are provided. Flexible conductors that can provide shields or insulating parts in place, and as a result, improve the withstand voltage under high vacuum, prevent vacuum discharge, and realize the downsizing and reliability of equipment An object is to provide a flexible connecting member.
[0010]
[Means for Solving the Problems]
The flexible conductor according to the first aspect of the present invention includes a plurality of conductive bands stacked, a conductive band that electrically connects two electrical paths, and both the outer sides of the conductive band in the stacking direction. An insulation auxiliary band having substantially the same degree of elasticity as the band is provided.
[0011]
A flexible conductor according to a second aspect of the present invention includes a conductive band portion in which a plurality of conductive bands are laminated, electrically connecting two electric paths, a width dimension wider than the conductive band, and an edge in the width direction Are provided with auxiliary insulation bands arranged between the conductive bands so as to protrude from the conductive bands.
[0012]
The flexible conductor according to a third invention is characterized in that, in the first or second invention, the conductive band is made of copper and the auxiliary insulation band is made of stainless steel.
[0013]
The flexible conductor according to the fourth aspect of the present invention includes a conductive band portion in which a plurality of conductive bands for electrically connecting two electric paths are stacked, and the conductive band portions are arranged at both ends on the center side in the stacking direction. The conductive band having a wider width is provided.
[0014]
The flexible conductor according to a fifth aspect of the present invention is characterized in that, in the fourth aspect, the conductive band portion has a width dimension of the conductive band that is increased from both end sides to the central side in the stacking direction.
[0015]
A flexible conductor according to a sixth invention is characterized in that, in the fourth invention, the conductive band portion is provided with a plurality of conductive bands having the widest width dimension on the center side in the stacking direction.
[0016]
A flexible connecting member according to a seventh aspect of the present invention is a flexible conductor according to any one of the first to sixth aspects of the invention, and is wound spirally around the outer circumference of the flexible conductor, one end of which is the flexible It is electrically connected to the edge part of a conductor, and the other end is provided with the helical conductor which is a free end, It is characterized by the above-mentioned.
[0017]
A flexible connecting member according to an eighth aspect of the present invention covers a flexible conductor formed by laminating a plurality of conductive bands for electrically connecting two electric paths, and a width direction end face of the conductive band, and is laminated in the direction of lamination. And an electric field relaxation shield that exposes the conductive band on the end face.
[0018]
A flexible connecting member according to a ninth aspect of the invention covers the flexible conductor according to any one of the first to sixth aspects of the invention and the electric field that covers the widthwise end face of the conductive band and exposes the conductive band of the end face in the stacking direction. And a relaxation shield part.
[0019]
In the flexible connecting member according to a tenth aspect of the present invention, in the eighth or ninth aspect, the electric field relaxation shield portions are respectively disposed on both ends in the longitudinal direction of the conductive band, and each electric field relaxation shield portion has a width of the conductive band. It is a conductive plate disposed opposite to both end faces in the direction.
[0020]
A flexible connecting member according to an eleventh aspect of the present invention is a flexible conductor formed by laminating a plurality of conductive bands for electrically connecting two electric paths, and an oppositely disposed end face in the width direction of the conductive band. And an insulated part.
[0021]
In the flexible conductor according to the first aspect of the present invention, for example, by arranging an auxiliary insulation band made of stainless steel on both outer sides in the stacking direction of the conductive band portion in which conductive bands such as copper foil are stacked, flexibility is achieved. The voltage which can maintain the insulation between a conductor and a different potential member (for example, a container wall surface, a different phase high voltage | pressure charging part etc.) can be made high. This is because, as shown in FIG. 3, the breakdown voltage between two electrodes placed in a high vacuum is higher when the electrode is made of stainless steel than when it is made of copper.
[0022]
In a flexible conductor formed by stacking conductive bands, a high electric field is generated on both outer surfaces in the stacking direction where bending occurs and at the edges of the conductive bands. In the first aspect of the invention, by providing the auxiliary insulation band in the portion with high electric field strength, the withstand voltage characteristic of the flexible conductor is improved, and the dielectric breakdown of the flexible conductor is prevented. Moreover, by making the elasticity of the insulating auxiliary band approximately the same as that of the conductive band, the insulating auxiliary band does not hinder the displacement of the conductive band, and the insulating auxiliary band does not move away from the conductive band. As a result, the occurrence of dielectric breakdown in the flexible conductor can be prevented, the size of the device can be reduced, and high reliability can be obtained. The auxiliary insulation band is not limited to stainless steel, but may be any conductor that has a higher withstand voltage under vacuum than the conductive band and has flexibility.
[0023]
In the second invention, by making the width of the insulation auxiliary band larger than that of the conductive band, the edge in the width direction of the insulation auxiliary band is exposed, and the edge of the conductive band is inside the edge of the auxiliary insulation band. Located at, and not exposed. Therefore, a high electric field is not generated at the edge of the conductive band, and a high electric field is generated only at the edge of the auxiliary insulation band. Therefore, the auxiliary insulation band is arranged more than the conventional flexible conductor having the same width. The withstand voltage characteristic under vacuum is improved as compared with a flexible conductor that does not.
[0024]
In the third invention, the conductive band is made of copper and the auxiliary insulation band is made of stainless steel. As described above, since stainless steel has a higher withstand voltage under vacuum than copper, a flexible conductor having high insulation can be obtained even when a high electric field is generated.
[0025]
In the fourth or fifth invention, since the plurality of conductive bands are laminated so that the central portion in the laminating direction is wider, the conductive bands on both outer sides in the laminating direction are from the ground potential conductor than the central portion. And the electric field strength is lower than that at the center. This improves the withstand voltage characteristics of the conductive band under vacuum and prevents electric field breakdown.
[0026]
In the sixth invention, similarly to the above, the electric field strength of the conductive bands on both outer sides in the stacking direction is lowered, and dielectric breakdown is prevented. Furthermore, since the width of the plurality of conductive bands in the central portion is constant, by adjusting the number of conductive bands having a constant width, it can be used in common for flexible conductors having different magnitudes of current that can be energized.
[0027]
In the flexible connecting member according to the seventh aspect of the present invention, a flexible conductor having a structure in which the withstand voltage characteristics as described in the first to sixth aspects of the invention are improved, or a structure in which the electric field strength of the surface can be reduced, Since the linear or belt-like conductor is wound spirally, the electric field strength of the surface generated in the flexible conductor can be reduced. Moreover, since the spiral conductor is wound in a spiral shape, it can follow the displacement of the flexible conductor.
[0028]
Of the entire surface of the flexible conductor, the electric field strength increases at the end of the conductive band. In the eighth invention, the end face in the width direction of the conductive band is covered with the electric field relaxation shield portion, thereby increasing the withstand voltage of the flexible connecting member under vacuum and preventing dielectric breakdown. In the ninth invention, the width direction of the conductive band is applied to a flexible conductor having a structure with improved withstand voltage characteristics as described in the first to sixth inventions or a structure capable of reducing the electric field strength of the surface. Since the electric field relaxation shield covering the end face is arranged, the withstand voltage characteristic of the flexible connecting member is further improved.
[0029]
In the tenth invention, since the electric field relaxation shield part is made of a conductor, a high electric field is generated in the electric field relaxation shield part and the electric field strength of the flexible conductor is reduced, so that dielectric breakdown is prevented.
[0030]
When discharge occurs from the end face in the width direction of the conductive band of the flexible connecting member, the electric field intensity at this end face becomes very high, field emission occurs, and the electrons move to the other conductor while being accelerated. It is considered to be a trigger for. In the eleventh aspect of the invention, since the edge portion of the conductive band is covered with the insulating portion, the field emission electrons emitted from the edge portion are shielded by the insulating portion and cannot move to the counterpart conductor. This prevents vacuum discharge.
[0031]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the present invention will be specifically described with reference to the drawings showing embodiments thereof.
Embodiment 1 FIG.
A flexible conductor according to Embodiment 1 of the present invention will be described with reference to the drawings. 1 is a perspective view of a flexible conductor 20 according to Embodiment 1, and FIG. 2 is a cross-sectional view taken along line II-II in FIG. As shown in FIG. 1, the conductive band portion 10 is formed by laminating several tens of strip-shaped copper foils 1 with a predetermined gap in the thickness direction. The copper foil 1 is made of oxygen-free copper and has a length of 150 mm, a width of W50 mm, and a thickness of 0.1 mm. Stainless steel foils 2a and 2b (insulation auxiliary bands) are laminated on both outer sides of the conductive band portion 10 in the laminating direction, that is, on the upper and lower sides of the copper foils 1, 1. The stainless steel foils 2 a and 2 b have the same length and width as the copper foil 1. Further, the thickness of the stainless steel foils 2a and 2b is formed so as to obtain the same degree of elasticity as that of the copper foil 1, for example, 0.1 mm in this embodiment. As shown in FIG. 2, the copper foil 1 and the stainless steel foils 2a and 2b are laminated with the end faces in the width direction aligned. In addition, it is preferable that the dimension of the copper foil 1 is set to an appropriate value depending on the magnitude of the flowing current, the distance between the two electric circuits to be connected, and the like, and is not limited to the above dimensions.
[0032]
The laminated copper foils 1, 1... And the stainless steel foils 2 a and 2 b are brought into close contact with each other at the both ends in the length direction, and are fixed by the foil pressing members 3 and 3. The foil retainer 3 is made of copper having a low resistivity because the flexible conductor 20 is a current conducting member. The fixing method of the foil pressing member 3 includes fixing by caulking, screw tightening or bolt tightening, but a method of fixing by brazing is preferable when used in a high vacuum. This brazing may be performed simultaneously with the brazing process of other members (not shown).
[0033]
Each of the foil pressing members 3 is connected to one end of the electric circuit terminals 4 and 4. The electric circuit terminal 4 is a part of another electric circuit (not shown). For example, a circuit breaker or a disconnector is connected to the other end of the electric circuit terminal 4. As shown in FIG. 2, the ground potential conductor 9 is disposed at a position facing the end faces in the width direction of the copper foil 1 and the stainless steel foils 2a and 2b. The ground potential conductor 9 is, for example, the inner wall surface of the vacuum vessel, and is omitted in FIG. 1 for the sake of complexity. In FIG. 2, the ground potential conductor 9 is located only on one side in the width direction of the copper foil 1 and the stainless steel foils 2a and 2b, but may be located on both sides. Further, an end portion of another flexible conductor may be arranged instead of the ground potential conductor 9.
[0034]
The flexible conductor 20 having the above-described configuration is connected between, for example, a circuit breaker of a switchgear operating under vacuum and another electric circuit. When a displacement occurs in the electric circuit when the contact of the circuit breaker is opened and closed, the flexible conductor is displaced so that the stress is not transmitted to the electric circuit of the connection destination. The flexible conductor 20 of the present embodiment covers the upper and lower sides in the stacking direction of the copper foils 1, 1... Where the high electric field is generated with the stainless steel foils 2a and 2b. Fig. 3 shows the impulse breakdown voltage of a quasi-equal electric field gap with a distance of 5 mm. ^-6 It is the bar graph which showed the result measured under the high vacuum of Torr. Measurements are made on oxygen-free copper forming the copper foil 1 and stainless steel forming the stainless steel foils 2a and 2b, and the vertical axis indicates the breakdown voltage. From this graph, it can be seen that stainless steel shows a breakdown voltage about 1.3 times that of oxygen-free copper. The magnitude relationship of the withstand voltage is the same even under an unequal electric field such as the end of the foil of the present embodiment.
[0035]
Thus, since the stainless steel foils 2a and 2b having a higher withstand voltage than copper under vacuum cover only the upper and lower portions in the stacking direction in which the high electric field of the conductive band portion 10 is generated, the area having the maximum electric field strength. Is not excessive. Accordingly, the flexible conductor 20 of the present embodiment has a higher withstand voltage than the flexible conductor of only the copper foil 1, and improves the withstand voltage characteristics. Further, since the stainless steel foils 2a and 2b have the same degree of elasticity as the copper foil 1, the stainless steel foils 2a and 2b do not hinder the displacement of the copper foil 1, and There is no displacement away.
[0036]
Therefore, the flexible conductor 20 of the present embodiment has good withstand voltage characteristics under vacuum, and thus can prevent a ground fault discharge to a grounded vacuum vessel. Further, when used in a three-phase AC circuit, it is possible to prevent interphase discharge with other phase charging parts arranged in the vicinity. As a result, by using the flexible conductor 20 of the present embodiment, it is possible to provide a switchgear that is highly reliable against dielectric breakdown and has a reduced size.
[0037]
Embodiment 2. FIG.
A flexible conductor according to Embodiment 2 of the present invention will be described with reference to the drawings. FIG. 4 is a cross-sectional view of the flexible conductor according to the second embodiment, and is a cross-sectional view seen from the side corresponding to the line II-II in FIG. Dozens of strip-shaped copper foils 1 are stacked with a predetermined gap in the thickness direction, and strip-shaped stainless steel foils 2c are stacked in such a manner as to be sandwiched between the copper foils 1 respectively. . The copper foils 1, 1... Form a conductive band portion 10, and the stainless steel foils 2 c, 2 c... Form an insulation auxiliary band, and these are alternately laminated to constitute a flexible conductor.
[0038]
The copper foil 1 is made of oxygen-free copper and has a length of 150 mm, a width (W1) of 50 mm, and a thickness of 0.1 mm. The stainless steel foil 2c has a larger width dimension (W2) than the copper foil 1, and the width direction both edges 2e, 2e of the stainless steel foil 2c are on both outer sides than the width direction both edges 1e, 1e of the copper foil 1. It extends and is exposed. The width dimension W2 of the stainless steel foil 2c is, for example, 52 mm. The length of the stainless steel foil 2 c is the same as that of the copper foil 1, and the thickness is preferably a dimension that obtains the same degree of elasticity as the copper foil 1. In the present embodiment, the stainless steel alloy foil 2c has a thickness of 0.1 mm. In addition, it is preferable that the dimension of the copper foil 1 is set to an appropriate value depending on the magnitude of the flowing current, the distance between the two electric circuits to be connected, and the like, and is not limited to the above dimensions. The width dimension W2 of the stainless steel foil 2c is not limited to the above, and may be a dimension larger than that of the copper foil 1.
[0039]
The laminated copper foils 1, 1... And stainless steel foils 2c, 2c... Are gradually brought into contact with each other at both ends in the length direction, and are fixed by a foil pressing material. Each of the foil pressing members is connected to one end of the electric circuit terminal. The foil retainer and the electric circuit terminal are the same as those in the first embodiment described above, and a description thereof is omitted. As shown in FIG. 4, for example, the ground potential conductor 9, which is the inner wall surface of the vacuum vessel, is disposed at a position facing one end surface in the width direction of the flexible conductor. That is, it faces the protruding end surface in the width direction of the stainless steel foil 2c.
[0040]
The flexible conductor having the above-described configuration is connected between, for example, a circuit breaker and another electric circuit of a switchgear operating under vacuum. When a displacement occurs in the electric circuit when the contact of the circuit breaker is opened and closed, the flexible conductor is displaced so that the stress is not transmitted to the electric circuit of the connection destination. In the flexible conductor of the second embodiment, the edge 2e of the stainless steel foil 2c is exposed at both ends in the width direction where the high electric field is generated, and the edge 1e of the copper foil 1 is the stainless steel foil. Since it is hidden by the edge 2e of 2c, a high electric field is not generated. Although a high electric field is generated at the edge 2e of the exposed stainless steel foil 2c, as described above (see FIG. 3), stainless steel has a higher withstand voltage than the copper foil under vacuum. Therefore, the flexible conductor of the second embodiment has a higher withstand voltage than that of the conventional flexible conductor in which the widths of the copper foil and the stainless steel foil are equal, and dielectric breakdown is prevented.
[0041]
In FIG. 4, the ground potential conductor 9 is located only on one side in the width direction of the copper foil 1 and the stainless steel foil 2c, but may be located on both sides. In addition, when used in a three-phase AC circuit, a charging portion of another phase may be arranged instead of the ground potential conductor 9. Further, when the ground potential conductor 9 that generates a high electric field in the flexible conductor, the charging portion, etc. are arranged only on one side of the flexible conductor, the end portion on the side where the flexible conductor is not arranged has the same length as the conventional one. That is, the copper foil 1 and the stainless steel foil 2c may be laminated with their end portions in the width direction aligned.
[0042]
As described above, the flexible conductor according to the second embodiment has good withstand voltage characteristics under vacuum, and thus can prevent a ground fault discharge to the grounded vacuum vessel. Further, when used in a three-phase AC circuit, it is possible to prevent interphase discharge with other phase charging parts arranged in the vicinity. As a result, by using the flexible conductor according to the second embodiment, it is possible to provide a switchgear having high reliability with respect to dielectric breakdown and having a reduced size.
[0043]
In addition, although the flexible conductor of Embodiment 2 has demonstrated the case where the copper foil 1 was distribute | arranged to the outermost layer of the lamination direction, it is not restricted to this, The thing of the same dimension as stainless steel foil 2c is used. It may be arranged in the outermost layer. In this case, the same effect as in the first embodiment is obtained, and the withstand voltage characteristics are further improved.
[0044]
Embodiment 3 FIG.
A flexible conductor according to Embodiment 3 of the present invention will be described with reference to the drawings. 5 is a cross-sectional view of a flexible conductor according to Embodiment 3, and is a cross-sectional view seen from the side corresponding to the line II-II in FIG. Dozens of strip-shaped copper foils 1 (conductive bands) are laminated with a predetermined gap in the thickness direction to form a conductive band portion. The copper foil 1 is made of oxygen-free copper and has a length of 150 mm and a thickness of 0.1 mm. The copper foils 1, 1... Have different width dimensions in the laminating direction, the width W3 of the copper foil 1 on both end sides in the laminating direction is 35 mm, and the width W4 of the copper foil 1 on the center side in the laminating direction is 70mm. That is, the width dimension of the copper foil 1 increases as it approaches the center from the upper and lower ends, and has the maximum width at the center. The conductive band portion has an elliptical shape in cross-sectional view. In addition, it is preferable that the dimension of the copper foil 1 is set to an appropriate value depending on the magnitude of the flowing current, the distance between the two electric circuits to be connected, and the like, and is not limited to the above dimensions. The width dimension of the copper foil 1 should just be the largest in the center side of the lamination direction.
[0045]
The laminated copper foils 1, 1... Are gradually brought into contact with each other at both ends in the length direction, and are fixed by a foil pressing material. Each of the foil pressing members is connected to one end of the electric circuit terminal. The foil retainer and the electric circuit terminal are the same as those in the first embodiment described above, and a description thereof is omitted. As shown in FIG. 5, for example, the ground potential conductor 9 which is the inner wall surface of the vacuum vessel is disposed at a position facing one end surface in the width direction of the conductive band.
[0046]
The flexible conductor having the above-described configuration is connected between, for example, a circuit breaker and another electric circuit of a switchgear operating under vacuum. When a displacement occurs in the electric circuit when the contact of the circuit breaker is opened and closed, the flexible conductor is displaced so that the stress is not transmitted to the electric circuit of the connection destination. In the flexible conductor according to the third embodiment, the distance from the ground potential conductor 9 to the end surface in the width direction of the copper foil 1 facing the conductor is different in the stacking direction of the copper foil 1. The end surface in the width direction of the copper foil 1 is a place where a high electric field is generated. The same high electric field is generated at the end of the copper foil 1 at the center in the stacking direction, but the copper foil 1 at both ends in the stacking direction is far from the ground potential conductor 9 than the copper foil 1 at the center. However, the generated electric field strength is lowered. That is, the narrower the copper foil 1, the lower the electric field strength generated at the end thereof, and the lower the electric field strength generated in the entire conductive band. Therefore, the flexible conductor of the third embodiment has improved withstand voltage characteristics and prevents dielectric breakdown.
[0047]
In FIG. 5, the ground potential conductor 9 is located only on one side in the width direction of the copper foil 1, but may be located on both sides. In addition, when used in a three-phase AC circuit, a charging portion of another phase may be arranged instead of the ground potential conductor 9. Further, when the ground potential conductor 9 that generates a high electric field in the flexible conductor, the charging portion, etc. are arranged only on one side of the flexible conductor, the end portion on the side where the flexible conductor is not arranged has the same length as the conventional one. That is, the end portions may be aligned and laminated.
[0048]
Thus, since the flexible conductor of this Embodiment 3 has a favorable withstand voltage characteristic in a vacuum, it can prevent the ground fault discharge with respect to the grounded vacuum vessel. Further, when used in a three-phase AC circuit, it is possible to prevent interphase discharge with other phase charging parts arranged in the vicinity. As a result, by using the flexible conductor according to the third embodiment, it is possible to provide a switchgear having high reliability with respect to dielectric breakdown and having a reduced size.
[0049]
In addition, although the flexible conductor of Embodiment 3 demonstrated the case where only copper foil was used as a conductive belt, it is not restricted to this, Stainless steel of the width W3 mentioned above only in the outermost layer of the lamination direction Steel foil may be arranged. In this case, the same effect as in the first embodiment is obtained, and the withstand voltage characteristics are further improved.
[0050]
Embodiment 4 FIG.
A flexible conductor according to Embodiment 4 of the present invention will be described with reference to the drawings. 6 is a cross-sectional view of the flexible conductor according to the fourth embodiment, and is a cross-sectional view seen from the side corresponding to the line II-II in FIG. 34 pieces of copper foils 1, 1... Are stacked with different width dimensions in the stacking direction. The width W5 of the copper foil 1 on both ends in the stacking direction is 35 mm, and the 14 copper foils 1 on the center side in the stacking direction have a width W6 of 70 mm. In Embodiment 4, the width dimension of the copper foil 1 increases as it approaches the center from the upper and lower ends, and the 14 copper foils 1, 1,... At the center have the maximum width. Other configurations are the same as those of the third embodiment, and the description thereof is omitted. In addition, it is preferable that the dimension of the copper foil 1 is set to an appropriate value depending on the magnitude of the flowing current, the distance between the two electric circuits to be connected, and the like, and is not limited to the above dimensions. It is sufficient that the width dimension of the plurality of copper foils 1 is maximum at the center side in the stacking direction.
[0051]
The flexible conductor having the above-described configuration is connected between, for example, a circuit breaker and another electric circuit of a switchgear operating under vacuum. When a displacement occurs in the electric circuit when the contact of the circuit breaker is opened and closed, the flexible conductor is displaced so that the stress is not transmitted to the electric circuit of the connection destination. In the flexible conductor of the fourth embodiment, as in the third embodiment, the narrower the copper foil 1, the lower the electric field intensity generated at the end thereof, the improved voltage characteristics, and the prevention of dielectric breakdown. Is done. In addition, since a plurality of copper foils 1 having the same maximum width are stacked on the center side in the stacking direction, the flexible conductor of the fourth embodiment has a maximum width of copper according to the energization current of the switchgear. By adjusting the number of foils, it can be used in common for a plurality of switching devices having different energization capacities.
[0052]
In FIG. 6, the ground potential conductor 9 is located only on one side in the width direction of the copper foil 1, but may be located on both sides. In addition, when used in a three-phase AC circuit, a charging portion of another phase may be arranged instead of the ground potential conductor 9. Further, when the ground potential conductor 9 that generates a high electric field in the flexible conductor, the charging portion, etc. are arranged only on one side of the flexible conductor, the end portion on the side where the flexible conductor is not arranged has the same length as the conventional one. That is, the end portions may be aligned and laminated.
[0053]
Thus, since the flexible conductor of this Embodiment 4 has the favorable withstand voltage characteristic in a vacuum, it can prevent the ground fault discharge with respect to the grounded vacuum vessel. Further, when used in a three-phase AC circuit, it is possible to prevent interphase discharge with other phase charging parts arranged in the vicinity. As a result, by using the flexible conductor according to the fourth embodiment, it is possible to provide a switchgear that is highly reliable against dielectric breakdown and has a reduced size.
[0054]
In addition, although the flexible conductor of Embodiment 4 demonstrated the case where only copper foil was used as a conductive belt, it is not restricted to this, Stainless steel of the width W5 mentioned above only in the outermost layer of the lamination direction Steel foil may be arranged. In this case, the same effect as in the first embodiment is obtained, and the withstand voltage characteristics are further improved.
[0055]
Embodiment 5. FIG.
A flexible connecting member according to Embodiment 5 of the present invention will be described with reference to the drawings. FIG. 7 is a perspective view of a flexible connecting member according to the fifth embodiment. As shown in FIG. 7, dozens of strip-like copper foils 1 are laminated with a gap of 0.2 mm in the thickness direction, and the conductive strips 10 are arranged on both outer sides in the stacking direction. A flexible conductor 20 is formed of the stainless steel foils 2a and 2b (insulation auxiliary bands). The flexible conductors 20 are gradually narrowed and brought into contact with each other at both ends in the length direction, and are fixed by the foil pressing member 3. Each of the foil pressing members is connected to one end of an electric circuit terminal (not shown). In addition, the flexible conductor 20 is the same as that of Embodiment 1 mentioned above, and it abbreviate | omits about the material of the copper foil 1 and stainless steel foil 2a, 2b, and its structure.
[0056]
On the outer periphery of the flexible conductor 20, a spiral shield 5 formed of a linear or thin plate-like stainless steel is wound with a predetermined spiral interval and a spiral diameter. In this embodiment, the wire diameter of the spiral shield 5 is 1.5 mm, the spiral interval is 5 mm, and the spiral diameter is such that the spiral shield 5 is separated from the flexible conductor 20 to the outer peripheral side by 5 mm. One end 5a of the spiral shield 5 is fixed to the foil retainer 3 by a spiral shield retainer 6, and the other end 5b is a free end. The spiral shield 5 only needs to be formed of a conductor, and stainless steel having good withstand voltage characteristics under vacuum is preferable. Moreover, the dimension of the spiral shield 5 and the space | interval of a spiral are not restricted to the above-mentioned dimension, What is necessary is just a dimension in which an electric field relaxation effect is exhibited. This dimension is limited to the range of wire diameter, helix spacing, and helix diameter that is expected to be obtained by performing electric field calculation on the length of the copper foil 1 and then experimented with candidate shapes. To be determined.
[0057]
The flexible connecting member having the above-described configuration is connected between, for example, a circuit breaker of the switchgear operating under vacuum and another electric circuit. When displacement occurs in the electric circuit when the contact of the circuit breaker is opened and closed, the flexible connecting member is displaced so that the stress is not transmitted to the electric circuit of the connection destination. A voltage of 100 kV was applied to the flexible connection member in which the spiral shield 5 was connected to the flexible conductor 20 at the same potential, and the electric field strength on the surface of the spiral shield 5 was measured. FIG. 8 is a bar graph showing the results, and the vertical axis shows the electric field strength on the surface of the flexible connecting member. For comparison, the electric field strength at the edge in the width direction of a conventional flexible connecting member not provided with a spiral shield is measured and similarly shown. The ground potential conductor 9 is disposed at a position facing one end surface of the copper foil 1 in the width direction, and the distance between the spiral shield 5 and the ground potential conductor 9 is 20 mm. In the comparative example, the distance between the copper foil and the ground potential conductor 9 is 25 mm.
[0058]
From the graph, the surface electric field of the flexible connecting member of the fifth embodiment was 10.2 kV / mm 2. On the other hand, in the comparative example in which the spiral shield is not disposed, the distance between the surface of the flexible connecting member and the ground potential conductor 9 is 35 kV / mm although it is 5 mm longer than the present embodiment. From the above results, the flexible connecting member of the fifth embodiment has the electric field relaxation effect by reducing the electric field strength of the surface by the spiral shield 5. This is considered to be due to the fact that the curvature of the spiral shield 5 which is the outermost layer of the flexible connecting member is larger than that of the strip conductor, and the interaction between the adjacent linear conductors wound around the spiral shield 5.
[0059]
As described above, since the flexible connecting member of the fifth embodiment can obtain an electric field relaxation effect, it is possible to prevent a ground fault discharge to the grounded vacuum vessel. Further, when used in a three-phase AC circuit, it is possible to prevent interphase discharge with other phase charging parts arranged in the vicinity. As a result, by using the flexible connecting member of the fifth embodiment, it is possible to provide a switchgear that is highly reliable against dielectric breakdown and has a reduced size. Further, since the spiral shield 5 itself is also flexible, it can be flexibly displaced even when the flexible connecting member is displaced.
[0060]
In addition, although the flexible connection member of Embodiment 5 demonstrated the case where the spiral shield 5 was wound around the flexible conductor of the structure of Embodiment 1, it does not restrict to this, The spiral shield 5 may be wound around the outer periphery of each flexible conductor shown in the forms 2 to 4. In these cases, the withstand voltage characteristics are further improved.
[0061]
Embodiment 6 FIG.
A flexible connecting member according to Embodiment 6 of the present invention will be described with reference to the drawings. FIG. 9 is a side view of the flexible connecting member according to the sixth embodiment, and FIG. 10 is a sectional view taken along line XX of FIG. Dozens of strip-shaped copper foils 1 (conducting bands) are laminated with a predetermined gap in the thickness direction to form a flexible conductor. The copper foil 1 is made of oxygen-free copper and has a length of 150 mm, a width of 50 mm, and a thickness of 0.1 mm. The dimension of the copper foil 1 is preferably set to an appropriate value depending on the magnitude of the flowing current, the distance between the two electric circuits to be connected, and the like, and is not limited to the above dimensions. The laminated copper foils 1, 1... Are gradually brought into contact with each other at both ends in the length direction, and are fixed by a foil pressing material. Each of the foil pressing members is connected to one end of the electric circuit terminal. The foil retainer and the electric circuit terminal are the same as those in the first embodiment described above, and a description thereof is omitted.
[0062]
Stainless steel cover conductors (electric field relaxation shields) 7 and 7 are arranged on the outer periphery of both ends in the length direction of the flexible conductor, and the distance between the cover conductors 7 and 7 is 20 mm to 40 mm. Have. Each of the cover conductors 7 is composed of two cover conductor pieces 71 and 72 disposed opposite to both end faces in the width direction of the copper foils 1, 1. Are in contact with both end faces in the width direction. Further, the cover conductor pieces 71 and 72 are formed in a shape in which the opposing portion of the copper foil 1 is a flat plate and the upper and lower ends 7a and 7b are curved inward with an arbitrary curvature. The upper and lower ends 7 a and 7 b have an effect of relaxing a high electric field generated on the laminated surface of the copper foil 1. The cover conductor pieces 71 and 72 are formed to have a thickness of 1 mm in this embodiment in consideration of the ease of pressing the curved portion. Each cover conductor 7 is brazed and joined at one end to the foil pressing member 3, and the other end is a free end. Thereby, it can respond to the displacement of a flexible conductor.
[0063]
The cover conductor 7 is preferably made of stainless steel with good withstand voltage characteristics under vacuum, but may be made of other materials as long as it is a conductor. Further, the side of the cover conductors 7 and 7 facing each other may be formed in a curved shape or may not be curved. Further, the cover conductor 7 may have a flat plate shape in which the upper and lower ends 7a and 7b are not curved. Furthermore, as described above (FIG. 10), for example, when two ground potential conductors 91 and 92 such as the inner wall surface of the vacuum vessel are arranged at positions facing both end faces in the width direction of the flexible conductor, The cover conductor pieces 71 and 72 are preferably disposed to face the ground potential conductors 91 and 92, respectively. Although not shown, an end portion of the flexible connecting member may be disposed instead of the ground potential conductor 91. As described above, the cover conductor piece may be provided only on one side depending on the situation of the members disposed around the periphery.
[0064]
The flexible connecting member having the above-described configuration is connected between, for example, a circuit breaker of the switchgear operating under vacuum and another electric circuit. When displacement occurs in the electric circuit when the contact of the circuit breaker is opened and closed, the flexible connecting member is displaced so that the stress is not transmitted to the electric circuit of the connection destination. Since the flexible connecting member of the sixth embodiment covers the end face in the width direction of the copper foil 1 where a high electric field is generated with a conductor, an electric field relaxation effect is obtained. Below, the result of having investigated about the breakdown voltage of the flexible connection member of this Embodiment is shown.
[0065]
FIG. 11 is a graph showing the measurement result of the breakdown voltage of the flexible connecting member. The vertical axis represents the breakdown voltage, and the horizontal axis represents the distance between the cover conductor piece and the ground potential conductor. This breakdown voltage is obtained by arranging the cover conductor of the flexible connection member and the extremely large flat ground conductor so as to face each other and changing the distance. ^-6 Measured in high vacuum at Torr. In the graph, '○' indicates the breakdown voltage when the distance between the cover conductors of the present embodiment is 20 mm, '□' indicates the breakdown voltage when the distance between both the cover conductors is 40 mm, and '×' indicates that the cover conductor is arranged. The breakdown voltage of the conventional example which has not been shown is shown. As can be seen from the graph, the flexible connection member of the sixth embodiment has a higher breakdown voltage than the conventional example in which no cover conductor is provided. For example, when the distance between the cover conductors is 40 mm, when the distance between the cover conductor piece and the ground potential conductor is the same, the breakdown voltage is approximately twice that of the conventional case. When the distance between cover conductors is 20mm, it is almost 3 times. Therefore, in the sixth embodiment, by providing the cover conductor 7, the withstand voltage characteristic is improved without covering the entire outer periphery of the longitudinal end portion of the flexible connecting member with the cover conductor. Therefore, the withstand voltage characteristic is improved and the dielectric breakdown is prevented.
[0066]
As described above, since the flexible connecting member of the sixth embodiment has good withstand voltage characteristics under vacuum, it is possible to prevent a ground fault discharge with respect to the grounded vacuum vessel. Further, when used in a three-phase AC circuit, it is possible to prevent interphase discharge between the charging portions of other phases arranged in the vicinity. As a result, by using the flexible connecting member of the sixth embodiment, it is possible to provide a switchgear that is highly reliable against dielectric breakdown and has a reduced size.
[0067]
The cover conductor pieces 71 and 72 are not necessarily in contact with the end face of the copper foil 1 and may be in a non-contact manner and have an arbitrary gap. Breakage when the distance between the cover conductor pieces 71 and 72 and the copper foil 1 is 4.7 mm, the distance between the cover conductor 7 and the flat ground potential conductor is 7.7 mm, and the distance between the cover conductors 7 and 7 is 20 mm. The voltage is 260kV. That is, even if a distance is provided between the cover conductor 7 and the copper foil 1, the withstand voltage characteristic is improved as compared with the case without the cover conductor 7.
[0068]
Embodiment 7 FIG.
In the above-described flexible connecting member of the sixth embodiment, the case where the cover conductor 7 is arranged on the flexible conductor having a laminated structure of only the copper foil 1 is described. However, the present invention is not limited to this. The cover conductor 7 may be arranged on the end face of each flexible conductor shown in the first to fourth embodiments. In these cases, the withstand voltage characteristics are further improved. FIG. 12 is a cross-sectional view of a flexible connecting member in which a cover conductor is arranged on the flexible conductor shown in the third embodiment. As shown in the figure, the flexible conductor is formed of copper foils 1, 1,... Having a narrow width at both ends in the laminating direction and wider at the center, and is opposed to the end face in the width direction of the flexible conductor. Thus, the cover conductor 7 is arranged without contact. On both outer sides of the cover conductor 7, ground potential conductors 91 and 92 are arranged to face each other. The cover conductor 7 is composed of cover conductor pieces 71 and 72 having the same material and shape as in the sixth embodiment, and a description thereof will be omitted. As described above, according to the seventh embodiment, the cover conductor 7 is disposed on the flexible conductor having good withstand voltage characteristics so as to cover the end face in the width direction, and therefore the withstand voltage characteristics are further improved.
[0069]
As described above, in the sixth and seventh embodiments, by disposing the cover conductors 7 and 7, the withstand voltage characteristic of the flexible connecting member is improved, and the reliability against dielectric breakdown is improved. Also, by shortening the insulation distance by this improvement, the flexible connecting member can be reduced in size while maintaining the same reliability.
[0070]
Embodiment 8 FIG.
FIG. 13 is a side view of the flexible connecting member according to the eighth embodiment, and FIG. 14 is a sectional view taken along line XIV-XIV in FIG. Dozens of strip-shaped copper foils 1 (conducting bands) are laminated with a predetermined gap in the thickness direction to form a flexible conductor. The copper foil 1 is made of oxygen-free copper and has a length of 150 mm, a width of 50 mm, and a thickness of 0.1 mm. The dimension of the copper foil 1 is preferably set to an appropriate value depending on the magnitude of the flowing current, the distance between the two electric circuits to be connected, and the like, and is not limited to the above dimensions. The laminated copper foils 1, 1... Are gradually brought into contact with each other at both ends in the length direction, and are fixed by a foil pressing material. Each of the foil pressing members is connected to one end of the electric circuit terminal. The foil retainer and the electric circuit terminal are the same as those in the first embodiment described above, and a description thereof is omitted.
[0071]
An insulating cover (insulating portion) 8 made of alumina or heat-resistant glass is disposed on the outer periphery of the flexible conductor. The insulating cover 8 is composed of flat insulating cover pieces 81 and 82 which are opposed to both end faces in the width direction of the copper foils 1, 1. Is not in contact with both end faces in the width direction. The thickness of the insulating cover pieces 81 and 82 is preferably such that the strength of the insulating material can be obtained. The insulating cover 8 covers the entire edge in the length direction of the conductive band, and one end of the insulating cover 8 is brazed to one of the foil pressing members 3 and the other end is a free end. Thereby, it can respond to the displacement of a flexible conductor. The material of the insulating cover 8 is preferably a vacuum insulating material such as alumina or heat-resistant glass.
[0072]
The flexible connecting member having the above-described configuration is connected between, for example, a circuit breaker of the switchgear operating under vacuum and another electric circuit. When displacement occurs in the electric circuit when the contact of the circuit breaker is opened and closed, the flexible connecting member is displaced so that the stress is not transmitted to the electric circuit of the connection destination. In the flexible connection member of the eighth embodiment, the end surface in the width direction of the copper foil 1 where a high electric field is generated is covered with an insulating material, and thus is emitted from a high electric field portion such as the end surface of the flexible connection member. The field emission electrons are shielded by the insulator and cannot move to the counterpart conductor. In vacuum discharge, field electrons are generated from a high electric field portion on the cathode side, and the emitted electrons move while accelerating to the anode and are considered to be one of the triggers of discharge. Therefore, the breakdown voltage rises by preventing the movement of field emission electrons by the insulator.
[0073]
As described above (see FIG. 14), for example, when the two ground potential conductors 91 and 92 such as the inner wall surface of the vacuum vessel are arranged at positions facing the both end surfaces in the width direction of the flexible conductor, It is preferable that the insulating cover pieces 81 and 82 are disposed opposite to the ground potential conductors 91 and 92, respectively. Although not shown, an end portion of the flexible connecting member may be disposed instead of the ground potential conductor 91. In this way, the insulating cover piece may be installed only on one side depending on the situation of the members disposed around. The insulating cover 8 may have a shape in which each of the upper and lower ends is curved inward.
[0074]
By providing the insulating cover 8 in this way, the withstand voltage characteristic under vacuum is improved. When the insulation distance is shortened by this improvement, the flexible connecting member can be reduced in size while maintaining the same reliability. In addition, when the insulating cover 8 is disposed in the same manner as the conventional insulation distance, the reliability against dielectric breakdown is improved.
[0075]
Embodiment 9 FIG.
In the above-described flexible connecting member according to the eighth embodiment, the case where the insulating cover 8 is disposed on the flexible conductor having the laminated structure of only the copper foil 1 is described. However, the present invention is not limited to this. The insulating cover 8 may be arranged on each flexible conductor shown in the first to fourth embodiments. In these cases, the withstand voltage characteristics are further improved. FIG. 15 is a cross-sectional view of a flexible connecting member in which an insulating cover is arranged on the flexible conductor shown in the fourth embodiment. As shown in the figure, the flexible conductor is formed of copper foils 1, 1,... Having a narrow width at both ends in the laminating direction and wider at the center, and is opposed to the end face in the width direction of the flexible conductor. Thus, the insulating cover 8 is arranged in a non-contact manner. The insulating cover 8 is composed of insulating cover pieces 81 and 82 having the same material and shape as those of the eighth embodiment, and the description thereof is omitted. As described above, since the insulating cover 8 is arranged on the flexible conductor having a high withstand voltage so as to cover the end face in the width direction, the withstand voltage characteristic is further improved.
[0076]
【The invention's effect】
As described above, according to the flexible conductors of the first to third inventions, the auxiliary insulation bands exposed on both outer sides of the conductive band portions in the stacking direction, or the conductive band portions are alternately stacked and the width direction Since the auxiliary insulation band exposed at the edge side is provided, the withstand voltage characteristic of the flexible conductor under vacuum is improved, and dielectric breakdown is prevented.
[0077]
According to the flexible conductors according to the fourth to sixth inventions, since the conductive band portion has the widest width conductive band on the center side in the stacking direction, the electric field strength generated at the end portion in the width direction is The center side is the same level as the conventional one, and it is reduced at both ends in the stacking direction. Thereby, an electric field relaxation effect is obtained and dielectric breakdown is prevented.
[0078]
According to the flexible connecting member of the seventh invention, the conductor is spirally wound around the outer periphery of the flexible conductor with improved withstand voltage characteristics as described above or the flexible conductor in which dielectric breakdown is prevented. Therefore, the electric field strength of the surface generated in the flexible conductor can be further reduced.
[0079]
According to the flexible connecting member according to the eighth or ninth invention, since the end face in the width direction of the conductive band is covered with the electric field relaxation shield part, the withstand voltage of the flexible connecting member is increased and the dielectric breakdown is prevented. it can. Further, since the end face in the width direction of the flexible conductor with improved withstand voltage characteristics as described above or the flexible conductor in which dielectric breakdown is prevented is covered with the electric field relaxation shield portion, the withstand voltage is further increased.
[0080]
According to the flexible connecting member according to the tenth aspect of the invention, since the electric field relaxation shield portion is made of a conductor, the electric field strength of the flexible conductor is reduced, and dielectric breakdown can be prevented.
[0081]
According to the flexible connecting member of the eleventh aspect of the invention, since the end surface in the width direction of the conductive band is covered with the insulating portion, the field emission electrons emitted from the end surface are shielded by the insulating portion, and vacuum discharge can be prevented. The present invention has excellent effects.
[0082]
[Brief description of the drawings]
FIG. 1 is a perspective view showing a structure of a flexible conductor according to a first embodiment.
FIG. 2 is a cross-sectional view taken along line II-II in FIG.
FIG. 3 is a graph illustrating the effect of the flexible conductor according to the first embodiment.
4 is a cross-sectional view showing a structure of a flexible conductor according to Embodiment 2. FIG.
5 is a cross-sectional view showing a structure of a flexible conductor according to Embodiment 3. FIG.
FIG. 6 is a cross-sectional view showing a structure of a flexible conductor according to a fourth embodiment.
7 is a perspective view showing a structure of a flexible connecting member according to Embodiment 5. FIG.
FIG. 8 is a graph for explaining the effect of the flexible connecting member according to the fifth embodiment.
FIG. 9 is a side view showing a structure of a flexible connecting member according to a sixth embodiment.
10 is a cross-sectional view taken along line XX of FIG.
FIG. 11 is a graph for explaining the effect of the flexible connecting member according to the sixth embodiment.
12 is a cross-sectional view showing a structure of a flexible connection member according to Embodiment 7. FIG.
FIG. 13 is a side view showing the structure of a flexible connecting member according to an eighth embodiment.
14 is a cross-sectional view taken along line XIV-XIV in FIG.
FIG. 15 is a cross-sectional view showing a structure of a flexible connecting member according to a ninth embodiment.
FIG. 16 is a partial cross-sectional view showing the structure of a conventional flexible conductor.
[Explanation of symbols]
1 Copper foil, 1e Width direction edge of copper foil, 2a, 2b, 2c Stainless steel foil,
2e Width direction edge of stainless steel foil, 3 foil presser, 4 electric circuit terminal, 5 spiral shield, 6 spiral shield presser, 7 cover conductor, 8 insulating cover, 9 ground potential conductor, 10 conductive strip, 11 collective conductor 20 Flexible conductor,
71, 72 Cover conductor piece, 81, 82 Insulation cover piece, 91, 92 Ground potential conductor.

Claims

A plurality of conductive bands are laminated, and a conductive band part that electrically connects two electrical paths, and an insulation assistant that is arranged on both outer sides in the stacking direction of the conductive band part and has approximately the same elasticity as the conductive band A flexible conductor comprising a band.

A plurality of conductive bands are stacked, and a conductive band portion that electrically connects two electric paths, and a width that is wider than the conductive band, and an edge in the width direction projects so as to protrude from the conductive band. A flexible conductor comprising an auxiliary insulation band arranged between the bands.

The flexible conductor according to claim 1 or 2, wherein the conductive band is made of copper and the auxiliary insulation band is made of stainless steel.

A conductive band portion in which a plurality of conductive bands for electrically connecting two electric paths are stacked, and the conductive band portion is arranged with the conductive band having a width dimension wider than both ends on the center side in the stacking direction. A flexible conductor.

The flexible conductor according to claim 4, wherein the conductive band portion has a width of the conductive band that increases from the both end sides to the center side in the stacking direction.

The flexible conductor according to claim 4, wherein the conductive band portion is provided with a plurality of conductive bands having the widest width dimension on the center side in the stacking direction.

The flexible conductor according to any one of claims 1 to 6 and a spiral conductor wound around an outer periphery of the flexible conductor, one end of which is electrically connected to an end of the flexible conductor, A flexible connecting member, wherein the other end includes a helical conductor which is a free end.

A flexible conductor formed by laminating a plurality of conductive bands for electrically connecting two electric circuits, and an electric field relaxation shield portion that covers the width direction end face of the conductive band and exposes the conductive band on the end face in the laminated direction And a flexible connecting member.

A flexible conductor comprising: the flexible conductor according to any one of claims 1 to 6; and an electric field relaxation shield portion that covers a width direction end face of the conductive band and exposes the conductive band of the end face in the stacking direction. Sex connection member.

10. The electric field relaxation shield portion is a conductive plate disposed on each of both ends in the length direction of the conductive band, and each electric field relaxation shield portion is a conductive plate disposed opposite to both end surfaces in the width direction of the conductive band. Flexible connection member.

It comprises a flexible conductor formed by laminating a plurality of conductive bands for electrically connecting two electric paths, and an insulating portion disposed opposite to each of the end faces in the width direction of the conductive bands. Flexible connection member.