JP5936969B2 - Heat source machine operation control method in cold / hot water supply system - Google Patents

Description

  The present invention relates to a heat source machine operation control technique of a cold / hot water supply system using steam as a drive source.

2. Description of the Related Art Conventionally, a cold / hot water supply system is known that combines a steam-fired refrigerator and a steam heat exchanger that use waste heat from a distributed power source (cogeneration) or steam supplied from a steam boiler as a driving source. As for the steam chiller, a technique (for example, Patent Documents 1 and 2) for improving efficiency and a technique (for example, Patent Document 3) for improving partial load efficiency have been proposed.
When operating a steam-fired refrigerator, priority should be given to cogeneration steam with a relatively small energy intensity rather than steam with a steam boiler with a relatively large energy intensity in order to improve energy savings. .

  On the other hand, in a conventional hot / cold water supply system equipped with multiple heat source devices that use steam as the drive source, each steam chiller individually adjusts the steam valve opening according to the outlet temperature, high temperature regenerator temperature and pressure. In addition, the steam heat exchanger controls the amount of steam input by adjusting the opening of the steam valve corresponding to the outlet temperature.

JP 2001-56160 A JP 2001-56161 A JP 2000-283589 A

When the above-mentioned control is adopted, when the steam consumption is large, a steam boiler with a relatively large energy unit is started as the pressure of the steam system is lowered, and the energy saving operation cannot be maintained. There is.
In order to solve such problems, an object of the present invention is to provide a heat source machine operation control technology excellent in energy saving that enables only a steam having a relatively small energy intensity to be input to the heat source machine side. .

The gist of the present invention is as follows. That is, the heat source machine operation control method of the cold / hot water supply system according to the present invention is:
(1) A heat source machine operation control method in a cold / hot water supply system comprising: a plurality of steam generation sources that produce steam of different energy intensity units; and a plurality of heat source units that produce cold / hot water using the steam of the steam generation source. Because
Perform start / stop control of each heat source unit according to a preset startup priority so that only steam from a steam source with a specific energy intensity (hereinafter referred to as specific steam) is supplied to the heat source system. A heat source machine operation control method in a cold / hot water supply system.

In the present invention, the “cold / warm water supply system” refers to a system that supplies cold water or warm water produced by a heat source machine to a user's destination to perform air conditioning and warm water supply.
The “energy intensity” is an index that represents the amount of primary energy input per unit production steam, the input energy cost per unit production steam, and the carbon dioxide emissions of input energy per unit production steam. You can choose according to your purpose.

(2) In the above invention, the total amount of supplied steam (ΣSs) of the specific steam is greater than the total amount of consumed steam (ΣSd) of the currently operating heat source unit (supply margin steam amount: ΔS = ΣSs− ΣSd> 0), when starting the heat source machine (second heat source machine) with the highest start priority in the current operation stop,
When the minimum operable steam amount (Sd_min (k)) of the next heat source unit exceeds the supply surplus steam amount (ΔS),
Regardless of the startup priority, the heat source machines in which the minimum steam volume (Sd_min (k)) is less than the supply surplus steam volume (ΔS) are sequentially raised and started.
It is characterized by that.

The minimum amount of steam that can be operated is required for starting the heat source unit.If the unit is operated without satisfying this condition, the heat source unit consumes more steam than the specific steam production amount, resulting in a large energy intensity. Steam (for example, boiler steam) is supplied.
By the control according to the present invention, the heat source system can be operated with maximum utilization of only specific steam (for example, cogeneration steam).
In addition, by operating as many heat source machines as possible that satisfy the minimum operable steam amount condition, it is possible to perform operations without wasting specific steam, and energy saving can be improved.

(3) In each of the above inventions, when performing capacity control of the heat source machine (k) currently in operation,
Based on the difference between the current steam consumption Sd (k) of the heat source unit (k) and the maximum steam amount Sd_max (k) that can be consumed by the heat source unit (k),
The upper limit opening degree (αk) of the steam valve provided for each heat source unit is controlled to increase or decrease at predetermined intervals by a predetermined increase or decrease range (β%, γ%).
However, Sd_max (k) = ΣSs (i) − (ΣSd (j) −Sd (k))
ADVANTAGE OF THE INVENTION According to this invention, it can prevent that a heat source machine consumes steam more than the generation amount of specific steam by adjusting the steam valve upper limit opening degree ((alpha) k) of a heat source machine (k).

  According to the present invention, since the operation of the heat source machine is controlled using only steam (specific steam) having a small energy intensity such as cogeneration waste heat, the air conditioning chilled water pursuing energy saving, low cost, and carbon dioxide emission control. Can be manufactured.

1 is a diagram illustrating an overall configuration of a heat source machine operation control system 1. FIG. It is a figure which shows the operation control flow in 1st embodiment. In an Example, it is a figure which shows typically the state in which supply margin ((DELTA) S) exceeds the minimum steam | vapor amount (Sd_min (k)) which can operate | move the next generator. FIG. 6 is a diagram schematically showing a state where the supply margin (ΔS) is lower than the minimum operable steam amount (Sd_min (k)) of the next engine. In the same as above, it is a diagram schematically showing a state where the supply margin (ΔS) exceeds the minimum operable steam amount (Sd_min (k)) of the generators one after another. It is a figure which shows the steam valve opening degree control flow after k machine start-up.

Hereinafter, each embodiment of the present invention will be described in more detail. Needless to say, the scope of the present invention is described in the claims and is not limited to the following embodiments.
<First embodiment>
The present embodiment relates to a mode of controlling the number of heat source units in a system including a plurality of steam drive sources having different energy intensity units.
Referring to FIG. 1, a heat source unit operation control system 1 according to the present embodiment produces a steam supply system 1A that supplies steam to each heat source unit side, and produces cold water / hot water using steam as a driving source to load side ( It is configured by a heat source machine system 1B to be supplied to a not-shown system and a control system 1C that controls the entire system.

The steam supply system 1A includes a plurality of CGS (cogeneration system) 4 (specific steam in the claims) that is a steam generation source, one or a plurality of steam boilers 5, and the generated steam once to store the generated steam. A supply header 6 distributed and supplied to the 1B side is provided as a main configuration.
The heat source system 1B includes a plurality (n units) of steam chillers 2 (2 (1) to 2 (n)) (hereinafter referred to as heat source units 2 (1) to 2 (n) as appropriate), A plurality of steam heat exchangers 3 are provided as main components.

Each heat source machine of the heat source system 1B is set with the activation priority k (k = 1 to n) shown in Table 1, and in the control flow (FIG. 2) described later, the activation / stop of each heat source machine is It is configured to be performed according to the priority order in the table.
The startup priority is set based on the energy intensity. In this embodiment, the cogeneration waste heat steam with a small energy basic unit is given priority as the specific steam.
In Table 1, the steam tank refrigerator 2 (n) is always set higher than the heat exchanger 3. However, as will be described later, the heat exchanger 3 is connected to the steam tank refrigerator 2 (k) (k) depending on the load conditions. It may be set higher than ≧ 2).

  With the above configuration, steam produced by cogeneration waste heat or boiler heating in the steam supply system 1A is supplied as a drive source to the heat source system 1B by the pipes 7a to 7c connecting the both systems via the header 6, and the heat source system In 1B, cold / hot water is manufactured and supplied to the load side (not shown).

The control system 1C of the heat source unit operation control system 1 includes a steam flow meter 8a disposed in each pipe 7a path of the steam supply system 1A and a steam flow meter disposed in each branch pipe 7c of the heat source unit system 1B. 8b and the steam valve 9, and the control part 10 which performs each calculation mentioned later based on the measured value of each of these flowmeters and steam valves, and performs a driving | operation command to the heat-source-machine system 1B side.
The control unit 10 performs the following number control, that is, start / stop control of each heat source unit based on the start priority in Table 1. In addition, capacity control of each heat source machine is performed for every heat source machine based on each exit temperature, pressure, etc.

The heat source machine operation control system 1 is configured as described above. Next, with reference to FIG. 2, an aspect of the heat source machine number control performed by the control unit 10 will be described.
During control, the steam flow meters 8a and 8b measure the steam flows Ss (i) and Sd (j) on the supply side and the consumption side (i: each steam generation source, j: each heat source machine) and collect them in the control unit 10. (S101).

Next, a comparison is made between the total supply steam amount (ΣSs (i)) and the total consumption steam amount (ΣSd (j)) at the current time (S102). Here, the total supply steam amount is the sum of cogeneration (CGS4) waste heat (specific steam), and the total consumption steam amount is the total consumption steam amount on the heat source unit side.
In the case of ΣSs <ΣSd (N in S102), since there is no steam supply capacity, the heat source machine with the lowest priority is shut down after a predetermined time has elapsed (Y in S110) (S112).

If Y in S102, that is, if ΣSs ≧ ΣSd, there is a surplus supply capacity, and the process proceeds to the activation sequence flow of the heat source units 2 (1) to 2 (n) (S103 to S109).
Specifically, it is sequentially determined for each heat source unit (k = 1 to k = n) whether the operation using the specific steam is possible.
Hereinafter, it is assumed that the flow has progressed (k <n; N in S104). The difference ΔS (= ΣSs (i) −ΣSd (j)) between the supply steam amount (ΣSs (i)) and the consumption steam amount (ΣSd (j)) is the steam required for the minimum capacity operation of the heat source unit 2 (k). It is determined whether or not the amount is greater than or equal to the amount (Sd_min (k)) (S105).

If ΔS ≧ Sd_min (k) (Y in S105), it is further determined whether or not the heat source unit 2 (k) is in operation (S106). If not in operation (N in S106), the next heat source machine is activated in accordance with the priority order (S108).
When Y in S106, that is, when the heat source device 2 (k) is in operation, the above flow (S104 to S106) is applied to the lower priority order (k = k + 1) than the heat source device 2 (k) (S107). Is done.

  During each of the above flows, when starting, stopping, increasing or decreasing the heat source unit, etc., it is set in advance for each heat source unit type, taking into account that the startup characteristics, stabilization time, etc. differ depending on the heat source unit type. The step transition time (interval) is adopted (S109).

  In addition, in this embodiment, when there was no supply capacity of specific steam in S102, the example which stopped the heat source machine of the lowest priority was shown, However, The form which uses the steam of the steam boiler 5 without stopping operation and You can also Furthermore, it can also be set as the form linked and controlled with another system which can supply steam.

<Second Embodiment>
This embodiment relates to the opening degree control flow of the k machine steam valve 9 after starting the k machine in S108 of the flow of FIG.
The k-machine steam valve 9 is controlled to open within a range of 0% ≦ αk ≦ 100%, where αk is the upper limit opening. In addition, the width when increasing or decreasing the opening is set to β% and γ%, respectively. Β and γ can be determined in advance in consideration of the allowance for the steam change rate of the steam-using facility.

Referring to FIG. 3, at the time of starting up k machine (S201), it is assumed that upper limit opening degree αk of the steam valve of k machine is 0% (S202). In the following description, it is assumed that the control has progressed (upper limit opening degree αk).
During the control, the steam flow meter of the steam supply system 1A and the heat source system 1B uses the steam consumption of the k machines (Sd (k)) (S203) and the respective steam flows Ss (i), Sd (j) Is measured. Next, the supply steam amount (ΣSs (i)) in the steam supply system and the consumption steam amount (ΣSd (j)) on the heat source system side are calculated (S204), and the maximum steam that can be consumed by the k machine is calculated. An amount Sd_max (k) is calculated (S205). Here, Sd_max (k) is expressed by the following equation.
Sd_max (k) = ΣSs (i) − (ΣSd (j) −Sd (k))

Next, the maximum steam amount Sd_max (k) that can be used for the k machine is compared with the current steam consumption Sd (k), and it is determined whether there is room for further use (S206).
When ΔSd (k) (= Sd_max (k) −Sd (k)) = 0, the current steam valve upper limit opening αk is maintained (S207).
When ΔSd (k)> 0, it is determined that there is room for use, and the steam valve upper limit opening degree αk is increased by β% (S208).
When Sd_max (k) <0, it is determined that there is no room for use, and the steam valve upper limit opening degree αk is reduced by γ% (S209).

  By the changed αk (S210), the flow of S203 to S209 is repeated. If the condition of ΔS (= ΣSs (i) −ΣSd (j)) <0 is reached during this control, the operation of the k machine is stopped by S102 in FIG.

Next, the flow of S104 to S108 in FIG. 2 will be described in more detail with an example in which the configuration of the heat source apparatus operation control system 1 in the first embodiment is simplified.
In this embodiment, the steam supply system 1A is constituted by three steam generation sources (CGS-1, 2), and the amount of generated steam of each drive source is as shown in Table 2. Further, the heat source system 1B is composed of two steam chillers (NC-1, 2) and one heat exchanger (HEX1). It shall be as follows. The steam boiler is ignored because it is not related to this control.
From Table 2, the maximum steam supply amount ΣSs (i) of the specific steam is 550 kg / h. In the following, unit display is omitted and only quantity display is used.

Hereinafter, in the initial state (k = 1 in S103), it is assumed that the heat source system side is in a state where only NC-1 is operating, and two cases where the consumed steam amount Sd (1) is 250 and 400 will be described.
(A) Case 1 (when Sd (1) = 250)
In S103, k = 1, ΣSs (i) = 550, and ΣSd (j) = 250, so ΔS = 550−250 = 300, and ΔS> Sd_min (1), that is, Y in S105.

Next, since the k machine (k = 1) is in operation (Y in S106), k = 2 (S107), and the process returns to S104. Since k <3 (Y in S104), the process further proceeds to S105, where ΔS = 250, Sd_min (2) = 200, and ΔS> Sd_min (2), that is, Y in S105. This state is schematically shown in FIG. 3 (a).
From δ = ΔS−Sd_min (2)> 0, it can be seen that there is a supply margin.
Further, since k machine (k = 2) is not in operation (N in S106), NC-2 with k = 2 is activated (S108).

(B) Case 2 (when Sd (1) = 400)
In S103, k = 1, and ΣSs (i) = 550 and ΣSd (j) = 400, so ΔS = 550−400 = 150, and ΔS <Sd_min (1), that is, N in S105.

Next, the process skips to S107 and becomes k = 2, and the process returns to S104. Since k <3 (Y in S104), the process proceeds to S105. Since ΔS = 150 and Sd_min (2) = 200, ΔS <Sd_min (2) (N in S105), that is, NC-2 cannot be activated. This state is schematically shown in FIG.
Further, the process proceeds to S107, where k = 2 + 1 = 3, and HEX-1 is activated. In this case, since ΔS = 550−400 = 150 and Sd_min (3) = 100, ΔS> Sd_min (3), that is, Y in S105. Since HEX-1 is stopped, it is activated (S108). This state is schematically shown in FIG.
From δ = ΔS−Sd_min (3)> 0, it can be seen that there is a supply margin.

  The present invention can be widely applied to cold / hot water supply systems using unused steam as a drive source regardless of applications, such as district heat supply, commercial / industrial air conditioning, and heat supply.

DESCRIPTION OF SYMBOLS 1 ... Heat source machine operation control system 1A ... Steam supply system 1B ... Heat source machine system 1C ... Control system 2 Steam steam refrigerator 3 ... Steam heat exchanger 4 ... CGS (Cogeneration system)
5. Steam boiler 6 Supply headers 7a, 7b, 7c Steam pipes 8a, 8b Steam flow meter 9 Steam valve 10 ..Control part

Claims (1)

A heat source unit operation control method in a cold / hot water supply system comprising: a plurality of steam generation sources that produce steam of different energy intensity units; and a plurality of heat source units that produce cold / hot water from the steam of the steam generation source. ,
Steam vapor source specific energy unit (hereinafter, certain of steam) only to supply to the heat source machine system, according to the preset boot priority, performs start and stop control of the heat source apparatus And
When performing capacity control of the heat source machine (k) currently in operation,
Based on the difference between the current steam consumption Sd (k) of the heat source unit (k) and the maximum steam amount Sd_max (k) that can be consumed by the heat source unit (k),
An upper limit opening degree (? K) of a steam valve provided for each heat source unit is controlled to increase or decrease at predetermined time intervals in a predetermined increase or decrease range (?%,?%). Heat source machine operation control method in cold / hot water supply system.
However, Sd_max (k) = ΣSs− (ΣSd−Sd (k))
Total amount of steam supplied for specific steam (ΣSs), total amount of steam consumed by heat source units currently in operation (ΣSd)

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