JP2010127559A - Heat source control system for air conditioning facility - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a heat source control system for an air conditioning facility, capable of optimally distributing a load to each refrigerator in accordance with the state of the load applied to an air conditioner and capable of operating a system with optimal operation efficiency. <P>SOLUTION: In the heat source control system 10, a turbo refrigerator 11 and an absorption type refrigerator 12 are arranged in parallel, and are connected to a delivery header 15 via primary side water delivery pipe lines 13, 14, respectively and further connected to a return header 19 via primary side water return pipe lines 21, 22, respectively. Bypass pipe lines 35 are provided between the primary side water delivery pipe lines 13, 14 and primary side water return pipe lines 21, 22. The heat source control system includes: flow rate controllers 55, 56 for controlling the primary pumps 23, 24 of the primary side water return pipe lines 21, 22 and the first valves 45, 46 of the primary side water delivery pipe lines 13, 14 and the second valves 47, 48 of the bypass pipe lines 35, 36; and a flow rate distribution controller 59 for controlling the flow rate controllers. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an air conditioning facility and relates to a heat source control system in which a plurality of refrigerators are arranged in parallel.

  Conventionally, in a heat source control system for large-scale air conditioning equipment used in building facilities, etc., cold water or brine (antifreeze) cooled by heat exchange with a refrigerant forming a refrigeration cycle in an evaporator of a refrigerator, or cold temperature Hot water that exchanges heat with the heat medium of the condenser (absorber) of the water machine is supplied to the heat exchanger such as an air conditioner via the forward header by at least one pump that pushes the heat medium into the refrigerator. It circulates through the return header via the secondary side return water pipe, and again to the refrigerator via the primary side pipe.

  In such a heat source control system, a plurality of refrigerators are generally arranged in parallel, and the number of operating units is controlled to cope with load fluctuations due to the outside air conditions in summer and winter. For this reason, in general, a turbo chiller exclusively for cooling and an absorption refrigerator that is also used for cooling and heating are often installed in combination.

  An example of a conventional heat source control system for air conditioning equipment is shown below. In the heat source control system 60 shown in FIG. 3, one turbo chiller 61 and one absorption chiller 62 are juxtaposed. Each refrigerator 61, 62 is connected to the forward header 65 via the primary side outgoing pipeline 63, 64, respectively. The forward header 65 is connected to an air conditioner (heat exchanger) 67 through a secondary side outgoing water pipeline 66. The air conditioner 67 is connected to a return header 69 via a secondary side return water pipe 68. The return header 69 is connected to the refrigerators 61 and 62 via primary-side return water pipes 71 and 72, respectively.

  The primary side return water pipes 71 and 72 are respectively provided with primary pumps 73 and 74 for pressure-feeding the heat medium to the refrigerators 61 and 62, respectively.

  The forward header 65 includes a first header 65 a connected to the primary side outgoing pipelines 63 and 64 and a second header 65 b connected to the secondary side outgoing pipeline 66. Between the headers 65a and 65b, secondary pumps 75a, 75b and 75c for pressure-feeding the heat medium from the first header 65a to the air conditioner 67 are provided via piping.

  Under the above configuration, the heat medium generated by each of the refrigerators 61 and 62 is mixed in the forward header 65 and sent to the air conditioner 67. Then, after the heat exchange is performed by the air conditioner 67, the heat is again sent to the refrigerators 61 and 62 through the return header 69.

  In addition, the heat source control system 60 is provided with a water temperature sensor 77 for measuring the temperature of the heat medium (outward water temperature) supplied from the forward header 65 to the air conditioner 67 in the secondary side outgoing water pipeline 66. It has been. Similarly, the secondary side return water pipe 68 is provided with a return water temperature sensor 78 for measuring the temperature of the heat medium returned to the return header 69 (return water temperature).

  The return header 69 includes a first header 69 a connected to the secondary-side return water pipe 68 and a second header 69 b connected to the primary-side return water pipes 71 and 72. Between both headers 69a and 69b, a load-side flow meter 79 for measuring the flow rate of the heat medium returned to the return header 69, that is, the flow rate of the heat medium supplied to the air conditioner 67 is provided.

  Furthermore, the heat source control system 60 is provided with a calorimeter 80 that calculates the amount of heat based on information obtained from the incoming water temperature sensor 77, the return water temperature sensor 78, and the load-side flow meter 79.

  The secondary return water pipe 68 is provided with a valve 81 for adjusting the flow rate of the heat medium supplied to the air conditioner 67 according to the load state.

  Further, between the forward header 65 (first header 65a) and the return header 69 (second header 69b), an inter-return header bypass conduit 85 that communicates the two is provided.

  Under the above configuration, when the load on the air conditioner 67 is small, the flow rate of the heat medium is reduced by restricting the valve 81. At this time, in the heat source control system 60, the flow rate of the heat medium sent to the refrigerators 61 and 62 by the primary pumps 73 and 74 is maintained at a constant amount, whereas the heat medium sent to the air conditioner 67 is changed. The flow rate decreases. For this reason, the surplus heat medium (outgoing water) is directly returned to the return header 69 via the bypass return pipe 85 without passing through the air conditioner 67. After joining with the return water, it is sent to the refrigerators 61 and 62 again.

  In the heat source control system 60, the flow rate of the heat medium sent to each of the refrigerators 61 and 62 cannot be adjusted individually. Therefore, when the heat source control system 60 is operated with a partial load as a whole, both the refrigerators 61 and 62 are operated with a partial load at the same rate.

  For example, the rated cooling capacity (maximum cooling capacity) of the air conditioner 67 is 1000 RT (refrigeration ton: 1RT = 3024 [kcal / h], 1 [cal] = 4.186 [J]), and the turbo refrigerator 61 and the absorption type In a system designed with the rated cooling capacity of the refrigerator 62 set to 500 RT each, when the load on the air conditioner 67 becomes a partial load, for example, 600 RT, the load is almost evenly applied to the two refrigerators 61 and 62. Are distributed, and both the refrigerators 61 and 62 are operated at a partial load of about 60%.

  In such a system, for example, the temperature of the heat medium generated by each of the refrigerators 61 and 62 and sent from the forward header 65 to the air conditioner 67 is set to 7 ° C., heat exchange is performed by the air conditioner 67 and returned to the return header 69. When the operation is performed with the temperature of the heat medium set at 12 ° C., the heat medium of 10080 (l / min) that is the rated flow rate is supplied to the air conditioner 67 at the peak time (at the time of rated load), and each refrigerator 61 , 62 is supplied with a heating medium of 5040 (l / min), which is a rated flow rate.

  When the partial load operation is 60%, the flow rate of the heat medium flowing to the air conditioner 67 is reduced to 6048 (l / min), whereas the flow rate flowing to each of the refrigerators 61 and 62 is 5040. A flow rate of (l / min) is maintained. Here, the surplus 4032 (l / min) heat medium flows directly to the return header 69 via the bypass header bypass passage 85. Thus, in the return header 69, the 12 ° C. return water from the air conditioner 67 is mixed with the 7 ° C. cold water that has passed through the bypass conduit 85 between the return headers, so that the water temperature is higher than the peak 12 ° C. The temperature drops to about 10 ° C. This heat medium is again sent to the refrigerators 61 and 62 by the primary pumps 73 and 74. Thereby, the load calorie | heat amount processed with each refrigerator 61,62 falls uniformly.

  Since each refrigerator is operated so that the 10 ° C return cold water reaches the 7 ° C freezer outlet cold water temperature, the temperature difference of the cold water is 12 ° C-7 ° C = 5 ° C, and 10 ° C-7 ° C = 3 It becomes a freezing operation with a temperature difference of 0 ° C. and a partial load operation of 3 ° C. difference / 5 ° C. difference = 60%.

  However, the operation efficiency differs between the turbo refrigerator 61 and the absorption refrigerator 62. The coefficient of performance (COP) showing an example of the operation efficiency of the turbo chiller 61 is larger than the COP of the absorption chiller 62, and the turbo chiller 61 operates much more at the rated time than the absorption chiller 62. Efficiency is good. For this reason, it is preferable to use the turbo refrigerator 61 preferentially as much as possible. However, in the heat source control system 60, the load is equally distributed to both the refrigerators 61 and 62 regardless of whether the operation efficiency is good or bad. . As a result, the ratio of the load heat amount processed by the absorption chiller 62 having poor operating efficiency at the time of rating is not reduced, the energy efficiency of the entire system is deteriorated, and the operating cost is increased. When viewed from another angle, the turbo chiller 61 has a characteristic that the degree of decrease in the coefficient of performance is larger than the degree of decrease in the coefficient of performance of the absorption chiller 62 at the time of partial load. Further, the turbo refrigerator 61 has a characteristic that it is difficult to cope with a very small partial load. The input energy of the coefficient of performance of the turbo chiller 61 is electric power, and the total efficiency of the absorption chiller 62 operated with gas fuel is the total efficiency (which is another example of operation efficiency) that also considers the power generation efficiency and the power transmission efficiency. Will approach. On the other hand, the absorption efficiency of the absorption refrigerator 62 hardly decreases even if it becomes a partial load. The turbo chiller 61 with a good coefficient of performance at the time of rating has a lower overall efficiency at the time of partial load, and the absorption chiller 62 may exceed the turbo chiller 61 by the total efficiency depending on the degree of partial load. Therefore, if the turbo refrigerator 61 is partially loaded at the time of partial load, the energy efficiency of the entire system is deteriorated and the operation cost is increased.

  Thus, when using a refrigerator with different operating efficiency in combination, it is necessary to change the load sharing rate of the refrigerator according to the situation. The load on each refrigerator is proportional to the flow rate of the heat medium. Therefore, in order to change the load sharing ratio to each refrigerator, the flow rate of the heat medium supplied to each refrigerator is adjusted by inverter control of the rotation speed of the pump provided in each primary return water pipe. There is a conventional technique corresponding to this (for example, refer to Patent Document 1).

  For example, in addition to the configuration shown in FIG. 3, in the heat source control system 60 shown in FIG. 4, the flow meters 91 and 92 that measure the flow rates of the primary return water pipes 71 and 72 and the primary pumps 73 and 74 are provided. Attached inverters 93 and 94, flow controllers 95 and 96 for controlling the inverters 93 and 94, and a flow distribution controller 97 for controlling the flow controllers 95 and 96 are provided.

  The flow distribution controller 97 calculates the load sharing ratio of each of the refrigerators 61 and 62 based on the amount of heat measured by the calorimeter 80 and transmits the corresponding set value to the flow controllers 95 and 96. Based on this, the flow controllers 95 and 96 give inverter inputs (indicated values of frequency) to the inverters 93 and 94 while taking into account the values of the flow meters 91 and 92, and control the rotational speeds of the primary pumps 73 and 74. To do.

Under the above configuration, when the load of the entire system is 60% operation (600 RT), ideally, the turbo chiller 61 having good operation efficiency at the time of rating is prioritized so that the operation is close to the rating. Then, a heat medium with a rated flow of 5040 (l / min) is sent to the turbo chiller 61, the turbo chiller 61 is operated at a rated load of 500 RT, and the remaining 1008 (l / min) with respect to the absorption chiller 62 It is preferable that the absorption refrigerator 62 is operated at a partial load of 100 RT. If this becomes possible, the load sharing ratio of the turbo refrigerator 61 and the absorption refrigerator 62 can be lowered to 5: 1.
JP 2007-292374 A

  However, each refrigerator 61, 62 has a minimum flow rate (generally 50%) that is the minimum required to prevent an abnormal stop due to freezing or the like and to operate stably. For this reason, regardless of the flow rate supplied to the air conditioner 67, it is always necessary to supply the heat medium exceeding the lower limit flow rate to the refrigerators 61 and 62 and the primary pumps 73 and 74.

  For example, in the heat source control system 60 shown in FIG. 4, when the lower limit flow rate of each of the refrigerators 61 and 62 is set to 50% of the rated flow rate, the turbo refrigerator 61 is used preferentially, and the absorption refrigerator 62 Even if the flow rate is controlled, the supply to the absorption chiller 62 must be maintained at least so as not to fall below the lower limit flow rate 2520 (l / min). For this reason, even if 5040 (l / min) of the rated flow is supplied to the turbo chiller 61, the load sharing ratio of both can only be reduced to 2: 1. As a result, the operating cost of the entire system increases.

  Note that the above-described problem is not limited to the configuration in which the turbo refrigerator and the absorption refrigerator are arranged in parallel, and even those of the same type (for example, a turbo refrigerator) having different characteristics (operation efficiency) are arranged in parallel. This can also occur in other configurations.

  The present invention has been made in view of the above circumstances, and an object thereof is to optimally distribute the load to each refrigerator according to the load condition applied to the air conditioner, and to operate the system with the optimum operation efficiency. An object of the present invention is to provide a heat source control system for an air-conditioning facility.

  In the following, each means suitable for solving the above-described problems will be described in terms of items. In addition, the effect etc. peculiar to the means to respond | correspond as needed are added.

Means 1. At least one unit is a heat source control system for air conditioning equipment in which a plurality of refrigerators having different characteristics are arranged in parallel,
A forward header that mixes the heat medium cooled and supplied by the evaporators of the plurality of refrigerators;
At least one air conditioner (heat exchanger) that receives supply of a heat medium from the forward header;
A return header through which the heat medium heat-exchanged in the air conditioner circulates;
A plurality of primary-side outgoing water pipes connecting the respective refrigerators and the outgoing header;
A plurality of primary-side return water pipes respectively connecting the return header and the refrigerators;
At least one secondary-side outgoing water pipe connecting the outgoing header and the air conditioner,
At least one secondary return water conduit connecting the air conditioner and the return header,
A plurality of pumps that are respectively provided in the respective primary-side return water pipes and capable of adjusting the flow rate of the heat medium supplied to the refrigerator;
A plurality of flow rate adjusting valves provided in each of the primary side outgoing water pipes and capable of adjusting the flow rate of the heat medium supplied to the outgoing header;
A plurality of bypass pipes each bypass-connecting a position upstream of the flow rate adjusting valve in the primary side outgoing water pipe relating to each of the refrigerators and a position upstream of the pump of the primary side return water pipe;
Heat medium in each of the primary side outgoing water line, the primary side return water line, and the bypass line provided for each of the refrigerators and corresponding to the pump and the flow rate adjustment valve. A plurality of flow rate control means for controlling the flow rate of
A flow distribution control means for controlling the plurality of flow control means and controlling the flow rate of the heat medium distributed from the return header to the primary return water pipes. Heat source control system.

  According to the above means 1, for each piping system corresponding to each refrigerator, a part of the heat medium before being cooled by the evaporator of the refrigerator and supplied to the forward header is passed through the bypass pipe to the primary side outgoing water pipe. It is configured to be able to return from the road to the primary return water pipe. Thereby, while ensuring the lower limit flow rate of the heat medium to be supplied to the predetermined refrigerator, the flow rate of the heat medium recirculated from the return header to the refrigerator (primary return water conduit) from the lower limit flow rate. Can also be reduced. As a result, when the load is shared among a plurality of refrigerators, the load sharing ratio for a predetermined refrigerator can be extremely reduced without considering the lower limit flow rate of the refrigerator.

  For example, when two refrigerators with different operating efficiencies (rated cooling capacity 500 RT) are operated simultaneously and the load on the air conditioner reaches 60% of the peak time (1000 RT) (600 RT), the operating efficiency is good. The coefficient of performance at the time of rating is relatively poor, such as when the refrigerator is preferentially operated at the maximum load (500RT) and the shortage (100RT) is compensated by the other refrigerator, but the overall efficiency at the partial load is too low The control which reduces the load concerning the refrigerator which does not fall extremely becomes possible.

  As a result, it is possible to optimally distribute the load to each refrigerator according to the load condition applied to the air conditioner, to operate the system with the optimum operation efficiency, and to increase the operation efficiency of the entire system. As a result, the increase in operating cost can be suppressed.

  The “different characteristics” refrigerators in the above means include not only refrigerators of different types such as turbo refrigerators and absorption refrigerators, but also refrigerators having the same model but different operating efficiency, etc. .

Mean 2. A secondary side heat medium pump is provided in the secondary side outgoing water line,
A secondary water temperature sensor is provided in the secondary water supply pipe, a return water temperature sensor and a secondary load flow meter are provided in the secondary water return pipe, and the measurement signal of each temperature sensor and the secondary side are provided. With a calorimeter that calculates the cooling load from the output signal of the load flow meter,
The heat source control system for an air conditioner according to claim 1, wherein a heat amount signal from the calorimeter is output to the flow rate distribution control means.

  According to the means 2, the flow rate in each pipeline can be adjusted more accurately, and the operational effect of the means 1 can be more reliably achieved.

Means 3. A plurality of flow meters that are provided in each of the primary return water pipes and that measure the flow rate of the heat medium returned from the return header to the primary return water pipes;
Each of the flow rate control means is configured so that the total flow rate of the flow rate of the heat medium returned from the return header to each primary return water pipe and the flow rate of the heat medium returned from each bypass pipe is from the pump. The heat source control system for an air conditioning facility according to the means 1 or 2, characterized by controlling so as not to fall below a lower limit of a flow rate sent to the refrigerator.

  According to the means 3, the flow rate in each pipe line can be adjusted more accurately, and the operational effects of the means 1 can be more reliably achieved.

Means 4. Each of the bypass pipes includes a second flow rate adjustment valve,
The flow rate control means proportionally controls the flow rate adjustment valve and the second flow rate adjustment valve, and controls the valve opening and closing operations of the flow rate adjustment valve and the second flow rate adjustment valve to be reversed. A heat source control system for air conditioning equipment according to any one of means 1 to 3.

  According to the means 4, the flow rate in each pipeline can be adjusted more accurately, and the operational effect of the means 1 can be more reliably achieved.

  Means 5. The heat source for an air conditioner according to any one of means 1 to 4, wherein the flow rate distribution control means distributes the load in preference to a refrigerator having good operating efficiency among the plurality of refrigerators. Control system.

  Means 6. The heat source control system for an air conditioning facility according to any one of means 1 to 5, wherein at least one of the plurality of refrigerators is a turbo refrigerator.

  The turbo chiller has a characteristic of high operating efficiency at the maximum load.

  Mean 7 The heat source control system for an air conditioner according to any one of means 1 to 6, wherein at least one of the plurality of refrigerators is an absorption refrigerator.

  The absorption refrigerator has a characteristic that the overall efficiency at the partial load does not decrease although the coefficient of performance COP at the rated time is relatively poor, that is, the operation efficiency at the partial load is high.

  Hereinafter, a heat source control system for air conditioning equipment in the present embodiment will be described with reference to the drawings. FIG. 1 shows the overall configuration of the heat source control system.

  As shown in FIG. 1, in the heat source control system 10, one turbo chiller 11 and one absorption chiller 12 are arranged in parallel. The turbo chiller 11 is an electric type for cooling only, and the absorption chiller 12 is a gas-fired type for producing cold / hot water and also used for cooling / heating. Both refrigerators 11 and 12 have a rated cooling capacity of 500 RT and a rated flow rate of 5040 (l / min), but have different coefficient of performance (COP), partial load characteristics, and the like. In addition, for both refrigerators 11 and 12, a minimum lower limit flow rate is set to prevent an abnormal stop due to freezing or the like and to operate stably. In the present embodiment, both the refrigerators 11 and 12 have a lower limit flow rate set to 2520 (l / min) which is 50% of the rated flow rate 5040 (l / min). Note that 1RT = 3024 [kcal / h], 1 [cal] = 4.186 [J].

  Each refrigerator 11 and 12 is connected to the forward header 15 via the primary side outgoing pipeline 13 and 14, respectively. The forward header 15 is connected to an air conditioner (heat exchanger) 17 through a secondary side outgoing water pipeline 16. The air conditioner 17 is connected to a return header 19 via a secondary side return water pipe 18. The return header 19 is connected to each of the refrigerators 11 and 12 via the primary-side return water pipes 21 and 22, respectively.

  The primary side return water pipes 21 and 22 are respectively provided with primary pumps 23 and 24 for pressure-feeding the heat medium to the refrigerators 11 and 12, respectively. The primary pumps 23 and 24 are respectively provided with inverters 23a and 24a, and the flow rate of the heat medium flowing to the refrigerators 11 and 12 can be arbitrarily adjusted.

  The forward header 15 includes a first header 15 a connected to the primary side outgoing pipelines 13, 14 and a second header 15 b connected to the secondary side outgoing pipeline 16. Between the headers 15a and 15b, secondary heat medium pumps 25a, 25b, and 25c for pressure-feeding the heat medium from the first header 15a to the air conditioner 17 are provided.

  In the secondary side outgoing water pipeline 16, an outgoing water temperature sensor 27 that measures the temperature (outgoing water temperature) of the heat medium supplied from the outgoing header 15 to the air conditioner 17 is provided. Similarly, the secondary side return water pipe 18 is provided with a return water temperature sensor 28 for measuring the temperature of the heat medium returned to the return header 19 (return water temperature).

  The return header 19 includes a first header 19 a connected to the secondary side return water pipe 18 and a second header 19 b connected to the primary side return water pipes 21 and 22. Between the headers 19a and 19b, a secondary load flow meter 29 for measuring the flow rate of the heat medium returned to the return header 19, that is, the flow rate of the heat medium supplied to the air conditioner 17, is provided.

  And the calorimeter 30 which calculates calorie | heat amount based on the information obtained from the going water temperature sensor 27, the return water temperature sensor 28, and the secondary side load flow meter 29 is provided.

  The secondary side return water pipe 18 is provided with a secondary side valve (flow rate adjusting valve) 31 for adjusting the flow rate of the heat medium supplied to the air conditioner 17 according to the load state.

  Further, a bypass pipe 35 is provided in parallel with the turbo chiller 11 between the primary side outgoing water line 13 and the primary side return water pipe 21 connected to the turbo chiller 11 to communicate the both. Yes. Similarly, between the primary side outgoing water line 14 and the primary side return water line 22 connected to the absorption refrigeration machine 12, a bypass pipe line 36 for communicating the two is in parallel with the absorption chiller 12. Is provided. The bypass pipes 35 and 36 are connected to the upstream side (return header 19 side) of the primary pumps 23 and 24 with respect to the primary return water pipes 21 and 22.

  The primary-side return water pipes 21 and 22 are provided with primary-side flow meters 41 and 42 for measuring the flow rate at the part upstream of the connection position of the bypass pipes 35 and 36. .

  Each primary-side outgoing water line 13, 14 has a first valve (flow rate adjusting valve) for adjusting the flow rate at that part on the downstream side (forward header 15 side) from the connection position of each bypass pipe line 35, 36. ) 45 and 46 are provided. Correspondingly, the bypass pipes 35 and 36 are provided with second valves (flow rate adjusting valves) 47 and 48 for adjusting the flow rate in the corresponding parts. The first valve 45 and the second valve 47 on the turbo side, and the first valve 46 and the second valve 48 on the absorption side are respectively proportionally controlled, and the valve opening / closing operation is reversed. For example, when the first valve 45 is fully opened, the second valve 47 is controlled to be fully closed.

  A flow rate controller 55 for controlling the first valve 45, the second valve 47, and the primary pump 23 (inverter 23a) is provided, and the first valve 46, the second valve 48, and the primary pump 24 (inverter) are provided. A flow rate controller 56 is provided for controlling 24a). Furthermore, a flow distribution controller 59 for controlling the flow controllers 55, 56 and the like is provided. The flow rate controllers 55 and 56 constitute flow rate control means in this embodiment, and the flow rate distribution controller 59 constitutes flow rate distribution control means.

  Under the above configuration, the heat medium generated by each of the refrigerators 11 and 12 is mixed in the forward header 15 and sent to the air conditioner 17. And after heat exchange with the air conditioner 17, it passes through the return header 19 and is sent to each refrigerator 11 and 12 again.

  When the air conditioner 17 is operated at a rated load of 1000 RT, the refrigerators 11 and 12 are also operated at a rated load of 500 RT. On the other hand, when the load on the air conditioner 17 is small, the secondary valve 31 is throttled to reduce the flow rate of the heat medium. In such a case, the heat source control system 10 performs control to distribute the load to the refrigerators 11 and 12.

  Hereinafter, the load distribution control procedure performed in the heat source control system 10 will be described with reference to the flowchart of FIG. Note that the processing of this flowchart is periodically repeated.

  First, in step S101, the calorimeter 30 obtains the water temperature obtained by the water temperature sensor 27 from T1, the water temperature obtained from the water temperature sensor 28 from T2, and the secondary load flow meter 29. Based on the calculated load flow rate Fx, the current load heat quantity Qx on the secondary side (air conditioner 17) is calculated from the following calculation formula (1).

Qx = Fx × (T2-T1) (1)
Next, in step S102, the flow distribution controller 59 determines whether or not the load heat quantity Qx is lower than the rated cooling capacity Q1 (500RT) of the turbo chiller 11.

  Here, when it is determined that the load heat quantity Qx is 500 RT or more, both the refrigerators 11 and 12 are put into an operation state in step S103.

  In subsequent step S104, the flow distribution controller 59 calculates the share of the absorption refrigeration machine 12, that is, the load heat quantity Q2 processed by the absorption refrigeration machine 12, based on the following arithmetic expression (2).

Q2 = Qx−Q1 (2)
In step S105, the flow rate distribution controller 59 distributes the load flow rate Fx based on the load heat amounts Q1 and Q2 shared by the refrigerators 11 and 12, that is, the flow rate that should flow at the positions of the primary flow meters 41 and 42. F1 and F2 are calculated. In such a case, the flow rate F1 is 5040 (l / min) which is the rated flow rate, and the flow rate F2 is calculated based on the following arithmetic expression (3).

F2 = Fx−F1 (3)
Based on this, the flow rate distribution controller 59 outputs the set values corresponding to the calculated flow rates F1 and F2 to the flow rate controllers 55 and 56 of the respective systems in steps S106 and S107, respectively. The controllers 55 and 56 perform setting processing related to this.

  Then, the flow rate controller 55 of the turbo side system controls the primary pump 23 with an inverter in step S <b> 108, and causes a heat medium of 5040 (l / min) to flow through the turbo chiller 11.

  On the other hand, the flow controller 56 of the absorption-type side system determines whether or not the flow rate F2 that should flow at a certain position of the primary side flow meter 42 is below the lower limit flow rate 2520 (l / min) in step S109. To do.

  Here, when it is determined that the flow rate F2 is equal to or greater than 2520 (l / min), the flow rate controller 56 performs inverter control on the primary pump 24 of the absorption side system in step S110, and the primary pump. 24, the flow rate F4 of the heat medium to be flowed is matched with the flow rate F2 to be flowed at a position of the primary flow meter 42, and in step S111, the first valve 46 of the absorption side system is fully opened. The control which makes 2 valve | bulb 48 fully closed is performed.

  If it is determined in step S109 that the flow rate F2 is lower than the lower limit flow rate 2520 (l / min), the flow rate controller 56 controls the primary pump 24 of the absorption side system by inverter control in step S112. Then, control is performed so that the flow rate F4 of the heat medium to be flowed by the primary pump 24 maintains the lower limit flow rate 2520 (l / min), and in step S113, the flow rate of the primary flow meter 42 is set to the flow rate F2. The first valve 46 of the absorption side system is throttled so that the second valve 48 is interlocked and opened so as to be inversely proportional thereto, and a predetermined flow rate in the bypass line 36 is ensured.

  If it is determined in step S102 that the load heat quantity Qx is less than the rated cooling capacity Q1 (500 RT) of the turbo chiller 11, the turbo chiller 11 is used preferentially, so in step S114. Only the turbo chiller 11 is brought into an operating state.

  In step S115, the flow rate distribution controller 59 calculates the flow rate F1 that should flow at a position of the primary side flow meter 41 of the primary side return pipe 21. Here, the flow rate F1 is matched with the load flow rate Fx.

  Based on this, the flow distribution controller 59 outputs a set value corresponding to the calculated flow F1 to the flow controller 55 of the turbo side system in step S116, and the flow controller 55 receiving this outputs the setting process related thereto. I do.

  Then, in step S117, the turbo flow rate controller 55 determines whether or not the flow rate F1 that should flow at a certain position of the primary flow meter 41 is below the lower limit flow rate of 2520 (l / min). .

  Here, when it is determined that the flow rate F1 is equal to or greater than 2520 (l / min), the flow rate controller 55 performs inverter control of the primary pump 23 of the turbo system in step S118, and the primary pump 23 The flow rate F3 of the heat medium to be caused to flow is matched with the flow rate F1 to be caused to flow at a position of the primary side flow meter 41, and in step S119, the first valve 45 of the turbo side system is fully opened, and the second valve Control is performed so that 47 is fully closed.

  If it is determined in step S117 that the flow rate F1 is below the lower limit flow rate 2520 (l / min), the flow rate controller 55 performs inverter control of the primary pump 23 of the turbo side system in step S120. Then, the flow rate F3 of the heat medium passed by the primary pump 23 is controlled to maintain the lower limit flow rate 2520 (l / min), and the flow rate of the primary flow meter 41 becomes the flow rate F1 in step S121. The first valve 45 of the turbo side system is throttled, and the second valve 47 is interlocked and opened so as to be inversely proportional thereto, so that a predetermined flow rate in the bypass line 35 is ensured.

  Under the above configuration, when the load of the entire system is, for example, 60% operation (600 RT), the turbo chiller 11 having good operation efficiency is preferentially used, and the rated flow rate 5040 ( l / min) of heat medium is sent, and the centrifugal chiller 11 is operated at 100% at a rated load of 500 RT. On the other hand, for the absorption refrigerator 12, the remaining heat medium of 1008 (l / min) from the return header 19 and the heat medium of 1512 (l / min) through the bypass pipe 36 are primarily used. The absorption refrigerator 12 is supplied to the side return water pipe 22 and the absorption refrigerator 12 is operated at a partial load of 100 RT while maintaining the flow rate of the heat medium supplied to the absorption refrigerator 12 at the lower limit flow rate 2520 (l / min). To do.

  Further, when the load of the entire system is further reduced, for example, when the operation is 20% (200 RT), only the turbo chiller 11 having good operation efficiency is set in the operation state. In such a case, a heat medium of 2016 (l / min) from the return header 19 to the turbo chiller 11 and a heat medium of 504 (l / min) through the bypass line 36 are supplied to the primary return water pipe 21. The turbo chiller 11 is set to 200 RT partial load operation while maintaining the flow rate of the heat medium supplied to the turbo chiller 11 at the lower limit flow rate 2520 (l / min).

  As described above in detail, in the present embodiment, for each piping system corresponding to each refrigerator 11, 12, a part of the heat medium generated by each refrigerator 11, 12 and supplied to the forward header 15 is obtained. The primary side outgoing water lines 13 and 14 can be returned to the primary side return water pipes 21 and 22 through the bypass pipes 35 and 36. Thus, while ensuring the lower limit flow rate 2520 (l / min) of the heat medium to be supplied to each of the refrigerators 11 and 12, it is returned to the refrigerators 11 and 12 (primary return water pipes 21 and 22). The flow rate of the heat medium returned from the header 19 can be reduced below the lower limit flow rate. As a result, when the load is shared to both the refrigerators 11 and 12, the load sharing rate for the predetermined refrigerators 11 and 12 can be extremely reduced without considering the lower limit flow rate of the refrigerators 11 and 12. It becomes possible.

  As a result, it is possible to optimally distribute the load to each of the refrigerators 11 and 12 according to the state of the load applied to the air conditioner 17, and to operate the system 10 with the optimum operation efficiency. Can be increased. As a result, the increase in operating cost can be suppressed.

  In addition, it is not limited to the description content of embodiment mentioned above, For example, you may implement as follows.

  (A) In the above embodiment, the heat source control system 10 in which one turbo refrigerator 11 and one absorption refrigerator 12 are arranged in parallel is described. However, the present invention is not limited to this, and may be applied to a heat source control system in which three or more refrigerators are arranged in parallel. Moreover, the number of the air conditioners 17 is not limited to one, and may be configured to include two or more.

  (B) The model of the refrigerator is not limited to the turbo refrigerator 11 or the absorption refrigerator 12, and other models such as an inverter turbo refrigerator may be adopted instead of or in addition to this. .

  (C) In the above-described embodiment, a configuration in which the turbo refrigerator 11 having high operation efficiency is preferentially used is shown. However, the configuration is not limited thereto, and an absorption refrigerator that operates using waste heat, for example, is installed. In this configuration, in order to make effective use of waste heat, operating costs can be reduced by using the absorption chiller preferentially.

  Moreover, it is good also as a structure which gives priority to the more economical one in consideration of electric power and fuel cost instead of giving priority to the one with good operation efficiency.

  (D) In the above embodiment, the first valve 45, 46 and the second valve 47, 48 are proportionally controlled to adjust the flow rate through each bypass pipe 35, 36. Not limited to this, for example, a three-way valve is arranged at the connection position of each primary side outgoing pipeline 13, 14 and each bypass pipeline 35, 36, thereby adjusting the flow rate through each bypass pipeline 35, 36. It is good also as a structure.

  (E) In the above embodiment, the load sharing of each of the refrigerators 11 and 12 is determined based on the load heat quantity Qx obtained from the calorimeter 30. However, the present invention is not limited to this. For example, from the secondary load flow meter 29 It may be calculated based on the obtained load flow rate Fx.

It is a block diagram of a heat source control system. It is a flowchart which shows the control procedure of load distribution. It is a block diagram of the heat source control system which concerns on a prior art. It is a block diagram of the heat source control system which concerns on a prior art.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 10 ... Heat source control system, 11 ... Turbo refrigerator, 12 ... Absorption-type refrigerator, 13, 14 ... Primary side outgoing pipe, 15 ... Outer header, 16 ... Secondary side outgoing pipeline, 17 ... Air conditioner, 18 ... secondary side return pipe, 19 ... return header, 21, 22 ... primary side return pipe, 23, 24 ... primary pump, 35, 36 ... bypass pipe, 41, 42 ... primary flow meter, 45, 46 ... first valve, 47, 48 ... second valve, 55, 56 ... flow rate controller, 59 ... flow rate distribution controller.

Claims (7)

At least one unit is a heat source control system for air conditioning equipment in which a plurality of refrigerators having different characteristics are arranged in parallel,
A forward header that mixes the heat medium cooled and supplied by the evaporators of the plurality of refrigerators;
At least one air conditioner that receives supply of a heat medium from the forward header;
A return header through which the heat medium heat-exchanged in the air conditioner circulates;
A plurality of primary-side outgoing water pipes connecting the respective refrigerators and the outgoing header;
A plurality of primary-side return water pipes respectively connecting the return header and the refrigerators;
At least one secondary-side outgoing water pipe connecting the outgoing header and the air conditioner,
At least one secondary return water conduit connecting the air conditioner and the return header,
A plurality of pumps that are respectively provided in the respective primary-side return water pipes and capable of adjusting the flow rate of the heat medium supplied to the refrigerator;
A plurality of flow rate adjusting valves provided in each of the primary side outgoing water pipes and capable of adjusting the flow rate of the heat medium supplied to the outgoing header;
A plurality of bypass pipes each bypass-connecting a position upstream of the flow rate adjusting valve in the primary side outgoing water pipe relating to each of the refrigerators and a position upstream of the pump of the primary side return water pipe;
Heat medium in each of the primary side outgoing water line, the primary side return water line, and the bypass line provided for each of the refrigerators and corresponding to the pump and the flow rate adjustment valve. A plurality of flow rate control means for controlling the flow rate of
A flow distribution control means for controlling the plurality of flow rate control means and controlling the flow rate of the heat medium distributed from the return header to each primary return water pipe. Heat source control system. A secondary side heat medium pump is provided in the secondary side outgoing water line,
A secondary water temperature sensor is provided in the secondary water supply pipe, a return water temperature sensor and a secondary load flow meter are provided in the secondary water return pipe, and the measurement signal of each temperature sensor and the secondary side are provided. With a calorimeter that calculates the cooling load from the output signal of the load flow meter,
The heat source control system for an air conditioner according to claim 1, wherein a heat amount signal from the calorimeter is output to the flow rate distribution control means. A plurality of flow meters that are provided in each of the primary return water pipes and that measure the flow rate of the heat medium returned from the return header to the primary return water pipes;
Each of the flow rate control means is configured so that the total flow rate of the flow rate of the heat medium returned from the return header to each primary return water pipe and the flow rate of the heat medium returned from each bypass pipe is from the pump. The heat source control system for an air conditioner according to claim 1 or 2, wherein control is performed so as not to fall below a lower limit of a flow rate sent to the refrigerator. Each of the bypass pipes includes a second flow rate adjustment valve,
The flow rate control means proportionally controls the flow rate adjustment valve and the second flow rate adjustment valve, and controls the valve opening and closing operations of the flow rate adjustment valve and the second flow rate adjustment valve to be reversed. The heat source control system for an air conditioner according to any one of claims 1 to 3.   5. The air conditioning equipment according to claim 1, wherein the flow distribution control unit distributes a load in preference to a refrigerator having a high operation efficiency among the plurality of refrigerators. Heat source control system.   The heat source control system for an air conditioner according to any one of claims 1 to 5, wherein at least one of the plurality of refrigerators is a turbo refrigerator.   The heat source control system for an air conditioning facility according to any one of claims 1 to 6, wherein at least one of the plurality of refrigerators is an absorption refrigerator.

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