JP2016205814A - Load distribution system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a load distribution system that can suppress degradation of energy efficiency of a whole system.SOLUTION: A load distribution system includes a first heat source machine (first refrigerator 51), a second heat source machine (second refrigerator 52/third refrigerator 53) disposed in parallel to the first heat source machine, secondary side equipment 20, and a heat medium circulation circuit 70. The first heat source machine is the heat source machine having a variable speed compressor. The second heat source machine is the heat source machine having a constant speed compressor or an absorber type heat source machine. The heat medium circulation circuit 70 is provided with: a pump 40 being common to the first heat source machine and the second heat source machine, and circulating the heat medium to the heat medium circulation circuit 70; a first flow regulating valve (61) for regulating a flow rate of the heat medium flowing from the pump 40 to the first heat source machine; and second flow regulating valves (62/63) for regulating the flow rate of the heat medium flowing from the pump 40 to the second heat source machine. The pump 40 is one for the first heat source machine and the second heat source machine.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a load distribution system.

  Conventionally, a heat source device having a variable speed compressor and a heat source device having a constant speed compressor or an absorption heat source device are arranged in parallel, and each heat source device is driven according to a load required from the use side equipment. There is a system to control. Here, it is known that the operation efficiency when the heat source machine or the absorption heat source machine having the constant speed compressor is driven with the rated capacity is much better than the heat source machine having the variable speed compressor. On the other hand, at the time of partial load, the operation efficiency of the heat source machine or the absorption heat source machine having the constant speed compressor is lower than that of the heat source machine having the variable speed compressor because the operation efficiency is lowered. Therefore, when using each heat source unit in combination, as a conventional technique for improving the energy efficiency of the entire system by changing the distribution of the load to each heat source unit according to the load required from the use side equipment For example, there exists patent document 1 (Unexamined-Japanese-Patent No. 2007-292374). In the system described in Patent Document 1, the discharge capacity is adjusted as a pump for flowing the heat medium to the heat source machine by utilizing the property that the load of each heat source machine is proportional to the flow rate of the heat medium to each heat source machine. The inverter pump that can be used is adopted. And the flow volume of the heat medium to each heat source machine is adjusted by controlling the discharge capacity of each inverter pump. Thereby, in the system of patent documents 1, distribution of load to each heat source machine is changed.

  However, in the system described in Patent Document 1, when a control command that greatly varies the discharge capacity is given to each inverter pump, the control command is received so that the discharge capacity is reduced due to the pressure between the pumps. In addition, the heat medium may be difficult to flow through the inverter pump. If it does so, only the heat medium of the quantity less than a desired flow volume will flow into the heat source machine into which a heat medium flows from this inverter pump. As described above, in the system described in Patent Document 1, when setting the flow rate of the heat medium for each heat source device, it is not possible to make a large difference in the flow rate of the heat medium distributed to each heat source device. In this case, the desired load distribution cannot be performed, and as a result, the energy efficiency of the entire system may be deteriorated.

  Then, the subject of this invention is setting the flow volume of the heat medium distributed with respect to each of the heat source machine which has a variable speed compressor, the heat source machine which has a constant speed compressor, or an absorption heat source machine, An object of the present invention is to provide a load distribution system capable of suppressing deterioration of energy efficiency of the entire system.

  The load distribution system concerning the 1st viewpoint of the present invention is provided with the 1st heat source machine, the 2nd heat source machine, the use side equipment, and the heat carrier circulation circuit. The first heat source machine heats or cools the heat medium. The second heat source machine heats or cools the heat medium. The 2nd heat source machine is arranged in parallel with the 1st heat source machine. The use side facility is supplied with a heat medium from the first heat source device and the second heat source device. In the heat medium circulation circuit, the first heat source device, the second heat source device, and the use side equipment are connected. The first heat source machine is a heat source machine having a variable speed compressor. The second heat source machine is a heat source machine having a constant speed compressor or an absorption heat source machine. The heat medium circulation circuit is provided with a pump, a first flow rate adjustment valve, and a second flow rate adjustment valve. The pump is for circulating the heat medium in the heat medium circulation circuit. The pump is common to the first heat source machine and the second heat source machine. The first flow rate adjusting valve is for adjusting the flow rate of the heat medium flowing from the pump to the first heat source unit. The second flow rate adjusting valve is for adjusting the flow rate of the heat medium flowing from the pump to the second heat source machine. There is one pump for the first heat source machine and the second heat source machine.

  In the load distribution system according to the first aspect of the present invention, the heat medium flows to the first heat source unit and the second heat source unit by one common pump, and the first flow rate adjustment valve and the second flow rate adjustment valve change the first heat source unit. The flow rate of the heat medium to the first heat source machine and the second heat source machine is adjusted. For this reason, the heat medium flows from a pump with a variable discharge capacity for each heat source unit, and the flow rate of the heat medium to each heat source unit is adjusted by each pump rather than each pump. When flowing the heat medium, a large difference can be made in the flow rate. Therefore, the flow rate of the heat medium distributed to each heat source machine can be set appropriately.

  Thereby, the deterioration of the energy efficiency of the whole system can be suppressed.

  A load distribution system according to a second aspect of the present invention includes a control unit in the load distribution system according to the first aspect. A control part controls the drive number of a 1st heat-source machine and a 2nd heat-source machine according to the load requested | required from a utilization side installation. When the load required from the use side equipment is gradually increased and a load higher than the load that can be handled by the first heat source machine is requested, the control unit causes the heat medium to flow to the second heat source machine. The opening degree of the second flow rate adjustment valve is adjusted, and the opening degree of the first flow rate adjustment valve is adjusted so that the first heat source device is driven with the minimum capacity. For this reason, in this load distribution system, when both the first heat source machine and the second heat source machine are driven, the flow rate of the heat medium to the first heat source machine and the second heat source machine is the same as that of the entire system. Energy loss can be suppressed.

  The load distribution system according to a third aspect of the present invention is the load distribution system according to the second aspect, wherein the number of first heat source units is two or more. The total capacity of the first heat source machine is equal to or less than the rated capacity of the second heat source machine. For this reason, when it comes to the situation where the 2nd heat source machine is driven in addition to the 1st heat source machine, the energy loss of the whole system can be suppressed by adjusting the flow rate of the heat medium to each first heat source machine. .

  In the load distribution system according to the fourth aspect of the present invention, in any one of the load distribution systems according to the first to third aspects, the pump is a metering pump having a constant heat medium discharge capacity per unit time. For this reason, in this load distribution system, cost can be suppressed compared with the case where a pump with variable discharge capacity is adopted.

  The load distribution system according to a fifth aspect of the present invention is the load distribution system according to any one of the first to fourth aspects, wherein the second flow rate adjustment valve allows or blocks the flow of the heat medium to the second heat source unit. This is an open / close valve. For this reason, in this load distribution system, cost can be suppressed compared with the case where the valve which can change a flow rate at the time of permission is adopted as the 2nd flow control valve.

  In the load distribution system according to the first aspect of the present invention, deterioration of energy efficiency of the entire system can be suppressed.

  In the load distribution system according to the second aspect of the present invention, energy loss of the entire system can be suppressed.

  In the load distribution system according to the third aspect of the present invention, energy loss of the entire system can be suppressed.

  In the load distribution system according to the fourth aspect of the present invention, the cost can be suppressed.

  In the load distribution system according to the fifth aspect of the present invention, the cost can be suppressed.

1 is a schematic configuration diagram of a load distribution system according to an embodiment of the present invention. The control block diagram of the control apparatus with which a load distribution system is provided. The figure which shows the flow of the refrigerator number control by a chiller system controller. The schematic block diagram of the primary side equipment with which the load distribution system as a prior art is provided. The figure for demonstrating each energy loss of the load distribution system which concerns on this embodiment, and the load distribution system as a prior art. The schematic block diagram of the primary side equipment with which the load distribution system which concerns on the modification A is provided. The figure for demonstrating each energy loss of the load distribution system which concerns on the modification A, and the load distribution system as a prior art.

  Hereinafter, a load distribution system according to an embodiment of the present invention will be described with reference to the drawings. The following embodiments are specific examples of the present invention and do not limit the technical scope of the present invention.

(1) Overall Configuration of Load Distribution System FIG. 1 is a schematic configuration diagram of a load distribution system according to an embodiment of the present invention. The load distribution system according to the present embodiment can suppress deterioration in energy efficiency of the entire system. Load distribution systems are mainly installed in relatively large buildings such as buildings, factories, hospitals, and hotels.

  As shown in FIG. 1, the load distribution system includes a heating medium between a primary side equipment 10 as a heat source side equipment and a secondary side equipment 20 as a usage side equipment via a pipe connecting the both 10 and 20. As a system to circulate water.

  The primary side equipment 10 mainly includes first to third refrigerators 51 to 53 serving as heat source units for heating or cooling the heat medium, and first to third units provided corresponding to the first to third refrigerators 51 to 53. The 3rd flow regulating valves 61-63 and the pump 40 common to the 1st-3rd refrigerator 51-53 are included.

  In addition, the 1st refrigerator 51 of this embodiment is a heat source machine which has a variable speed compressor. The variable speed compressor is a compressor capable of changing the rotation speed. The first refrigerator 51 is a variable capacity type heat source device that can be operated by adjusting the capacity (refrigeration capacity) by switching the rotation speed of the compressor. The 2nd refrigerator 52 and the 3rd refrigerator 53 are heat source machines which have a constant speed compressor. A constant speed compressor is a compressor in which the rotational speed of the compressor is constant. By the way, in this embodiment, although the 2nd refrigerator 52 and the 3rd refrigerator 53 are heat source machines which have a constant speed compressor, the 2nd refrigerator 52 and the 3rd refrigerator 53 are absorption type heat source machines. May be. The absorption heat source machine is a heat source machine that does not include a compressor and has a constant capacity. That is, the 2nd freezer 52 and the 3rd freezer 53 are constant capacity type heat source machines.

  The secondary side equipment 20 mainly includes first to ninth air conditioners 21 to 29 which are heat utilization devices installed in each air conditioning target space (hereinafter referred to as indoor space) in a building. Then, cold water flows during cooling, warm water flows from the primary side equipment 10 to the secondary side equipment 20 during heating, and the first to ninth air conditioners 21 to 29 during which the cold or warm water is operating the secondary side equipment 20. Used for air conditioning.

  The primary equipment 10 is controlled by a chiller system controller 110 and the secondary equipment 20 is controlled by an air conditioner controller 120.

(2) Detailed configuration of load distribution system (2-1) Heat medium circulation circuit 70
The heat medium circulation circuit 70 is a closed circuit filled with water, and is configured such that water circulates between the first to third refrigerators 51 to 53 and the first to ninth air conditioners 21 to 29. ing. In the heat medium circulation circuit 70, the pump 40, the first to third flow rate adjusting valves 61 to 63, the first to third refrigerators 51 to 53, the forward header 11, and the first to ninth air conditioners 21 are provided. To 29 and the return header 12 are connected.

  As shown in FIG. 1, the heat medium circulation circuit 70 includes a secondary pipe 71, a first common pipe 72, a second common pipe 73, first to third pipes 74 to 76, and a bypass pipe 77. Have. The secondary side pipe 71 connects the forward header 11 and the return header 12 so that water flows through each of the first to ninth air conditioners 21 to 29. The first common pipe 72 is connected to the return header 12. The second common pipe 73 is connected to the forward header 11. The first to third pipes 74 to 76 are pipes that connect the first common pipe 72 and the second common pipe 73. More specifically, the first to third pipes 74 to 76 are arranged in parallel so as to connect the branch point P1 located at the end of the first common pipe 72 and the branch point P2 located at the end of the second common pipe 73. It is the piping provided in. The bypass pipe 77 connects the return header 12 and the forward header 11.

(2-2) Primary side equipment 10
In the primary side equipment 10, the three first to third refrigerators 51 to 53 serve as heat sources in the load distribution system. Each of the first to third refrigerators 51 to 53 is provided with one each of the first to third flow rate adjusting valves 61 to 63. One pump 40 is provided for the first to third refrigerators 51 to 53. The first to third refrigerators 51 to 53 are connected in parallel to each other as shown in FIG. Specifically, the first common pipe 72 is provided with the pump 40, the first pipe 74 is provided with the first flow rate adjustment valve 61 and the first refrigerator 51, and the second pipe 75 is provided with the second flow rate adjustment. A valve 62 and a second refrigerator 52 are provided, and a third flow rate adjusting valve 63 and a third refrigerator 53 are provided in the third pipe 76.

  The first to third refrigerators 51 to 53 are air-cooled heat pump chillers, and a compressor, an air-side heat exchanger, an expansion valve, and a water-side heat exchanger are sequentially connected to form a refrigerant circuit, and the refrigerant circuit Is filled with a refrigerant. As described above, the first refrigerator 51 is equipped with one or a plurality of variable speed compressors, and in this embodiment, the variable speed compressor is an inverter compressor whose capacity can be adjusted. As described above, the second and third refrigerators 53 are equipped with one or a plurality of constant speed compressors. In this embodiment, the constant speed compressors are compressors whose capacity cannot be adjusted. Instead of the constant speed compressor of this embodiment, a compressor whose capacity can be adjusted by hot gas bypass may be used.

  The first to third flow rate adjusting valves 61 to 63 are valves for adjusting the amount of water flowing to the first to third refrigerators 51 to 53, respectively. The first flow rate adjusting valve 61 is for adjusting the flow rate of the heat medium flowing from the pump 40 to the first refrigerator 51. The first flow rate adjustment valve 61 of the present embodiment can allow or block the flow of water to the first refrigerator 51, and can change the flow rate of water flowing to the first refrigerator 51 when allowed. . The second flow rate adjustment valve 62 is for adjusting the flow rate of the heat medium flowing from the pump 40 to the second refrigerator 52. The second flow rate adjustment valve 62 of the present embodiment is an on-off valve that allows or blocks the flow of water to the second refrigerator 52, and changes the flow rate of water flowing to the second refrigerator 52 when allowed. I can't. The third flow rate adjusting valve 63 is for adjusting the flow rate of the heat medium flowing from the pump 40 to the third refrigerator 53. The third flow rate adjustment valve 63 of the present embodiment is an on-off valve that allows or blocks the flow of water to the third refrigerator 53, and to the third refrigerator 53 when allowed, like the second flow rate adjustment valve 62. And the flow rate of flowing water cannot be changed. It should be noted that the flow rate adjustment valve employed as the second flow rate adjustment valve 62 and the third flow rate adjustment valve 63 can change the flow rate of water flowing to the refrigerator when the same configuration as the first flow rate adjustment valve 61 is allowed. It may be possible.

  The pump 40 plays a role of circulating water in the heat medium circulation circuit 70. The pump 40 of this embodiment is a constant speed pump in which the discharge amount of water per unit time is constant, and the start / stop is controlled by the chiller system controller 110. The employed pump 40 is not limited to a constant speed pump, and may be a variable displacement pump that is inverter-driven by the chiller system controller 110.

  In the primary side equipment 10, when the pump 40 is driven, water (cold water or hot water) sent from the first to third refrigerators 51 to 53 is secondary through the second common pipe 73 and the forward header 11. It flows to the side pipe 71. Further, the water returned from the secondary side equipment 20 via the secondary side pipe 71 once flows into the return header 12 and then passes through the first common pipe 72 to the first to third refrigerators 51 to 53. Flowing.

  In addition, a bypass flow rate adjusting valve 77a is provided in the bypass pipe 13 connecting the forward header 11 and the return header 12. By changing the opening of the bypass flow rate control valve 77a and adjusting the flow rate of water that returns directly from the forward header 11 to the return header 12 through the bypass pipe 13, the flow rate of water flowing to the secondary equipment 20 is suppressed. be able to.

(2-3) Secondary side equipment 20
The secondary-side facility 20 has nine first to ninth air conditioners 21 to 29 as heat utilization devices. Each of the first to ninth air conditioners 21 to 29 uses the cold water of the cold water or the hot water generated by the first to third refrigerators 51 to 53 of the primary-side facility 10 that is a heat source device, respectively, Handle the load. That is, the first to ninth air conditioners 21 to 29 perform air conditioning (cooling or heating) of the indoor space using cold water or hot water flowing from the primary side equipment 10.

  The first to ninth air conditioners 21 to 29 are installed in the same or different indoor spaces. Each of the first to ninth air conditioners 21 to 29 is arranged in parallel between the secondary side pipe 71 extending from the forward header 11 and the secondary side pipe 71 connected to the return header 12. The first to ninth air conditioners 21 to 29 take water from the secondary pipe 71 on the forward header 11 side and return the water to the secondary pipe 71 on the return header 12 side.

  Air passages through which air flows are formed in the respective casings of the first to ninth air conditioners 21 to 29. One end of a suction duct (not shown) is connected to the inflow end of the air passage, and one end of an air supply duct (not shown) is connected to the outflow end of the air passage. The other ends of the suction duct and the air supply duct are each connected to the indoor space.

  Inside each casing of the first to ninth air conditioners 21 to 29, a blower fan, a heat exchanger, a flow rate adjusting valve, and the like are arranged. The heat exchanger causes heat exchange between water and air to cool or heat the air. As the heat exchanger, for example, a fin-and-tube heat exchanger having a plurality of heat transfer fins and a heat transfer tube penetrating the heat transfer fins is employed. In the heat transfer tube of the heat exchanger, water circulating between the primary side equipment 10 and the secondary side equipment 20 flows, and the heat of the water is supplied to the air via the heat transfer pipe and the heat transfer fins. The air is cooled or heated. The blower fan can change the rotational speed stepwise by inverter control, and can adjust the blown amount of heated or cooled air. The flow rate adjusting valve plays a role of adjusting the amount of water flowing to the air conditioner. That is, the flow rate of water flowing through each of the first to ninth air conditioners 21 to 29 is determined by the opening degree of each flow rate adjustment valve. Each blower fan and each flow rate adjustment valve are controlled by the air conditioner controller 120.

(2-4) Control Device FIG. 2 is a control block diagram of a control device provided in the load distribution system. The control device mainly includes a chiller system controller 110 and an air conditioner controller 120. As described above, the chiller system controller 110 controls the first to third refrigerators 51 to 53, the first to third flow rate adjusting valves 61 to 63, and the pump 40, and the air conditioner controller 120 controls the first to ninth air conditioners. Control machines 21-29.

  The detailed configuration related to the startup control of the chiller system controller 110 will be described in detail below.

(3) Operation of the load distribution system (3-1) Overall schematic operation In each of the first to ninth air conditioners 21 to 29, the indoor air taken in from the indoor space by the suction duct (not shown) Flow through air passage. This air is cooled / heated by cold water / hot water flowing from the primary side equipment 10 in each heat exchanger or the like. The cooled / heated air is supplied to the indoor space via an air supply duct (not shown), thereby cooling / heating the indoor space.

(3-2) Start-up Control by Chiller System Controller 110 The chiller system controller 110 mainly includes a CPU 180 and a memory 190. The memory 190 includes a ROM and a RAM, and various programs and the like that are read and executed by the CPU 180 are stored in the ROM. The RAM functions as a work memory for the CPU 180 and stores information that can be rewritten by the CPU 180.

  The chiller system controller 110 can change the number of operating refrigerators according to the load on the secondary equipment 20 (specifically, the thermal load of each indoor space to be processed by the first to ninth air conditioners 21 to 29). Control of the number of refrigerators to be performed is performed as control relating to the first to third refrigerators 51 to 53.

(3-3) Control of the number of refrigerators Next, functions related to the control of the number of refrigerators of the chiller system controller 110 will be described in detail.

  As shown in FIG. 2, the CPU 180 that executes the program read from the ROM includes a secondary load amount calculation unit 181 and a refrigerator number determination unit 182 as functional units on the software related to activation control. Will be provided. The memory 190 stores a refrigerator characteristic table 191. In the refrigerator characteristic table 191, information relating to the types of first to third refrigerators 51 to 53 (variable capacity type, constant capacity type, etc.), compressor capacity, operating efficiency, and the like is created and input in advance.

  The secondary load amount calculation unit 181 calculates a load required by the secondary equipment 20. For example, the secondary load amount calculation unit 181 measures the measured value of the outgoing water temperature sensor 111 that measures the temperature of the water flowing from the primary side equipment 10 to the secondary side equipment 20 every predetermined time, and the secondary side equipment 20. Air conditioner that the secondary side equipment 20 is operating on the basis of the measured value of the return water temperature sensor 112 that measures the temperature of the water flowing from the primary side equipment 10 to the primary side equipment 10 and the amount of circulating water measured by the water quantity sensor 113. The load of the machine, that is, the load required by the secondary equipment 20 (hereinafter referred to as the required load amount) is calculated.

  The refrigerator number determining unit 182 determines the number and capacity of the refrigerators to be operated so that the required load amount calculated by the secondary load amount calculating unit 181 is processed. And the refrigerator number determination part 182 adjusts the valve opening degree of the 1st-3rd refrigerator 51-53 and the 1st-3rd flow control valve 61-63 according to the determined number and capacity of the refrigerator. To do. In other words, the refrigerator number determining unit 182 has a role as a functional unit for reviewing the refrigerator to be operated from the start control to the end of the start control. Specifically, the refrigerator number determining unit 182 reviews one or a plurality of refrigerators that are already in operation every predetermined time. More specifically, the number-of-refrigerating machine determination unit 182 determines the primary side determined last time when a predetermined time has elapsed based on the measured / estimated load of the secondary equipment 20 while the start-up control is being executed. The operation number and capacity of the refrigerator of the facility 10 are corrected.

  Here, using the refrigerator characteristic table 191 stored in the memory 190, the refrigerator number determining unit 182 determines the number and capacity of the refrigerators to be operated. The number of refrigerators determination unit 182 determines the number and capacity (load) of refrigerators by selecting an appropriate combination from the operation combinations of the first to third refrigerators 51 to 53 according to the required load amount. To do.

  For example, when the load required from the secondary-side equipment 20 is small, that is, when the required load amount can be processed by operating only the first refrigerator 51, the number-of-freezer determining unit 182 It is determined that only the refrigerator 51 is operated. And when the load requested | required from the secondary side equipment 20 increases gradually and the load more than the load which can be coped with by the 1st freezer 51 is requested | required, ie, only the 1st freezer 51 is operated, a required load When the amount cannot be processed and it is necessary to operate the second refrigerator 52 in addition to the first refrigerator 51, a determination is made to operate the second refrigerator 52 in addition to the first refrigerator 51. When starting the operation (drive) of the second refrigerator 52, the refrigerator number determining unit 182 determines the capacity of the first refrigerator 51 to the minimum capacity (the lower limit capacity at which the compressor does not stop due to thermo-off). Then, the first refrigerator 51 is operated with the minimum capacity. After that, when the load required from the secondary side equipment 20 is gradually increased and a load more than the load that can be handled by the first refrigerator 51 and the second refrigerator 52 is required, that is, the first refrigerator 51 and If the required load cannot be processed even if the second refrigerator 52 is operated, and the third refrigerator 53 needs to be operated in addition to the first refrigerator 51 and the second refrigerator 52, the first refrigerator It is determined that the third refrigerator 53 is operated in addition to the machine 51 and the second refrigerator 52. When starting the operation (drive) of the third refrigerator 53, the refrigerator number determining unit 182 determines the capacity of the first refrigerator 51 as the minimum capacity and operates the first refrigerator 51 with the minimum capacity. Let On the other hand, when the 1st-3rd refrigerator 51-53 is driving | operating, the load requested | required from the secondary side equipment 20 reduces gradually, and the 1st refrigerator 51 and the 2nd refrigerator 52 are operated. When the required load amount can be processed, the number-of-freezer determining unit 182 determines to stop the operation of the third refrigerator 53 and operate the first refrigerator 51 and the second refrigerator 52. I do. Moreover, when the 1st freezer 51 and the 2nd freezer 52 are driving | operating, the load requested | required from the secondary side equipment 20 reduces gradually, and a required load is made to drive only the 1st freezer 51. When the amount can be processed, the refrigerator number determining unit 182 determines to stop the operation of the second refrigerator 52 and operate only the first refrigerator 51.

(3-4) Flow of refrigerator number control With reference to FIG. 3, each step of the refrigerator number control by the chiller system controller 110 is demonstrated. In the following description, 100% capacity of each refrigerator means the rated capacity of each refrigerator, and the minimum capacity of the first refrigerator 51 is 15%.

  In the control of the number of refrigerators, as described above, the secondary side load amount calculation unit 181 calculates the load of the secondary side equipment 20 based on the temperature of the outgoing water, the temperature of the circulating water, and the amount of water, and based on that. The refrigerator number determining unit 182 determines the number and capacity of refrigerators to be operated.

  First, in step S11, it is determined that the first refrigerator 51 is operated, and only the first refrigerator 51 is operated. Specifically, the opening degree of the first flow rate adjustment valve 61 is adjusted so that the water temperature on the outlet side of the first refrigerator 51 becomes the set temperature, and the variable speed compressor is set with a predetermined capacity (inverter output). Drive. Then, the process proceeds to step S12.

  In step S12, the secondary load amount calculation unit 181 and the refrigerator number determination unit 182 determine whether or not the capacity of the first refrigerator 51 has reached 100%. Then, when it is determined in step S12 that the capacity of the first refrigerator 51 has reached 100%, the process proceeds to step S13. On the other hand, if it is determined in step S12 that the capacity of the first refrigerator 51 has not reached 100%, the process returns to step S12.

  In step S13, the refrigerator number determining unit 182 determines the start of operation of the second refrigerator 52 in addition to the first refrigerator 51, and proceeds to step S14. In step S14, when the capacity of the first refrigerator 51 is not fixed at the minimum capacity (here, 15%), the capacity of the first refrigerator 51 is fixed to 15%, and the first refrigerator 51 The valve opening degree of the first flow rate adjusting valve 61 is adjusted so that the water temperature on the outlet side becomes the set temperature. Further, when the operation of the second refrigerator 52 is not started, in order to start the operation of the second refrigerator 52, the compressor of the second refrigerator 52 is started and the second flow rate is set. The adjustment valve 62 is opened. As a result, the first refrigerator 51 and the second refrigerator 52 are operated, and an amount of water necessary for exhibiting the minimum capacity flows through the first refrigerator 51, and the remaining water flows to the second. It will flow to the refrigerator 52. Then, the process proceeds to step S15.

  In step S15, the secondary load amount calculation unit 181 and the refrigerator number determination unit 182 determine whether or not the capacity of the second refrigerator 52 has reached 100%. If it is determined in step S15 that the capacity of the second refrigerator 52 has reached 100%, if the capacity of the first refrigerator 51 is not released, the first refrigerator 51 is determined in step S16. And the opening degree of the first flow rate adjusting valve 61 is adjusted so that the capacity of the second refrigerator 52 is maintained at 100%. Thereafter, the process proceeds to step S19. On the other hand, if it is determined in step S15 that the capacity of the second refrigerator 52 has not reached 100%, in step S17, the capacity of the second refrigerator 52 continues for a certain time or more and is less than 85%. Judge whether or not. If it is determined in step S17 that the capacity of the second refrigerator 52 continues to be less than 85% for a predetermined time or longer, the refrigerator in which the refrigerator number determining unit 182 is operated is determined as the first refrigerator in step S18. The refrigerator 51 is determined, that is, the second refrigerator 52 is determined to be reduced, and the first refrigerator 51 is operated with a predetermined capacity and the operation of the second refrigerator 52 is stopped. As a result, only the first refrigerator 51 is operated. Then, it returns to step S12. On the other hand, if it is determined in step S17 that the capacity of the second refrigerator 52 continues for a certain time or more and is not less than 85%, the process returns to step S14.

  In step S19, the secondary load amount calculating unit 181 and the refrigerator number determining unit 182 determine whether or not the capacities of the first refrigerator 51 and the second refrigerator 52 have reached 100%. When it is determined in step S19 that the capacities of the first refrigerator 51 and the second refrigerator 52 have reached 100%, the process proceeds to step S20. On the other hand, if it is determined in step S19 that the capacities of the first refrigerator 51 and the second refrigerator 52 have not reached 100%, the process returns to step S17.

  In step S20, the refrigerator number determining unit 182 determines the start of operation of the third refrigerator 53 in addition to the first refrigerator 51 and the second refrigerator 52, and the capacity of the first refrigerator 51 is fixed at 15%. If not, in step S21, the capacity of the first refrigerator 51 is fixed to 15%, and the valve of the first flow rate adjustment valve 61 is set so that the water temperature on the outlet side of the first refrigerator 51 becomes the set temperature. Adjust the opening. Further, when the operation of the third refrigerator 53 is not started, in order to start the operation of the third refrigerator 53, the driving of the compressor included in the third refrigerator 53 is started and the third flow rate is set. The adjustment valve 63 is opened. As a result, the first to third refrigerators 51 to 53 are operated, and the first refrigerator 51 is supplied with an amount of water necessary for exhibiting the minimum capacity, and the remaining water is supplied to the second refrigerator. It will flow equally to the machine 52 and the third refrigerator 53. Then, the process proceeds to step S22.

  In step S22, the secondary load amount calculation unit 181 and the refrigerator number determination unit 182 determine whether the respective capacities of the second refrigerator 53 and the third refrigerator 53 have reached 100%. If it is determined in step S22 that the capacities of the second refrigerator 52 and the third refrigerator 53 have reached 100%, if the capacity fixing of the first refrigerator 51 has not been released, in step S23 In addition to releasing the fixed capacity of the first refrigerator 51, the valve opening of the first flow rate adjusting valve 61 is adjusted so that the capacities of the second refrigerator 52 and the third refrigerator 53 are maintained at 100%. Return to S22. On the other hand, when it is determined in step S22 that the capacities of the second refrigerator 52 and the third refrigerator 53 have not reached 100%, in step S24, the capacities of the third refrigerator 53 continue for a certain time or more. It is judged whether it is less than 92.5%. If it is determined in step S24 that the capacity of the third refrigerator 53 continues for a certain time or more and is less than 92.5%, the refrigerator in which the refrigerator number determining unit 182 is operated in step S25. The first refrigerator 51 and the second refrigerator 52 are determined, that is, it is determined to reduce the third refrigerator 53, and the process returns to step S16. As a result, the first refrigerator 51 and the second refrigerator 52 are operated, and the operation of the third refrigerator 53 is stopped. On the other hand, if it is determined in step S24 that the capacity of the third refrigerator 53 continues for a certain time or more and is not less than 92.5%, the process returns to step S21.

(4) Features (4-1)
Here, water flows from a pump capable of discharging capacity to each of the first heat source machine and the second heat source machine, and the flow rate of water to the first heat source machine and the second heat source machine is adjusted by each pump. When a control command that greatly varies the discharge capacity is given to each pump, water flows to the pump that has received the control command so that the discharge capacity is reduced due to the pressure between the pumps. It can be difficult. As a result, only the amount of water below the desired flow rate flows into the refrigerator in which water flows from this pump. As a result, when setting the flow rate of water for each refrigerator, the water distributed to each refrigerator Since it is not possible to make a large difference in flow rate, it is impossible to distribute a desired load to each refrigerator, and the energy efficiency of the entire system may be deteriorated.

  In the present embodiment, water flows to the first heat source machine (first refrigerator 51) and the second heat source machine (second refrigerator 52 / third refrigerator 53) by a common pump 40, and the first The flow rate of water to the first heat source device and the second heat source device is adjusted by the 1 flow rate adjustment valve (first flow rate adjustment valve 61) and the second flow rate adjustment valve (second flow rate adjustment valve 62 / third flow rate adjustment valve 63). Is done. For this reason, it is the structure which water flows from the pump which can discharge capacity with respect to each of a 1st heat source machine and a 2nd heat source machine, Comprising: The flow volume of the water to a 1st heat source machine and a 2nd heat source machine is adjusted by each pump Rather than being done, when flowing water with respect to the 1st heat source machine and the 2nd heat source machine, a big difference can be given to the flow rate. Therefore, the flow rate of water distributed to the first heat source machine and the second heat source machine can be set appropriately.

  As a result, the deterioration of the energy efficiency of the entire system can be suppressed.

(4-2)
FIG. 4 is a schematic configuration diagram of a primary-side facility provided in a load distribution system as a conventional technique. FIG. 5 is a diagram for explaining the energy loss of each of the load distribution system according to the present embodiment and the load distribution system as the prior art. In addition, in FIG. 5, the energy loss range in each of the load distribution system which concerns on this embodiment, and the load distribution system as a prior art is typically shown by hatching.

  The load distribution system as a prior art is such that, in the heat medium circulation circuit 70 provided in the load distribution system according to the present embodiment, a valve that cannot change the flow rate when allowed is adopted as the first flow rate adjustment valve 61 ′. The configuration is the same as that of the present embodiment. Then, the refrigerators to be operated are determined in the order of the first refrigerator 51 ′, the second refrigerator 52 ′, and the third refrigerator 53 ′ so that the required load amount from the secondary equipment is processed. To do.

  Here, when the variable capacity type heat source unit is operated, the power consumption increases or decreases depending on the capacity. However, when the constant capacity type heat source unit is operated, the power consumption is the same regardless of the capacity. . For this reason, wasteful power consumption can be suppressed by adjusting the amount of the heat medium flowing through the constant-capacity type heat source unit so that the capability of the constant-capacity type heat source unit can be maximized.

  In the load distribution system as the prior art, the amount of water flowing to the first refrigerator 51 ′ cannot be adjusted. Therefore, when the operation of the second refrigerator 52 ′ is started in addition to the first refrigerator 51 ′, the first An equal amount of water flows through each of the refrigerator 51 ′ and the second refrigerator 52 ′. Then, a flow rate higher than the flow rate necessary for the first refrigerator 51 ′ to operate at the minimum capacity flows to the first refrigerator 51 ′, and as shown in FIG. The capacity of a certain second refrigerator 52 is lost up to 50%. Further, when the operation of the third refrigerator 53 ′ is started in addition to the first refrigerator 51 ′ and the second refrigerator 52 ′, the first to third refrigerators 51 ′ to 53 ′ each have an equal amount. Water flows. Then, as shown in FIG. 5, the capacity of the constant capacity type heat source machine (the second refrigerator 52 'and the third refrigerator 53') is lost up to about 67%.

  In the present embodiment, since the amount of water flowing to the first refrigerator 51 can be adjusted by providing the first flow rate adjustment valve 61, the amount of water necessary to operate the first refrigerator 51 with the minimum capacity. Water can flow to the first refrigerator 51 and the remaining water can flow to the second refrigerator 52 and the third refrigerator 53. Then, when starting the operation of the second refrigerator 52 in addition to the first refrigerator 51 or when starting the operation of the third refrigerator 53 in addition to the first refrigerator 51 and the second refrigerator 52, It is possible to operate the first refrigerator 51 with the minimum capacity and maximize the capabilities of the second refrigerator 52 and the third refrigerator 53. For this reason, as shown in FIG. 5, the loss of capacity of the constant capacity type heat source machine (second refrigerator 52 or third refrigerator 53) is 15% at the maximum. Therefore, the energy loss (loss) of the entire system can be suppressed as compared with the load distribution system as the prior art.

(4-3)
The pump 40 of the present embodiment is a constant speed pump in which the discharge amount of water per unit time is constant. For this reason, compared with the case where the capacity | capacitance variable pump driven by an inverter is employ | adopted, the cost can be suppressed.

(4-4)
In the present embodiment, a valve capable of changing the flow rate at the time of allowance is adopted for the first refrigerator 51 which is a variable capacity type heat source machine, and the second refrigerator 52 which is a constant capacity type heat source machine and For the third refrigerator 53, a valve that cannot change the flow rate when it is allowed is employed. That is, in the present embodiment, the second flow rate adjustment valve 62 and the third flow rate adjustment valve 63 are open / close valves that allow or shield the flow of water to the second refrigerator 52 and the third refrigerator 53, respectively. For this reason, compared with the case where the valve which can change a flow rate at the time of permission is adopted as the 2nd flow rate adjustment valve 62 and the 3rd flow rate adjustment valve 63, cost can be held down.

(4-5)
In the present embodiment, since the first refrigerator 51 is fixed to the minimum capacity when the operation of the second refrigerator 52 is started, it is possible to prevent the compressor from being stopped due to the thermo-off in the first refrigerator 51. . Thereby, while being able to respond | correspond quickly with respect to the required load amount from the secondary side equipment 20, the shortening of the apparatus lifetime by the increase in the frequency | count of a start / stop of a compressor can be prevented.

(4-6)
In this embodiment, the common pump 40 is employ | adopted with respect to the 1st-3rd refrigerator 51-53. In the present embodiment, for example, first to third flow rate adjusting valves are provided as compared with a system in which a pump capable of discharging capacity is provided on the upstream side of the refrigerator and the flow rate of water to the refrigerator is adjusted by each pump. Since the amount of water flowing to each of the first to third refrigerators 51 to 53 can be adjusted by 61 to 63, it is possible to suppress an increase in cost at the time of renewal (replacement or addition of a refrigerator) by adding a pump. it can.

(5) Modification (5-1) Modification A
FIG. 6 is a schematic configuration diagram of primary-side equipment included in the load distribution system according to Modification A. FIG. 7 is a diagram for explaining the energy loss of each of the load distribution system according to Modification A and the load distribution system as the prior art. In addition, in FIG. 7, the energy loss range in the load distribution system as a prior art is typically shown by hatching.

  In the above embodiment, only one variable capacity type heat source machine (first refrigerator 51) is provided among the plurality of heat source machines. Instead of this, two or more variable capacity type heat source units may be provided.

  For example, in the load distribution system according to Modification A, as shown in FIG. 6, the first refrigerator 251 and the second refrigerator 252 are variable capacity heat source machines, and the third refrigerator 253 has a constant capacity. It is a heat source machine of the type. In addition, the first flow rate adjustment valve 261 and the second flow rate adjustment valve 262 are valves that can change the flow rate when allowed, and the third flow rate adjustment valve 263 is a valve that cannot change the flow rate when allowed. And the 1st freezer 251, the 2nd freezer 252, and the 3rd freezer 253 are determined in order of the refrigerating machine to operate so that the demand load amount from the secondary side equipment may be processed. It is assumed that the minimum capacities of the first refrigerator 251 and the second refrigerator 252 that are variable capacity heat source machines are 15% as in the above embodiment. That is, in this modification, the total capacity of the first refrigerator 251 and the second refrigerator 252 is equal to or less than the rated capacity of the third refrigerator 253.

  On the other hand, the load distribution system as the prior art shown in FIG. 7 cannot change the flow rate when allowed as the first flow rate adjustment valve and the second flow rate adjustment valve in the heat medium circulation circuit provided in the load distribution system according to this modification. The configuration is the same as that of the present modification except that a valve is employed. And it shall determine in order of a 1st freezer, a 2nd freezer, and a 3rd freezer as a freezer to be operated so that a demand load amount from a secondary side equipment may be processed.

  The load distribution system as the prior art includes the first refrigerator and the second refrigerator as variable capacity heat source machines with a minimum capacity of 15%, but adjusts the amount of water flowing to the first refrigerator and the second refrigerator. Therefore, when the operation of the third refrigerator is started in addition to the first refrigerator and the second refrigerator, an equal amount of water flows through each of the first to third refrigerators. If it does so, a 1st freezer and a 2nd freezer cannot be operated by the minimum capacity, and as shown in Drawing 7, the capacity of the 3rd freezer will be lost about 33% at the maximum.

  On the other hand, in the present modification, the amount of water flowing to the first refrigerator 251 and the second refrigerator 252 can be adjusted by providing the first flow rate adjustment valve 261 and the second flow rate adjustment valve 262. Therefore, an amount of water necessary for operating the first refrigerator 251 and the second refrigerator 252 with the minimum capacity is allowed to flow to the first refrigerator 251 and the second refrigerator 252, and the remaining water is supplied to the third refrigerator. To the machine 253. Then, when starting the operation of the third refrigerator 253 in addition to the first refrigerator 251 and the second refrigerator 252, the first refrigerator 251 and the second refrigerator 252 are operated with the minimum capacity, and the third Since the capacity of the refrigerator 253 can be maximized, the energy loss of the third refrigerator 253 can be eliminated as shown in FIG.

  In this way, in the multiple heat source units with which the load distribution system is equipped, the total capacity of the minimum capacity of the variable capacity type heat source unit is equal to or less than the rated capacity of the constant capacity type heat source unit. When starting the operation of the constant capacity type heat source apparatus in addition to the heat source apparatus, the energy loss of the entire system can be suppressed by adjusting the flow rate of the heat medium to the variable capacity type heat source apparatus.

  Moreover, in the said embodiment, although the example provided with three refrigerators as a heat source apparatus which heats or cools a heat medium is shown, the number of heat source apparatuses is not limited to this, One or several units | sets are provided. It is only necessary that the variable capacity type heat source apparatus and one or a plurality of constant capacity type heat source apparatuses are provided in parallel. Further, the number of air conditioners that are heat utilization devices is not limited to the above embodiment.

(5-2) Modification B
In the said embodiment, although the 1st-3rd flow regulating valve 61-63 is provided in the upstream (inlet side) of each of the 1st-3rd refrigerator 51-53, it is downstream (outlet side). It may be provided.

  The present invention can suppress deterioration of energy efficiency of the entire system in a system including a plurality of heat source units, and includes a heat source unit having a variable speed compressor as a plurality of heat source units and a heat source having a constant speed compressor. It is effective to apply to a system equipped with a heat sink or an absorption heat source machine.

20 Secondary equipment (use equipment)
40 Pump 51 First refrigerator (first heat source machine)
52 Second refrigerator (second heat source machine)
53 Third refrigerator (second heat source)
61 1st flow regulating valve 62 2nd flow regulating valve 70 Heat medium circulation circuit 182 Refrigeration unit number determination part (control part)

JP 2007-292374 A

Claims (5)

A first heat source machine (51) for heating or cooling the heat medium;
A second heat source unit (52, 53) that heats or cools the heat medium and is arranged in parallel with the first heat source unit;
A use side facility (20) to which a heat medium is supplied from the first heat source machine and the second heat source machine;
A heat medium circulation circuit (70) to which the first heat source unit, the second heat source unit, and the use side facility are connected;
With
The first heat source machine is a heat source machine having a variable speed compressor,
The second heat source machine is a heat source machine having a constant speed compressor or an absorption heat source machine,
The heat medium circulation circuit is common to the first heat source device and the second heat source device, and a pump (40) for circulating the heat medium to the heat medium circulation circuit, and from the pump to the first heat source A first flow rate adjusting valve (61) for adjusting the flow rate of the heat medium flowing to the machine, and a second flow rate adjusting valve (62) for adjusting the flow rate of the heat medium flowing from the pump to the second heat source unit. 63), and provided
The pump is one unit for the first heat source unit and the second heat source unit.
Load distribution system. A control unit (182) for controlling the number of drive units of the first heat source unit and the second heat source unit according to a load required from the use side facility,
When the load required from the use-side facility gradually increases and a load greater than the load that can be handled by the first heat source device is requested, the control unit transfers the heat medium to the second heat source device. Adjusting the opening degree of the second flow rate adjustment valve so that the flow rate of the second flow rate adjustment valve and adjusting the opening degree of the first flow rate adjustment valve so that the first heat source device is driven with a minimum capacity,
The load distribution system according to claim 1. There are two or more first heat source machines,
The total capacity of the minimum capacity of the first heat source machine is less than or equal to the rated capacity of the second heat source machine.
The load distribution system according to claim 2. The pump is a metering pump in which the discharge capacity of the heat medium per unit time is constant.
The load distribution system according to any one of claims 1 to 3. The second flow rate adjustment valve is an on-off valve that allows or blocks the flow of the heat medium to the second heat source unit.
The load distribution system according to any one of claims 1 to 4.

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