JP6095360B2 - Thermal load treatment system - Google Patents

Description

  The present invention relates to a heat load processing system.

  As a system for heating or cooling air in an air-conditioning target space, a system disclosed in Patent Document 1 (Japanese Patent Laid-Open No. 2003-106731) is known. In the system according to Patent Document 1, a plurality of primary pumps, refrigerators or heaters as a plurality of heat source devices, a secondary pump, a heat exchanger, and the like are sequentially connected by piping, thereby forming a heat medium circuit. ing. Water as a heat medium circulates in the heat medium circuit, and the water is heated or cooled by heat exchange between the water and the air in the air-conditioning target space in the heat exchanger.

  As a control technique related to the above-mentioned Patent Document 1, heat source optimum control disclosed in Patent Document 2 (Japanese Patent Laid-Open No. 2009-14300) is known. In this heat source optimal control, a simulation related to air conditioning heat source equipment is executed based on the control set value, and so-called energy saving control is performed in which the control set value is guided in the direction of promoting energy saving based on the result.

  By the way, when performing the energy-saving control which concerns on patent document 2 with respect to the system which concerns on patent document 1, the flow rate of water (namely, primary side flow rate) which flows through each heat-source machine other than preset temperature of water is included in a control setting value. The control setting value is set every few minutes, for example. In a system in which the optimum value of the load factor of each heat source unit is different, the load factor of each heat source unit is set according to the control set value, and the flow rate of water is controlled so as to be the set load factor. On the other hand, since the load on the secondary side including the heat exchanger increases and decreases from moment to moment, the flow rate of water flowing through the heat exchanger (that is, the secondary side flow rate) changes accordingly. End up. Then, the control set value of the load factor of each heat source machine is not an appropriate value for the secondary flow rate changed after the set value is set, and control is performed to lead to the energy saving promotion direction. It becomes difficult to say.

  Therefore, an object of the present invention is to appropriately perform energy saving control.

The thermal load processing system according to the first aspect of the present invention includes a plurality of heat source units, a first pipe, a plurality of pumps, and a control unit. The plurality of heat source units heat or cool the heat medium, and optimum values of the load factors thereof are different from each other. The first pipe connects each of the plurality of heat source units and the utilization unit in an annular shape. The utilization unit utilizes a heat medium. The plurality of pumps are provided on the first pipe so as to correspond to each of the plurality of heat source machines. The plurality of pumps are inverter pumps that circulate a heat medium flowing in the first pipe between the heat source unit and the utilization unit. The control unit performs energy saving control. In the energy saving control, the control unit performs load factor adjustment control that adjusts the load factor of each heat source unit every predetermined time so that the total energy consumption is reduced. The total energy consumption is the total amount of energy consumed by at least the heat source unit and the pump. Further, in the energy saving control, when the flow rate of the heat medium flowing through the utilization unit changes during a predetermined time , the control unit is configured so that the increase / decrease ratio of the flow rate of the heat medium circulated by each predetermined pump is substantially equal to each other. Load ratio maintenance control is performed to change the inverter frequency of each pump. The predetermined pump is at least two of the plurality of pumps.

  According to this thermal load processing system, when the flow rate of the heat medium flowing through the utilization unit changes during a predetermined time, the predetermined pump which is at least two pumps so that the increase / decrease ratio of the flow rate of the heat medium becomes substantially equal. The inverter frequency changes. Then, each inverter frequency of the predetermined pump changes by the same rate as the increase / decrease rate of the flow rate of the heat medium flowing through the utilization unit, and the flow rate of the heat medium flowing through the heat source unit corresponding to the predetermined pump changes by the same rate. To come. As a result, the load factor of each heat source device related to the flow rate of the heat medium flowing through the heat source device can be changed to a value that is appropriate for the changed flow rate of the heat medium on the use unit side. Therefore, even if the flow rate of the heat medium flowing through the utilization unit changes during a predetermined time, the thermal load processing system can appropriately perform energy saving control using an appropriate load factor of the heat source unit. .

  The thermal load processing system according to the second aspect of the present invention is the thermal load processing system according to the first aspect, and the predetermined pump is a pump corresponding to the operating heat source unit among the pumps.

  Thereby, when the flow volume of the heat medium which flows through a utilization unit changes during predetermined time, the inverter frequency of each pump corresponding to the heat-source machine which is drive | operating will change.

  The thermal load processing system according to the third aspect of the present invention is the thermal load processing system according to the second aspect, and the control unit determines the number of heat source devices to be operated based on the load of the utilization unit. Then, the control unit increases the number of heat source devices to be operated when the flow rate of the heat medium flowing through the utilization unit is larger than the total value of the rated flow rates of the predetermined pumps.

  Thereby, only the required number of heat source units can be operated while suppressing the total energy consumption as much as possible.

  The thermal load processing system according to the fourth aspect of the present invention is the thermal load processing system according to the second aspect or the third aspect, and further includes a second pipe. The second pipe connects the inlet side and the outlet side of all of the plurality of heat source units. The control unit prevents at least each of the heat sources so that the heat medium does not flow in the second pipe so that the flow rate of the heat medium flowing through the utilization unit is equal to the total value of the flow rates of the heat medium flowing through the plurality of heat source units. Control to adjust the load factor of the machine.

  Thereby, the total value of the flow rate of the heat medium flowing through each heat source machine is minimized, and the energy consumption of the pump is minimized. Furthermore, since the heat medium does not flow through the second pipe, when the heat load processing system performs the cooling operation, the inlet temperature of each heat source unit becomes the highest, and the COP of each heat source unit improves.

  A thermal load processing system according to a fifth aspect of the present invention is the thermal load processing system according to the fourth aspect, wherein the control unit adds the rated flow rate of all the predetermined pumps to the flow rate of the heat medium flowing through the utilization unit. By multiplying the ratio of the rated flow rate of each predetermined pump to the ratio, the increase / decrease ratio of each predetermined pump is made substantially equal to each other.

  Thereby, the thermal load processing system can ensure that the increase / decrease ratio of each predetermined pump is substantially equal.

  A thermal load processing system according to a sixth aspect of the present invention is the thermal load processing system according to any one of the second to fifth aspects, and the control unit circulates in two or more predetermined pumps. When there is a first predetermined pump in which the flow rate of the heating medium exceeds the rated flow rate, the difference between the rated flow rate and the flow rate of the heating medium to be circulated is compensated by the second predetermined pump. Adjust the increase / decrease ratio. The second predetermined pump is a remaining pump excluding the first predetermined pump from the predetermined pump.

  Accordingly, even if there is the first predetermined pump in which the flow rate of the heat medium to be circulated exceeds the rated flow rate, all of the flow rate of the heat medium to be circulated is reliably circulated between the heat source unit and the utilization unit. Become.

  According to the thermal load processing system according to the first aspect of the present invention, even if the flow rate of the heat medium flowing through the utilization unit changes during a predetermined time, the energy saving control is appropriately performed using the appropriate load factor of the heat source unit. Can be performed.

  According to the thermal load processing system according to the second aspect of the present invention, when the flow rate of the heat medium flowing through the utilization unit changes during a predetermined time, the inverter frequency of each pump corresponding to the operating heat source machine changes. It will be.

  According to the thermal load processing system according to the third aspect of the present invention, the necessary number of heat source units can be operated while suppressing the total energy consumption as much as possible.

  According to the thermal load processing system according to the fourth aspect of the present invention, the total value of the flow rate of the heat medium flowing through each heat source unit is minimized, and the energy consumption of the pump is minimized. Furthermore, since the heat medium does not flow through the second pipe, when the heat load processing system performs the cooling operation, the inlet temperature of each heat source unit becomes the highest, and the COP of each heat source unit improves.

  The thermal load processing system according to the fifth aspect of the present invention can ensure that the increase / decrease ratio of each predetermined pump is substantially equal.

  According to the thermal load processing system according to the sixth aspect of the present invention, even if there is a first predetermined pump in which the flow rate of the heat medium to be circulated exceeds the rated flow rate, all the flow rates of the heat medium to be circulated are ensured. It will circulate between a heat source machine and a utilization unit.

1 is a schematic configuration diagram of a thermal load processing system according to an embodiment of the present invention. The schematic block diagram of a chiller unit. The wet air diagram which shows air cooling and dehumidification at the time of air_conditioning | cooling dehumidification driving | operation. The humid air line figure which shows air cooling and humidification at the time of air_conditioning | cooling humidification driving | operation. The humid air line figure which shows the heating and dehumidification of air at the time of a dehumidification heating driving | operation. The humid air line figure which shows the heating and humidification of the air at the time of humidification heating operation. The figure showing the state where each utilization unit is connected to the corresponding air-conditioning object space. The block diagram which shows typically the various apparatuses connected to the system controller, and the inside of this controller. The flowchart showing the operation | movement of the heat source number control in the optimal load factor maintenance control which concerns on this embodiment. The graph showing the characteristic of each chiller unit at the time of capability compensation control in the optimal load factor maintenance control which concerns on this embodiment.

  Hereinafter, a thermal load treatment system according to the present invention will be described in detail 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 Thermal Load Processing System FIG. 1 is a schematic configuration diagram of a thermal load processing system 10 according to an embodiment of the present invention. The thermal load processing system 10 performs the energy-saving optimal control operation that suppresses the total energy consumption (that is, the total power consumption) of the entire system 10 as much as possible, and converts the air adjusted to the optimum temperature into the air-conditioning target spaces RMa, RMb. , RMc (see FIG. 7). Mainly, the heat load processing system 10 is installed in a relatively large building such as a building, a factory, a hospital, or a hotel.

  As shown in FIGS. 1 and 2, such a thermal load processing system 10 mainly includes a chiller unit group 20, a utilization unit group 30, communication pipes L1 to L4 (corresponding to a first pipe), a communication pipe L5 ( Secondary pumps), primary pumps 44a to 44c (corresponding to pumps), secondary pumps 46 and 47, and a system controller 80 (corresponding to a controller). Further, the thermal load processing system 10 includes a flow meter 48, a power meter 49, and a plurality of temperature detection sensors T1, T2, T3a, T3b, T3c, T4a, T4b, and T4c.

  A refrigerant circuit 21 shown in FIG. 2 is configured inside a plurality of chiller units 20a, 20b, and 20c (corresponding to a heat source device) constituting the chiller unit group 20. Further, as shown in FIG. 1, the chiller unit group 20 is also connected to a cooling tower 70, and a heat dissipation circuit 60 is configured by these. As shown in FIG. 1, the heat medium circuit 40 is configured by the primary side pumps 44 a to 44 c, the chiller unit group 20, the secondary side pumps 46 and 47, the utilization unit group 30, and the like.

(2) Detailed configuration of thermal load processing system (2-1) Chiller unit group and refrigerant circuit The chiller unit group 20 according to the present embodiment includes a plurality of chiller units 20a to 20c. Each of the chiller units 20a to 20c is a water-cooled heat source machine and is connected in parallel to each other and includes the refrigerant circuit 21 shown in FIG.

  The refrigerant circuit 21 is configured by sequentially connecting a compressor 22, a radiator 23, a chiller side expansion valve 24, an evaporator 25, and the like. The refrigerant circuit 21 is filled with a refrigerant.

  The compressor 22 can adjust the operating capacity. Electric power is supplied to the motor of the compressor 22 via an inverter. When the output frequency of the inverter is changed, the rotational speed of the motor, that is, the rotational speed is changed, and the operating capacity of the compressor 22 changes.

  The radiator 23 has a first heat transfer tube connected to the refrigerant circuit 21 and a second heat transfer tube connected to the heat dissipation circuit 60. The radiator 23 exchanges heat between the refrigerant flowing in the first heat transfer tube on the refrigerant circuit 21 side and the heat medium flowing in the second heat transfer tube on the heat dissipation circuit 60 side.

  The chiller side expansion valve 24 is for depressurizing the refrigerant in the refrigerant circuit 21 and flowing out the depressurized refrigerant, and is constituted by an electric expansion valve.

  The evaporator 25 has a third heat transfer tube connected to the refrigerant circuit 21 and a fourth heat transfer tube connected to the heat medium circuit 40. The evaporator 25 exchanges heat between the refrigerant flowing in the third heat transfer tube on the refrigerant circuit 21 side and the heat medium flowing in the fourth heat transfer tube on the heat medium circuit 40 side.

  Each chiller unit 20a-20c including such a refrigerant circuit 21 cools or heats water as a heat medium. In particular, in the present embodiment, load factors that can be optimally operated by the chiller units 20a to 20c (that is, optimum values of load factors, hereinafter referred to as optimum load factors) are different from each other. As an example, the optimum load factor of each of the chiller units 20a to 20c is “70%”, “40%”, and “30%” in order.

(2-2) Heat Dissipation Circuit The heat dissipation circuit 60 is filled with water as a heat medium. The heat dissipation circuit 60 is mainly configured by sequentially connecting the radiator 23, the water pump 61, and the cooling tower 70 in each of the chiller units 20 a to 20 c. The water pump 61 can adjust the discharge flow rate and circulates the water in the heat dissipation circuit 60. In the cooling tower 70, water circulating in the heat dissipation circuit 60 is cooled.

  In FIG. 1, the arrow attached to the water pump 61 represents the direction of water flow in the heat dissipation circuit 60.

(2-3) Heat medium circuit, flow meter and temperature detection sensor The heat medium circuit 40 constitutes a closed circuit filled with water as the heat medium. The heat medium circuit 40 mainly includes primary side pumps 44a, 44b, and 44c, an evaporator 25 in each chiller unit 20a to 20c, a bypass valve 45, secondary side pumps 46 and 47, and a utilization unit group 30. The usage-side heat exchangers 33a, 33b, 33c and the usage-side valves 32a, 32b, 32c in the respective usage units 30a, 30b, 30c to be configured are sequentially connected by connecting pipes L1 to L4. . Furthermore, the heat medium circuit 40 is also configured by connecting the inlet side and the outlet side of each of the chiller units 20a to 20c through the communication pipe L5.

  Specifically, one end of the connection pipe L1 is connected to one end of the evaporator 25 that is the outlet side of each chiller unit 20a to 20c, and the other end is connected to the second feed header 43 via the first feed header 42. Has been. One end of the communication pipe L <b> 2 is connected to the outlet of the second feed header 43. The other end side of the connection pipe L2 is branched in the middle, and the branching tip is connected to the use side heat exchangers 33a to 33c which are the inlet sides of the use units 30a to 30c. One end of the communication pipe L3 is connected to the outlet side of each use side valve 32a to 32c which is the outlet side of each use unit 30a to 30c. The other end side of the connecting pipe L <b> 3 joins on the way, and the joining tip part is connected to the return header 41. Three communication pipes L4 are provided according to the number of chiller units 20a to 20c. One end of each connecting pipe L4 is connected to the return header 41, and the other end is connected to the other end of the evaporator 25 on the inlet side of each of the chiller units 20a to 20c. That is, it can be said that the communication pipes L1 to L4 connect the chiller units 20a to 20c and the utilization units 30a to 30c in a ring shape, and water as a heat medium flows through the communication pipes L1 to L4.

  The communication pipe L5 connects the inlet side and outlet side of all the chiller units 20a to 20c (specifically, the inlet side and outlet side of the evaporator 25) via the first feed header 42 and the return header 41. Connected. Specifically, the connecting pipe L1 connected to the inlet side of each chiller unit 20a-20c is connected to the first feed header 42, and the connecting pipe L4 connected to the outlet side of each chiller unit 20a-20c is , Connected to the return header 41. The communication pipe L5 connects the first feed header 42 and the return header 41 to connect the inlet side and the outlet side of the chiller units 20a to 20c without using the use units 30a to 30c. In the communication pipe L5, water that does not flow in the use units 30a to 30c out of the water that is the heat medium flowing out from the chiller units 20a to 20c flows to the return header 41 side. That is, it can be said that the communication pipe L5 is a pipe for returning water that is not used by the use units 30a to 30c to the chiller units 20a to 20c again.

  Three primary pumps 44a to 44c are provided corresponding to each of the chiller units 20a to 20c on the communication pipe L4. The primary pumps 44 a to 44 c are variable capacity pumps capable of adjusting the capacity and adjusting the discharge capacity, and are inverter-driven by the system controller 80. That is, it can be said that the primary pumps 44a to 44c according to the present embodiment are inverter pumps. Such primary side pumps 44a to 44c are connected to the usage units 30a to 30c (more specifically, the usage side valves 32a as shown by the arrows attached to the primary side pumps 44a to 44c in FIG. The water in the heat medium circuit 40 is circulated by sending the water as the heat medium flowing out from ~ 32c to each of the chiller units 20a to 20c. That is, the primary side pumps 44a to 44c circulate the heat medium (that is, water) flowing through the communication pipes L1 to L4 between the chiller units 20a to 20c and the utilization units 30a to 30c.

  In the evaporator 25, the water circulating in the heat medium circuit 40 is cooled, for example.

  The bypass valve 45 adjusts the flow rate of water flowing to the chiller unit 20a. That is, the flow rate of the water flowing through the chiller unit 20 a is determined by the opening degree of the bypass valve 45.

  Two secondary pumps 46 and 47 are provided between the first feed header 42 and the second feed header 43 on the connection pipe L1 so as to correspond to the chiller units 20b and 20c. Similar to the primary side pumps 44 a to 44 c, the secondary side pumps 46 and 47 are variable capacity type pumps capable of adjusting the capacity and adjusting the discharge capacity, and are inverter-driven by the system controller 80. That is, it can be said that the secondary pumps 46 and 47 according to the present embodiment are also inverter type pumps. Such secondary pumps 46 and 47, as shown by the arrows attached to the secondary pumps 46 and 47 in FIG. 1, water as a heat medium flowing out from the chiller units 20b and 20c, The water in the heat medium circuit 40 is circulated by sending to each utilization unit 30a-30c.

  The usage side valves 32a to 32c and the usage side heat exchangers 33a to 33c in the usage units 30a, 30b, and 30c will be described in “(2-4) Usage unit group”.

  Further, the heat medium circuit 40 is provided with a flow meter 48 and a plurality of sensors T1, T2, T3a to T3c, and T4a to T4c. The flow meter 48 is a part of the communication pipe L3 on which water flowing out from each of the usage units 30a to 30c flows and is attached to the front side of the return header 41. The flow meter 48 measures the total amount q2all of the flow rate of water that has flowed through the use units 30a to 30c.

  The temperature detection sensor T1 is attached to the vicinity of the second feed header 43 on the connecting pipe L2 before the pipe L2 is branched. The temperature detection sensor T1 detects the temperature of water that is a heat medium flowing in the communication pipe L2. The temperature detection sensor T2 is attached to the return header 41 in the portion of the connecting pipe L3 after the pipe L3 has joined. The temperature detection sensor T2 detects the temperature of water that is a heat medium flowing in the communication pipe L3. Three temperature detection sensors T3a to T3c are provided near the inlet of the chiller units 20a to 20c on the connection pipe L4 so as to correspond to the chiller units 20a to 20c. The temperature detection sensor T3 detects the temperature of water that is a heat medium flowing through each communication pipe L4, that is, the inlet temperatures Twin1 to Twin3 of the chiller units 20a to 20c. Three temperature detection sensors T4a to T4c are provided in the vicinity of the outlets of the chiller units 20a to 20c on the connection pipe L1 so as to correspond to the chiller units 20a to 20c. The temperature detection sensor T4 detects the temperature of water that is a heat medium flowing in each communication pipe L1, that is, the outlet temperatures Twout1 to Twout3 of the chiller units 20a to 20c.

  The detection results by the flow system 48 and the temperature detection sensors T1 to T2, T3a to T3a, and T4a to T4c are taken into the system controller 80 and used for various controls.

(2-4) Utilization Unit Group As shown in FIG. 1, the utilization unit group 30 includes a plurality of utilization units 30a, 30b, and 30c connected in parallel to each other. As illustrated in FIG. 7, the usage units 30a to 30c are installed in different air-conditioning target spaces RMa, RMb, and RMc.

  Each utilization unit 30a-30c has a substantially rectangular parallelepiped casing 31a-31c. Air passages through which air flows are formed in the respective casings 31a to 31c. One end of suction ducts 31ab, 31bb, 31cb is connected to the inflow end of the air passage, and one end of air supply ducts 31aa, 31ba, 31ca is connected to the outflow end of the air passage. The other ends of the suction ducts 31ab to 31cb and the air supply ducts 31aa to 31ca are connected to the air conditioning target spaces RMa to RMc, respectively.

  Inside each casing 31a-31c, in addition to the use side valves 32a-32c and the use side heat exchangers 33a-33c constituting the heat medium circuit 40, electric heaters 34a, 34b, 34c, watering type humidifiers 35a, 35b , 35c and blower fans 36a, 36b, 36c are provided. In particular, in the air passages in the respective casings 31a to 31c, the use side heat exchangers 33a to 33b, the electric heaters 34a, 34b, and 34c, and the watering humidifiers 35a, 35b, and 35c are sequentially arranged from the upstream side toward the downstream side. And ventilation fans 36a, 36b, and 36c are provided.

  The use side valves 32a to 32c adjust the amount of water flowing to the use side heat exchangers 33a to 33c, respectively. That is, the flow rate of the water flowing through the use units 30a to 30c is determined by the opening degree of each of the use side valves 32a to 32c.

  The use side heat exchangers 33a to 33c heat or exchange the air RAa to RAc by performing heat exchange between the air RAa, RAb, and RAc in the air-conditioning target spaces RMa to RMC and the water in the heat medium circuit 40. Allow to cool. Specifically, the use side heat exchangers 33a to 33c are fin-and-tube heat exchangers having a plurality of heat transfer fins and a heat transfer tube penetrating the heat transfer fins. Water that circulates through the heat medium circuit 40 flows through the heat transfer tubes of the use side heat exchangers 33a to 33c, and the heat of the water is supplied to the air through the heat transfer tubes and the heat transfer fins, thereby heating the air. Or it is supposed to be cooled.

  The electric heaters 34a to 34c are devices for raising the temperature of the air. The electric heaters 34a to 34c can change the output stepwise, and can adjust the amount of heating of air.

  The watering type humidifiers 35a to 35c are connected to a tank (not shown) installed outside the casings 31a to 31c. The watering type humidifiers 35a to 35c humidify the air flowing in the casings 31a to 31c by spraying the water in the tank from the nozzles into the air. That is, the watering type humidifiers 35a to 35c are devices for increasing the humidity of the air and can adjust the amount of humidification to the air.

  The blower fans 36a to 36c are blowers that can change the rotational speed stepwise by inverter control and can adjust the blown amount of heated or cooled air. The blower fans 36a to 36c generate a flow of air blown into the air-conditioning target spaces RMa to RMc via the use side heat exchangers 33a to 33c, the electric heaters 34a to 34c, and the watering type humidifiers 35a to 35c. Hereinafter, the air blown into the air conditioning target spaces RMa to RMc is referred to as supply air SAa, SAb, SAc.

  Furthermore, as shown in FIG. 7, various sensors S1a to S4a, S1b to S4b, and S1c to S4c are provided in each usage unit 30a to 30c. Specifically, each use unit 30a-30c includes water inlet temperature sensors S1a, S1b, S1c, water outlet temperature sensors S2a, S2b, S2c, air inlet temperature sensors S3a, S3b, S3c, and air. Inlet humidity sensors S4a, S4b, and S4c are provided.

  The water inlet temperature sensors S1a to S1c are provided in the vicinity of the water inlets of the use side heat exchangers 33a to 33c in the use units 30a to 30c, and the water flowing into the use units 30a to 30c. Detect the temperature of The water outlet temperature sensors S2a to S2c are provided in the vicinity of the water outlets of the use side valves 32a to 32c in the use units 30a to 30c, and the water after heat exchange flowing out from the use units 30a to 30c. Detect temperature. The air inlet temperature sensors S3a to S3c are provided in the vicinity of the inlet of the air RAa to RAc, which is a connection portion between the casings 31a to 31c and the suction ducts 31ab to 31cb, and the casing 31a is interposed via the suction ducts 31ab to 31cb. The temperature of the air RAa to RAc flowing into the interior of 31c is detected. Similarly to the air inlet temperature sensors S3a to S3c, the air inlet humidity sensors S4a to S4c are provided in the vicinity of the inlets of the air RAa to RAc, which are connection portions between the casings 31a to 31c and the suction ducts 31ab to 31cb. The humidity of the air RAa to RAc flowing into the casings 31a to 31c through the suction ducts 31ab to 31cb is detected. The detection results of these sensors S1a to S4a, S1b to S4b, and S1c to S4c are taken into the system controller 80 and used for various controls.

(2-5) Wattmeter As shown in FIG. 1, the commercial power supply 90 and the cooling tower 70 are electrically connected by power supply wiring, and use units 30 a to 30 c that are components of the thermal load processing system 10. The power from the commercial power source 90 is supplied via the cooling tower 70. The wattmeter 49 is attached on the power supply wiring that connects the commercial power supply 90 and the cooling tower 70. The wattmeter 49 measures the total energy consumption (that is, power consumption) of the entire heat load processing system 10.

(2-6) System Controller The system controller 80 is for comprehensively controlling the thermal load processing system 10. The system controller 80 will be described in detail later.

(3) Basic operation of thermal load processing system Next, the operation of the thermal load processing system 10 will be described. The heat load processing system 10 includes a cooling and dehumidifying operation for cooling and dehumidifying air (FIG. 3), a cooling and humidifying operation for cooling and humidifying air (FIG. 4), and a heating and dehumidifying operation for dehumidifying and heating air. Any one of (FIG. 5) and heating humidification operation (FIG. 6) which performs heating and humidification of air can be performed. Thereby, the thermal load processing system 10 can perform the air conditioning operation so that the temperature and humidity in the air-conditioning target spaces RMa to RMc become, for example, 23 ° C. which is the set temperature and 50% which is the set humidity. .

(3-1) Cooling and Dehumidifying Operation In the cooling and dehumidifying operation shown in FIG. 3, the compressor 22, the various pumps 44a to 44c, 46, 47, 61, and the blower fans 36a to 36c are operated.

  In the cooling and dehumidifying operation, basically, the electric heaters 34a to 34c are stopped, and the watering of the watering humidifiers 35a to 35c is also stopped. In the cooling and dehumidifying operation, a refrigeration cycle is performed in the refrigerant circuit 21. Specifically, the refrigerant compressed by the compressor 22 dissipates heat into the water flowing through the heat dissipation circuit 60 and condenses in the radiator 23. The refrigerant cooled by the radiator 23 is depressurized by the chiller side expansion valve 24 and then evaporates by absorbing heat from the water flowing through the heat medium circuit 40 in the evaporator 25. The refrigerant evaporated in the evaporator 25 is sucked into the compressor 22 and compressed. The water flowing through the heat dissipation circuit 60 heated by the radiator 23 radiates heat to the outdoor air in the cooling tower 70. In the heat medium circuit 40, the water cooled by the evaporator 25 of the refrigerant circuit 21 cools the air flowing through the air passages in the casings 31a to 31c in the use side heat exchangers 33a to 33c. The water that has passed through the use side heat exchangers 33a to 33c returns to the evaporator 25 of the refrigerant circuit 21 and is cooled again. In the heat medium circuit 40, the cold heat obtained by the water from the refrigerant in the evaporator 25 is conveyed to the use side heat exchangers 33a to 33c and supplied to the air.

  In each usage unit 30a-30c, as already described, the indoor air RAa-RAc taken in from each of the air-conditioning target spaces RMa-RMc by the suction ducts 31ab-31cb flows through the air passages in the casings 31a-31c. This air is cooled and dehumidified by the water in the heat medium circuit 40 in each of the use side heat exchangers 33a to 33c. The air cooled and / or dehumidified in each use side heat exchanger 33a-33c is supplied to each air-conditioning target space RMa-RMc as supply air SAa-SAc via the air supply ducts 31aa-31ca.

(3-2) Cooling / humidifying operation The cooling / humidifying operation shown in FIG. 4 is an operation in which humidification is performed by watering the watering-type humidifiers 35a to 35c in addition to the dehumidifying / cooling operation. Until the air is cooled and dehumidified by the water of the heat medium circuit 40 in each of the use side heat exchangers 33a to 33c, it is the same as the above-described cooling and dehumidifying operation. Watering by the type humidifiers 35a to 35c is performed.

  By cooling and / or dehumidifying by the use side heat exchangers 33a to 33c, the temperature of the supply air SAa to SAc can reach a desired set temperature. However, this cooling / humidifying operation is performed when the humidity in the air-conditioning target spaces RMa to RMC falls below a desired set humidity due to the dehumidifying effect accompanying cooling.

(3-3) Heating / Dehumidifying Operation The heating / dehumidifying operation shown in FIG. 5 is an operation called a reheat dehumidifying operation. With the dehumidification and / or cooling by the use side heat exchangers 33a to 33c, the humidity of the supply air SAa to SAc can reach a desired set humidity. However, this heating and dehumidifying operation is performed when the temperature in the air conditioning target spaces RMa to RMc falls below a desired set temperature due to the cooling effect accompanying dehumidification.

  In the dehumidifying and heating operation, when the amount of cold supplied to the air for dehumidification is large in each of the use side heat exchangers 33a to 33c and the air is cooled more than necessary, the electric heaters 34a to 34c are activated. Reheat the air.

(3-4) Heating / humidifying operation In the heating / humidifying operation shown in FIG. 6, the electric heaters 34a to 34c, the watering humidifiers 35a to 35c, and the blower fans 36a to 36c are operated. On the other hand, the operation of the compressor 22 and the various pumps 44a to 44c, 46, 47, 61 is stopped.

  In the heating / humidifying operation, the air RAa-RAc taken in from the air-conditioning target spaces RMa-RMc is first heated by the electric heaters 34a-34c in each of the usage units 30a-30c, and then the watering humidifiers 35a-35c. Are supplied into the air-conditioned spaces RMa to RMc as supply air SAa to SAc.

(4) Detailed Description of System Controller FIG. 8 is a block diagram schematically showing the internal configuration of the system controller 80 according to this embodiment and various devices connected to the controller 80. As shown in FIG. 8, the system controller 80 is mainly composed of a memory 81 and a CPU 82, and includes chiller units 20a to 20c, usage units 30a to 30c, various pumps 44a to 44c, 46, 47, 61, and a flow rate. It is connected with the total 48, the wattmeter 49, and various sensors T1-T2, T3a-T3c, T4a-T4c, S1a-S4a, S1b-S4b, S1c-S4c. The system controller 80 is based on the measurement results of the flow meter 48 and the wattmeter 49 and the detection results of the various sensors T1 to T2, T3a to T3c, T4a to T4c, S1a to S4a, S1b to S4b, and S1c to S4c. The basic operation of the thermal load processing system 10 described above is performed by controlling the units 20a to 20c, the use units 30a to 30c, and the various pumps 44a to 44c.

  The memory 81 includes a ROM and a RAM, and various programs that are read and executed by the CPU 82 are stored in the ROM. The RAM functions as a work memory for the CPU 82 and stores various information that can be rewritten by the CPU 82.

  The main control performed by the system controller 80 is terminal differential pressure control. The terminal differential pressure control is a control for supplying water of an appropriate flow rate to the use units 30a to 30c (that is, the end use units 30a to 30c) located farthest from the chiller unit group 20 side. is there. This is because the thermal load processing system 10 includes a plurality of usage units 30a to 30c as shown in FIG.

  For example, it is assumed that the individual usage units 30a to 30c are installed at different levels in a building, while the chiller unit group 20 is installed at the lowest level. It is assumed that the use unit (for example, use unit 30a) installed in the uppermost layer is a unit installed farthest from the chiller unit group 20. In this case, in the use unit 30a located at the farthest position, even if the opening of the use side valve 32a is fully opened, the pressure difference between the inlet side and the outlet side of the unit 30a (that is, water supply pressure) is insufficient. If it does, the appropriate quantity of water will not be supplied to the utilization unit 30a. Then, the system controller 80 performs terminal differential pressure control as control which sends water reliably to each utilization unit 30a-30c by keeping the said water supply pressure appropriately.

  In addition to the terminal differential pressure control, the main control performed by the system controller 80 is energy-saving optimum control. The energy-saving optimum control is to adjust the optimum operating parameters related to various components of the thermal load processing system 10 every predetermined time so that the total energy consumption of the entire thermal load processing system 10 is reduced. Control for operating various components. Such energy-saving optimum control is performed in parallel with the terminal differential pressure control.

  Here, the total energy consumption includes at least the energy consumed by the chiller units 20a to 20c and the primary pumps 44a to 44c. The total energy consumption according to the present embodiment includes heat load processing such as the secondary pumps 46 and 47 and the usage units 30a to 30c in addition to the energy consumption in the chiller units 20a to 20c and the primary pumps 44a to 44c. It is assumed that the amount of energy consumed by the components of the system 10 that can be the target of power consumption is also included.

  Hereinafter, the energy-saving optimum control will be described in detail. In energy-saving optimal control, the operation parameter calculation process for minimizing the total energy consumption is the measurement result of the flow meter 48 (specifically, the total value of the flow rate of water flowing through the use units 30a to 30c). And a device model showing the detection results of various sensors T1 to T2, T3a to T3c, T4a to T4c, S1a to S4a, S1b to S4b, and S1c to S4c, and characteristics of various devices constituting the thermal load processing system 10. Is used every predetermined time. The operation parameters required in this calculation process include the load factor of each of the chiller units 20a to 20c, the temperature of the water circulating in the heat medium circuit 40, the water supply pressure of the secondary pumps 46 and 47, and the like.

  And the flow volume of water (henceforth the primary side flow volume q1) which flows into each chiller unit 20a-20c is controlled by controlling various apparatuses using the calculated | required operation parameter. 1, the outlet temperatures Twout1 to Twout3 of the chiller units 20a to 20c are equal to each other, and the inlet temperatures Twin1 to Twin3 of the chiller units 20a to 20c are also equal to each other. The capacities 20a to 20c are proportional to the primary flow rate q1. Therefore, the system controller 80 can set the actual load factor of each chiller unit 20a-20c to the optimum load factor by controlling the primary flow rate q1 of each chiller unit 20a-20c.

  In summary, in the energy saving optimal control, the primary flow rate q1 for the purpose of reducing the total energy consumption is controlled every predetermined time. Then, actual operation data (for example, the number of operating chiller units 20a to 20c, etc.) after the control of the primary flow rate q1 is further calculated in an operation parameter calculation process performed after a predetermined time has elapsed. And used as a so-called feedback element.

  However, the operating status of the usage units 30a to 30c on the secondary side with respect to the chiller units 20a to 20c changes even during the predetermined time. Therefore, the heat load of the usage units 30a to 30c on the secondary side changes from time to time by changing how much the usage units 30a to 30c are operating in what state. Then, the flow rate of water flowing through each of the usage units 30a to 30c (hereinafter referred to as the secondary side flow rate q2) changes with the change in the thermal load of the usage units 30a to 30c. Therefore, the system controller 80 changes the total amount q1all of the primary side flow rate q1 of the chiller units 20a to 20c by following the change of the secondary side flow rate q2 (specifically, the total amount q2all of the secondary side flow rate q2). It is necessary to control. However, when the system controller 80 performs such control, the optimum load factor of the chiller units 20a to 20c adjusted every predetermined time elapses is not necessarily the optimum value for the changed primary flow rate q1. It becomes difficult to say. That is, the optimum load factor included in the obtained operation parameter is different from the load factor that can be said to be optimum at present.

  Therefore, the system controller 80 according to the present embodiment is configured so that the actual chiller units 20a to 20c are optimally loaded even when the total amount q2all of the secondary flow rate q2 changes during a predetermined time in the energy saving optimal control. The optimal load factor maintenance control for maintaining the rate is performed. The optimal load factor maintenance control is the inverter frequency of each of the predetermined pumps that are at least two primary pumps among the three primary pumps 44a to 44c when the total amount q2all of the secondary flow q2 changes during a predetermined time. Is controlled so that the increase / decrease ratio of the flow rate of the water circulated by each predetermined pump becomes substantially equal to each other.

  Here, the predetermined pump specifically refers to the primary pumps 44a to 44c corresponding to the operating chiller units 20a to 20c among the primary pumps 44a to 44c. That is, the optimum load factor maintenance control is control performed in a state where at least two chiller units 20a to 20c and at least two corresponding primary pumps 44a to 44c are operating. .

  In the following, a specific control operation performed by the CPU 82 of the system controller 80 in the optimum load factor maintenance control will be described.

(4-1) Heat Source Number Control Operation FIG. 9 shows the flow of the control operation of the heat source number control performed in the optimum load factor maintenance control according to the present embodiment. As shown in FIG. 9, first, the CPU 82 calculates a secondary side thermal load that is a thermal load of the usage units 30a to 30c (S1). Specifically, the CPU 82 measures the total amount q2all of the secondary-side flow rate q2 that is the measurement result of the flow meter 48, and the inlet temperature Twin1 of the chiller units 20a to 20c that is the detection result of each of the temperature detection sensors T3a to T3c and T4a to T4c. ˜Twin3 and outlet temperatures Twout1 to Twout3 are applied to the following equation (1) to obtain the secondary heat load Lo2. The secondary side heat load Lo2 corresponds to the total value of the loads of all the usage units 30a to 30c.

上式（１）の“Ｎ”は、１〜３のいずれかの整数であって、どのチラーユニット２０ａ〜２０ｃにおける入口温度Ｔｗｉｎ１〜Ｔｗｉｎ３及び出口温度Ｔｗｏｕｔ１〜Ｔｗｏｕｔ３であるのかを表している。上式（１）の“Ａ”は、定数を表している。

“N” in the above formula (1) is an integer of 1 to 3, and indicates which chiller unit 20a to 20c has the inlet temperature Twin1 to Twin3 and the outlet temperature Twout1 to Twout3. In the above formula (1), “A” represents a constant.

  Next, based on the secondary side thermal load Lo2 calculated in step S1, the CPU 82 is under the condition that the total amount q2all of the secondary side flow rate q2 is smaller than the total value Tr of the rated flow rates Rf1, Rf2, Rf3 of the predetermined pump ( q2all <Tr), and determines the number of chiller units 20a to 20c to be operated (S2). Then, the CPU 82 operates the chiller units 20a to 20c corresponding to the determined number and the primary pumps 44a to 44c corresponding thereto, and determines the operated primary pumps 44a to 44c as predetermined pumps (S3).

  Note that the rated flow rates Rf1 to Rf3 of the predetermined pump are the water that can be circulated by the primary pumps 44a to 44c that are operating on the primary side of the heat medium circuit 40, that is, on the chiller units 20a to 20c side. Corresponds to the upper limit of flow rate.

  As described above, the operation parameter calculation process is performed at predetermined time intervals. When the total amount q2all of the secondary flow rate q2 changes during the predetermined time (Yes in S4), The CPU 82 compares the total amount q2all of the secondary flow rate q2 with the total value Tr of the rated flow rates Rf1 to Rf3 of the current predetermined pump (that is, the primary pumps 44a to 44c that are operating) (S5). When the current total amount q2all of the secondary flow rate q2 is larger than the total value Tr of the rated flow rates Rf1 to Rf3 of the predetermined pump (q2all> Tr, Yes of S5), the CPU 82 has the chiller units 20a to 20c to be operated. And the number of the primary side pumps 44a-44c corresponding to this is increased, and a predetermined pump is updated according to the operating primary side pumps 44a-44c (S6). This is to avoid that the total amount q2all of the water flowing through each of the usage units 30a to 30c is larger than the total amount q1all of the water flowing through each of the chiller units 20a to 20c (q2all> q1all).

  However, in step S4, when the total amount q2all of the secondary side flow rate q2 does not change during the predetermined time (Bo of S4), and in step S5, the total amount q2all of the secondary side flow rate q2 is the rated flow rate Rf1 to Rf1 of the predetermined pump. When it is smaller than the total value Tr of Rf3 (q2all <Tr, No in S5), the state of step S3 is waited until the next operation parameter adjustment time is reached. Even after step S6, the state of step S3 is on standby until the next operation parameter adjustment time comes.

  A specific example of the heat source number control described above will be described. Temporarily, the secondary side thermal load Lo2 obtained by the above equation (1) is “80 kW”, the capacities of the chiller units 20a to 20c are “50 kW”, “40 kW”, “30 kW” in order, and the rated flow rates of the primary side pumps 44a to 44c. Assume that Rf1 to Rf3 are “143 L / min”, “114 L / min”, and “86 L / min” in order. When the control of the number of heat sources is performed in the order of the chiller units 20a to 20c, the CPU 82 should operate the chiller units 20a and 20b, which are two chiller units, because the secondary thermal load Lo2 is “80 kW”. It can be judged. This is because the total capacity of the chiller units 20a and 20b is “90 kW”, which is higher than the secondary side thermal load Lo2 “80 kW” (80 kW <90 kW), and thus the minimum two chiller units 20a. , 20b is able to sufficiently cope with the current secondary-side heat load Lo2 while minimizing the total energy consumption. In this case, it is assumed that the condition that the total amount q2all of the secondary flow rate q2 is smaller than the total value Tr “257 L / min” of the rated flow rates Rf1 to Rf3 of the two chiller units 20a and 20b is satisfied. .

  In this state, the predetermined pumps are two primary pumps 44a and 44b corresponding to the chiller units 20a and 20b, respectively.

  Further, it is assumed that the total amount q2all of the secondary flow rate q2 changes to “286 L / min” during a predetermined time (Yes in S4). In this case, the total amount q2all “286L / min” of the secondary side flow rate q2 is the total value Tr “257L / R of the rated flow rates Rf1 to Rf2 of the predetermined pump being operated (specifically, the primary side pumps 44a and 44b). Since it is larger than min ″ (q2all> Tr, Yes in S5), the CPU 82 further operates the chiller unit 20c that is not operated and the primary side pump 44c corresponding thereto. In this state, there are three predetermined pumps, primary pumps 44a to 44c.

(4-2) Water Flow Minimum Control Operation in the Communication Pipe As the control operation performed in the optimum load factor maintenance control according to the present embodiment, the water flow minimum control in the communication pipe L5 other than the heat source number control operation described above. Operation.

  In the minimum flow rate control operation according to the present embodiment, by preventing water from flowing through the communication pipe L5, the total amount q2all of the secondary side flow rate q2 and the total amount q1all of the primary side flow rate q1 are equal (q2all = q1all), the control for adjusting the operation parameters including the load factor of the operating chiller units 20a to 20c is performed.

  For example, as described in the operation for controlling the number of heat sources, as an example in which the total amount q2all of the secondary flow rate q2 can be prevented from becoming larger than the total amount q1all of the primary flow rate q1 (q2all> q1all), Consider a combination in which the total amount q2all of the secondary flow rate q2 is “272 L / min” and the total amount q1all of the primary flow rate q1 is “300 L / min”. In this example, since the total amount q2all of the secondary flow rate q2 is smaller than the total amount q1all of the primary flow rate q1 (q2all <q1all), the flow rate of water required in the usage units 30a-30c is the chiller units 20a-20c. This is sufficient. However, there is a difference of “28 L / min” between the total amount q1all of the primary flow rate q1 and the total amount q2all of the secondary flow rate q2. Due to the configuration of the heat medium circuit 40 according to FIG. 1, the water of this difference flows out of the chiller units 20 a to 20 c and then flows into the use units 30 a to 30 c, not through the first feed header 42. It flows to the communication pipe L5 and is returned again to the chiller units 20a to 20c via the return header 41. Therefore, since the water flowing through the communication pipe L5 is not used in the utilization units 30a to 30c, the control for reducing the water flowing through the communication pipe L5 as much as possible, that is, the total amount q1all of the primary flow rate q1 and the secondary flow rate. It is preferable to perform control to make the total amount q2all of q2 equal. This is because the energy consumption of the primary pumps 44a to 44c and the chiller units 20a to 20c can be reduced.

  That is, when water is prevented from flowing into the communication pipe L5 under the condition that the total amount q2all of the secondary side flow rate q2 is not larger than the total amount q1all of the primary side flow rate q1 (q2all ≦ q1all), The total amount q1all is necessarily minimized. Then, the primary side pumps 44a to 44c for sending water to the units 20a to 20c on the side of the chiller units 20a to 20c that is the primary side can minimize the amount of energy consumption. Moreover, since water does not flow in the communication pipe L5, the flow rate of water in the communication pipe L5 is minimized. In this state, when the heat load processing system 10 is performing the cooling and dehumidifying operation or the cooling and humidifying operation, the water cooled by the chiller units 20a to 20c does not flow into the return header 41 via the communication pipe L5. Therefore, the temperature of the water flowing into the chiller units 20a to 20c from the return header 41, that is, the inlet temperatures Twin1 to Twin3 of the chiller units 20a to 20c is the highest. Therefore, the COP (Coefficient of Performance) of the chiller units 20a to 20c is increased.

  As described above, in order to minimize the flow rate of water flowing through the communication pipe L5, the CPU 82 performs PID control on each primary-side flow rate q1. In this state, if the total amount q2all of the secondary flow rate q2 (specifically, the detection result of the flow meter 48) changes during a predetermined time, the CPU 82 causes the primary pump that is currently operating to operate. Control to make the increase / decrease ratios of the predetermined pumps 44a to 44c equal to each other is performed. Specifically, as shown in the following equation (2), the CPU 82 sets the rated value of each predetermined pump with respect to the total value Tr of the rated flow rates Rf1 to Rf3 of all the predetermined pumps to the total amount q2all of the secondary side flow rate q2 at the present time. By multiplying the ratios of the flow rates Rf1 to R3, the increase / decrease ratio of each predetermined pump is made substantially the same.

上式（２）の“ＲｉｄＮ”は、各チラーユニット２０ａ〜２０ｃを流れる水の流量（即ち、各一次側流量ｑ１）を、所定ポンプ全てにおいて同じ比率だけ増減させた後の結果を表す。“ＲｆＮ”における“Ｎ”は、１〜３のいずれかの整数であって、どの所定ポンプ（つまりは、一次側ポンプ４４ａ〜４４ｃ）に対する定格流量Ｒｆ１〜Ｒｆ３であるのかを表している。

“RidN” in the above formula (2) represents the result after the flow rate of water flowing through each chiller unit 20a to 20c (that is, each primary flow rate q1) is increased or decreased by the same ratio in all the predetermined pumps. “N” in “RfN” is an integer of 1 to 3, and indicates the predetermined flow rate Rf1 to Rf3 for which predetermined pump (that is, the primary pumps 44a to 44c).

  As a specific example, the rated flow rates Rf1 to Rf3 of the primary side pumps 44a to 44c are “143L / min”, “114L / min”, and “86L / min” in order, and the total amount q2all of the secondary side flow rate q2 immediately after the change is “ It is assumed that it is 286 L / min ". And all the chiller units 20a-20c and the three primary side pumps 44a-44c corresponding to this operate | move, and each primary side pump 44a-44c circulates each rated flow rate Rf1-Rf3 water. And In such a state, the CPU 82 obtains the total value Tr of the rated flow rates Rf1 to Rf3 of all the primary pumps 44a to 44c as “343 L / min” by the calculation of “143 + 114 + 86”. The CPU 82 applies the total value Tr of the obtained rated flow rates Rf1 to Rf3 and the rated flow rates Rf1 to Rf3 of the primary pumps 44a to 44c, which are predetermined pumps, to the above equation (2), and the primary pumps 44a to 44c. The flow rates Rid1, Rid2, and Rid3 to be flowed by the primary pumps 44a to 44c after increasing / decreasing by the same ratio are obtained. More specifically, the flow rates Rid1 to Rid3 of the water to be caused to flow by the primary pumps 44a to 44c are obtained as in the following formulas (3) to (5).

上式（３）〜（５）に示されるように、各一次側ポンプ４４ａ〜４４ｃ（つまりは、所定ポンプ）が流すべき水の流量Ｒｉｄ１〜Ｒｉｄ３は、各定格流量Ｒｆ１〜Ｒｆ３に対して減少した値となっているが、各定格流量Ｒｆ１〜Ｒｆ３を１００％とした場合の流量Ｒｉｄ１〜Ｒｉｄ３の割合を表す増減比率は、いずれも約８３％となっている。このように、ここでは、各一次側ポンプ４４ａ〜４４ｃが各チラーユニット２０ａ〜２０ｃに流す水の流量の増減の度合いが、定格流量Ｒｆ１〜Ｒｆ３の比率と同じになるように制御される。

As shown in the above formulas (3) to (5), the flow rates Rid1 to Rid3 of the water that each primary pump 44a to 44c (that is, the predetermined pump) should flow are decreased with respect to the respective rated flow rates Rf1 to Rf3. However, the increase / decrease ratios representing the ratios of the flow rates Rid1 to Rid3 when the rated flow rates Rf1 to Rf3 are 100% are all about 83%. Thus, here, the degree of increase / decrease in the flow rate of the water flowing through each chiller unit 20a-20c by each primary pump 44a-44c is controlled to be the same as the ratio of the rated flow rates Rf1-Rf3.

  Next, the CPU 82 is a primary pump 44a that is a predetermined pump so that the water of the respective flow rates Rid1 to Rid1 determined in the above formulas (3) to (5) flows to the chiller units 20a to 20c. The inverter frequency of each of .about.44c is changed. Specifically, each primary flow rate q1 is proportional to the inverter frequency of the primary pumps 44a to 44c corresponding to each of the chiller units 20a to 20c. Therefore, the CPU 82 sets the inverter frequencies of the primary pumps 44a to 44c, which are predetermined pumps, to the same increase / decrease ratio according to the flow rates Rid1 to Rid3 of the water that the primary pumps 44a to 44c should flow to the chiller units 20a to 20c. Control to change. That is, as described above, when the increase / decrease ratio of water is about 83%, the CPU 82 performs control so that the inverter frequency of each of the primary pumps 44a to 44c is decreased to about 83%.

  In addition, as for the inverter frequency of each primary side pump 44a-44c, the desired inverter frequency based on the increase / decrease ratio is first determined, and the differential pressure between the return header 41 and the first feed header 42 becomes the desired inverter frequency. Thus, it is increased or decreased by PID control.

(4-3) Capability Compensation Control Operation The control operation performed in the optimum load factor maintenance control according to the present embodiment includes a capability compensation control operation in addition to the above-described heat source number control operation and water flow rate minimum control operation. .

  The capability compensation control operation according to the present embodiment is that the target value exceeds the limit in terms of capability with respect to the target value of the flow rate of water imposed on each of the chiller units 20a to 20c and the primary pumps 44a to 44c. If there is a combination of the chiller units 20a to 20 and the primary side pumps 44a to 44c, the target value of the flow rate of the water that is insufficient in the combination is replaced with the other chiller units 20a to 20c and the primary side pump 44a. This is the control to compensate by ~ 44c.

  Specifically, the CPU 82 has a flow rate of water to be circulated (for example, each chiller unit 20a described above) in two or more predetermined pumps (specifically, primary pumps 44a to 44c that are operating). When there is a first predetermined pump in which the target values that are the flow rates Rid1 to Rid3) of the water to flow to 20c exceed the rated flow rates Rf1 to Rf3, the difference between the rated flow rates Rf1 to Rf3 and the target value is the second. The increase / decrease ratio of each predetermined pump is adjusted so as to be compensated by the predetermined pump. Here, the second predetermined pump refers to a first predetermined pump that is a predetermined pump whose target value has exceeded the limit in capacity among the predetermined pumps that are the primary pumps 44a to 44c that are operating. The remaining predetermined pumps are excluded.

  Hereinafter, the capacity compensation control will be described in detail. FIG. 10 is a graph showing the capacity characteristics of the chiller units 20a to 20c with the horizontal axis representing capacity and the vertical axis representing COP. In FIG. 10, the capability characteristic of the chiller unit 20a is represented by a one-dot chain line, the capability characteristic of the chiller unit 20b is represented by a dotted line, and the capability characteristic of the chiller unit 20c is represented by a solid line. As shown in FIG. 10, in the present embodiment, a case where the graphs representing the performance characteristics of the chiller units 20 a to 20 c have the same peak and draw the same curve is taken as an example. This indicates that the chiller units 20a to 20c all have the same capability characteristics. However, as already explained, since the optimum load factors of the chiller units 20a to 20c are different from each other, the optimum values of the abilities are also different. In FIG. 10, as an example, the optimum values of the capacities of the chiller units 20a to 20c are “50 kW”, “40 kW”, and “30 kW” in order.

  Here, in the case of FIG. 10, the secondary load Lo2, that is, the total value of the capacities of the utilization units 30a to 30c is “80 kW”, and the total amount q2all of the secondary flow rate q2 in this case is “286 L / Assume that min ”. It is assumed that the rated flow rates Rf1 to Rf3 of the primary pumps 44a to 44c are “143L / min”, “114L / min”, and “86L / min” in order.

  Since each chiller unit 20a-20c has the same capability characteristic, the capability required in each chiller unit 20a-20c is 3 minutes of the total value “80 kW” of the usage units 30a-30c. 1, that is, about “26.7 kW” (80 / 3≈26.7). Then, since the capacity | capacitance required for each chiller unit 20a-20c will be "26.7 kW", the flow volume of the water (the primary side pump 44a-44c which is a predetermined pump should flow through each chiller unit 20a-20c ( In other words, the target value of the water flow rate) is one third of the total amount q2all “286 L / min” of the secondary side flow rate q2, that is, about “95 L / min” (286 / 3≈95).

  However, since the rated flow rate Rf3 of the primary side pump 44c corresponding to the chiller unit 20c is “86 L / min”, the target value “95 L / min”, which is the flow rate of water that the primary side pump 44 c should flow to the chiller unit 20 c. Exceeds the rated flow rate Rf3 (86 <95). In this case, the primary pump 44c corresponds to a first predetermined pump. Therefore, the target value of the flow rate of water that the primary pump 44c can flow to the chiller unit 20c is the upper limit value of the rated flow rate Rf3 “86 L / min”, and the rated flow rate Rf3 “86 L / min” and the target value. The difference “9 L / min” from “95 L / min” (95−86 = 9) needs to be compensated on the remaining chiller units 20 a and 20 b side. In this case, the primary pumps 44a and 44b corresponding to the chiller units 20a and 20b correspond to the second predetermined pump.

  Therefore, as shown in the following equation (6), the CPU 82 determines the rated flow rate Rf3 “86 L / min” of the primary pump 44 c (ie, the first predetermined pump) from the total amount q2all “286 L / min” of the secondary flow rate q2. "And subtracting the subtraction result by the number" 2 "of the second predetermined pumps, the primary flow rate of water to be supplied to the chiller units 20a and 20b by the primary pumps 44a and 44b is" 100L / Recalculate min ”.

次いで、ＣＰＵ８２は、次式（７）（８）に示されるように、上式（６）の算出結果を、第２所定ポンプである一次側ポンプ４４ａ，４４ｂそれぞれの定格流量Ｒｆ１，Ｒｆ２で除算することにより、各一次側ポンプ４４ａ，４４ｂそれぞれがチラーユニット２０ａ，２０ｂに流す水の流量の増減比率を変更する。

Next, as shown in the following formulas (7) and (8), the CPU 82 divides the calculation result of the above formula (6) by the rated flow rates Rf1 and Rf2 of the primary side pumps 44a and 44b that are the second predetermined pumps. By doing so, each primary side pump 44a, 44b changes the increase / decrease ratio of the flow volume of the water which flows into chiller unit 20a, 20b, respectively.

増減比率の変更後に二次側流量ｑ２の総量ｑ２ａｌｌが再び変化した場合、ＣＰＵ８２は、次回の各チラーユニット２０ａ〜２０ｃの負荷率の調整までの間、二次側流量ｑ２の増減に応じて、上述したチラーユニット２０ａ，２０ｂに流す水の流量の増減比率の割合が一定となるように、各一次側ポンプ４４ａ，４４ｂのインバータ周波数を変化させる制御を行う。

When the total amount q2all of the secondary side flow rate q2 changes again after the change of the increase / decrease ratio, the CPU 82 increases or decreases the secondary side flow rate q2 until the next adjustment of the load factor of each chiller unit 20a to 20c. Control is performed to change the inverter frequency of each primary pump 44a, 44b so that the ratio of the increase / decrease ratio of the flow rate of the water flowing through the chiller units 20a, 20b is constant.

(5) Features (5-1)
In the present embodiment, the load factor of each of the chiller units 20a to 20c is set every predetermined time so that the total energy consumption of the entire thermal load processing system 10 including the chiller units 20a to 20c and the primary pumps 44a to 44c is reduced. Control to adjust is performed. In particular, when the total amount q2all of the secondary-side flow rate q2 changes during a predetermined time, the increase / decrease ratio of the flow rate of water circulated by each of the predetermined pumps that are at least two primary-side pumps 44a to 44c is substantially equal to each other. In addition, control for changing the inverter frequency of each of the predetermined pumps is performed. Then, each inverter frequency of the predetermined pump changes by the same ratio as the increase / decrease ratio of the total amount q2all of the secondary flow rate q2, and the flow rate of water flowing through each of the chiller units 20a to 20c corresponding to the predetermined pump (that is, Each primary flow rate q1) changes by the same rate. Thereby, the load factor of each chiller unit 20a-20c related to each primary flow rate q1 can be changed to a value that can be said to be appropriate for the total amount q2all of the changed secondary flow rate q2. Therefore, even if the total amount q2all of the secondary flow rate q2 changes during a predetermined time, the thermal load processing system 10 appropriately performs energy saving control using appropriate load factors of the chiller units 20a to 20c. Is possible.

  In addition, an operation parameter setting operation including the load factor of each of the chiller units 20a to 20c is performed every predetermined time, and every time this setting operation is performed, the total amount q1all of the primary flow rate q1 changes. Then, the temperature of the water circulating in the heat medium circuit 40 and the secondary water supply pressure change discontinuously, and this change becomes a disturbance factor of the temperature control and humidity control of the usage units 30a to 30c.

  However, in this embodiment, since the inverter frequency of each predetermined pump is changed so that the increase / decrease ratio of each primary flow rate q1 circulated by each predetermined pump becomes equal to each other, the capacity of each chiller unit 20a to 20c with respect to the load The ratio is almost constant. Accordingly, since the temperature of the water and the water supply pressure on the secondary side change continuously, the temperature control and humidity control of the usage units 30a to 30c are stabilized.

(5-2)
Here, the predetermined pump mentioned above is the primary side pumps 44a to 44c corresponding to the operating chiller units 20a to 20c among the primary side pumps 44a to 44c. Therefore, when the secondary flow rate q2 changes during a predetermined time, the inverter frequencies of the primary pumps 44a to 44c corresponding to the operating chiller units 20a to 20c change.

(5-3)
In the thermal load processing system 10 according to the present embodiment, so-called heat source number control is performed. In the control of the number of heat sources, the number of chiller units 20a to 20c to be operated is determined based on the total load value of all the usage units 30a to 30c that are the secondary side heat load Lo. In the control of the number of heat sources, the total amount q2all of the secondary side flow rate q2 is the total value of the rated flow rates Rf1 to Rf3 of the predetermined pump (that is, the primary side pumps 44a to 44c corresponding to the operating chiller units 20a to 20c). When larger than Tr (q2all> Tr), control is performed to increase the number of chiller units 20a to 20c to be operated. Thereby, the required number of chiller units 20a to 20c can be operated while suppressing the total energy consumption as much as possible.

(5-4)
Moreover, the thermal load processing system 10 according to the present embodiment includes a communication pipe L5 as shown in FIG. The communication pipe L5 connects the inlet side and the outlet side of all of the plurality of chiller units 20a to 20c via the return header 41 and the first feed header 42. In the heat load treatment system 10, the water does not flow through the communication pipe L5, so that the total amount q2all of the secondary flow rate q2 and the total amount q1all of the primary flow rate q1 are equal (q2all = q1all). Control which adjusts the operation parameter including the load factor of units 20a-20c is performed. As a result, the total amount q1all of the primary flow rate q1 is minimized, and the amount of energy consumed by the primary pumps 44a to 44c is minimized. Furthermore, since water does not flow through the communication pipe L5, when the heat load treatment system 10 performs the cooling / dehumidifying operation or the cooling / humidifying operation, the inlet temperatures Twin-1 to Twin3 of the chiller units 20a to 20c are the highest, COP of chiller units 20a-20c improves.

(5-5)
Furthermore, in the thermal load processing system 10 according to the present embodiment, as shown in the above formulas (3) to (5), the total flow rate q2all of the secondary-side flow rate q2 is equal to the rated flow rates Rf1 to Rf3 of all the predetermined pumps. By multiplying the ratios of the rated flow rates Rf1 to Rf3 of the predetermined pumps with respect to the total value Tr, control for making the increase / decrease ratios of the predetermined pumps substantially equal to each other is performed. Thereby, the thermal load processing system 10 can ensure that the increase / decrease ratio of each predetermined pump is substantially equal.

(5-6)
Moreover, in the thermal load processing system 10 according to the present embodiment, among two or more predetermined pumps, the flow rate of water that each of the predetermined pumps should flow to the chiller units 20a to 20c (that is, the target value of the flow rate of water). When there is a first predetermined pump that exceeds the rated flow rates Rf1 to Rf3, each predetermined flow rate is compensated by a second predetermined pump that is another predetermined pump so that the difference between the rated flow rates Rf1 to Rf3 and the target value is compensated. Control for adjusting the increase / decrease ratio of the pump is performed. Thus, even if there is a first predetermined pump whose target value exceeds the rated flow rates Rf1 to Rf3, water for the total value of the target value in each predetermined pump is reliably circulated in the heat medium circuit 40. Become.

(6) Modification (6-1) Modification A
In the above-described embodiment, the detailed control operation performed in the optimum load factor maintenance control is described as the heat source number control operation, the water flow minimum control operation in the communication pipe L5, and the capacity compensation operation. However, in the heat load processing system according to the present invention, when the total amount q2all of the secondary side flow rate q2 changes during a predetermined time, each of the predetermined pumps that are at least two primary side pumps among the primary side pumps 44a to 44c. Since it is only necessary to control the inverter frequency so that the increase / decrease ratio of the flow rate of water circulated by each predetermined pump is substantially equal to each other, the heat source number control operation and the capacity compensation control operation are not essential. Therefore, either of the heat source number and the capacity compensation control operation may not be performed, or any one of the operations may be performed.

(6-2) Modification B
In the above embodiment, the case where the thermal load processing system 10 includes the communication pipe L5 has been described as illustrated in FIG. In addition, in the above-described embodiment, it has been described that the control for making the increase / decrease ratio of each predetermined pump substantially the same is performed based on the above equation (2).

  However, the above equation (2) is an example. Therefore, when the total amount q2all of the secondary side flow rate q2 changes during a predetermined time, the control for changing the inverter frequency so that the increase / decrease ratio in each predetermined pump becomes substantially equal is performed by using an expression other than the above expression (2). It may be realized using.

(6-3) Modification C
In the said embodiment, as shown in FIG. 1, the case where there were three utilization units 30a-30c was demonstrated. However, even if the thermal load processing system according to the present invention includes a usage unit, the number of usage units may be one or more.

  When the number of usage units is one, the flow meter 48 represents the secondary flow rate q2 of the water flowing to one usage unit. In the above-described embodiment, all the parts indicated as “total amount q2all of secondary flow rate q2” are replaced with “secondary flow rate q2”.

  Moreover, in the said embodiment, as shown in FIG. 1, the case where the secondary pumps 46 and 47 were two units was demonstrated. However, in the thermal load processing system according to the present invention, even if a secondary pump is provided, the number of secondary pumps may be one or plural.

(6-4) Modification D
In the above embodiment, it has been described that the primary pumps 44a to 44c and the secondary pumps 46 and 47 are both inverter type pumps. However, in the present invention, the primary pumps 44a to 44c need to be inverter pumps, but the secondary pumps 46 and 47 may be fixed capacity pumps instead of inverter pumps.

(6-5) Modification E
In the above embodiment, the case where the total amount q2all of the flow rate of the water that has flowed through the use units 30a to 30c is obtained by measurement by the flow meter 48 has been described. However, the total amount q2all of the flow rate of the water that has flowed through the use units 30a to 30c may be estimated and not actually measured. As an estimation method of the total amount q2all of the flow rate of the water that has flowed through the usage units 30a to 30c, for example, a method that is obtained by the inverter frequency of the secondary pumps 46 and 47, or the like can be given. In this case, the heat medium circuit 40 need not be provided with the flow meter 48.

  Further, the heat medium circulating in the heat medium circuit 40 may be other than water.

DESCRIPTION OF SYMBOLS 10 Thermal load processing system 20 Chiller unit group 20a-20c Chiller unit (heat source machine)
21 refrigerant circuit 22 compressor 23 radiator 24 chiller side expansion valve 25 evaporator 30 use unit group 30a-30c use unit 31a-31c casing 32a-32c use side valve 33a-33c use side heat exchanger 34a-34c electric heater 35a -35c Watering type humidifiers 36a-36c Blower 40 Heat medium circuit 41 Return header 42 First feed header 43 Second feed header 44a-44c Primary side pump (pump)
45 Bypass valves 46, 47 Secondary pump 48 Flow meter 49 Power meter 60 Heat radiation circuit 61 Water pump 70 Cooling tower 80 System controller (control unit)
81 Memory 82 CPU
L1 to L4 Connecting piping (first piping)
L5 communication pipe (second pipe)
T1, T2, T3a to T3c, T4a to T4c Temperature detection sensors Twin1 to Twin3 Inlet temperature of each chiller unit Twout1 to Twout3 Outlet temperature of each chiller unit q1 Primary side flow rate q2 Secondary side flow rate q1all Primary side flow rate q2all Secondary Total flow amount Lo2 Secondary thermal load Rf1 to Rf3 Rated flow rate Tr of a given pump Total flow rate Rid of all specified pumps Rid The flow rate of water that each primary pump should flow when the increase / decrease ratio is the same

JP 2003-106731 A JP 2009-14300 A

Claims (6)

A plurality of heat source units (20a to 20c) that heat or cool the heat medium and have different optimum values of the load factors;
First pipes (L1 to L4) that connect each of the plurality of heat source units and use units (30a to 30c) that use the heat medium in an annular shape,
An inverter type that is provided in plural on the first pipe so as to correspond to each of the plurality of heat source machines, and circulates the heat medium flowing in the first pipe between the heat source machine and the utilization unit. Pumps (44a-44c),
A control unit (80) for performing energy saving control ,
In the energy saving control, the control unit
A load factor adjustment control that adjusts the load factor of each of the heat source units at predetermined time intervals so that at least the total energy consumption consumed by the heat source unit and the pump is reduced ;
When the flow rate of the heat medium flowing through the utilization unit changes during the predetermined time, each predetermined pump circulates the inverter frequency of each of the predetermined pumps that are at least two of the plurality of pumps. A load factor maintaining control for changing the rate of increase / decrease in the flow rate of the heat medium to be substantially equal to each other ;
I do,
Thermal load treatment system (10).
The predetermined pump is the pump corresponding to the operating heat source machine among the pumps.
The thermal load processing system (10) according to claim 1. The control unit (80)
Based on the load of the utilization unit, determine the number of heat source machines to be operated,
If the flow rate of the heat medium flowing through the utilization unit is greater than the total value of the rated flow rates of the predetermined pump, increase the number of heat source devices to be operated;
The thermal load processing system (10) according to claim 2. A second pipe (L5) connecting the inlet side and the outlet side of all of the plurality of heat source units,
Further comprising
The control unit (80) is configured such that the flow rate of the heat medium flowing through the utilization unit and the flow rate of the heat medium flowing through each of the plurality of heat source devices when the heat medium does not flow in the second pipe. To control at least the load factor of each of the heat source units so that
The heat load processing system (10) according to claim 2 or 3. The control unit (80) multiplies the flow rate of the heat medium flowing through the utilization unit by the ratio of the rated flow rate of each predetermined pump to the total value of the rated flow rates of all the predetermined pumps. Making the increase / decrease ratios substantially equal to each other,
The thermal load processing system (10) according to claim 4. When there is a first predetermined pump in which the flow rate of the heat medium to be circulated exceeds the rated flow rate in the two or more predetermined pumps, the control unit (80) is configured to circulate with the rated flow rate. Adjusting the increase / decrease ratio of each of the predetermined pumps so that the difference from the flow rate of the heat medium is compensated by the remaining second predetermined pumps excluding the first predetermined pump from the predetermined pumps;
The thermal load processing system (10) according to any one of claims 2 to 5.

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