JP6812283B2 - Heat source control system, control method of heat source control system and arithmetic unit - Google Patents

Description

The present invention relates to a heat source control system for air conditioning equipment, a control method for the heat source control system, and an arithmetic unit.

In the heat source control system in air conditioning equipment, the energy consumption of the primary side equipment (refrigerator, primary chilled water pump, cooling tower, cooling water pump) on the heat source side and the secondary side equipment on the air conditioning load side (refrigerator, primary chilled water pump, cooling tower, cooling water pump) Control is required to minimize the energy consumption of the entire air conditioning system, which is the sum of the energy consumption of the air conditioner (secondary chilled water pump).

Here, in the control of the equipment on the primary side of the heat source control system, the flow rate of the primary chilled water for each refrigerator is controlled so that the energy consumption of the equipment on the primary side is reduced.

Further, regarding the equipment on the secondary side, the energy consumption of the entire air conditioning system can be controlled by controlling the secondary chilled water flow rate and the secondary chilled water forward temperature. Regarding the secondary chilled water flow rate, control is performed to keep the discharge pressure constant and to keep the terminal differential pressure constant. Further, for example, if the secondary chilled water forward temperature is raised, the chilled water outlet temperature of the chiller on the primary side can be raised, so that the energy consumption in the chiller is suppressed. Therefore, the setting of the secondary chilled water forward temperature in the heat source control system is a major factor in determining the energy consumption of the heat source machine and the air conditioning system as a whole. In particular, in the intermediate period and winter, the air conditioning load can be processed even if the secondary chilled water forward temperature is raised above the set value, so the secondary chilled water forward temperature may be raised to save energy.

By the way, the energy consumption of the equipment on the secondary side changes according to the fluctuation of the heat load based on the outside air condition, the time, the indoor usage condition, and the like. Therefore, it is difficult to obtain the optimum secondary chilled water forward temperature that simultaneously satisfies the comfort and energy saving of the room to be air-conditioned by physical calculation. For example, even if the secondary cold water forward temperature is set to minimize the energy consumption of the secondary equipment, if the secondary cold water forward temperature is a temperature at which the heat load cannot be processed, the room temperature Will rise, and the comfort of the room will be impaired.

In the control of a general heat source control system, the current situation is that the operator manually sets the secondary chilled water forward temperature, which is considered to be able to maintain comfort and energy saving, based on personal intuition and experience. .. Therefore, in the actual control of the heat source control system, it is often the case that the optimum secondary chilled water forward temperature is not always set for the state of the air conditioning load. Further, when changing the setting of the secondary chilled water forward temperature, the operator often does not know how much the temperature setting should be changed.

It has also been proposed to obtain operating parameters based on a model using a response surface methodology (RSM-S: Response Surface Method by Spline) using a multivariable spline in the control of an air conditioning system (for example, Patent Document 1). -3).

Japanese Patent No. 4402645 Japanese Patent No. 5860237 Japanese Patent No. 5320128

However, in all the methods of the prior art, since the energy consumption of the primary side device and the secondary side device are collectively statistically analyzed, the model of the response curved surface reflecting various parameters has a very complicated shape. turn into. Therefore, the method of the prior art is not practical because the calculation process for obtaining the optimum solution from the model of the response curved surface becomes very complicated.

An object of the present invention is a heat source control system and heat source control that can minimize the energy consumption of the entire air conditioning system and determine the secondary chilled water forward temperature that does not impair the comfort of the room by a simpler method than before. The purpose is to provide a system control method and an arithmetic unit.

The heat source control system according to one aspect of the present invention is the refrigerating machine via a refrigerating machine, a first outgoing header connected to the chilled water outlet side of the refrigerating machine by a chilled water primary outgoing pipe, and a primary chilled water pump. The return header connected to the chilled water inlet side by the chilled water primary return pipe, the bypass pipe connecting the first forward header and the return header, and the secondary chilled water pump go to the first forward header. The second forward header connected by the header pipe, the air conditioning load connected between the second forward header and the return header via the cold water secondary forward pipe and the cold water secondary return pipe, and the second forward pipe. A secondary forward thermometer arranged in the header or the cold water secondary return pipe to measure the secondary cold water forward temperature, and a secondary cold water return temperature arranged in the return header or the cold water secondary return pipe to measure the secondary cold water return temperature 2 A secondary return thermometer, a secondary flow meter arranged in the cold water secondary return pipe to measure the secondary chilled water flow rate, an outside temperature / humidity sensor for measuring the outside air / wet bulb temperature, and a target of the secondary cold water forward temperature. A calculation device for obtaining a value and a control device for controlling the refrigerator, the primary chilled water pump, and the secondary chilled water pump based on the target value of the secondary chilled water forward temperature are provided.

The arithmetic unit has a secondary load heat quantity calculation unit, a heat source primary side processing unit, a heat source secondary processing unit, and a target value calculation unit. The secondary load heat amount calculation unit calculates the secondary load heat amount using the measured value of the secondary chilled water flow rate, the measured value of the secondary chilled water return temperature, and the measured value of the secondary chilled water forward temperature. The heat source primary side processing unit uses the measured value of the secondary chilled water flow rate and the measured value of the outside air wet-bulb temperature to generate the energy consumption of the heat source primary side and the secondary side, which is the energy consumption of the equipment on the primary side. A plurality of sets of combinations with the chilled water forward temperature are calculated, and based on the calculation result, a first function showing the correlation between the heat source primary energy consumption and the secondary chilled water forward temperature is generated. The heat source secondary processing unit determines the energy consumption of the secondary chilled water pump and the secondary chilled water forward temperature during system operation, which are extracted based on the measured values of the secondary load heat quantity and the outside air wet-bulb temperature. Based on the distribution of the combinations, a second function showing the correlation between the energy consumption of the secondary chilled water pump and the secondary chilled water forward temperature is generated. The target value calculation unit synthesizes the first function and the second function to generate an objective function showing the correlation between the energy consumption of the entire system and the secondary cold water forward temperature, and the objective function is used. The secondary chilled water forward temperature at which the energy consumption of the entire system is minimized is calculated, and the target value of the secondary chilled water forward temperature is determined based on the calculated secondary chilled water forward temperature.

Further, the heat source control system is a distribution of a combination of the energy consumption of the air conditioning load and the secondary cold water forward temperature during system operation, which is extracted based on the measured values of the secondary load heat quantity and the outside air wet-bulb temperature. Based on the above, an air conditioning load processing unit that generates a third function indicating the correlation between the energy consumption of the air conditioning load and the secondary cold water forward temperature may be further provided. Then, the target value calculation unit may generate the objective function by synthesizing the first function, the second function, and the third function.

Further, the heat source control system further stores a plurality of combinations of the secondary load heat amount, the outside air wet-bulb temperature, the energy consumption of the secondary chilled water pump, and the secondary chilled water forward temperature during system operation. You may have it. Then, the heat source secondary processing unit includes the energy consumption of the secondary chilled water pump and the energy consumption of the secondary chilled water pump corresponding to the conditions of the secondary load heat amount calculated by the secondary load heat amount calculation unit and the measured values of the outside air wet-bulb temperature. A plurality of combinations with the secondary cold water forward temperature may be extracted from the storage device.

Further, the heat source control system further includes a storage device that stores a plurality of combinations of the secondary load heat amount, the outside air wet-bulb temperature, the energy consumption amount of the air conditioning load, and the secondary cold water forward temperature during system operation. You may. Then, the air conditioning load processing unit determines the energy consumption of the air conditioning load and the secondary cold water forward corresponding to the conditions of the secondary load heat amount calculated by the secondary load heat amount calculation unit and the measured values of the outside air wet-bulb temperature. A plurality of combinations with temperature may be extracted from the storage device.

Here, the features of the heat source control system according to one aspect of the present invention can also be expressed in the form of a control method of the heat source control system and an arithmetic unit for calculating the target value of the secondary chilled water forward temperature of the heat source control system. .. Further, the configuration of the heat source control system according to one aspect of the present invention is not limited to the case of the primary secondary pump system, and can be applied to the case of the primary pump system.

According to one aspect of the present invention, the energy consumption of the entire air conditioning system can be minimized, and the secondary cold water forward temperature that does not impair the comfort of the room can be determined by a simpler method as compared with the conventional method.

The figure which shows the configuration example of the heat source control system of the primary secondary pump system in one Embodiment. Diagram showing an example of a database of a data collection server The figure which shows the example of the control flow about the real-time controller of one Embodiment. The figure which shows the calculation processing example in the calculation server in the heat source control system of one Embodiment (A): A graph showing an example of the correspondence between the heat source primary energy consumption E1_HS1 and the secondary chilled water forward temperature Tcs2, (b): a diagram in which the first function F1 is plotted in FIG. 5 (a). (A): A graph showing an example of the correspondence between the energy consumption EP_CP2 of the secondary chilled water pump and the secondary chilled water forward temperature Tcs2, (b): a diagram in which the second function F2 is plotted in FIG. 6 (a). (A): A graph showing an example of the correspondence between the energy consumption E1_AHU of the air conditioning load and the secondary chilled water forward temperature Tcs2, (b): a diagram in which the third function F3 is plotted in FIG. 7 (a). Graph showing functions F1 to F4 The figure which shows the configuration example of the heat source control system of the primary pump type in another embodiment. The figure which shows the calculation processing example in the calculation server in the heat source control system of another embodiment.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.

The heat source control system of the air conditioning equipment may be either a primary pump system or a primary secondary pump system. Hereinafter, the configuration of the primary and secondary pump type heat source control system and the configuration of the primary pump type heat source control system will be described. In the following description, a case where cold water is used as a cold heat medium and a refrigerator is used as a heat source will be described.

<Configuration example of primary / secondary pump type heat source control system>
FIG. 1 shows a configuration example of a primary / secondary pump type heat source control system 100 according to an embodiment. In the primary / secondary pump type heat source control system 100, the lifts on the refrigerator side and the air conditioning load side are shared by two types of pumps with the forward header 102 and the return header 103 as boundaries. Therefore, the heat source control system has a plurality of primary chilled water pumps 12 and secondary chilled water pumps 85a and 85b provided for each of the plurality of refrigerators (heat source machine R) 11. The primary chilled water pump 12 sends out the secondary chilled water that is heat-exchanged by the air-conditioning load of the air conditioner 104 or the like, raises the temperature, and returns to the return header 103 as the primary chilled water via the refrigerator 11. When the primary chilled water pump 12 circulates the primary chilled water from the return header 103 to the refrigerator and from the refrigerator 11 to the forward header 102, the piping resistance to the forward header 102 and the return header 103 and the water pressure loss of the refrigerator 11 Take charge of the total with the minutes as the lift. Further, the secondary chilled water pumps 85a and 85b send the primary chilled water sent from the refrigerator 11 to the forward header 102 as the secondary chilled water with respect to the air conditioning load. The secondary chilled water pump is responsible for the sum of the pipe resistance of the chilled water secondary forward pipe 39 and the chilled water secondary return pipe 41 and the water pressure loss of the heat exchanger portion of the air conditioning load as the head.

The heat source control system 100 shown in FIG. 1 includes n single heat source units 101 (1) to 101 (n), a forward header 102, a return header 103, an air conditioner (AHU) 104, a real-time controller 105, and the like. It has an outside air temperature / humidity sensor 106 for measuring the outside air wet-bulb temperature, a data collection server 200, and a calculation server 300. Here, the outside air temperature / humidity sensor 106 outputs the measured outside air wet-bulb temperature to the real-time controller 105 as a signal. In the example of FIG. 1, only one air conditioner (AHU) 104 is shown for simplicity, but the number of air conditioners (AHU) 104 as an air conditioning load is a plurality. Further, the real-time controller 105, the data collection server 200, and the arithmetic server 300 are connected to each other via a known wired or wireless network 400.

The single heat source unit 101 is a set of constituent devices related to one refrigerator, and includes four devices including a refrigerator (heat source machine R), a primary chilled water pump, a cooling tower, and a cooling water pump. .. The n single heat source units 101 shown in FIG. 1 have different performances of each element (for example, differences depending on the type of refrigerator, differences depending on the heat transfer area of the cooling tower, etc.), but the basic configuration is as follows. Same or similar. Here, the configuration of one single heat source unit 101 (n) will be described, and duplicate description of each single heat source unit 101 will be omitted. As described above, the single heat source unit 101 (n) includes a refrigerator (heat source machine R) 11, a primary chilled water pump 12, a cooling tower 13, and a cooling water pump 14.

The refrigerator (heat source machine R) 11 is, for example, a turbo chiller, an inverter turbo chiller, an absorption chiller, a cold / hot water generator, a screw chiller, a heat pump chiller, or the like. If the partial load characteristics can be confirmed, an exhaust heat recovery type refrigerator can also be used as the refrigerator (heat source machine R) 11.

Each of the refrigerators (heat source machine R) 11 in the n single heat source units 101 is connected in parallel to the forward header 102 by the cold water primary forward pipe 15, and each is returned by the cold water primary return pipe 16. It is connected in parallel to the header 103. Here, the cold water primary forward pipe 15 is a pipe that sends cold water cooled (called freezing) by the heat source machine R to the forward header 102 on the primary side of the cold water. Further, the cold water primary return pipe 16 returns to the return header 103 after heat is exchanged by the air conditioner 104 on the primary side of the cold water and the temperature rises, and the combined return cold water is sent from the return header 103 to the heat source machine R. It is a pipe to be used.

Information on the chilled water outlet temperature SP (Set Point) is input from the real-time controller 105 to the refrigerator (heat source machine R) 11. Information indicating the heat source operating state is output from the refrigerator (heat source machine R) 11 to the real-time controller 105, respectively.

The chilled water primary forward pipe 15 is provided with a temperature sensor 17 for measuring the chilled water outlet temperature of the refrigerator (heat source machine R) 11. The temperature PV (Process Value: measured value) of the temperature sensor 17 is output to the real-time controller 105.

In the chilled water primary return pipe 16, the flow meter 18, the primary chilled water pump 12, and the chilled water inlet temperature of the chiller (heat source machine R) are measured from the return header 103 toward the chiller (heat source machine R) 11. Each temperature sensor 19 is provided. The temperature PV of the temperature sensor 19 is output to the real-time controller 105. Further, the flow rate PV of the flow meter 18 is output to the real-time controller 105. The primary chilled water pump is equipped with an inverter (INV) as a power source for the pump motor. The rotation speed of the primary chilled water pump 12 is variable by frequency control of the power supply by the inverter (INV) according to the instruction of the real-time controller 105.

Further, the refrigerator (heat source machine R) 11 is provided with an annular cooling water pipe 21 connected so that cooling water can be taken in and out of the inlet and outlet of a heat exchanger such as a condenser that exchanges heat with exhaust heat. .. Then, the cooling tower 13 is connected to the heat source machine R via the cooling water pump 14 by the annular cooling water pipe 21. Due to the conveying power of the cooling water pump 14, the cooling water whose temperature has risen due to the exhaust heat of the heat source machine R is sent from the heat source machine R to the cooling tower 13 through the cooling water pipe 21. Further, due to the conveying power of the cooling water pump 14, the cooling water pipe 21 is cooled by exchanging heat between the outside air and the cooling water by the cooling tower fan of the cooling tower 13 to release heat from the cooling tower 13. Water is sent to the heat source machine R through.

The cooling tower 13 cools the cooling water whose temperature has risen due to the exhaust heat of the refrigerator (heat source machine R) 11 by direct contact with the outside air or indirect contact with the outside air by the cooling tower fan. The cooling water pump 14 sends the cooling water cooled by the cooling tower 13 to the refrigerator (heat source machine R) 11. The cooling tower fan and the cooling water pump 14 of the cooling tower 13 each include an inverter (INV) as a power source for each motor. The rotation speeds of the cooling tower fan and the cooling water pump 14 of the cooling tower 13 are variable by frequency control of the power supply by the inverter (INV) according to the instruction of the real-time controller 105.

Further, the forward header 102 and the return header 103 are connected via a bypass path 31.

As described above, in the heat source control system 100 shown in FIG. 1, n single heat source units 101, the forward header 102, the return header 103, the cold water primary forward pipe 15 and the cold water primary return pipe 16 connecting them are connected. And the bypass path 31 constitute the primary side of the heat source.

On the other hand, in the heat source control system 100 shown in FIG. 1, the second forward header 83 is arranged on the downstream side of the forward header 102 with the secondary chilled water pumps 85a and 85b arranged in parallel on the secondary side of the heat source. The outbound header 102 and the second outbound header 83 are connected to each other via the secondary chilled water pumps 85a and 85b by a short pipe of the cold water secondary outbound pipe. Further, a bypass pipeline 87 used for pressure control of cold water sent to the air conditioning load is connected between the forward header 102 and the second forward header 83. The rotation speeds of the secondary chilled water pumps 85a and 85b are variable by frequency control of the power supply by the inverter (INV).

Between the second forward header 83 and the return header 103, there is a cold water secondary forward pipe 39 connecting the second forward header 83 and the air conditioner (AHU) 104, and the air conditioner (AHU) 104 and the return header. A cold water secondary return pipe 41 that connects to the 103 is provided. Here, the cold water secondary forward pipe 39 is a pipe that sends cold water frozen by the heat source machine R from the second forward header 83 to the air conditioner 104 on the secondary side of the cold water. The cold water secondary forward pipe 39 is provided with a temperature sensor 43 that measures the temperature of water sent to the air conditioning load in which a plurality of air conditioners 104 are assembled. Further, the cold water secondary return pipe 41 is a pipe that sends cold water whose temperature has risen due to heat exchange by the air conditioner 104 from the air conditioner 104 to the return header 103 on the secondary side of the cold water. The chilled water secondary return pipe 41 is provided with a temperature sensor 51 for measuring the temperature of chilled water returning to the return header 103 after heat exchange with an air conditioning load in which a plurality of air conditioners 104 are combined, and a flow meter 53. The measured values of the temperature sensors 43 and 51 and the flow meter 53 are output to the real-time controller.

As described above, in the heat source control system 100 shown in FIG. 1, the forward header 102, the return header 103, the second forward header 83, the air conditioner (AHU) 104, and the piping connecting these are used to secondary the heat source. The side is configured.

The real-time controller 105 is an example of a control device. For example, a main device constituting a hardware uses a programmable automation controller (PAC), which is a PC-based controller having an open development environment. The real-time controller 105 comprehensively controls the operation of the heat source control system 100 by executing a program. For example, the real-time controller 105 controls the number of heat sources that change the number of operating units of the independent heat source unit 101, controls the variable flow rate of the primary flow rate that adjusts the flow rate of the primary cold water, controls the variable flow rate of the amount of cooling water, and controls the flow rate of the cooling tower fan. Controls the amount of change in air and changes the setting of the chilled water outlet temperature of the heat source.

The data collection server 200 is an example of a storage device, and is a computer having a database DB that stores sensor measurement values and operation data during operation of the heat source control system. For example, the data collection server 200 may be an EMS (Energy Management System) server that performs a function of managing the heat source control system 100 in conjunction with a real-time controller 105 or the like.

FIG. 2 is a diagram showing an example of a database DB of the data collection server 200. The data collection server 200 acquires sensor measurement values and operation data from the real-time controller 105 at predetermined interval periods, and sequentially records the acquired information in the database DB. As a result, the combination of the sensor measurement value and the operation data is recorded in the database DB in association with the date and time information. In this way, the database DB stores a combination of sensor measurement values and operation data for a certain period (for example, for the past one year or more). In the example of FIG. 2, the combination of the sensor measurement value and the operation data acquired at a predetermined date and time is shown line by line.

Here, the sensor measurement values and operation data stored in the database DB include, for example, the outside air wet-bulb temperature (WBoa), the secondary chilled water forward temperature (Tcs2), the secondary chilled water return temperature (Tcr2), and the secondary chilled water flow rate (Tcr2). Vc2), heat source primary side energy consumption (E1_HS1), secondary cold water pump energy consumption (EP_CP2), air conditioning load energy consumption (E1_AHU) are included. The energy consumption on the primary side of the heat source is the sum of the energy consumption of the equipment on the primary side (refrigerator 11, primary chilled water pump 12, fan of cooling tower 13, cooling water pump 14).

Further, the data collection server 200 deletes the above data from the database DB regarding the sensor measurement value and the operation data on the day when the complaint regarding air conditioning is received, or the above data is obtained when the calculation server 300 performs the calculation described later. It may be excluded from the extraction target. Similarly, when the sensor measurement value and the operation data include statistically abnormal values (for example, values outside the range of ± 2σ), the data collection server 200 deletes the data in the above case from the database DB, or deletes the data in the above case. Alternatively, the data in the above case may be excluded from the extraction target at the time of the calculation described later by the calculation server 300. By these processes, it is possible to exclude the data when the comfort of the air conditioner cannot be maintained at the time of the calculation described later by the calculation server 300, so that the accuracy of the calculation can be improved.

The arithmetic server 300 is an example of an arithmetic unit, and is a computer that executes arithmetic processing for obtaining a target value of the secondary chilled water forward temperature. The calculation server 300 receives information on the measured value of the secondary chilled water flow rate, the measured value of the secondary chilled water return temperature, the measured value of the secondary chilled water forward temperature, and the measured value of the outside air wet-bulb temperature from the real-time controller 105. Then, the calculation server 300 outputs the target value of the secondary chilled water forward temperature obtained by the calculation described later to the real-time controller 105. Further, the arithmetic server 300 communicates with the data collection server 200 to acquire the information stored in the database DB.

The calculation server 300 has a secondary load heat quantity calculation unit 301, a heat source primary side processing unit 302, a heat source secondary side processing unit 303, an air conditioning load processing unit 304, and a target value calculation unit 305. Each element included in the arithmetic server 300 may be constructed by hardware or software.

The secondary load heat amount calculation unit 301 calculates the secondary load heat amount using the measured value of the secondary chilled water flow rate, the measured value of the secondary chilled water return temperature, and the measured value of the secondary chilled water forward temperature.

The heat source primary side processing unit 302 calculates a plurality of sets of combinations of the heat source primary side energy consumption and the secondary chilled water forward temperature by using the measured value of the secondary chilled water flow rate and the measured value of the outside air wet-bulb temperature. Then, the heat source primary side processing unit 302 generates a first function F1 showing the correlation between the heat source primary side energy consumption and the secondary chilled water forward temperature.

The heat source secondary processing unit 303 is the energy consumption amount and the secondary chilled water forward temperature of the secondary chilled water pump corresponding to the conditions of the measured values of the secondary load heat amount and the outside air wet-bulb temperature calculated by the secondary load heat amount calculation unit 301. Multiple combinations with and are extracted from the database DB. Then, the heat source secondary processing unit 303 uses the energy consumption of the secondary chilled water pump and the secondary chilled water pump based on the distribution of the combination of the energy consumption of the secondary chilled water pump and the secondary chilled water forward temperature extracted from the database DB. A second function F2 showing the correlation with the cold water forward temperature is generated.

The air-conditioning load processing unit 304 combines the energy consumption of the air-conditioning load and the secondary cold water forward temperature corresponding to the conditions of the measured values of the secondary load heat amount and the outside air wet-bulb temperature calculated by the secondary load heat amount calculation unit 301. Extract multiple items from the database DB. Then, the air conditioning load processing unit 304 correlates the energy consumption of the air conditioning load with the secondary chilled water forward temperature based on the distribution of the combination of the air conditioning load energy consumption and the secondary chilled water forward temperature extracted from the database DB. Generate a third function F3 indicating.

The target value calculation unit 305 synthesizes the first function F1, the second function F2, and the third function F3 to generate an objective function F4 showing the correlation between the energy consumption of the entire system and the secondary cold water forward temperature. Generate. Then, the target value calculation unit 305 calculates the secondary chilled water forward temperature at which the energy consumption of the entire system is minimized by the objective function F4 as the target value of the secondary chilled water forward temperature.

Next, a control example of the heat source control system 100 according to the embodiment will be described.

In the description of the control example of the heat source control system 100, the control related to the real-time controller 105 will be described first, and then the calculation process in the calculation server 300 will be described.

(Explanation of control related to real-time controller)
FIG. 3 shows an example of a control flow relating to the real-time controller 105. In the example of FIG. 3, it is possible to obtain four control target values at the same time by optimizing each of the time of the preliminary simulation and the time of real-time control, and the amount of calculation during real-time control is significantly reduced. At the same time, it enables highly accurate calculations.

The processes of steps S101 to S105 shown in FIG. 3 are processes in a preliminary simulation executed by a computer different from the real-time controller 105.

Here, in the preliminary simulation of steps S101 to S105, the energy consumption of the three devices of the heat source machine 11, the cooling tower fan of the cooling tower 13, and the cooling water pump 14 is minimized for each individual heat source unit 101, and the optimum value of the power is obtained. Each of the optimization calculations is performed. In this optimization calculation, the constraint condition (independent variable) is the outside air wet bulb temperature WB, the refrigerating calorific value Qc_R [i] of the refrigerator_R [i], and the chilled water outlet temperature Tc_out_R [i] of the refrigerator_R [i]. , The control variable is calculated with the constraint conditions fixed, with the cooling water volume Vcd_CDP [i] of the cooling water pump CDP [i] and the fan air volume Vg_CT [i] of the cooling tower CT [i] as control variables (dependent variables). For various state values in the process of being performed, a control variable (Vcd_CDP [Vcd_CDP [Vcd_CDP [Vcd_CDP] is performed by temporarily fixing a part of the state value and changing the remaining part to perform iterative calculation, and then sequentially changing the temporarily fixed amount to perform iterative calculation. The optimum solution, which is a combination of i] and Vg_CT [i]), is calculated. Here, the symbol "i" is an argument for designating any single heat source unit (or an element thereof), and in the present embodiment, it takes an integer value within the range of 1 to n.

Then, in the pre-simulation, the constraint conditions are changed in various patterns in a practical range, and the above optimization calculation is performed in each pattern. Then, by summarizing the calculation results, three types of functions are generated: "function for finding the minimum energy consumption of the three devices", "optimal operation function for cooling water flow rate", and "optimum operation function for cooling tower air volume". To do.

Hereinafter, the contents of the processes of steps S101 to S105 of FIG. 3 will be described in detail.

In step S101, the computer uses the following equation (1) to determine the energy consumption of the heat source machine 11, the cooling tower fan of the cooling tower 13, and the cooling water pump 14 in the independent heat source unit 101 for each independent heat source unit 101. Perform optimization. This equation (1) is an equation generated for each single heat source unit, and is an equation of constraint conditions (WB, Qc_R [i], Tc_out_R [i]) and control variables (Vcd_CDP [i], Vg_CT [i]). The equations that output the energy consumption of the heat source machine, cooling tower, and cooling water pump with respect to the input are used as the form of the optimization problem, and the equations are solved.
E_RCDPCT [i] = F _{E_RCDPCT} [i] (WB, Qc_R [i], Tc_out_R [i], Vcd_CDP [i], Vg_CT [i]) …… (1)
Here, "E_RCDPCT [i]" is an evaluation value indicating the energy consumption of three devices, the heat source machine 11i, the cooling tower fan of the cooling tower 13i, and the cooling water pump 14i included in the single heat source unit 101i. "F _{E_RCDPCT} [i] ()" is a device characteristic that returns the energy consumption of three devices, the heat source machine 11i, the cooling tower fan of the cooling tower 13i, and the cooling water pump 14i, in response to the conditions assigned in parentheses. It is a function. Further, "Vcd_CDP [i]" is a variable indicating the cooling water flow rate of the cooling water pump 14i. The relationship between the amount of heat processed by the cooling water Qcd = the difference between the cooling tower inlet temperature and the cooling tower outlet temperature (cooling water ΔT) × the cooling water flow rate is self-evident. Therefore, the variable indicating the cooling water flow rate of the cooling water pump 14i may be replaced with the assumed value of the cooling water ΔT. "Vg_CT [i]" is a variable indicating the air volume of the cooling tower fan of the cooling tower 13i. Cooling water in the cooling tower The object to be controlled to approach the set value of the cooling tower outlet temperature is the air volume of the cooling tower fan, and the degree of approach to the cooling tower outlet temperature set value and the degree of approach to the cooling tower outlet temperature set value are It is self-evident that there is a correlation. Therefore, the variable indicating the air volume of the cooling tower fan may be replaced with the set value of the cooling tower outlet temperature.

That is, in the preliminary simulation, the computer in step S101 uses the values of WB, Qc_R [i] and Tc_out_R [i] as constraint conditions, and the evaluation value E_RCDPCT [i] takes the minimum value (optimum value). Performs an optimization operation that calculates the combination of Vcd_CDP [i] and Vg_CT [i]) as the optimum solution.

Specifically, the computer in step S101 performs an optimization operation for all patterns obtained by combining the three constraint conditions by the following method.

As an example, the WB in the constraint condition changes in 5 ° C increments in the range of 2 to 27 ° C and takes 6 values. Further, Qc_R [i] in the constraint condition changes in 10% increments in the range of 10 to 100% and takes 10 different values. Further, Tc_out_R [i] in the constraint condition changes in 0.5 ° C. increments in the range of 7 to 12 ° C. and takes 11 different values. At this time, the combination of the three restraint conditions is a pattern of 660 types (6 × 10 × 11).

Then, the computer selects one type of arbitrary combination of constraint conditions, and under the selected combination of constraint conditions, the evaluation value E_RCDPCT [i] according to the equation (1) takes the minimum value (optimum value) of the control variable. Calculate the combination (Vcd_CDP [i] and Vg_CT [i]) as the optimal solution. When calculating this evaluation value E_RCDPCT [i], the computer changes Vcd_CDP [i] in the range of 0 to 100% in 10% increments and Vg_CT [i] in the range of 0 to 100% in 10% increments. It shall be changed. By this optimization operation, one combination of control variables (Vcd_CDP [i] and Vg_CT [i]) that is an optimum solution is calculated for the combination of one selected constraint condition.

To further explain this optimization calculation, the computer gives an initial value (for example, 32 ° C) to the cooling tower cooling water inlet temperature Tcd_in_CT [i], and the initial value (Tcd_in_CT [i]) and the constraint condition (outside air wet bulb temperature). WB), control variables (cooling water flow rate Vcd_CDP [i] of the cooling water pump, air volume Vg_CT [i] of the cooling tower fan of the cooling tower) are given to the following equation (2) to obtain the cooling water cooling tower outlet temperature. ..
Tcd_out_CT [i] = F _{Tcd_out_CT} (WB, Tcd_in_CT [i], Vcd_CDP [i], Vg_CT [i]) …… (2)
The computer substitutes the cooling water cooling tower outlet temperature Tcd_out_CT [i] into the refrigerator inlet temperature Tcd_in_R [i].
Tcd_in_R [i] = Tcd_out_CT [i] …… (3)
The computer has the refrigerating heat amount Qc_R [i] of the heat source machine R [i], the cooling water inlet temperature Tcd_in_R [i] of the refrigerator, the cooling water flow rate Vcd_CDP [i] of the cooling water pump, and the cooling water outlet temperature Tcd_out_R [i] of the refrigerator. Is given to the following equation (4) to calculate the energy consumption of the refrigerator body E_R [i].
E_R [i] = F _{E_R} (Qc_R [i], Tcd_in_R [i], Vcd_CDP [i], Tcd_out_R [i]) …… (4)
The computer calculates the amount of heat exhausted from the refrigerator Qcd_R [i] by the following formula (5).
Qcd_R [i] = Qc_R [i] + E_R [i] …… (5)
The computer calculates the refrigerator cooling water outlet temperature by the following formula (6).
Tcd_out_R [i] = Qcd_R [i] / (cpw × w × Vcd_CDP [i]) + Tcd_in_R [i] …… (6)
The computer substitutes the refrigerator cooling water outlet temperature Tcd_out_R [i] into the calculated value Tcd_in_CT [i] _calc_ of the cooling tower cooling water inlet temperature.
Tcd_in_CT [i] _calc = Tcd_out_R [i] …… (7)
The computer determines the error between the assumed value and the calculated value of the cooling water cooling tower inlet temperature by the following equation (8).
| Tcd_in_CT [i] _calc- Tcd_in_CT [i] | <Err …… (8)
If the error is greater than the predetermined range (Err) (if the determination in equation (8) is false), the computer will start from the initial value (eg 32 ° C) of the cooling tower cooling water inlet temperature Tcd_in_CT [i] to the predetermined temperature (eg 32 ° C). 0.1 ° C) Set the lowered value to the assumed value, and return to the first equation (2). On the other hand, when the error falls within the predetermined range (when the judgment of the formula (8) is true), the computer calculates the energy consumption of the refrigerator body when the error falls within the predetermined range by the following formula (9). ) To calculate the total energy consumption of each device.
E_RCDPCT [i] = E_R [i] + E_CDP (= F _{E_CDP} (Vcd_CDP [i])) + E_CT (= F _{E_CT} (Vg_CT [i])) …… (9)
Note that F _{Tcd_out_CT} (), F _{E_R} (), F _{E_CDP} (), and F _{E_CT} () are device characteristic functions created from the device performance published by each manufacturer.

Here, when trying to calculate the combination of the control variables (Vcd_CDP [i] and Vg_CT [i]) in which the evaluation value E_RCDPCT [i] has the minimum value (optimum value) as the optimum solution, the computer tries to calculate the control variable (Vcd_CDP [i]]. i] and Vg_CT [i]) must be set as loop variables, and the convergence judgment of the cooling water cooling tower inlet temperature Tcd_in_CT [i] must be performed. Such calculations are very burdensome and difficult to calculate in real time. Therefore, by pre-simulating this part and making it a table function, the load during real-time calculation is reduced.

Next, the computer changes the combination of constraint conditions to perform the same optimization operation as described above for all 660 types of patterns. As a result, the computer acquires information on the correspondence between the combination of constraint conditions and the combination of control variables that is the optimum solution under that condition for all 660 types of patterns.

In step S102, the computer "minimum consumption of the heat source machine 11i, the cooling tower 13i, and the cooling water pump 14i" based on the calculation result of the optimum solution in the combination of WB, Qc_R [i] and Tc_out_R [i] in step S101. Generate an energy calculation function. This "calculation function of the minimum energy consumption of the heat source machine 11i, the cooling tower fan of the cooling tower 13i, and the cooling water pump 14i" is generated for each individual heat source unit.

For example, the computer determines the minimum consumption of the heat source machine 11i, the cooling tower 13i, and the cooling water pump 14i from the three variables WB, Qc_R [i], and Tc_out_R [i] based on the calculation result of the optimum solution in step S101. The function shown in Eq. (10) for obtaining energy is generated.
E_RCDPCT_min [i] = F _{E_RCDPCT_min} [i] (WB, Qc_R [i], Tc_out_R [i]) …… (10)
Here, "E_RCDPCT_min [i]" is a variable indicating the minimum energy consumption of the heat source machine 11i, the cooling tower fan of the cooling tower 13i, and the cooling water pump 14i, and " _{FE_RCDPCT_min} [i] ()" is a variable of the simulation. Based on the result, it is a function that returns the minimum energy consumption of the heat source machine 11i, the cooling tower fan of the cooling tower 13i, and the cooling water pump 14i for the variables assigned in parentheses.

As described in step S101, the optimization operation in the pre-simulation is performed for each pattern of the combination of constraint conditions, and the minimum energy consumption of the three devices corresponding to each pattern is also required. Utilizing this, the "calculation function of the minimum energy consumption of the heat source machine 11i, the cooling tower fan of the cooling tower 13i, and the cooling water pump 14i" is to input the patterns of the three constraint conditions and the minimum energy consumption in the patterns. Is generated in the form of a data table associated with the output value indicating. The data table of "the calculation function of the minimum energy consumption of the heat source machine 11i, the cooling tower fan of the cooling tower 13i, and the cooling water pump 14i" is stored in the storage unit (not shown) of the real-time controller 105.

In step S103, the computer generates an "optimal operating function of the cooling water pump 14i" based on the calculation result of the optimum solution in the combination of WB, Qc_R [i] and Tc_out_R [i] in step S101. This "optimal operating function of the cooling water pump 14i" is generated for each single heat source unit.

For example, the computer obtains the cooling water flow rate of the cooling water pump 14i from the three variables WB, Qc_R [i], and Tc_out_R [i] based on the calculation result of the optimum solution in step S101 (11). ) Is generated.
Vcd_CDP [i] = F _{Vcd_CDP} [i] (WB, Qc_R [i], Tc_out_R [i]) …… (11)
Here, "F _{Vcd_CDP} [i] ()" is a function that returns the cooling water flow rate of the cooling water pump 14i for the condition assigned in parentheses based on the calculation result of the optimum solution in step S101. is there.

As described in step S101, the optimization calculation in the pre-simulation is performed for each pattern of the combination of constraint conditions, and the cooling water flow rate of the optimum solution corresponding to each pattern is also obtained. Utilizing this, the "optimal operation function of the cooling water pump 14i" is in the form of a data table in which the input of the three constraint condition patterns and the output value indicating the cooling water flow rate in the pattern are associated with each other. Will be generated. The data table of the "optimal operation function of the cooling water pump 14i" is stored in the storage unit (not shown) of the real-time controller 105.

In step S104, the computer generates an "optimal operation function of the cooling tower 13i" based on the calculation result of the optimum solution in the combination of WB, Qc_R [i] and Tc_out_R [i] in step S101. This "optimal operating function of the cooling tower 13i" is generated for each single heat source unit.

For example, the computer obtains the air volume of the cooling tower fan of the cooling tower 13i from the three variables WB, Qc_R [i], and Tc_out_R [i] based on the calculation result of the optimum solution in step S101. Generate the function shown in 8).
Vg_CT [i] = F _{Vg_CT} [i] (WB, Qc_R [i], Tc_out_R [i]) …… (12)
Here, "F _{Vg_CT} [i] ()" is a function that returns the air volume of the cooling tower fan of the cooling tower 13i for the condition assigned in parentheses based on the calculation result of the optimum solution in step S101. Is.

As described in step S101, the optimization calculation in the pre-simulation is performed for each pattern of the combination of constraint conditions, and the air volume of the cooling tower of the optimum solution corresponding to each pattern is also obtained. Utilizing this, the "optimal operation function of the cooling tower 13i" is a data table format in which the input of the three constraint condition patterns and the output value indicating the air volume of the cooling tower fan in the pattern are associated with each other. Is generated by. The data table of the "optimal operation function of the cooling tower 13i" is stored in the storage unit (not shown) of the real-time controller 105.

In addition, each of "calculation function of minimum energy consumption of heat source machine 11i, cooling tower fan of cooling tower 13i and cooling water pump 14i", "optimal operation function of cooling water pump 14i", "optimal operation function of cooling tower 13i" The data table is simultaneously determined based on the result of the optimization operation of S101. Further, in each of the data tables generated in S102 to S104, the increments of the variables of WB, Qc_R [i] and Tc_out_R [i] are discrete, and the WB, Qc_R [i] and are limited on the data table. Output value information is retained only for the pattern of Tc_out_R [i]. Therefore, when the information of the minimum energy consumption corresponding to the place where the variable is not incremented on the data table is required at the time of real-time control described later, the real-time controller 105 obtains the position (WB,) using the output value of the data table. Output corresponding to the desired variable by performing trilinear interpolation (three-dimensional linear interpolation) that interpolates with a linear equation using 2 × 2 × 2 = 8 points around Tc_out_R [i], Qc_R [i]). The value will be calculated. On the other hand, the nearest neighbor interpolation is the same as the pre-table method, and it is a cubic expression using 4 × 4 × 4 = 64 points around the desired position (WB, Tc_out_R [i], Qc_R [i]). Interpolation Tricubic interpolation increases the calculation load. The vicinity of the minimum value of the energy consumption of the heat source as in this case is considered to be a concave curved surface that is smooth and has little change, and sufficient accuracy can be obtained even with three-dimensional linear interpolation such as trilinear interpolation, and the amount of calculation during interpolation is also reduced. ..

In step S105, the computer determines whether or not the functions of steps S102 to S104 have been generated for all the single heat source units 101. When the functions of steps S102 to S104 are generated for all the single heat source units 101 (YES), the computer ends the processing of the preliminary simulation. On the other hand, if the functions of steps S102 to S104 are not generated for any of the single heat source units 101 (NO), the process returns to step S101 and the computer repeats the above process. By the loop of steps S101 to S105, each function of steps S102 to S104 is generated for each of the independent heat source units 101 (1) to 101 (n) at the time of simulation.

Then, the processes after step S106 shown in FIG. 3 are the processes at the time of real-time control executed by the real-time controller 105 of the heat source control system 100 shown in FIG.

In the real-time control of the heat source control system 100, the real-time controller 105 uses the above-mentioned "calculation function of the minimum energy consumption of the heat source machine 11i, the cooling tower fan of the cooling tower 13i, and the cooling water pump 14i" to perform the entire system of the composite heat source. Form the energy consumption of the optimization problem. Then, the real-time controller 105 optimizes the combined heat source so that the energy consumption of the composite heat source is minimized by using WB, Vc2, and Tcr2 as constraints and Vc_R [1 to n] and Tc_out_R [1 to n] as control variables, and cold water. The calculation is performed with the flow rate and the chilled water outlet temperature as the optimum solution and set as the control target value. By using real-time measured values and operating state information instead of pre-estimated values for calculation input during real-time control, the real-time controller 105 controls the amount of refrigerating heat assuming that the inlet temperature difference is constant with the chilled water of the refrigerator. Rather than using variables, it is possible to perform highly accurate optimization using the temperature and flow rate as the amount of heat of refrigeration as control variables. Then, the computer in step S101 executes only six values of the outside air wet-bulb temperature WB in the range of 2 to 27 ° C. and changes in 5 ° C. increments among the restraint conditions. , Real-time outside air wet-bulb temperature measurement values are substituted instead of the six previously assumed values, so highly accurate optimization can be performed.

In other words, in the computer that performs the pre-simulation, the outside air wet-bulb temperature WB is executed in the range of 2 to 27 ° C, for example, only 6 values that change in 5 ° C increments to create a data table function. However, since the real-time outside air wet-bulb temperature measurement value is substituted for the calculation input during real-time control instead of the six values that are assumed in advance, highly accurate optimization can be performed.

Further, in the real-time control of the heat source control system 100, the real-time controller 105 uses the above-mentioned "optimal operation function of the cooling water pump 14i" and uses WB, Qc_R [i], Tc_out_R [i] as the input of the cooling water. The calculation is performed to obtain the control target value of the cooling water flow rate from the optimum operation function of the flow rate. Similarly, in the real-time control of the heat source control system 100, the real-time controller 105 uses the above-mentioned "optimal operation function of the cooling tower 13i" and uses WB, Qc_R [i], Tc_out_R [i] as the input of the cooling tower. The calculation is performed to obtain the control target value of the cooling tower air volume from the optimum operation function of the air volume.

Through these processes, the real-time controller 105 can simultaneously calculate four control target values (chilled water flow rate, chiller cold water outlet temperature, cooling water flow rate, cooling tower air volume) during real-time control. At the time of real-time control, an operation of calculating four control target values is executed in a cycle of, for example, about 5 to 20 minutes.

Hereinafter, the contents of the processes after step S106 in FIG. 3 will be described in detail.

In step S106, the real-time controller 105 of the heat source control system 100 optimizes the energy consumption of the composite heat source by the following equation (13).
Etotal = Σ {F _{E_RCDPCT_min} [i] (WB, Qc_R [i], Tc_out_R [i]) + F _{E_CP} [i] (Vc_R [i])}
= F _Etotal (WB, Vc2, Tcr2, Vc_R [1 ~ n], Tc_out_R [1 ~ n]) …… (13)
Here, "F _{E_CP} [i]" is the primary chilled water pump 12 obtained from the relationship obtained from the performance curve of the actual flow rate and power of the pump as hardware for the condition substituted in parentheses. It is a function that returns the energy consumption of. "F _Etotal ()" is a function that returns the energy consumption of the composite heat source for the condition assigned in parentheses. "Vc2" is a variable indicating the secondary chilled water flow rate, and "Tcr2" is a variable indicating the secondary chilled water return temperature.

In step S106, the real-time controller 105 substitutes the measured values of the sensor into the constraint conditions WB, Vc2 and Tcr2, and the control variables Vc_R [1 to n] and Tc_out_R [1 to Tc_out_R [1 to] in which the evaluation value Etotal is the optimum value. Find the combination of n] in real time.
Further, Qc_R [i] in the equation (13) is Cpw, ρw, Vc_R [i], (Tc_in_R [i] -Tc_out_R [i]) from the equation (14) described later. Here, the refrigerator chilled water inlet temperature Tc_in_R [i] is the flow-weighted average of the secondary chilled water forward temperature Tcs2 and the secondary chilled water return temperature Tcr2 when the bypass flow Vcbp passing through the bypass path 31 is positive (Vcbp> 0). The secondary chilled water forward temperature Tcs2 is the flow-weighted average of the chiller chilled water outlet temperature Tc_out_R [i], and when Vcbp <0, it is the secondary chilled water return temperature Tcr2, which is the highest in equation (13) anyway. The line can be transformed like the bottom line.

The formulas for obtaining the energy consumption of each single heat source unit 101i are the above formula (10), which is the formula for obtaining the minimum energy consumption of the heat source machine 11i, the cooling tower fan of the cooling tower 13i, and the cooling water pump 14i, and 1 It can be derived by summing the formulas for calculating the energy consumption of the next chilled water pump 12.

Then, the energy consumption in the composite heat source determines the combination of the single heat source units 101 (1) to 101 (n) to be operated from the composite heat sources, and the single heat source units 101 (1) to 101 (n) to be operated. By summing up the energy consumption of, it can be summarized as shown in the top line of equation (13). The energy consumption of this composite heat source can be expressed in the form of an optimization problem such as the bottom line of equation (13). The process of rearranging the equation (13) is omitted.

When the equation (9) is derived based on the above idea and the optimization calculation based on the equation (9) is performed so that the total value of the energy consumption of all the devices of the composite heat source becomes the minimum value, the real-time controller 105 Can obtain the chilled water flow rate and the chilled water outlet temperature corresponding to the heat source machines 11 (1) to 11 (n) as the optimum solution, respectively.

For example, the real-time controller 105 finds a combination of control variables Vc_R [1 to n] and Tc_out_R [1 to n] whose evaluation value Etotal is the minimum value (optimum value) when the constraint conditions are WB, Vc2 and Tcr2. .. In the optimization operation during real-time control, the constraint condition for inputting the expression is uniquely determined according to the situation during real-time control. That is, the real-time controller 105 substitutes the measured value of the sensor into the constraint conditions WB, Vc2 and Tcr2, and combines the control variables Vc_R [1 to n] and Tc_out_R [1 to n] in which the evaluation value Etotal is the optimum value. In real time. For the heat source machine 11i that is not operating due to inspection or failure during the above calculation, the optimization calculation may be performed with Vc_R [i] = 0. Since this operation can be performed, the optimum calculation can be performed in real time using the operating conditions of each refrigerator and each independent heat source in real time, and the optimum calculation assuming the number of refrigerators in operation and the operation order in advance becomes unnecessary, and the operation is currently in operation. Optimal operation with only the refrigerator is possible in a form that facilitates arithmetic processing.

By such an optimization calculation, the real-time controller 105 sets the chilled water flow rate corresponding to the heat source machines 11 (1) to 11 (n) as the control target value (Vc_R [1 to n]) of the primary chilled water pump 12 and sets the heat source machine. The chilled water outlet temperature corresponding to 11 (1) to 11 (n) is set as the control target value (Tc_out_R [1 to n]) of the heat source machines 11 (1) to (n).

In step S107, the real-time controller 105 uses the data table of the “optimal operation function of the cooling water pump 14i” generated in step S103 to control the cooling water flow rate of the cooling water pump 14 (Vcd_CDP [1 to n). ]) Is asked. At this time, the real-time controller 105 substitutes the measured value of the sensor into the WB, Qc_R [i], Tc_out_R [i] which are the function inputs, and obtains the control target value (Vcd_CDP [1 to n]) in real time. When the actual amount of "Vcd_CDP [i]" which is the calculation result is the cooling water flow rate, it is proportional to the cooling water pump inverter frequency, and when the actual amount of "Vcd_CDP [i]" is the assumed value of the cooling water ΔT. Is "Cooling water outlet temperature setting value of the refrigerator = Cooling water inlet temperature measurement value of the refrigerator (measurement is required to prevent malfunction of the refrigerator) + Assumed value of cooling water ΔT", and the cooling water outlet of the refrigerator The variable flow rate control of the cooling water pump is performed so that the measured temperature value becomes the set value of the cooling water outlet temperature. The former is the calculation logic itself, but it controls only the flow rate of the heat medium and does not directly control the temperature field. In this case, since the flow rate is controlled, the flow rate corresponding to the load can be managed. In addition, if the cooling water outlet temperature in the condenser of the refrigerator drops, the pressure difference with the evaporator may become too small, which may fill the gaps in the metal housing around the compressor to prevent leakage of compressed gas. The circulation of the lubricating oil is stagnant and causes seizure. However, by using the latter ΔT as a representative value, the function of preventing the above-mentioned seizure can also be given to the actual amount of the calculation result “Vcd_CDP [i]”.

Here, the value of Qc_R [i], which is the input of the function in step S107, is obtained from the following equation (14).
Qc_R [i] = Cpw ・ ρw ・ Vc_R [i] ・ (Tc_in_R [i] -Tc_out_R [i])… (14)
Here, both "Vc_R [i]" and "Tc_out_R [i]" in the equation (14) are the calculation results in step S106. Further, "Tc_in_R [i]" in the equation (14) is a measured value. “Cpw” is a physical constant indicating the specific heat of water, and “ρw” is a physical constant indicating the density of water.

In step S108, the real-time controller 105 uses the data table of the “optimal operating function of the cooling tower fan of the cooling tower 13i” generated in step S104 to control the air volume of the cooling tower 13 (Vg_CT [1 to n]). ]) Is asked. At this time, the real-time controller substitutes the measured value of the sensor into WB, Qc_R [i], Tc_out_R [i] which are the function inputs, and obtains the control target value (Vg_CT [1 to n]) in real time. When the actual amount of "Vg_CT [i]" which is the calculation result is the cooling tower air volume, it is proportional to the cooling tower air volume fan inverter frequency, and the actual volume of "Vg_CT [i]" is the cooling tower outlet temperature set value. In this case, the cooling tower fan air change amount control is performed so that the measured value of the cooling tower outlet temperature becomes the cooling tower outlet temperature set value. The cooling tower outlet set value is often the same as the cooling water inlet temperature set value for the refrigerator. In addition, if the cooling water inlet temperature in the condenser of the refrigerator drops, the pressure difference with the evaporator may become too small, and the circulation of the lubricating oil to prevent leakage of compressed gas may be delayed, causing seizure. , If the cooling water inlet temperature in the condenser of the refrigerator rises too much, the condenser may become abnormally high pressure. By controlling the measured value of the cooling tower outlet temperature to be the cooling tower outlet temperature set value, the function of preventing the above seizure and abnormal high pressure is also added to the actual amount of the calculation result "Vg_CT [i]". Can have.

In step S108, the calculation method of Qc_R [i] is the same as in step S107.

In this way, at the time of real-time control, the real-time controller 105 controls each element included in the composite heat source of the heat source control system 100 based on the calculated four control target values.

(Explanation of arithmetic processing on the arithmetic server)
FIG. 4 shows an example of arithmetic processing in the arithmetic server 300 in the heat source control system 100 of one embodiment. In the example of FIG. 4, a case where the calculation server 300 calculates the target value of the secondary chilled water forward temperature during the operation of the heat source control system 100 will be described. Note that FIG. 4 shows an example in which the processes of steps S202 and S203, the processes of steps S204 and S205, and the processes of steps S206 and S207 are executed in parallel, but these processes are executed in series. May be good.

In step S201, the secondary load heat amount calculation unit 301 calculates the secondary load heat amount.

The secondary load calorific value calculation unit 301 uses the real-time controller 105 to measure the secondary chilled water flow rate Vc2 [m ³ / sec], the secondary chilled water return temperature Tcr2 [deg], and the secondary chilled water forward temperature. Acquire the measured values of Tcs2 [deg] respectively. Then, the secondary load heat amount calculation unit 301 calculates the secondary load heat amount Qc2 [kw] by the following formula (15).
Qc2 ＝ Vc2 × Cw × (Tcr2-Tcs2) × ρw… (15)
In equation (15), Cw [kg / (kg'・ C)] is a physical constant indicating the specific heat of water, and ρw [kg / m ³ ] is a physical constant indicating the density of water.

In step S202, the heat source primary side processing unit 302 uses the measured value of the secondary chilled water flow rate Vc2 and the measured value of the outside air wet-bulb temperature WBoa [deg] to consume the heat source primary side energy consumption E1_HS1 [MJ / h]. Calculate multiple sets of combinations of and the set value of the secondary cold water forward temperature Tcs2.

First, the calculation server 300 acquires the measured value of the outside air wet-bulb temperature W Boa from the outside air temperature / humidity sensor 106 via the real-time controller 105. When the outside air temperature / humidity sensor 106 measures the outside air dry-bulb temperature DBoa [deg] and the outside air relative humidity RH [%], the real-time controller 105 or the calculation server 300 causes the outside air dry-bulb temperature DBoa [deg] and the outside air relative humidity RH [%]. The measured value of the outside air wet-bulb temperature WBoa may be calculated using each measured value of.

Next, the heat source primary side processing unit 302 tentatively determines a plurality of set values (Tcs2_SP [deg]) of the secondary cold water forward temperature Tcs2 as sample points for obtaining the heat source primary side energy consumption E1_HS1. For example, the heat source primary processing unit 302 sets four points of 7, 8, 9, and 10 [deg] as Tcs2_SP.

Further, the heat source primary side processing unit 302 adds the design value ΔT [deg] of the temperature difference between Tcs2 and Tcr2 to the set value Tcs2_SP of the secondary chilled water forward temperature, so that the secondary chilled water return temperature corresponding to Tcs2_SP Calculate Tcr2 (Tcs2_SP + ΔT) respectively. As described above, when Tcs2_SP is 7, 8, 9, and 10, the calculated Tcr2 is expressed as 7 + ΔT, 8 + ΔT, 9 + ΔT, and 10 + ΔT [deg], respectively. Further, the design value ΔT of the temperature difference is a fixed value (for example, 5 ° C.) determined at the time of system design, and is different from the temperature difference between Tcs2 and Tcr2 based on the actual measurement of the sensor.

Here, the reason for calculating the secondary chilled water return temperature Tcr2 by Tcs2_SP + ΔT is that the secondary chilled water return temperature Tcr2 corresponding to the tentatively determined secondary chilled water forward temperature set value Tcs2_SP is unknown, so Tcr2 is used using the design value. The calculation is simplified by calculating.

Then, the heat source primary side processing unit 302 uses the measured value of the secondary chilled water flow rate Vc2 and the measured value of the outside air wet-bulb temperature WBoa, and sets the secondary chilled water forward temperature according to the following equation (13)'. For each Tcs2_SP, calculate the heat source primary energy consumption E1_HS1. The following equation (13)'for obtaining the energy consumption E1_HS1 on the primary side is the same equation as the optimization of the energy consumption Etotal of the composite heat source in step S106 of the real-time controller 105 of the heat source control system 100 (Etotal and E1_HS1 are the same). Value). As described above, the heat source primary processing unit 302 of the arithmetic server 300 has the same processing as a part of the control flow of the real-time controller 105.
E1_HS1 = Σ {F _{E_RCDPCT_min [i]} (WB, Qc_R [i], Tc_out_R [i]) + F _{E_CP [i]} (Vc_R [i])}
= F _Etotal (WB, Vc2, Tcr2, Vc_R [1 ~ n], Tc_out_R [1 ~ n]) …… (13)'
Here, in the equation (13)', " _{FE_RCDPCT_min [i]} ()" is the cooling tower fan of the heat source machine 11i and the cooling tower 13i for the variables assigned in parentheses based on the simulation result. And a function that returns the minimum energy consumption of the cooling water pump 14i. "WB" is a variable indicating the outside air wet-bulb temperature. "Qc_R [i]" is a variable indicating the amount of freezing heat in the heat source machine 11i. "Tc_out_R [i]" is a variable indicating the chilled water outlet temperature of the heat source machine 11i. "F _{E_CP [i]} " is the energy consumption of the primary chilled water pump 12 obtained from the relationship obtained from the performance curve between the actual flow rate of the pump as hardware and the power with respect to the condition substituted in parentheses. Is a function that returns. "Vc_R [i]" is a variable indicating the chilled water flow rate corresponding to the heat source machine 11i (that is, the chilled water flow rate by the primary chilled water pump). "F _Etotal ()" is a function that returns the energy consumption of a composite heat source, which is a group of n single heat source units, for the condition assigned in parentheses. "Vc2" is a variable indicating the secondary chilled water flow rate, and "Tcr2" is a variable indicating the secondary chilled water return temperature. Each function included in the equation (13)'is generated by a preliminary simulation.

Further, in the above equation (13)', the reason for considering the outside air wet-bulb temperature is that the efficiency of the refrigerator performance improves as the cooling water temperature decreases, and the lower the outside air wet-bulb temperature, the lower the cooling temperature in the cooling tower. Because water can be generated, the efficiency of the refrigerator changes according to the outside air wet-bulb temperature.

Then, the heat source primary processing unit 302 in step S202 measures the secondary chilled water flow rate Vc2 and the outside air wet-bulb temperature WBoa for the restraint conditions WB and Vc2 with respect to the above equation (13)'. Substitute each value. Further, the heat source primary processing unit 302 substitutes Tcs2_SP + ΔT (that is, 7 + ΔT, 8 + ΔT, 9 + ΔT, 10 + ΔT) obtained by the above calculation for Tcr2 of the constraint condition with respect to the above equation (13)'. ..

Further, in the calculation in step S202, it is not premised that the chilled water flow rate of the primary chilled water pump 12i and the chilled water outlet temperature of the heat source machine 11i are optimized and controlled. In the calculation of the above equation (13)', the measured values are input to the outside air wet-bulb temperature WB and the secondary chilled water flow rate Vc2, respectively, and the design value ΔT is added to the tentatively determined secondary chilled water forward temperature set value Tcs2_SP2. The next cold water return temperature Tcr2 is input, and the variable Vc_R [i] and the variable Tc_out_R [i] are used as loop variables to obtain the minimum energy consumption E1_HS1 on the primary side.

In this way, the heat source primary side processing unit 302 corresponds to the heat source primary side energy consumption E1_HS1 corresponding to the set values Tcs2_SP of the secondary chilled water forward temperature at four points tentatively determined by the above equation (13)'. Calculate the four values of.

Explaining in detail the processing performed by the heat source primary side processing unit 302, the information generated in each individual heat source unit 101 (outside air wet bulb temperature WBoa, heat generation amount Qc_R [i] of heat source machine 11i, and heat source machine 11i Information indicating the correspondence between the chilled water outlet temperature Tc_out_R [i] and the minimum energy consumption of the heat source unit, cooling tower fan, and cooling water pump of the single heat source unit), the heat source unit, cooling tower fan, and cooling water. By summing the first formula for calculating the minimum energy consumption of the pump and the second formula for calculating the energy consumption of the primary chilled water pump based on the flow rate of chilled water to the heat source machine, the energy consumption of the single heat source unit E_RCDPCT [ Generate a third equation for finding i]. Then, using the measured values of the secondary chilled water flow rate Vc2 and the measured values of the outside air wet-bulb temperature WBoa, the outside air wet-bulb temperature WBoa and the secondary chilled water flow rate Vc2 are expressed in a plurality of third equations corresponding to each individual heat source unit. The measured value of the above and the secondary chilled water return temperature Tcr2 obtained by adding the design value ΔT to the tentatively determined secondary chilled water forward temperature Tcs2 are substituted to calculate the heat generation amount Qc_R [i] of the heat source machine. In addition, the outside air wet bulb temperature W Boa and the chilled water outlet temperature of the heat source machine Tc_out_R [i] stored in advance in the data table of the calculation function of the minimum energy consumption of the heat source machine 11i, the cooling tower fan of the cooling tower 13i, and the cooling water pump 14i. , From the three-dimensional grid of the heat generated by the heat source machine Qc_R [i], the substituted outside air wet bulb temperature WBoa, the chilled water outlet temperature of the heat source machine Tc_out_R [i], and the eight points near the heat generated by the heat source machine Qc_R [i] Energy consumption in each single heat source unit E_RCDPCT [i] by three-dimensional linear interpolation using the outside air wet bulb temperature W Boa, the chilled water outlet temperature of the heat source machine Tc_out_R [i], and the amount of heat generated by the heat source machine Qc_R [i]. The optimization calculation for finding the control target value of the chilled water flow rate Vc_R [i] and the control target value of the chilled water outlet temperature Tc_out_R [i] of the single heat source unit is executed so that the total value of is minimized. The combination of the heat source primary energy consumption E1_HS1 (total value of the energy consumption E_RCDPCT [i] in each single heat source unit) obtained in the process of executing this optimization calculation and the tentatively determined secondary cold water forward temperature Tcs2 is combined. A plurality of sets are calculated, and based on the calculation result, a first function showing the correlation between the energy consumption on the primary side of the heat source and the forward temperature of the secondary chilled water is generated.

FIG. 5A is a graph showing an example of the correspondence between the heat source primary energy consumption E1_HS1 and the secondary chilled water forward temperature Tcs2. The vertical axis of FIG. 5A is energy consumption, and the horizontal axis of FIG. 5A is temperature.

In FIG. 5A, the values of E1_HS1 at the four points where Tcs2_SP is 7, 8, 9, and 10 are plotted. When lowering the secondary cold water forward temperature Tcs2, more energy is consumed on the primary side. Therefore, as shown in FIG. 5A, the smaller the Tcs2_SP, the larger the value of E1_HS1.

In step S203, the heat source primary side processing unit 302 generates a first function F1 (equation (16)) showing the correlation between the heat source primary side energy consumption and the secondary cold water forward temperature.
E1_HS1 = F1 (Tcs2) …… (16)
For example, the heat source primary side processing unit 302 executes a known function fitting process using the data of each point in the graph of FIG. 5A, and determines the heat source primary side energy consumption and the secondary chilled water forward temperature. The first function F1, which is an approximate function of, is obtained. The approximate function may be any function as long as it is a downward-sloping function, but in consideration of the simplicity of calculation, the first function F1 in step S203 is a quadratic function (y = ax ² + bx + c). .. Note that FIG. 5B is a diagram in which the first function F1 is plotted in FIG. 5A. The first function F1 is a downward-sloping function.

In step S204, the heat source secondary processing unit 303 uses the secondary load heat quantity Qc2 and the outside air wet-bulb temperature WBoa to generate the energy consumption EP_CP2 of the secondary chilled water pump and the secondary chilled water from the database DB of the data collection server 200. Obtain statistical information in combination with temperature Tcs2.

The heat source secondary processing unit 303 uses the secondary load heat quantity Qc2 calculated in step S201 and the outside air wet-bulb temperature WBoa as search keys to combine sensor measurement values and operation data stored in the database DB (row in FIG. 2). ), Multiple combinations corresponding to the conditions of the secondary load heat quantity Qc2 and the outside air wet-bulb temperature WB are extracted. Here, "the conditions of the secondary load heat amount Qc2 and the outside air wet-bulb temperature WB correspond" is within a predetermined allowable range even if the value of the database DB does not match the value of the search key. In this case, it means that the heat source secondary processing unit 303 handles the value of the database DB as the extraction target. For example, when the value of the secondary load heat quantity Qc2 of the database DB is within a predetermined range (for example, within ± 10% of the design maximum load heat quantity) based on the secondary load heat quantity Qc2 calculated in step S201. The heat source secondary processing unit 303 handles the data in the above database DB as an extraction target. Similarly, when the value of the outside air wet-bulb temperature WB of the database DB is within a predetermined range (for example, within the range of ± 5 ° C.) based on the measured value of the outside air wet-bulb temperature WBoa, the heat source secondary processing unit 303 treats the data of the above database DB as an extraction target.

Then, the heat source secondary processing unit 303 acquires the information of the energy consumption EP_CP2 of the secondary chilled water pump and the secondary chilled water forward temperature Tcs2 in association with each of the extracted combinations. That is, when there are m sets of sensor measurement values and operation data extracted from the database DB, statistical information of the energy consumption EP_CP2 of the secondary chilled water pump for m sets and the secondary chilled water forward temperature Tcs2 is acquired. become.

In general, the amount of heat of the air conditioning load is greatly affected by the temperature and humidity of the outside air. The air-conditioning load in the indoor space (interior zone) surrounded by an air-conditioned space without an outer wall is not easily affected by the temperature and humidity conditions of the outside air, but the air-conditioning load in the indoor space (perimeter zone) near the window and on the outer wall side is It is easily affected by the temperature and humidity of the outside air. In addition, the external controller is directly affected by the temperature and humidity conditions of the outside air. Therefore, it can be expected that the calculation accuracy will be improved by adding the outside air wet-bulb temperature to the variable.

FIG. 6A is a graph showing an example of the correspondence between the energy consumption EP_CP2 of the secondary chilled water pump and the secondary chilled water forward temperature Tcs2. The vertical axis of FIG. 6A is energy consumption, and the horizontal axis of FIG. 6A is temperature. When the statistical information of the energy consumption EP_CP2 of the secondary chilled water pump for m sets and the secondary chilled water forward temperature Tcs2 is acquired, m points are plotted in FIG. 6A.

If the secondary chilled water forward temperature Tcs2 is lowered, the amount of secondary chilled water sent to cover the amount of heat on the secondary side is reduced, so that the energy consumption of the secondary chilled water pump is reduced. Therefore, as shown in FIG. 6A, as a qualitative tendency of statistical information, the smaller Tcs2_SP, the smaller the value of EP_CP2 tends to be distributed.

In step S205, the heat source secondary processing unit 303 generates a second function F2 (Equation (17)) showing the correlation between the energy consumption of the secondary chilled water pump and the secondary chilled water forward temperature.
E1_CP2 = F2 (Tcs2) …… (17)
For example, the heat source secondary processing unit 303 executes a known function fitting process using the data of each point in the graph of FIG. 6A, and the energy consumption of the secondary chilled water pump and the secondary chilled water forward temperature. The second function F2, which is an approximate function of, is obtained. The approximate function may be any function as long as it rises to the right, but in consideration of the simplicity of calculation, the second function F2 in step S205 is a quadratic function (y = dx ² + ex + f). .. Note that FIG. 6B is a diagram in which the second function F2 is plotted on FIG. 6A. The second function F2 is an upward-sloping function.

In step S206, the air conditioning load processing unit 304 uses the secondary load heat quantity Qc2 and the outside air wet-bulb temperature WBoa to obtain the energy consumption amount E1_AHU of the air conditioning load and the secondary cold water forward temperature Tcs2 from the database DB of the data collection server 200. Get the combination statistics.

The air conditioning load processing unit 304 uses the secondary load heat quantity Qc2 calculated in step S201 and the outside air wet-bulb temperature WBoa as search keys to combine the sensor measurement values and the operation data stored in the database DB (row in FIG. 2). From these, multiple combinations corresponding to the conditions of the secondary load heat quantity Qc2 and the outside air wet-bulb temperature WB are extracted. Here, "the conditions of the secondary load heat quantity Qc2 and the outside air wet-bulb temperature WB correspond" is within a predetermined allowable range even if the value of the database DB does not match the value of the search key. In this case, it means that the air conditioning load processing unit 304 handles the value of the database DB as the extraction target. For example, when the value of the secondary load heat quantity Qc2 of the database DB is within a predetermined range (for example, within ± 10% of the design maximum load heat quantity) based on the secondary load heat quantity Qc2 calculated in step S201. , The air conditioning load processing unit 304 handles the data of the above database DB as an extraction target. Similarly, when the value of the outside air wet-bulb temperature WB of the database DB is within a predetermined range (for example, within the range of ± 5 ° C.) based on the measured value of the outside air wet-bulb temperature WBoa, the heat source secondary processing unit 303 handles the data of the above database DB as an extraction target.

Then, the air conditioning load processing unit 304 acquires the information of the energy consumption amount E1_AHU of the air conditioning load and the secondary chilled water forward temperature Tcs2 in association with each of the extracted combinations. That is, when there are m sets of sensor measurement values and operation data extracted from the database DB, statistical information of the energy consumption E1_AHU of the air conditioning load for m sets and the secondary cold water forward temperature Tcs2 will be acquired. ..

As described in step S204, it can be expected that the calculation accuracy will be improved by adding the outside air wet-bulb temperature to the variable.

FIG. 7A is a graph showing an example of the correspondence between the energy consumption E1_AHU of the air conditioning load and the secondary chilled water forward temperature Tcs2. The vertical axis of FIG. 7 (a) is energy consumption, and the horizontal axis of FIG. 7 (a) is temperature. When the statistical information of the energy consumption E1_AHU of the air conditioning load for m sets and the secondary cold water forward temperature Tcs2 is acquired, m points are plotted in FIG. 7A.

When the secondary cold water forward temperature Tcs2 is lowered, the efficiency of the air conditioning operation is improved, so that the energy consumption of the air conditioning load is reduced. Therefore, as shown in FIG. 7A, as a qualitative tendency of the statistical information, the smaller Tcs2_SP, the smaller the value of E1_AHU tends to be distributed.

In step S207, the air conditioning load processing unit 304 generates a third function F3 (equation (18)) showing the correlation between the energy consumption of the air conditioning load and the secondary chilled water forward temperature.
E1_AHU ＝ F3 (Tcs2) …… (18)
For example, the air conditioning load processing unit 304 executes a known function fitting process using the data of each point in the graph of FIG. 7A, and approximates the energy consumption of the air conditioning load and the secondary chilled water forward temperature. The third function F3 is obtained. The approximate function may be any function as long as it rises to the right, but in consideration of the simplicity of calculation, the third function F3 in step S207 is a quadratic function (y = gx ² + hx + j). .. Note that FIG. 7B is a diagram in which the third function F3 is plotted on FIG. 7A. The third function F3 is an upward-sloping function.

In step S208, the target value calculation unit 305 synthesizes the first function F1, the second function F2, and the third function F3 to show the correlation between the energy consumption of the entire system and the secondary cold water forward temperature. Generate the objective function F4. The first function F1, the second function F2, and the third function F3 are all quadratic functions showing the correlation between the energy consumption and the secondary cold water forward temperature. Therefore, the target value calculation unit 305 can calculate the objective function F4 by adding the coefficients of the functions F1, F2, and F3 for each degree, as shown in the following equation (19).
y = (a + d + g) x ² + (b + e + h) x + (c + f + j) …… (19)
FIG. 8 is a graph showing the functions F1 to F4. The vertical axis of FIG. 8 is energy consumption, and the horizontal axis of FIG. 8 is temperature.

As described above, the first function F1 is a downward-sloping function, and the second function F2 and the third function F3 are both upward-sloping functions. Therefore, it can be seen that the objective function F4 obtained by synthesizing these is a function having a downward convexity and has a minimum value for energy consumption. Then, the target value calculation unit 305 calculates the secondary chilled water forward temperature at which the energy consumption of the entire system is minimized by the objective function F4 as the target value of the secondary chilled water forward temperature.

The target value calculation unit 305 compares the calculated target value of the secondary chilled water forward temperature with, for example, the upper limit value of the secondary chilled water forward temperature set in advance for each month, and calculates the secondary chilled water forward temperature. When the target value of is exceeded the upper limit of the secondary chilled water forward temperature, the upper limit of the secondary chilled water forward temperature may be set as the target value of the secondary chilled water forward temperature.

Then, the target value of the secondary chilled water forward temperature calculated by the calculation server 300 is output to the real-time controller 105. After that, the real-time controller 105 controls the refrigerator 11, the primary chilled water pump 12, and the secondary chilled water pumps 85a and 85b based on the target value of the secondary chilled water forward temperature. As a result, the optimized control of the heat source control system 100 can be executed. This is the end of the description of the control example shown in FIG.

Hereinafter, the action and effect in one embodiment will be described.

The calculation server 300 in one embodiment has a first function F1 showing the correlation between the energy consumption on the primary side of the heat source and the secondary chilled water forward temperature, and a correlation between the energy consumption of the secondary chilled water pump and the secondary chilled water forward temperature. The second function F2 showing the above and the third function F3 showing the correlation between the energy consumption of the air conditioning load and the secondary chilled water forward temperature are combined to obtain the energy consumption of the entire system and the secondary chilled water forward temperature. The objective function F4 showing the correlation is generated. Then, the calculation server 300 calculates the secondary chilled water forward temperature at which the energy consumption of the entire system is minimized by the objective function F4 as the target value of the secondary chilled water forward temperature (S208).

Here, in one embodiment, the first function F1 regarding the energy consumption on the primary side of the heat source can be easily calculated based on the performance of the equipment on the primary side, and thus is obtained by physical calculation (S202, S203). On the other hand, the second function F2 regarding the energy consumption of the secondary chilled water pump and the third function F3 regarding the energy consumption of the air conditioning load need to consider various factors on the secondary side, and therefore during system operation. Using the sensor measurement values and operation data of the above, statistical processing is performed from the distribution of each parameter extracted according to the secondary load heat quantity and the outside air wet bulb temperature (S204, S205, S206, S207).

Therefore, according to the heat source control system 100 of one embodiment, by performing control based on the target value of the secondary chilled water forward temperature calculated by the calculation server 300, the entire air conditioning heat source equipment can be controlled without relying on the experience and intuition of the operator. It is possible to set the secondary chilled water supply temperature that minimizes energy consumption, and it is possible to realize control that achieves both comfort and energy saving. Further, according to the heat source control system 100 of one embodiment, it is possible to automatically and in real time change the setting according to the situation even when the operator is not operating.

Further, in one embodiment, the steps for obtaining the first function F1, the second function F2, and the third function F3 are separated from each other, and each function is obtained by a different method according to the properties thereof. That is, in one embodiment, the function F1 is obtained by arithmetic processing for the energy consumption on the primary side of the heat source, and the functions F2 and F3 are obtained by statistical processing for the energy consumption of the secondary cold water pump and the energy consumption of the air conditioning load, respectively. And combine these functions to generate the objective function F4, which shows the correlation between the energy consumption of the entire system and the secondary cold water forward temperature. Therefore, in one embodiment, as compared with the case where the energy consumption of the primary side device and the secondary side device are collectively statistically analyzed as in the prior art, the arithmetic processing for obtaining the optimum solution of the secondary cold water forward temperature is performed. Can be done very easily.

<Configuration example of primary pump type heat source control system>
FIG. 9 shows a configuration example of the primary pump type heat source control system 100A. In the primary pump system, the cold water pump that conveys the cold water of the heat source system is only one stage of the cold water primary pump. In the case of the primary pump system, the configuration is simple, and the surplus is bypassed between the headers by controlling the chilled water flow rate on the air conditioning load side, so the system is advantageous in that the chilled water inflow temperature to the air conditioning load is basically stable. However, in the case of the primary pump system, a large flow rate may flow through the bypass between headers, and the chilled water primary pump is responsible for the entire head of the chilled water piping system, so that optimum control as energy saving is difficult.

In the description of FIG. 9, the same elements as those of the heat source control system shown in FIG. 1 are designated by a common reference numeral and duplicated description will be omitted.

The primary pump system is a piping system in which cold water is circulated to the air conditioner (AHU) only by the primary chilled water pump. The heat source control system 100A shown in FIG. 9 does not have the second forward header 83, the secondary chilled water pumps 85a, 85b and the pipeline 87 shown in FIG. 1 on the secondary side of the heat source, and the forward header 102 does not have the secondary forward chilled water. The pipe 39 is connected.

As described above, in the heat source control system 100A shown in FIG. 9, the secondary side of the heat source is configured by the forward header 102, the return header 103, the air conditioner (AHU) 104, and the piping connecting them.

Further, the data collection server 200 and the calculation server 300A are connected to the real-time controller 105 of the heat source control system 100A shown in FIG. 9 via the network 400, respectively.

The database DB of the data collection server 200 of FIG. 9 is the same as the database DB shown in FIG. 1 except that there is no operation data of the energy consumption of the secondary chilled water pump. Further, the calculation server 300A shown in FIG. 9 has no heat source secondary processing unit 303 and has a target value calculation unit 305A instead of the target value calculation unit 305. Is similar to.

FIG. 10 shows an example of arithmetic processing in the arithmetic server 300A in the heat source control system 100A of another embodiment. In the example of FIG. 10, for the same processing as in FIG. 4, common reference numerals are given and duplicate description is omitted.

In the example of FIG. 10, the arithmetic server 300A does not perform the processes of steps S204 and S205, but executes the processes of steps S202 and S203 and the processes of steps S206 and S207. Then, the arithmetic server 300A executes the process of step S208A instead of step S208.

In step S208A, the target value calculation unit 305A synthesizes the first function F1 and the third function F3 to generate an objective function F4 showing the correlation between the energy consumption of the entire system and the secondary cold water forward temperature. .. Then, the target value calculation unit 305A calculates the secondary chilled water forward temperature at which the energy consumption of the entire system is minimized by the objective function F4 as the target value of the secondary chilled water forward temperature.

As described above, in the heat source control system 100A of the other embodiment, the same operation and effect as in the case of one embodiment can be obtained.

<Supplementary matters of the embodiment>
(1) The configuration of the heat source control system is not necessarily limited to the configuration of the above embodiment. For example, the secondary forward thermometer (43) for measuring the secondary cold water forward temperature may be arranged in the second forward header 83, and the secondary return thermometer (51) for measuring the secondary cold water return temperature may be arranged. , May be placed in the return header 103. Further, the arithmetic servers 300 and 300A may acquire the measured values directly from each sensor without going through the real-time controller 105.

(2) In the above embodiment, the arithmetic processing of the arithmetic servers 300 and 300A for calculating the target value of the secondary chilled water forward temperature using the measured value of the sensor has been described. However, the arithmetic servers 300 and 300A may calculate the target value of the secondary chilled water forward temperature by using the predicted value of each parameter as an input value instead of the current value (measured value). By calculating the target value of the secondary chilled water forward temperature using the predicted value in this way, it is possible to predict the operating status of the heat source control systems 100 and 100A.

(3) In the above embodiment, the target value calculation units 305 and 305A calculate the secondary chilled water forward temperature at which the energy consumption of the entire system is minimized as the target value of the secondary chilled water forward temperature by the objective function F4. explained. However, the target value calculation units 305 and 305A do not set the secondary chilled water forward temperature at which the energy consumption of the entire system is minimized as the target value of the secondary chilled water forward temperature, and the energy consumption of the entire system is minimized. An approximate value of the secondary cold water forward temperature may be used as a target value of the secondary cold water forward temperature. For example, the target value calculation units 305 and 305A set the temperature close to the secondary chilled water forward temperature at which the energy consumption of the entire system is minimized according to the step size when the secondary chilled water forward temperature is changed in the heat source control system. It may be used as a target value for the next cold water forward temperature.

(4) In the embodiment of the heat source control system of the primary / secondary pump system shown in FIGS. 1 to 8, the target value calculation unit 305 performs the first function F1, the second function F2, and the third function F3. An example of synthesizing and generating the objective function F4 has been described. However, the target value calculation unit 305 may generate the objective function F4 by excluding any of these functions. For example, the target value calculation unit 305 may combine the first function F1 and the second function F2 to generate the objective function F4. In this case, in the calculation server 300, the processing (S206, S207) of the air conditioning load processing unit 304 becomes unnecessary. Further, the target value calculation unit 305 may generate the objective function F4 by synthesizing the first function F1 and the third function F3, as in the case of the primary pump system. In this case, in the arithmetic server 300, the processing (S204, S205) of the heat source secondary processing unit 303 becomes unnecessary.

The above detailed description will clarify the features and advantages of the embodiments. It is intended that the claims extend to the features and advantages of the embodiments as described above without departing from their spirit and scope of rights. Also, anyone with ordinary knowledge in the art should be able to easily come up with any improvements or changes. Therefore, there is no intention to limit the scope of the embodiments having invention to those described above, and it is possible to rely on suitable improvements and equivalents included in the scope disclosed in the embodiments.

11 ... Refrigerator (heat source machine R), 12 ... Primary chilled water pump, 13 ... Cooling tower, 14 ... Cooling water pump, 43, 51 ... Temperature sensor, 53 ... Flow meter, 83 ... Second forward header, 85a, 85b ... Secondary chilled water pump, 100, 100A ... Heat source control system, 101 ... Independent heat source unit, 102 ... Outward header, 103 ... Return header, 104 ... Air conditioner (AHU), 105 ... Real-time controller, 106 ... Outside temperature and humidity sensor , 200 ... Data collection server, 300, 300A ... Calculation server, 301 ... Secondary load heat amount calculation unit, 302 ... Heat source primary side processing unit, 303 ... Heat source secondary side processing unit, 304 ... Air conditioning load processing unit, 305 ... Target value calculation unit, 400 ... Network

Claims (8)

With a refrigerator
A first header connected to the chilled water outlet side of the chiller by a chilled water primary outbound pipe,
A return header connected to the chilled water inlet side of the chiller by a chilled water primary return pipe via a primary chilled water pump.
A bypass pipe connecting the first forward header and the return header,
A second forward header connected to the first forward header by a forward header pipe via a secondary cold water pump, and
An air conditioning load connected between the second forward header and the return header via a cold water secondary forward pipe and a cold water secondary return pipe.
A secondary thermometer, which is arranged in the second forward header or the cold water secondary forward pipe and measures the secondary cold water forward temperature,
A secondary return thermometer that is placed in the return header or the cold water secondary return pipe and measures the secondary cold water return temperature.
A secondary flow meter arranged in the chilled water secondary return pipe and measuring the secondary chilled water flow rate,
An outside air temperature / humidity sensor that measures the outside air wet-bulb temperature,
An arithmetic unit for obtaining the target value of the secondary cold water forward temperature, and
A control device for controlling the refrigerator, the primary chilled water pump, and the secondary chilled water pump based on the target value of the secondary chilled water forward temperature.
With
The arithmetic unit
A secondary load heat quantity calculation unit that calculates a secondary load heat quantity using the measured value of the secondary chilled water flow rate, the measured value of the secondary chilled water return temperature, and the measured value of the secondary chilled water forward temperature.
Using the measured value of the secondary chilled water flow rate and the measured value of the outside air wet-bulb temperature, a plurality of combinations of the heat source primary side energy consumption amount, which is the energy consumption amount of the primary side equipment, and the secondary chilled water forward temperature are used. A heat source primary side processing unit that calculates a set and generates a first function showing the correlation between the heat source primary side energy consumption and the secondary cold water forward temperature based on the calculation result.
Based on the distribution of the combination of the energy consumption of the secondary chilled water pump and the secondary chilled water forward temperature during system operation, which was extracted based on the measured values of the secondary load heat amount and the outside air wet-bulb temperature. A heat source secondary treatment unit that generates a second function that indicates the correlation between the energy consumption of the secondary chilled water pump and the secondary chilled water forward temperature.
The air conditioning load is extracted based on the measured values of the secondary load heat quantity and the outside air wet-bulb temperature, and is based on the distribution of the combination of the energy consumption of the air conditioning load and the secondary cold water forward temperature during system operation. An air-conditioning load processing unit that generates a third function showing the correlation between the energy consumption of the secondary chilled water and the secondary cold water temperature.
The first function , the second function, and the third function are combined to generate an objective function showing the correlation between the energy consumption of the entire system and the secondary cold water forward temperature, and the objective function is used. With a target value calculation unit that calculates the secondary chilled water forward temperature that minimizes the energy consumption of the entire system and determines the target value of the secondary chilled water forward temperature based on the calculated secondary chilled water forward temperature. ,
A heat source control system characterized by having. With a refrigerator
A first header connected to the chilled water outlet side of the chiller by a chilled water primary outbound pipe,
A return header connected to the chilled water inlet side of the chiller by a chilled water primary return pipe via a primary chilled water pump.
A bypass pipe connecting the first forward header and the return header,
A second forward header connected to the first forward header by a forward header pipe via a secondary cold water pump, and
An air conditioning load connected between the second forward header and the return header via a cold water secondary forward pipe and a cold water secondary return pipe.
A secondary thermometer, which is arranged in the second forward header or the cold water secondary forward pipe and measures the secondary cold water forward temperature,
A secondary return thermometer that is placed in the return header or the cold water secondary return pipe and measures the secondary cold water return temperature.
A secondary flow meter arranged in the chilled water secondary return pipe and measuring the secondary chilled water flow rate,
An outside air temperature / humidity sensor that measures the outside air wet-bulb temperature,
An arithmetic unit for obtaining the target value of the secondary cold water forward temperature, and
A control device for controlling the refrigerator, the primary chilled water pump, and the secondary chilled water pump based on the target value of the secondary chilled water forward temperature.
With
The arithmetic unit
A secondary load heat quantity calculation unit that calculates a secondary load heat quantity using the measured value of the secondary chilled water flow rate, the measured value of the secondary chilled water return temperature, and the measured value of the secondary chilled water forward temperature.
Using the measured value of the secondary chilled water flow rate and the measured value of the outside air wet-bulb temperature, a plurality of combinations of the heat source primary side energy consumption amount, which is the energy consumption amount of the primary side equipment, and the secondary chilled water forward temperature are used. A heat source primary side processing unit that calculates a set and generates a first function showing the correlation between the heat source primary side energy consumption and the secondary cold water forward temperature based on the calculation result.
Based on the distribution of the combination of the energy consumption of the secondary chilled water pump and the secondary chilled water forward temperature during system operation, which was extracted based on the measured values of the secondary load heat amount and the outside air wet-bulb temperature. A heat source secondary treatment unit that generates a second function that indicates the correlation between the energy consumption of the secondary chilled water pump and the secondary chilled water forward temperature.
The first function and the second function are combined to generate an objective function showing the correlation between the energy consumption of the entire system and the secondary cold water temperature, and the objective function consumes the energy of the entire system. A target value calculation unit that calculates the secondary chilled water forward temperature that minimizes the amount and determines a target value of the secondary chilled water forward temperature based on the calculated secondary chilled water forward temperature.
Have,
A storage device that stores a plurality of combinations of the secondary load heat quantity, the outside air wet-bulb temperature, the energy consumption of the secondary chilled water pump, and the secondary chilled water forward temperature during system operation is further provided.
The heat source secondary processing unit includes the energy consumption of the secondary chilled water pump and the secondary, which correspond to the conditions of the secondary load heat amount calculated by the secondary load heat amount calculation unit and the measured values of the outside air wet-bulb temperature. A heat source control system characterized in that a plurality of combinations with the cold water forward temperature are extracted from the storage device. In the heat source control system according to claim 1 ,
A storage device that stores a plurality of combinations of the secondary load heat amount, the outside air wet-bulb temperature, the energy consumption amount of the air conditioning load, and the secondary chilled water forward temperature during system operation is further provided.
The air-conditioning load processing unit includes the energy consumption of the air-conditioning load and the secondary cold water forward temperature corresponding to the conditions of the secondary load heat amount calculated by the secondary load heat amount calculation unit and the measured values of the outside air wet-bulb temperature. A heat source control system, characterized in that a plurality of combinations of the above are extracted from the storage device. The refrigerator is connected to the chilled water outlet side of the refrigerator by a chilled water primary return pipe, and is connected to the chilled water inlet side of the refrigerator via a chilled water primary return pipe via a primary chilled water pump. A return header, a bypass pipe connecting the first forward header and the return header, and a second forward header connected to the first forward header by a forward header pipe via a secondary chilled water pump. An air conditioning load connected between the second forward header and the return header via a cold water secondary forward pipe and a cold water secondary return pipe, and the second forward header or the cold water secondary forward pipe are arranged. A secondary return thermometer that measures the secondary cold water return temperature, a secondary return thermometer that is placed in the return header or the cold water secondary return pipe and measures the secondary cold water return temperature, and the cold water secondary return pipe. A secondary flow meter that measures the secondary chilled water flow rate, an outside temperature / humidity sensor that measures the outside air / wet bulb temperature, and a control device that controls the refrigerator, the primary chilled water pump, and the secondary chilled water pump. It is a control method of a heat source control system equipped with
A step of calculating the secondary load heat amount using the measured value of the secondary chilled water flow rate, the measured value of the secondary chilled water return temperature, and the measured value of the secondary chilled water forward temperature.
Using the measured value of the secondary chilled water flow rate and the measured value of the outside air wet-bulb temperature, a plurality of combinations of the heat source primary side energy consumption amount, which is the energy consumption amount of the equipment on the primary side, and the secondary chilled water forward temperature are used. A step of calculating a set and generating a first function showing a correlation between the energy consumption on the primary side of the heat source and the forward temperature of the secondary chilled water based on the calculation result.
Based on the distribution of the combination of the energy consumption of the secondary chilled water pump and the secondary chilled water forward temperature during system operation, which was extracted based on the measured values of the secondary load heat quantity and the outside air wet-bulb temperature. A step of generating a second function showing the correlation between the energy consumption of the secondary chilled water pump and the secondary chilled water forward temperature, and
The air conditioning load is extracted based on the measured values of the secondary load heat quantity and the outside air wet-bulb temperature, and is based on the distribution of the combination of the energy consumption of the air conditioning load during system operation and the secondary cold water forward temperature. And the step of generating a third function showing the correlation between the energy consumption of the secondary cold water and the secondary cold water temperature.
The first function , the second function, and the third function are combined to generate an objective function showing the correlation between the energy consumption of the entire system and the secondary cold water forward temperature, and the objective function is used. A step of calculating the secondary chilled water forward temperature at which the energy consumption of the entire system is minimized, and determining a target value of the secondary chilled water forward temperature based on the calculated secondary chilled water forward temperature.
A step of outputting the target value of the secondary cold water forward temperature to the control device, and
A control method of a heat source control system, characterized in that it has. With a refrigerator
An outgoing header connected to the cold water outlet side of the refrigerator by a cold water primary outgoing pipe,
A return header connected to the chilled water inlet side of the chiller by a chilled water primary return pipe via a primary chilled water pump.
A bypass pipe connecting the forward header and the return header,
An air conditioning load connected between the forward header and the return header via a cold water secondary forward pipe and a cold water secondary return pipe.
A secondary thermometer that is placed in the forward header or the cold water secondary forward pipe and measures the secondary cold water forward temperature.
A secondary return thermometer that is placed in the return header or the cold water secondary return pipe and measures the secondary cold water return temperature.
A secondary flow meter arranged in the chilled water secondary return pipe and measuring the secondary chilled water flow rate,
An outside air temperature / humidity sensor that measures the outside air wet-bulb temperature,
An arithmetic unit for obtaining the target value of the secondary cold water forward temperature, and
A control device that controls the refrigerator and the primary chilled water pump based on the target value of the secondary chilled water forward temperature, and
With
The arithmetic unit
A secondary load heat quantity calculation unit that calculates a secondary load heat quantity using the measured value of the secondary chilled water flow rate, the measured value of the secondary chilled water return temperature, and the measured value of the secondary chilled water forward temperature.
Using the measured value of the secondary chilled water flow rate and the measured value of the outside air wet-bulb temperature, a plurality of combinations of the heat source primary side energy consumption amount, which is the energy consumption amount of the primary side equipment, and the secondary chilled water forward temperature are used. A heat source primary side processing unit that calculates a set and generates a first function showing the correlation between the heat source primary side energy consumption and the secondary cold water forward temperature based on the calculation result.
The air conditioning load is extracted based on the measured values of the secondary load heat quantity and the outside air wet-bulb temperature, and is based on the distribution of the combination of the energy consumption of the air conditioning load and the secondary cold water forward temperature during system operation. An air-conditioning load processing unit that generates a third function showing the correlation between the energy consumption of the secondary chilled water and the secondary cold water temperature.
The first function and the third function are combined to generate an objective function showing the correlation between the energy consumption of the entire system and the secondary cold water temperature, and the objective function consumes the energy of the entire system. A target value calculation unit that calculates the secondary chilled water forward temperature that minimizes the amount and determines a target value of the secondary chilled water forward temperature based on the calculated secondary chilled water forward temperature.
A heat source control system characterized by having. In the heat source control system according to claim 5 ,
A storage device that stores a plurality of combinations of the secondary load heat amount, the outside air wet-bulb temperature, the energy consumption amount of the air conditioning load, and the secondary chilled water forward temperature during system operation is further provided.
The air-conditioning load processing unit includes the energy consumption of the air-conditioning load and the secondary chilled water forward temperature corresponding to the conditions of the secondary load heat amount calculated by the secondary load heat amount calculation unit and the measured values of the outside air wet-bulb temperature. A heat source control system, characterized in that a plurality of combinations of the above are extracted from the storage device. The chiller is connected to the chilled water outlet side of the chiller by a chilled water primary return pipe, and is connected to the chilled water inlet side of the chiller by a chilled water primary return pipe via a primary chilled water pump. A return header, a bypass pipe connecting the forward header and the return header, and an air conditioning load connected between the forward header and the return header via a cold water secondary forward pipe and a cold water secondary return pipe. , The secondary forward thermometer which is arranged in the forward header or the cold water secondary forward pipe to measure the secondary cold water forward temperature, and the secondary cold water return temperature which is arranged in the return header or the cold water secondary return pipe. A secondary return thermometer to measure, a secondary flowmeter arranged in the cold water secondary return pipe to measure the secondary chilled water flow rate, an outside temperature / humidity sensor to measure the outside air wet bulb temperature, and the secondary cold water outflow. A control method for a heat source control system including a control device for controlling the refrigerator and the primary chilled water pump based on a target value of temperature.
A step of calculating the secondary load heat amount using the measured value of the secondary chilled water flow rate, the measured value of the secondary chilled water return temperature, and the measured value of the secondary chilled water forward temperature.
Using the measured value of the secondary chilled water flow rate and the measured value of the outside air wet-bulb temperature, a plurality of combinations of the heat source primary side energy consumption amount, which is the energy consumption amount of the equipment on the primary side, and the secondary chilled water forward temperature are used. A step of calculating a set and generating a first function showing a correlation between the energy consumption on the primary side of the heat source and the forward temperature of the secondary chilled water based on the calculation result.
The air conditioning load is extracted based on the measured values of the secondary load heat quantity and the outside air wet-bulb temperature, and is based on the distribution of the combination of the energy consumption of the air conditioning load during system operation and the secondary cold water forward temperature. And the step of generating a third function showing the correlation between the energy consumption of the secondary cold water and the secondary cold water temperature.
The first function and the third function are combined to generate an objective function showing the correlation between the energy consumption of the entire system and the secondary cold water temperature, and the objective function consumes the energy of the entire system. A step of calculating the secondary chilled water forward temperature at which the amount is minimized and determining a target value of the secondary chilled water forward temperature based on the calculated secondary chilled water forward temperature.
A step of outputting the target value of the secondary cold water forward temperature to the control device, and
A control method of a heat source control system, characterized in that it has. It is connected to the chilled water inlet side of the refrigerator by a chilled water primary return pipe via a refrigerator, an outgoing header connected to the chilled water outlet side of the chiller by a chilled water primary outgoing pipe, and a primary chilled water pump. A return header, a bypass pipe connecting the forward header and the return header, and an air conditioning load connected between the forward header and the return header via a cold water secondary forward pipe and a cold water secondary return pipe. , The secondary forward thermometer which is arranged in the forward header or the cold water secondary forward pipe to measure the secondary cold water forward temperature, and the secondary cold water return temperature which is arranged in the return header or the cold water secondary return pipe. A secondary return thermometer to measure, a secondary flowmeter arranged in the cold water secondary return pipe to measure the secondary chilled water flow rate, an outside temperature / humidity sensor to measure the outside air wet bulb temperature, and the secondary cold water outflow. A calculation device that calculates a target value of the secondary chilled water forward temperature of a heat source control system including a control device that controls the refrigerating machine and the primary chilled water pump based on the target value of the temperature.
A secondary load heat quantity calculation unit that calculates a secondary load heat quantity using the input value of the secondary chilled water flow rate, the input value of the secondary chilled water return temperature, and the input value of the secondary chilled water forward temperature.
Using the input value of the secondary chilled water flow rate and the input value of the outside air wet-bulb temperature, a plurality of combinations of the heat source primary side energy consumption amount, which is the energy consumption amount of the primary side equipment, and the secondary chilled water forward temperature are used. A heat source primary side processing unit that calculates a set and generates a first function showing the correlation between the heat source primary side energy consumption and the secondary cold water forward temperature based on the calculation result.
The air conditioning load is extracted based on the input values of the secondary load heat quantity and the outside air wet-bulb temperature, and is based on the distribution of the combination of the energy consumption of the air conditioning load and the secondary cold water forward temperature during system operation. An air-conditioning load processing unit that generates a third function showing the correlation between the energy consumption of the secondary chilled water and the secondary cold water temperature.
The first function and the third function are combined to generate an objective function showing the correlation between the energy consumption of the entire system and the secondary cold water temperature, and the objective function consumes the energy of the entire system. A target value calculation unit that calculates the secondary chilled water forward temperature that minimizes the amount and determines a target value of the secondary chilled water forward temperature based on the calculated secondary chilled water forward temperature.
An arithmetic unit characterized by having.

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