JP2017101862A - Heat source control system and control method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a heat source control system capable of optimal control calculating a high accuracy control target value while restricting the amount of computation in advance simulation and real time control and the data amount of the data table compared with the past.SOLUTION: A control device of a heat source control system, creates: a first equation for obtaining the minimal energy consumption using first information indicating the correspondence between an ambient air wet bulb temperature, the creation calorie of a heat source machine, a cold water outlet temperature, and the minimal energy consumption of the heat source machine/a cooling tower fan/a cooling water pump; a second equation for obtaining the energy consumption of a primary cold water pump based on the cold water flow rate; and a third equation for obtaining the energy consumption in each single heat source unit by summing up the second equation and the first equation, in which the optimization calculation of four control target values in total of a cold water flow rate in a plurality of single heat source units, a cold water outlet temperature, a cooling water flow rate, and an air capacity of the cooling tower fan, is performed in real time during operation, in order to minimize the total energy consumption in each single heat source unit.SELECTED DRAWING: Figure 4

Description

  The present invention relates to a heat source control system for an air conditioning facility including a plurality of heat sources and a control method therefor. In particular, the present invention relates to a heat source control system that optimizes the operation of the heat source so that the energy consumption of the entire heat source system is minimized according to the amount of heat of the air conditioning load and the outside air wet bulb temperature, and a control method thereof.

  Air-water heat that exchanges heat with conditioned air, such as air conditioning units installed in target buildings, such as health air conditioning that maintains comfort for people such as living rooms and factory air conditioning that improves and maintains the production efficiency of things in factories, etc. When the total number of air conditioning loads equipped with exchangers is large, in a heat source control system for air conditioning equipment, a large refrigerator can be used to adjust the amount of refrigeration in response to seasonal and building heat load fluctuations. It is often difficult, and even if it can be adjusted with one unit, the partial load characteristics often deteriorate. For the purpose of improving these situations, subdivide the refrigerator into a part of the air conditioning load. A plurality of heat sources as a unit including a refrigerator (heat source machine R), a chilled water pump (primary pump), a cooling tower, and a cooling water pump are provided for each chiller so that it can be stopped accordingly. Operation such as load flow rate or load heat quantity It is conventional to perform increase or decrease the number control of the heat source number running according to the conditions.

  In addition, for the purpose of energy saving, in the control of the number of heat sources in the heat source control system, when each of the independent variables changes using the heat load and the outside air state value as independent variables (in other words, search keys based on real-time information) Is obtained by simulation in advance using the optimum load distribution for minimizing energy and the optimum control amount of each device as a dependent variable under predetermined constraints, and a data table indicating the optimum control amount of each device is generated in advance. It is also proposed to select an independent variable close to the value based on real-time measurement information or command information, obtain a dependent variable from a data table, and perform optimal control of the heat source (see, for example, Patent Document 1). ).

  By the way, in addition to the start / stop control of the heat source unit R itself as the control of the increase / decrease of the number of heat sources in the heat source control system, the control of the amount of refrigeration by the control of the compressor and the cooling circulated between the condenser and the cooling tower of the refrigerator Heat source system that further saves energy as system control items such as cooling water temperature change by variable flow rate of cooling water pump that transports water and air flow control of cooling tower fan that can control the degree of heat exchange between outside air and cooling water The idea of building up has been penetrating recently. Therefore, although a local control device for each individual component device is installed, the entire system can be operated by combining various variable amount control of the devices that constitute the heat source with respect to successively changing outside air and air conditioning load. Whether it is good or not, optimal control of the heat source is becoming more difficult.

Japanese Patent No. 5489046

  In the optimal control of the heat source, the control point of the refrigerator as a hardware is to install a temperature sensor as the outlet temperature of the frozen chilled water and control the chiller outlet chilled water temperature to be constant, so the outlet temperature is stable, Since the inlet temperature is not stable because it is returned to the air-water heat exchanger according to the air-conditioning load situation where the load amount changes greatly regardless of the heat source side, it is not stable. The temperature difference of fluctuates sequentially. Therefore, when calculating the control target value of the chilled water flow rate from the generated heat amount of each refrigerator by a prior simulation, since the heat amount = the inlet / outlet temperature difference of the refrigerator × the flow rate, both the changing heat amount and the changing inlet / outlet temperature difference are calculated in advance. It is very difficult to calculate the control target value (cold water flow rate). As a measure to simplify the independent variables and calculation conditions as a preliminary simulation, for example, if the temperature difference at the inlet / outlet of the refrigerator is assumed to be 5 ° C and is calculated with a fixed value, the calculation will be simple but the inlet temperature will not be It is stable and the inlet / outlet temperature difference becomes unstable, and there is a limit to improving the accuracy of optimal control of the heat source. On the other hand, if a large number of temperature difference patterns are set as the calculation conditions and independent variables of the data table applied to the optimal control of the heat source, the amount of calculations and the amount of data in the data table in advance simulation and real-time control are enormous. It is not practical.

  In addition, in the optimal control of the heat source, when the simulation is performed by assuming the number of operating refrigerators and the operation sequence in advance, the calculation amount in the simulation and the data amount of the data table can be suppressed. When creating a data table as temperature, the number of operating units and the operating sequence of the refrigerators are determined regardless of the total heat quantity on the air conditioning load side, and the energy consumption does not necessarily depend on where in the partial load characteristics curve of each refrigerator. There are cases where it cannot be said to be the minimum, and there is a limit in improving the accuracy of the optimal control of the heat source. Therefore, if the number of refrigerators to be operated and the order of operation are not determined in advance and are determined from independent variables, a data table for the number of combination patterns of the operation order and the number of units is required, and enormous pre-calculation and selection calculations during real-time control are required. As a result, the calculation hardware is expensive and the calculation time is long, which is not practical. In addition, for example, it becomes difficult to cope with the operation when the number of operating units and the operating sequence are changed from the pre-estimation at the time of equipment failure or inspection.

  The object of the present invention is to use real-time measurement values and operating state information instead of pre-estimated values while suppressing the amount of calculation and data amount of the data table in the prior simulation and real-time control compared with the prior art. It is another object of the present invention to provide a heat source control system and a control method for the heat source control system that enable optimum control for calculating a control target value with high accuracy by obtaining the minimum value of energy consumption of the cold heat source system.

An example of the heat source control system according to the present invention is as follows:
An air conditioning load located on the secondary side formed by an air conditioner group or a water / air heat exchanger group that exchanges heat with air; and
A forward header for sending cold water toward the air conditioning load;
A return header for receiving cold water sent from the air conditioning load;
A plurality of single heat source units each connected to the forward header via a cold water primary forward pipe and to the return header via a cold water primary return pipe;
A control unit that includes a storage unit and controls the plurality of single heat source units;
With
Each of the single heat source units
A primary chilled water pump which is connected to the return header via a chilled water primary return pipe, gives a flow rate to the chilled water in the pipe and sends it out, and also controls the flow rate of the chilled water, and the primary chilled water pump of the chilled water primary return pipe The cold water sent from the primary chilled water pump connected to the downstream side of the chilled water, the heat source machine connected to the forward header via the chilled water primary outgoing pipe downstream of itself, and the result of the cold water refrigeration of the heat source machine Cooling water circulating to transfer exhaust heat between the cooling tower and the heat source unit, a cooling tower having a cooling tower fan for transferring the outside air, which cools the generated exhaust heat by heat exchange with the outside air A cooling water pump for controlling the flow rate,
The storage unit stores first information, second information, and third information, respectively.

  The first information is information generated in each of the single heat source units, and is the outside wet bulb temperature, the amount of generated heat of the heat source unit, the cold water outlet temperature of the heat source unit, and the one of the single heat source units. The correspondence relationship with the minimum energy consumption of a heat source machine, the cooling tower fan, and the cooling water pump is shown.

  The second information is information generated in each of the individual heat source units, and includes an outside air wet bulb temperature, a generated heat amount of the heat source unit, a cold water outlet temperature of the heat source unit, and a cooling water flow rate by the cooling water pump. The correspondence relationship with the control target value is shown.

  The third information is information generated in each of the single heat source units, and controls the outside air wet bulb temperature, the generated heat amount of the heat source unit, the cold water outlet temperature of the heat source unit, and the air volume of the cooling tower fan. The correspondence with the target value is shown.

  And the said control apparatus performs the following processes.

  The control device uses the first information to determine the primary expression based on a first expression for obtaining a minimum energy consumption of the heat source unit, the cooling tower fan, and the cooling water pump, and a cold water flow rate to the heat source unit. By summing up the second equation for determining the energy consumption of the cold water pump, a third equation for determining the energy consumption of the single heat source unit is generated.

  The control device uses the plurality of third formulas corresponding to each of the single heat source units to calculate the measured values of the outdoor air wet bulb temperature, the generated heat amount of the heat source unit, and the cold water outlet temperature of the heat source unit, which are sequentially acquired during operation. Substitute every predetermined sampling time, and obtain the control target value of the chilled water flow rate and the control target value of the chilled water outlet temperature of the single heat source unit so that the total value of the energy consumption in each of the single heat source units is minimized. Perform optimization calculations in real time during operation.

  The control device uses the second information to calculate the single heat source unit based on the value of the outdoor wet bulb temperature acquired at a predetermined sampling time during operation, the amount of heat generated by the heat source unit, and the cold water outlet temperature of the heat source unit. The control target value of the coolant flow rate of the coolant pump is determined.

  The control device uses the third information based on the value of the outdoor wet bulb temperature acquired at a predetermined sampling time during operation, the amount of generated heat of the heat source unit, and the cold water outlet temperature of the heat source unit, and the single heat source unit. The control target value of the air volume of the cooling tower fan is obtained.

Other examples of the invention include
An air conditioning load located on the secondary side formed by an air conditioner group or a water / air heat exchanger group that exchanges heat with air; and
A forward header for sending cold water toward the air conditioning load;
A return header for receiving cold water sent from the air conditioning load;
A plurality of single heat source units each connected to the forward header via a cold water primary forward pipe and to the return header via a cold water primary return pipe;
A control device for controlling a plurality of the individual heat source units;
With
Each of the single heat source units
A primary chilled water pump which is connected to the return header via a chilled water primary return pipe, gives a flow rate to the chilled water in the pipe and sends it out, and also controls the flow rate of the chilled water, and the primary chilled water pump of the chilled water primary return pipe The cold water sent from the primary chilled water pump connected to the downstream side of the chilled water, the heat source machine connected to the forward header via the chilled water primary outgoing pipe downstream of itself, and the result of the cold water refrigeration of the heat source machine Cooling water circulating to transfer exhaust heat between the cooling tower and the heat source unit, a cooling tower having a cooling tower fan for transferring the outside air, which cools the generated exhaust heat by heat exchange with the outside air A control method of a heat source control system including a cooling water pump for controlling a flow rate.

In this control method,
According to the simulation before operation, for each of the single heat source units, the outside air wet bulb temperature, the generated heat amount of the heat source unit and the cold water outlet temperature of the heat source unit, the heat source unit of the single heat source unit, the cooling tower fan And generating first information indicating a correspondence relationship with the minimum energy consumption of the cooling water pump,
Correspondence between the outdoor heat wet bulb temperature, the heat generation amount of the heat source unit, the cold water outlet temperature of the heat source unit, and the control target value of the cooling water flow rate by the cooling water pump, for each of the individual heat source units by the simulation before operation Generating second information indicating the relationship;
Based on the simulation before operation, for each of the individual heat source units, the correspondence relationship between the outside wet bulb temperature, the heat generation amount of the heat source unit, the cold water outlet temperature of the heat source unit, and the control target value of the air amount of the cooling tower fan is determined. Generate third information to indicate
When the control device performs real-time control during operation,
Consumption of the primary chilled water pump based on the first equation for obtaining the minimum energy consumption of the heat source unit, the cooling tower fan and the cooling water pump using the first information and the flow rate of chilled water to the heat source unit By summing the second equation for obtaining energy, a third equation for obtaining energy consumption of the single heat source unit is generated,
A plurality of third equations corresponding to each of the individual heat source units are used to calculate the measured values of the outdoor wet bulb temperature, the generated heat amount of the heat source unit, and the chilled water outlet temperature of the heat source unit that are continuously acquired during operation at a predetermined sampling time. For each of the individual heat source units, and an optimization calculation for obtaining the control target value of the cold water flow rate and the control target value of the cold water outlet temperature of the single heat source unit so that the total value of the energy consumption in each of the single heat source units is minimized. Run,
The cooling water of the single heat source unit using the second information based on the value of the outdoor wet bulb temperature acquired at a predetermined sampling time during operation, the amount of heat generated by the heat source unit, and the cold water outlet temperature of the heat source unit Find the control target value of the coolant flow rate of the pump,
The cooling tower of the single heat source unit using the third information based on the value of the outdoor wet bulb temperature acquired at a predetermined sampling time during operation, the amount of generated heat of the heat source unit, and the value of the cold water outlet temperature of the heat source unit The control target value of the air volume is obtained.

  According to the heat source control system and the control method of the present invention, compared with the conventional method, the calculation amount and the data amount of the data table at the time of the prior simulation and the real time control are suppressed, and the real time measurement is performed instead of the prior assumed value. Optimal control for calculating a control target value with high accuracy is possible by obtaining the minimum value of the energy consumption of the cooling heat source system using the information on the value and the operating state.

  In addition, as an independent variable (in other words, a search key based on real-time information), a value that represents the heat quantity and temperature field of the cooling water that minimizes the energy is set under a predetermined constraint when each independent variable changes. Data generated in advance to indicate the operating status in which the total energy consumption of each device is minimized by obtaining the value and power value of each device of the refrigerator, cooling water pump, and cooling tower fan as a dependent variable by the dependent function through simulation. The optimum control amount of the single heat source unit is obtained from the table, but the independent heat source unit has three independent variables: the outside air wet bulb temperature, the freezer generated heat amount, and the freezer cold water outlet temperature. Since the chiller cold water outlet temperature can be changed from the viewpoint of energy saving for each, further optimum operation control can be performed. In addition, since it is possible to change the chiller cold water outlet temperature for each individual heat source, it is possible to perform optimum control with a minimum amount of header-by-header bypass even in the primary pump system where optimum control is difficult.

  In addition, optimal calculations can be made in real time using the operating conditions of each real-time refrigerator and each individual heat source, eliminating the need for optimal calculations assuming the number of operating units and the operating sequence in advance. It is possible to perform the optimal operation in a form that can be easily processed.

It is a figure which shows the structural example of the heat source control system of a primary secondary pump system. It is a figure which shows the structural example of the heat source control system of a primary pump system. It is a figure which shows the example of optimization calculation control of the heat source control system in a comparative example. It is a figure which shows the example of optimization calculation control of the heat-source control system in embodiment of this invention.

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

  The present invention can be applied to a heat source control system including a composite heat source composed of a plurality of single heat source units. Here, the single heat source unit is a group of components related to one refrigerator, and is composed of four devices including a refrigerator (heat source machine R), a primary cold water pump, a cooling tower, and a cooling water pump. including. Further, the composite heat source refers to the entire system composed of n individual heat source units (n is a positive integer of 2 or more).

  The heat source control system may be either a primary pump system or a primary secondary pump system. The configuration of the primary secondary pump type heat source control system and the configuration of the primary pump type heat source control system will be described below. In the following description, the case of cold water will be described.

(Configuration example of heat source control system of primary and secondary pump type)
FIG. 1 shows a configuration example of a heat source control system 100 of a primary secondary pump system. The primary / secondary pump system is designed to optimize the bypass flow rate between headers so that the chiller flow rate on the refrigerator side and the air conditioning load side do not have to be the same, with the forward header and return header as the boundary. (Heat source machine R) 11, the cold water primary return pipe 15 and the cold water primary return pipe 16 that connect the forward header 102 and the return header 103 are each handled as a lift, and the cold water is circulated to the primary side. In order to use the primary chilled water pump 12 to circulate the chilled water to the air conditioning load side such as the air conditioner 104, the forward header, the cold water secondary forward pipe 39, the cold water secondary return pipe 41, and the heat of the air conditioner 104 are used. This is a piping system that uses a cold water secondary pump (85a, 85b) that has a head that is the sum of the pressure losses of the exchanger parts.

  A 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 an outside air temperature / humidity sensor 106 for measuring the outside air wet bulb temperature. 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 there are a plurality of air conditioners (AHU) 104 as air conditioning loads.

  In the present embodiment, the n single heat source units 101 may differ in the performance of each element (especially if there is a difference depending on the type of the refrigerator or a difference due to the heat transfer area of the cooling tower) The basic configuration is the same or similar. Here, the configuration of one single heat source unit 101 (n) will be described, and redundant description regarding each single heat source unit 101 will be omitted. The single heat source unit 101 (n) includes the refrigerator (heat source machine R) 11, the primary cold water pump 12, the cooling tower 13, and the cooling water pump 14 as described above.

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

  The refrigerator (heat source machine R) 11 is connected to the forward header 102 via a cold water primary return pipe 15 and is connected to the return header 103 via a cold water primary return pipe 16. Here, the cold water primary forward pipe 15 is a primary side of the cold water, and is a pipe that supplies the cold water cooled (refrigerated) by the heat source machine R to the forward header 102. The cold water primary return pipe 16 is the primary side of the cold water, and the cold water whose temperature has been increased by the air conditioner 104 and returned to the header 103 is returned to the header 103, and the combined return cold water is returned from the return header 103 to the heat source machine R. It is a pipe that feeds water.

  Information of the cold water outlet temperature SP (Set Point: set value) is input from the real-time controller 105 to the refrigerator (heat source device R) 11. Information indicating the heat source operation state is output from the refrigerator (heat source machine R) 11 to the real time controller 105.

  The cold water primary outgoing pipe 15 is provided with a temperature sensor 17 for measuring the cold water outlet temperature of the refrigerator (heat source machine R) 11. The temperature PV (Process Value: measurement 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 refrigerator (heat source machine R) 11. And a temperature sensor 19 are 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 includes an inverter (INV) as a power source for the pump motor. The rotational speed of the primary chilled water pump 12 is varied by frequency control of the power source by the inverter (INV) according to an instruction from the real-time controller 105.

  A cooling water pump 14 is connected to the refrigerator (heat source machine R) 11 by an annular cooling water pipe 21 connected to an inlet / outlet of a heat exchanger such as a condenser for exchanging heat of exhaust heat so that the cooling water can be taken in and out. Via the cooling tower 13. Due to the conveying force of the cooling water pump 14 through the cooling water pipe 21, the cooling water whose temperature has been increased by the exhaust heat of the heat source apparatus R is sent from the heat source apparatus R to the cooling tower 13. Further, the cooling power is lowered by cooling the outside air and the cooling water by the cooling tower fan provided in the cooling tower 13 from the cooling tower 13 by the conveying force of the cooling water pump 14 through the cooling water pipe 21. Water is sent to the heat source machine R.

  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 by the cooling tower fan or indirect contact with the outside air. The cooling water pump 14 sends the cooling water cooled by the cooling tower 13 to the refrigerator (heat source device R) 11. The cooling tower fan and the cooling water pump 14 of the cooling tower 13 are each provided with an inverter (INV) as a power source of each motor. And the rotation speed of the cooling tower fan of the cooling tower 13 and the cooling water pump 14 is changed by the frequency control of the power source by the inverter (INV) according to the instruction of the real time controller 105.

  The forward header 102 and the return header 103 are connected via a bypass 31.

  As described above, in the heat source control system 100 shown in FIG. 1, the n individual heat source units 101, the forward header 102, the return header 103, the chilled water primary side forward pipe 15 and the chilled water primary side return that connect them. The piping 16 and the bypass 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 disposed on the downstream side of the forward header 102 with the secondary chilled water pumps 85a and 85b disposed in parallel on the secondary side of the heat source. The forward header 102 and the second forward header 83 are connected to each other through secondary cold water pumps 85a and 85b through short chilled water secondary piping. Further, between the forward header 102 and the second forward header 83, a bypass conduit 87 that is used for controlling the pressure of the cold water sent to the air conditioning load (not shown) is connected.

  Between the second forward header 83 and the return header 103, a cold water secondary forward pipe 39 that connects the second forward header 83 and the air conditioner (AHU) 104, an air conditioner (AHU) 104, and the return header. A cold water secondary return pipe 41 is provided for connecting to the H. 103. Here, the cold water secondary forward pipe 39 is a secondary side of the cold water, and is a pipe that feeds the cold water frozen by the heat source machine R from the second forward header 83 to the air conditioner 104. The chilled water secondary piping 39 is provided with a temperature sensor 43 that measures the temperature of water supply to an air conditioning load in which a plurality of air conditioners 104 are combined. The cold water secondary return pipe 41 is a secondary side of the cold water, and is a pipe for supplying cold water whose temperature has been increased by heat exchange in the air conditioner 104 to the return header 103 from the air conditioner 104. The chilled water secondary return pipe 41 is provided with a temperature sensor 51 that measures the temperature of the chilled water that is returned to the return header 103 after heat exchange is performed with an air conditioning load including a plurality of air conditioners 104, 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.

  Thus, in the heat source control system 100 shown in FIG. 1, the secondary header of the heat source is provided by the forward header 102, the return header 103, the second forward header 83, the air conditioner (AHU) 104, and the piping connecting them. The side is configured.

  The real-time controller 105 is an example of a control device. For example, a main device constituting hardware is a PLC (Programmable Logic Controller). 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 individual heat source units 101, the variable flow control of the primary flow rate that adjusts the flow rate of the primary chilled water, the variable flow rate control of the cooling water amount, the cooling tower fan Performs variable air volume control, heat source cold water outlet temperature setting change control, etc. In addition, the real-time controller 105 has a storage unit 107 that stores programs and various data tables. The storage unit 107 is, for example, a nonvolatile semiconductor memory or a hard disk.

(Configuration example of primary pump type heat source control system)
FIG. 2 shows a configuration example of a heat source control system 100A of the primary pump type. In the primary pump system, the chilled water pump that conveys the chilled water of the heat source system is only one stage of the chilled water primary pump, the configuration is simple, and the excess is bypassed between the headers by controlling the chilled water flow rate on the air conditioning load side. It is an advantageous system that the temperature of the chilled water is basically stable. However, since a high flow rate flows in the header-to-header bypass and the chilled water primary pump is responsible for the entire head of the chilled water piping system, it is also a system in which optimum control as energy saving is difficult.
In the description of FIG. 2, the same elements as those of the heat source control system shown in FIG.

  The primary pump system is a piping system that circulates cold water to an air conditioner (AHU) using only the primary cold water pump. The heat source control system 100A shown in FIG. 2 does not have the second forward header 83, the secondary chilled water pumps 85a and 85b and the pipe line 87 shown in FIG. A pipe 39 is connected.

  As described above, in the heat source control system 100A shown in FIG. 2, 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.

(Comparative example of heat source control system control)
Next, a control example of the heat source control system shown in FIG. 3 will be described as a comparative example of the embodiment of the present invention.

  The processing in steps S101 to S103 shown in FIG. 3 shows processing in a prior simulation executed by a comparative computer different from the real-time controller 105. Also, the processing after step S104 shown in FIG. 3 is processing executed by the comparison type controller located at the same place as the real-time controller 105 of the heat source control system shown in FIG. 1 or FIG.

  First, the comparative form computer generates an optimum operation function of the composite heat source by a prior simulation (steps S101 to S103). In this simulation, the comparison form computer sets only the heat source unit 11 of each individual heat source unit 101 as a calculation target, and determines the refrigeration heat quantity Qc_R of the heat source unit 11 as a control variable (that is, an optimum control value obtained by a dependent function: a dependent variable). To do.

In step S101, the comparative form computer calculates the energy consumption amount of the composite heat source by the following equation (1).
Etotal = F (WB, Qc2, Qc_R [1-n]) ...... (1)
Here, “Etotal” is an evaluation value indicating the energy consumption of the composite heat source, and “F ()” returns the energy consumption (optimum control value) of the composite heat source for the condition substituted in parentheses. It is a function (dependent function). In addition, “WB” is a variable (independent variable) indicating the outside wet bulb temperature, “Qc2” is a variable (independent variable) indicating the load heat amount of the secondary cold water, and “Qc_R [i]” is the heat source device 11i. This is a variable indicating the amount of heat of freezing. Note that the symbol “i” is an argument that specifies any single heat source unit (or an element thereof) constituting the composite heat source, and takes an integer value within a range of 1-n in the present embodiment.

  In the simulation, the comparison form computer calculates the combination of Qc_R [1-n] such that the evaluation value Etotal takes the minimum value (optimum value) using the values of WB and Qc2 as constraint conditions (that is, independent variables).

  In this simulation, the comparative form computer calculates Qc_R [i] where the evaluation value Etotal takes the minimum value by changing the constraint condition Qc2 by 1% within a range of 0 to 100%. At this time, the number of heat source machines 11 to be operated is not limited to one. However, the operation order when operating the plurality of heat source units 11 is set in advance.

  Similarly, the comparative form computer sets five WBs of constraint conditions (for example, summer high temperature, summer low temperature, intermediate high temperature, intermediate low temperature, winter), and the evaluation value Etotal takes the minimum value Qc_R [i] is calculated. At this time, the number of heat source machines 11 to be operated is not limited to one. However, the operation order when operating the plurality of heat source units 11 is set in advance. The reason for limiting the number of WB patterns to five is that if the number of WB patterns is increased, the time and amount of calculation for the prior simulation become enormous.

In step S102, the comparison form computer calculates Qc_R [i] (or a combination of Qc_R [1-n]) at which the evaluation value Etotal takes the minimum value when changing the constraint condition Qc2 for each pattern of WB. It is converted into a function and output as the optimum operation function shown in Equation (2).
Qc_R [i] = Fop (Qc2) ...... (2)
Here, “Fop ()” is a function (dependent function) that returns a value of an optimal solution based on a simulation for a condition substituted in parentheses.

In step S103, since the optimal solution obtained by the above equation (2) is the generated refrigeration heat quantity (Qc_R [i]) of the heat source unit 11, the comparative form computer controls the equation (2) by the equation (3). Convert to the target cold water flow rate format.
Vc_R [i] = Qc_R [i] / Cpw · ρw · (Tc_in_R [i] -Tc_out_R [i]) = Qc_R [i] / Cpw · ρw · ΔTc_R [i] (3)
Here, “Vc_R [i]” is a variable indicating the cold water flow rate corresponding to the heat source device 11 i (that is, the cold water flow rate by the primary pump). “Cpw” is a physical constant indicating the specific heat of water, and “ρw” is a physical constant indicating the density of water. “Tc_in_R [i]” is a variable indicating the cold water inlet temperature of the heat source device 11i, and “Tc_out_R [i]” is a variable indicating the cold water outlet temperature of the heat source device 11i. “ΔTc_R [i]” is a variable indicating a temperature difference between the cold water inlet temperature and the cold water outlet temperature of the heat source device 11i.

  “Tc_in_R [i]” is a value of the cold water return temperature (temperature sensor 51) that changes in accordance with the operation status on the air conditioner 104 side (air conditioning load side), and is an unknown value in the preliminary simulation stage. is there. Therefore, in the example of FIG. 3, it is assumed that the comparative form computer incorporates ΔTc_R [i] in the calculation formula assuming a fixed value of 5 ° C. in the simulation.

By the above process, the computer (2) is transformed using the relationship of the formula (3), so that the comparison form computer obtains the optimum chilled water flow rate of each heat source unit shown in the formula (4) for each WB pattern. An operation function can be obtained. That is, in the example of FIG. 3, the optimal operation function for five patterns according to WB is generated by a prior simulation.
Vc_R [i] = Fop (Qc2) ...... (4)
In addition, the optimal operation function for every pattern calculated | required by said process will be stored in the memory | storage part of a comparison form controller.

  In step S104, the comparative form controller of the heat source control system 100 selects an optimum operation function to be used for control from among a plurality of patterns of optimum operation functions stored in the storage unit.

  For example, the comparison form controller acquires the date information from an internal timer (not shown), and selects the optimum operation function associated with the acquired date. As an example, the comparative form controller selects the optimal operation function at the summer high temperature in August, regardless of the actual outdoor wet bulb temperature, and selects the optimal operation function in winter in December.

  In step S105, the comparative form controller substitutes the measured value of the load heat quantity (Qc2) of the secondary chilled water in the optimum operation function selected in step S104, thereby controlling the control target value of the chilled water flow rate of the primary chilled water pump 12. Is calculated. Then, the comparative form controller controls the primary chilled water pump 12 of the heat source control system 100 based on the calculated control target value. Above, description of the comparative example shown in FIG. 3 is complete | finished.

(Control example of heat source control system of embodiment)
Next, a control example of the heat source control system shown in FIG. 4 will be described as an embodiment of the present invention. In the control example of the heat source control system shown in FIG. 4, it is possible to obtain four control target values at the same time by performing optimization in advance simulation and real-time control, and to calculate in real-time control. Highly accurate calculations are possible while greatly reducing the amount.

  The processes in steps S201 to S205 shown in FIG. 4 are processes in a prior simulation executed by a computer different from the real-time controller 105.

  Here, in the preliminary simulation of steps S201 to S205, the energy consumption of the three devices, that is, the heat source unit 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. Each optimization calculation is performed. In this optimization calculation, with WB, Qc_R [i], Tc_out_R [i] as constraint conditions (independent variables), cooling water amount and cooling tower fan airflow as control variables (dependent variables), and the constraint conditions are fixed, For various state values on the way to calculate control variables, temporarily calculate a part of the state value, change the remaining part, and repeat the calculation. An optimal solution that is a combination of (Vcd_CDP [i] and Vg_CT [i]) is calculated. In the preliminary simulation, the constraint condition is 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 obtaining minimum energy consumption of three devices", "Optimum operation function for cooling water flow rate", and "Optimum operation function for cooling tower airflow". To do.

  Hereinafter, the contents of the processing in steps S201 to S205 in FIG. 4 will be described in detail.

In step S201, the computer calculates the energy consumption amount of the heat source unit 11 in the single heat source unit 101, the cooling tower fan of the cooling tower 13 and the cooling water pump 14 for each single heat source unit 101 by the following equation (5). Perform optimization. This expression (5) is an expression generated for each individual heat source unit, and is the constraint condition (WB, Qc_R [i], Tc_out_R [i]) and control variables (Vcd_CDP [i], Vg_CT [i]). This formula summarizes the equations that output the energy consumption of the heat source unit, cooling tower, and cooling water pump in response to the input as a form of optimization problem and to solve the equation.
E_RCDPCT [i] = F _{E_RCDPCT [i]} (WB, Qc_R [i], Tc_out_R [i], Vcd_CDP [i], Vg_CT [i]) ...... (5)
Here, “E_RCDPCT [i]” is an evaluation value indicating the energy consumption of the three devices of the heat source unit 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 function that returns the energy consumption of the three devices of the heat source unit 11i, the cooling tower fan of the cooling tower 13i, and the cooling water pump 14i for the condition substituted in parentheses. is there. “Vcd_CDP [i]” is a variable indicating the cooling water flow rate of the cooling water pump 14i, and the amount of heat treated by the cooling water Qcd = the difference between the cooling tower inlet temperature and the cooling tower outlet temperature (cooling water ΔT) × cooling water flow rate. This relationship is self-evident, and the variable indicating the cooling water flow rate of the cooling water pump 14i may be replaced with the estimated 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, and the object to be controlled to approach the set value of the cooling water cooling tower outlet temperature in the cooling tower is the air volume of the cooling tower fan. It is obvious that there is a correlation between the amount of cooling tower fan airflow and the degree of approach to the cooling tower outlet temperature setting value, and the variable indicating the airflow of the cooling tower fan is replaced by the cooling tower outlet temperature setting value. There is also a case.

  That is, in the prior simulation, the computer in step S201 uses the values of WB, Qc_R [i] and Tc_out_R [i] as constraint conditions, and the control variable (evaluation value E_RCDPCT [i] takes the minimum value (optimum value)). An optimization operation for calculating a combination of Vcd_CDP [i] and Vg_CT [i]) as an optimal solution is performed.

  Specifically, the computer in step S201 performs optimization calculation for all patterns obtained by combining three constraint conditions by the following method.

  As an example, it is assumed that the WB of the constraint conditions changes in increments of 5 ° C. within a range of 2 to 27 ° C. and takes six values. Also, Qc_R [i] of the constraint conditions is assumed to change in 10% increments within a range of 10 to 100% and take 10 different values. In addition, Tc_out_R [i] of the constraint conditions is changed in increments of 0.5 ° C. within a range of 7 to 12 ° C. and takes 11 values. At this time, the combinations of the three constraint conditions are 660 types (6 × 10 × 11) patterns.

  Then, the computer selects one kind of combination of arbitrary constraint conditions, and under the selected combination of constraint conditions, the control variable whose evaluation value E_RCDPCT [i] according to the formula (5) takes the minimum value (optimum value) is selected. A combination (Vcd_CDP [i] and Vg_CT [i]) is calculated as an optimal solution. When calculating this evaluation value E_RCDPCT [i], the computer changes Vcd_CDP [i] in 10% increments in the range of 0 to 100% and Vg_CT [i] in 10% increments in the range of 0 to 100%. It shall be changed. With this optimization calculation, one control variable combination (Vcd_CDP [i] and Vg_CT [i]) that is an optimal solution is calculated for one selected combination of constraint conditions.

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

  In step S202, the computer calculates “minimum consumption of heat source device 11i, cooling tower 13i and 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 S201. An energy calculation function ”is generated. The “calculation function of the minimum energy consumption of the heat source unit 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 calculates the minimum consumption of the heat source device 11i, the cooling tower 13i, and the cooling water pump 14i from the three variables WB, Qc_R [i], Tc_out_R [i] based on the calculation result of the optimal solution in step S201. A function shown in Expression (6) for obtaining energy is generated.
E_RCDPCT_min [i] = F _{E_RCDPCT_min [i]} (WB, Qc_R [i], Tc_out_R [i]) …… (6)
Here, “E_RCDPCT_min [i]” is a variable indicating the minimum energy consumption of the heat source unit 11i, the cooling tower fan of the cooling tower 13i, and the cooling water pump 14i, and “ _{FE_RCDPCT_min [i]} ()” Based on the results, this is a function that returns the minimum energy consumption of the heat source device 11i, the cooling tower fan of the cooling tower 13i, and the cooling water pump 14i with respect to the variable substituted in the parenthesis.

  The “calculation function of the minimum energy consumption of the heat source device 11i, the cooling tower fan of the cooling tower 13i, and the cooling water pump 14i” generated in step S202 is an example of the first information. As described in step S201, the optimization calculation in the prior simulation is performed on each pattern of the combination of constraint conditions, and the minimum energy consumption of the three devices corresponding to each pattern is also obtained. Using this, the function of the first information is generated in the form of a data table in which the input of three constraint condition patterns and the output value indicating the minimum energy consumption in the pattern are associated with each other. The data table of the first information is stored in the storage unit 107 of the real-time controller 105.

  In step S203, the computer generates an “optimal operation function of the cooling water pump 14i” based on the calculation result of the optimal solution in the combination of WB, Qc_R [i] and Tc_out_R [i] in step S201. The “optimal operation function of the cooling water pump 14i” is generated for each individual heat source unit.

For example, based on the calculation result of the optimum solution in step S201, the computer obtains the cooling water flow rate of the cooling water pump 14i from three variables WB, Qc_R [i], Tc_out_R [i] (7 ) Is generated.
Vcd_CDP [i] = F _{Vcd_CDP [i]} (WB, Qc_R [i], Tc_out_R [i]) ...... (7)
Here, “F _{Vcd_CDP [i]} ()” is a function that returns the cooling water flow rate of the cooling water pump 14i with respect to the condition substituted in the parenthesis based on the calculation result of the optimal solution in step S201. is there.

  The “optimum operation function of the cooling water pump 14i” generated in step S203 is an example of the second information. As described in step S201, the optimization calculation in the prior simulation is performed for each pattern of the combination of constraint conditions, and the cooling water flow rate of the optimal solution corresponding to each pattern is also obtained. By using this, the function of the second information is generated in the form of a data table in which the input of the three constraint condition patterns and the output value indicating the coolant flow rate in the pattern are associated with each other. The data table of the second information is stored in the storage unit 107 of the real-time controller 105.

  In step S204, 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 S201. This “optimum operation function of the cooling tower 13i” is generated for each individual heat source unit.

For example, based on the calculation result of the optimal solution in step S201, the computer obtains the air flow rate of the cooling tower fan of the cooling tower 13i from the three variables WB, Qc_R [i], Tc_out_R [i] ( The function shown in 8) is generated.
Vg_CT [i] = F _{Vg_CT [i]} (WB, Qc_R [i], Tc_out_R [i]) ...... (8)
Here, “F _{Vg_CT [i]} ()” is a function that returns the air flow rate of the cooling tower fan of the cooling tower 13i for the condition substituted in the parenthesis based on the calculation result of the optimum solution in step S201. It is.

  The “optimum operation function of the cooling tower 13i” generated in step S203 is an example of third information. As described in step S201, the optimization calculation in the preliminary simulation is performed for each pattern of the combination of constraint conditions, and the air volume of the cooling tower of the optimal solution corresponding to each pattern is also obtained. Using this, the function of the third information is generated in the form of a data table in which the input of the three constraint condition patterns and the output value indicating the air flow rate of the cooling tower fan in the pattern are associated with each other. The The data table of the third information is stored in the storage unit 107 of the real-time controller 105.

  Note that the data tables of the first information to the third information are simultaneously determined based on the result of the optimization operation in S201. Further, in the data table of the first information to the third information generated in S202 to S204, the increment of each variable of WB, Qc_R [i] and Tc_out_R [i] is discrete, and is limited on the data table. Output value information is held only for the WB, Qc_R [i] and Tc_out_R [i] patterns. For this reason, during the real-time control described later, when information on the minimum energy consumption corresponding to a place where there is no step in the variable is required on the data table, the real-time controller 105 uses the output value of the data table to make a known three-dimensional linear By performing the interpolation, an output value corresponding to a desired variable is obtained.

  In step S205, the computer determines whether each function of steps S202 to S204 has been generated for all the single heat source units 101. When each function of steps S202 to S204 is generated for all the single heat source units 101 (YES), the computer ends the previous simulation process. On the other hand, when each function of Steps S202 to S204 is not generated for any single heat source unit 101 (NO), the process returns to Step S201, and the computer repeats the above processing. By the loop of steps S201 to S205, the functions of steps S202 to S204 are generated for the individual heat source units 101 (1) to 101 (n) during the simulation.

  And the process after step S206 of the control example shown in FIG. 4 is a process at the time of the real-time control performed by the real-time controller 105 of the heat source control system 100 shown in FIG. 1 or FIG.

  In the real-time control of the heat source control system 100, the real-time controller 105 uses the first information described above to form the energy consumption of the entire system of the composite heat source into the form of an optimization problem equation. Then, the real-time controller 105 performs optimization so that the energy consumption of the composite heat source is minimized by using WB, Vc2, Tcr2 as constraint conditions and Vc_R [1-n], Tc_out_R [1-n] as control variables. Calculation is performed with the flow rate and the chilled water outlet temperature as the optimal solution and the control target value. The real-time controller 105 controls the amount of refrigeration by assuming that the inlet temperature difference is constant with chiller chilled water by using real-time measurement values and operation state information instead of pre-estimated values for calculation input during real-time control. It is possible to perform highly accurate optimization using the temperature and flow rate as the amount of freezing heat as control variables, compared to the case of using variables. In step S201, the computer executes only six values of 5 ° C. change in the outside air wet bulb temperature WB in the range of 2 to 27 ° C. in the constraint condition. In addition, since real-time outdoor wet bulb temperature measurement values are substituted instead of the six presumed values, it is possible to perform highly accurate optimization.

  In other words, the computer that performs the preliminary simulation creates the data table function by executing only the six values of the outside wet bulb temperature WB in the constraint condition, for example, in the range of 2 to 27 ° C. with 5 ° C. increments. However, since a real-time outdoor wet-bulb temperature measurement value is substituted for the calculation input at the time of real-time control instead of the six presumed values, a 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-described second information to calculate the WB, Qc_R [i], Tc_out_R [i] from the optimum operation function of the cooling water flow rate. A calculation for obtaining a control target value of the coolant flow rate is performed. Similarly, in the real-time control of the heat source control system 100, the real-time controller 105 uses the third information described above, and uses WB, Qc_R [i], Tc_out_R [i] as function inputs, and an optimal operation function of the cooling tower air volume To calculate the control target value of the cooling tower air volume.

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

  Hereinafter, the contents of the processing after step S206 in FIG. 4 will be described in detail.

In step S206, the real-time controller 105 of the heat source control system 100 optimizes the energy consumption amount of the composite heat source by the following equation (9).
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]) ...... (9)
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 with respect to the condition substituted in parentheses. It is a function that returns the energy consumption. “F _Etotal ()” is a function that returns the energy consumption of the composite heat source for the condition substituted 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 S206, the real-time controller 105 substitutes the measured values of the sensors for the constraint conditions WB, Vc2 and Tcr2, and the control variables Vc_R [1-n] and Tc_out_R [1- n] is obtained in real time.

  The equation for obtaining the energy consumption amount of each individual heat source unit 101i is the equation (first equation) for obtaining the minimum energy consumption of the heat source unit 11i, the cooling tower fan of the cooling tower 13i, and the cooling water pump 14i. (6) and the formula (second formula) for obtaining the energy consumption of the primary chilled water pump 12 can be derived (the formula for obtaining the energy consumption amount in each individual heat source unit 101i). Also referred to as the third equation).

  And the energy consumption in a composite heat source determines the combination of the single heat source unit 101 (1) -101 (n) to operate from a composite heat source, and operates the single heat source unit 101 (1) -101 (n) By summing up the energy consumptions of (9), it can be summarized as in the top row of equation (9). In summary, the energy consumption amount in the composite heat source can be expressed in the form of an optimization problem as shown in the bottom row of Equation (9). Note that the process of organizing equation (9) is omitted.

  When the formula (9) is derived based on the above idea and the optimization calculation based on the formula (9) is performed so that the total value of energy consumption in 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 units 11 (1) to 11 (n), respectively, as the optimum solution.

  For example, the real-time controller 105 obtains a combination of control variables Vc_R [1-n] and Tc_out_R [1-n] for which the evaluation value Etotal is the minimum value (optimum value) when the constraint conditions are WB, Vc2, and Tcr2. . In the optimization calculation at the time of real-time control, the constraint condition to be an expression input is uniquely determined according to the situation at the time of real-time control. In other words, the real-time controller 105 substitutes the measured values of the sensors for the constraint conditions WB, Vc2 and Tcr2, and a combination of the control variables Vc_R [1-n] and Tc_out_R [1-n] where the evaluation value Etotal is the optimum value. In real time. For the heat source unit 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 optimal calculation can be performed in real time using the operating conditions of each refrigerator and each individual heat source, and the optimal calculation assuming the number of operating units and the operating sequence in advance is not necessary. Optimal operation with only the refrigerator is possible in a form that can be easily processed.

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

  In step S207, the real-time controller 105 uses the data table of the “optimum operation function of the cooling water pump 14i” generated in step S203 to control the cooling water flow rate control target value (Vcd_CDP [1-n ]). At this time, the real-time controller 105 substitutes the measured value of the sensor for WB, Qc_R [i], Tc_out_R [i] as function inputs, and obtains the control target value (Vcd_CDP [1-n]) in real time. When the actual amount of “Vcd_CDP [i]”, which is the calculation result, is the coolant flow rate, it is proportional to the coolant pump inverter frequency, and when the actual amount of “Vcd_CDP [i]” is the estimated value of coolant ΔT , “Cooling water outlet temperature set value = Refrigerator cooling water inlet temperature measured value (need to be measured to prevent freezer operation trouble) + Cooling water ΔT assumed value” and chiller cooling water outlet temperature measurement The variable flow rate control of the cooling water pump is performed so that the value becomes the cooling water outlet temperature set value. The former is the calculation logic itself, but it manages only the flow rate of the heat medium and does not directly control the temperature field. Since the flow rate is managed, the flow rate suitable for the load can be managed. By using the latter ΔT as a representative value, if the cooling water outlet temperature in the condenser of the refrigerator decreases, the pressure difference with the evaporator may become too small, and the periphery of the compressor to prevent compressed gas leakage The circulation of the lubricating oil, which also fills the gaps in the metal casing, causes stagnation and burn-in, but the actual amount of "Vcd_CDP [i]" that is the calculation result can also have a function to prevent this. .

Here, the value of Qc_R [i], which is the input of the function in step S207, is obtained from the following equation (10).
Qc_R [i] = Cpw ・ ρw ・ Vc_R [i] ・ (Tc_in_R [i] -Tc_out_R [i]) (10)
Here, “Vc_R [i]” and “Tc_out_R [i]” in Equation (10) are both the calculation results in step S206. Further, “Tc_in_R [i]” in Expression (10) 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 S208, the real-time controller 105 uses the data table of the “optimum operation function of the cooling tower fan of the cooling tower 13i” generated in step S204 to control the air volume control target value (Vg_CT [1-n ]). At this time, the real-time controller substitutes the measured value of the sensor for WB, Qc_R [i], Tc_out_R [i], which are function inputs, and obtains the control target value (Vg_CT [1-n]) in real time. When the actual amount of the calculation result “Vg_CT [i]” is the cooling tower air volume, it is proportional to the cooling tower air volume fan inverter frequency, and the actual amount of “Vg_CT [i]” is the cooling tower outlet temperature setting value. In this case, the cooling tower fan variable air volume 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 setting value to the refrigerator, and when the cooling water inlet temperature in the refrigerator condenser decreases, the pressure difference with the evaporator becomes too small In some cases, the circulation of lubricating oil to prevent leakage of compressed gas may cause stagnation and burn-in, or if the cooling water inlet temperature in the condenser of the refrigerator rises too much, the condenser will become an abnormally high pressure However, the actual amount of “Vg_CT [i]” that is the calculation result can also have a function of preventing these.
In step S208, the method for calculating Qc_R [i] is the same as in step S207.

  Thus, 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. Above, description of the control example shown in FIG. 4 is complete | finished.

  Hereinafter, operational effects of the control example of the present embodiment will be described.

  First, in the control of the present embodiment shown in FIG. 4, among the elements of the single heat source unit 101, the heat source machine 11 and the cooling tower 13, which are problems of only the amount of heat without considering the secondary side temperature difference ΔT and the flow rate of the cold water. The case of the energy consumption of the cooling water pump 14 and the case of the energy consumption of the primary chilled water pump 12 that needs to consider the flow rate of the chilled water from the amount of heat due to the temperature difference ΔT on the secondary side are considered separately.

  Since the former can be simulated in advance, the prior calculation by simulation is preferable from the viewpoint of reducing the calculation load in real-time control. On the other hand, for the latter, the value of ΔT changes sequentially according to the operating condition on the secondary side, and it is very difficult to specify in advance simulation, but it is sufficient to use the measured value when calculating in real time. In real-time control, the identification is easy.

  Regarding the former, based on a prior simulation, “calculation function of minimum energy consumption of heat source unit 11, cooling tower fan of cooling tower 13 and cooling water pump 14”, “optimum operation function of cooling water pump 14”, “cooling tower” The data table of “13 optimum operation functions” is generated (S201 to S204). Then, the real-time controller 105 inputs the measured values to the data table of these functions to thereby determine the minimum energy consumption of the heat source device 11, the cooling tower 13, and the cooling water pump 14, the control target value (Vcd_CDP [1-n], Vg_CT [1-n]) is obtained in real time (S206 to S208).

  For the latter, the real-time controller 105 obtains the energy consumption of the primary chilled water pump 12 by real-time calculation without creating a table by a prior simulation (S206). Then, the real-time controller 105 totals the minimum energy consumption of the heat source unit 11, the cooling tower fan of the cooling tower 13 and the cooling water pump 14 obtained from the data table, and the energy consumption of the primary chilled water pump 12 obtained by real-time calculation. Thus, an expression for obtaining the energy consumption is generated for each individual heat source unit 101 (S206). As a result, according to the present embodiment, by performing the optimization calculation by decomposing the flow rate and temperature as described above, while suppressing the amount of calculation and the data amount of the data table in advance simulation and real-time control Thus, it is possible to perform optimal control for calculating a control target value with higher accuracy than in the past.

  In the present embodiment, the measured values of the inlet temperature and the measured values and the calculated values of the outlet temperature are used to calculate the outdoor air wet bulb temperature and the inlet / outlet temperature difference ΔT of the refrigerator cold water. Therefore, these parameters are fixed values. Optimal control for calculating a control target value with higher accuracy than in the case is possible.

  Furthermore, in the control of this embodiment shown in FIG. 4, the optimization of the single heat source unit 101 is partially performed by a prior simulation, but the optimization calculation for the entire composite heat source is executed in real time (S206). ). Therefore, the real-time controller 105 can perform optimization by excluding the single heat source unit 101 that cannot be operated at the time of calculation, and can freely set the number of operating units and the operating order of the single heat source units 101. In addition, optimization calculations for the entire combined heat source can be executed in real time, and the chilled water supply temperature to the air conditioning load can be calculated and determined. Therefore, the chilled water outlet temperature for each individual heat source unit 101 can be determined based on the minimum energy consumption standard. It becomes possible to change. In other words, the calculation is performed so that the chilled water supply temperature to the air conditioning load targeted by the sum of the chilled water outlet temperature of each individual heat source and the chilled water flow rate is obtained. In addition, since this calculation is possible, the chilled water outlet temperature for each individual heat source unit 101 is changed based on the minimum energy consumption standards from the measured values of the chilled water supply temperature, chilled water return temperature, and chilled water flow rate on the air conditioning load side in real time. This makes it possible to perform optimal control while minimizing the header bypass flow rate.

(Supplementary items of the embodiment)
In the description of the above embodiment, the calculation example for optimizing the energy consumption amount in the heat source control system has been described as an example of the optimal control of the heat source. However, the present invention can be similarly applied to calculation of optimal control in which a control target value is calculated so that other indices such as CO ₂ emission amount and cost are reduced in the heat source control system.

  From the above detailed description, features and advantages of the embodiments will become apparent. It is intended that the scope of the claims extend to the features and advantages of the embodiments as described above without departing from the spirit and scope of the right. Also, any improvement and modification should be readily conceivable by those having ordinary knowledge in the art. Therefore, there is no intention to limit the scope of the inventive embodiments to those described above, and appropriate modifications and equivalents included in the scope disclosed in the embodiments can be used.

DESCRIPTION OF SYMBOLS 11 ... Refrigerator (heat source machine R), 12 ... Primary chilled water pump, 13 ... Cooling tower, 14 ... Cooling water pump, 100 ... Heat source control system, 101 ... Single heat source unit, 102 ... Out header, 103 ... Return header, 104 ... Air conditioner (AHU), 105 ... Real-time controller, 106 ... Outside temperature / humidity sensor, 107 ... Storage unit

Claims (2)

An air conditioning load located on the secondary side formed by an air conditioner group or a water / air heat exchanger group that exchanges heat with air; and
A forward header for sending cold water toward the air conditioning load;
A return header for receiving cold water sent from the air conditioning load;
A plurality of single heat source units each connected to the forward header via a cold water primary forward pipe and to the return header via a cold water primary return pipe;
A control unit that includes a storage unit and controls the plurality of single heat source units;
With
Each of the single heat source units
A primary chilled water pump which is connected to the return header via a chilled water primary return pipe, gives a flow rate to the chilled water in the pipe and sends it out, and also controls the flow rate of the chilled water, and the primary chilled water pump of the chilled water primary return pipe The cold water sent from the primary chilled water pump connected to the downstream side of the chilled water, the heat source machine connected to the forward header via the chilled water primary outgoing pipe downstream of itself, and the result of the cold water refrigeration of the heat source machine Cooling water circulating to transfer exhaust heat between the cooling tower and the heat source unit, a cooling tower having a cooling tower fan for transferring the outside air, which cools the generated exhaust heat by heat exchange with the outside air A cooling water pump for controlling the flow rate,
The storage unit
Information generated in each of the individual heat source units, the temperature of the outside wet bulb, the amount of heat generated by the heat source unit and the cold water outlet temperature of the heat source unit, the heat source unit of the single heat source unit, the cooling tower First information indicating a correspondence relationship between the minimum energy consumption of the fan and the cooling water pump;
Information generated in each of the individual heat source units, including an outside wet bulb temperature, a generated heat amount of the heat source unit, a cold water outlet temperature of the heat source unit, and a control target value of a cooling water flow rate by the cooling water pump. Second information indicating a correspondence relationship;
Information generated in each of the individual heat source units, and the correspondence relationship between the outside wet bulb temperature, the heat generation amount of the heat source unit, the cold water outlet temperature of the heat source unit, and the control target value of the air amount of the cooling tower fan 3rd information indicating
The controller is
Consumption of the primary chilled water pump based on the first equation for obtaining the minimum energy consumption of the heat source unit, the cooling tower fan and the cooling water pump using the first information and the flow rate of chilled water to the heat source unit By summing the second equation for obtaining energy, a third equation for obtaining energy consumption of the single heat source unit is generated,
A plurality of third equations corresponding to each of the individual heat source units are used to calculate the measured values of the outdoor wet bulb temperature, the generated heat amount of the heat source unit, and the chilled water outlet temperature of the heat source unit that are continuously acquired during operation at a predetermined sampling time. For each of the individual heat source units, and an optimization calculation for obtaining the control target value of the cold water flow rate and the control target value of the cold water outlet temperature of the single heat source unit so that the total value of the energy consumption in each of the single heat source units is minimized. Run in real time during operation,
The cooling water of the single heat source unit using the second information based on the value of the outdoor wet bulb temperature acquired at a predetermined sampling time during operation, the amount of heat generated by the heat source unit, and the cold water outlet temperature of the heat source unit Find the control target value of the coolant flow rate of the pump,
The cooling tower of the single heat source unit using the third information based on the value of the outdoor wet bulb temperature acquired at a predetermined sampling time during operation, the amount of generated heat of the heat source unit, and the value of the cold water outlet temperature of the heat source unit A heat source control system characterized by obtaining a control target value of fan air volume. An air conditioning load located on the secondary side formed by an air conditioner group or a water / air heat exchanger group that exchanges heat with air; and
A forward header for sending cold water toward the air conditioning load;
A return header for receiving cold water sent from the air conditioning load;
A plurality of single heat source units each connected to the forward header via a cold water primary forward pipe and to the return header via a cold water primary return pipe;
A control device for controlling a plurality of the individual heat source units;
With
Each of the single heat source units
A primary chilled water pump which is connected to the return header via a chilled water primary return pipe, gives a flow rate to the chilled water in the pipe and sends it out, and also controls the flow rate of the chilled water, and the primary chilled water pump of the chilled water primary return pipe The cold water sent from the primary chilled water pump connected to the downstream side of the chilled water, the heat source machine connected to the forward header via the chilled water primary outgoing pipe downstream of itself, and the result of the cold water refrigeration of the heat source machine Cooling water circulating to transfer exhaust heat between the cooling tower and the heat source unit, a cooling tower having a cooling tower fan for transferring the outside air, which cools the generated exhaust heat by heat exchange with the outside air A control method of a heat source control system including a cooling water pump for controlling a flow rate,
According to the simulation before operation, for each of the single heat source units, the outside air wet bulb temperature, the generated heat amount of the heat source unit and the cold water outlet temperature of the heat source unit, the heat source unit of the single heat source unit, the cooling tower fan And generating first information indicating a correspondence relationship with the minimum energy consumption of the cooling water pump,
Correspondence between the outdoor heat wet bulb temperature, the heat generation amount of the heat source unit, the cold water outlet temperature of the heat source unit, and the control target value of the cooling water flow rate by the cooling water pump, for each of the individual heat source units by the simulation before operation Generating second information indicating the relationship;
Based on the simulation before operation, for each of the individual heat source units, the correspondence relationship between the outside wet bulb temperature, the heat generation amount of the heat source unit, the cold water outlet temperature of the heat source unit, and the control target value of the air amount of the cooling tower fan is determined. Generate third information to indicate
When the control device performs real-time control during operation,
Consumption of the primary chilled water pump based on the first equation for obtaining the minimum energy consumption of the heat source unit, the cooling tower fan and the cooling water pump using the first information and the flow rate of chilled water to the heat source unit By summing the second equation for obtaining energy, a third equation for obtaining energy consumption of the single heat source unit is generated,
A plurality of third equations corresponding to each of the individual heat source units are used to calculate the measured values of the outdoor wet bulb temperature, the heat generation amount of the heat source unit, and the cold water outlet temperature of the heat source unit that are continuously acquired during operation at a predetermined sampling time. For each of the individual heat source units, and an optimization calculation for obtaining the control target value of the cold water flow rate and the control target value of the cold water outlet temperature of the single heat source unit so that the total value of the energy consumption in each of the single heat source units is minimized. Run,
The cooling water of the single heat source unit using the second information based on the value of the outdoor wet bulb temperature acquired at a predetermined sampling time during operation, the amount of heat generated by the heat source unit, and the cold water outlet temperature of the heat source unit Find the control target value of the coolant flow rate of the pump,
The cooling tower of the single heat source unit using the third information based on the value of the outdoor wet bulb temperature acquired at a predetermined sampling time during operation, the amount of generated heat of the heat source unit, and the value of the cold water outlet temperature of the heat source unit A control method of a heat source control system, characterized in that a control target value of a fan air volume is obtained.

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