JP2001221482A - Heating cooling system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a heating/cooling system having excellent economy and energy saving performance by supplying heating medium for optimal heating/ cooling depending on the variation of load conditions of a building. SOLUTION: The heating/cooling system comprises a hot and chilled water generator 11 and a hot and chilled water primary pump 12 for supplying hot and chilled water to an air conditioner 13 and a hot and chilled water secondary pump 14, a bypass pipe 19 coupling a water supply pipe 20 and a water return pipe 21, a thermal storage tank 34 and a radiation pump 35 for supplying hot and chilled water to the air conditioner 13 and the hot and chilled water secondary pump 14 through a heat exchanger 33 provided in the load side water supply pipe 20 or water return pipe 21, and a heat source controller 26 for controlling to circulate the hot and chilled water.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cooling / heating system for optimally supplying a heating / cooling heating medium in response to a change in a load state of a building.

[0002]

2. Description of the Related Art FIG. 9 is an explanatory diagram showing an example of a conventional cooling and heating system, and FIGS. 10 and 11 are flow charts showing a unit control operation and a variable flow control operation in the conventional cooling and heating system, respectively.

In the cooling and heating system shown in FIG. 9, a cold / hot water generator 11 is provided as a heat source side device, and a plurality of cold / hot water primary pumps 12 are provided in parallel as a heat source side cold / hot water transport device, and an air conditioner 13 is provided as a load side device. A cold / hot water secondary pump 14 is provided as a side cold / hot water transport device. The cold / hot water primary pump 12 and the cold / hot water secondary pump 14 are provided with a pump variable flow control device 15 for varying the discharge amount. 1
Reference numerals 6 and 17 denote primary and secondary headers for mixing cold or hot water from the cold / hot water generator 11, respectively.
Reference numeral 18 denotes a return header for mixing cold water or hot water returning to the cold / hot water generator 11. The bypass pipe 19 is provided to connect the water supply pipe 20 and the return water pipe 21, preferably to connect the outgoing primary header 16 and the return water pipe 21, or to connect the outgoing primary header 16 and the return header 18. 22 is a water supply temperature sensor for measuring the water supply temperature to the air conditioner 13,
23 is a return water temperature sensor for measuring the return water temperature from the air conditioner 13, and 24 and 25 are flow meters for measuring the load flow rate and the bypass flow rate, respectively. Reference numeral 10 denotes a pressure sensor for measuring the water supply pressure on the load side.

The cold or hot water produced by the cold / hot water generator 11 is pumped by a cold / hot water primary pump 12 to an outgoing primary header 16, and is further fed by a cold / hot water secondary pump 14 to an outgoing secondary header 17 and a water pipe 20. Air conditioner 1 via
It is pumped to 3. The cold or hot water sent to the air conditioner 13 exchanges heat with the air conditioner 13 and then returns to the cold / hot water generator 11 again via the return header 18 and the return water pipe 21. The cooling / heating load conveyed to the cold / hot water generator 11 is discharged to the outside via a cooling water pump and a cooling tower (not shown) of the cooling water circuit. At this time, when the flow rate of the cold or hot water conveyed by the cold / hot water primary pump 12 and the flow rate of the cold or hot water conveyed by the cold / hot water secondary pump 14 are balanced, the flow rate of the bypass pipe 19 becomes zero, but the former is zero. Is larger than the latter, a flow is formed in the bypass pipe 19 from the outgoing primary header 16 to the return water pipe 21. Conversely, if the latter is larger than the former, the flow from the return pipe 21 to the bypass pipe 19 is forwarded from the return pipe 21. A flow towards the header 16 is formed. From the viewpoint of energy saving, an operation in which the bypass pipe flow rate becomes zero is desirable.

[0005] Reference numeral 26 denotes a heat source control device for optimally controlling the cold / hot water generator 11, the cold / hot water primary pump 12, and the cold / hot water secondary pump 14 according to the change in the load condition of the air conditioner 13.
The heat source control device 26 includes a load measuring unit 27 that measures a current load state, a bypass pipe flow measuring unit 28 that measures a current bypass pipe flow rate, and operation of the cold / hot water generator 11 and the cold / hot water secondary pump 14. The control unit 29 controls the number of units and the control signals of the cold / hot water primary pump 12 and the cold / hot water secondary pump 14, and the cold / hot water generator 11, the cold / hot water primary pump 12, and the cold / hot water secondary pump 14. A control output unit 30 that outputs a control signal is mounted. If necessary,
In some cases, the load prediction unit 31 that predicts future changes in the load state is mounted on the heat source control device 26.

The control of the number of cooling and heating systems is performed as shown in a flowchart of FIG. That is, for example, when the index indicating the load state is the load calorie, the load measuring unit 27 of the heat source control device 26 uses the water supply temperature sensor 2
2. The operating state of the cooling and heating system is acquired using the feed water temperature, the return water temperature, and the load flow rate, which are the values measured by the return water temperature sensor 23 and the flow meter 24, and the current load heat amount (load heat amount =
(Load flow rate x return water temperature difference) and, if necessary, the load predictor 31 linearly regresses the load calorie (regression range) from the current time to a specified time before, and designates it from the present based on this. The load calorie after time (forecasting target) is predicted. Then, by collating the determination formula of each increase / decrease stage request that defines the correspondence between the measured load heat amount or the predicted load heat amount and the number of operating chilled / hot water generators, the chilled / hot water generator 11 corresponding to the load state is checked. Decide the number of operating units. When the determined operating number is different from the current operating number in comparison with the current operating number, the heat source control device 26 controls the chilled / hot water generator 11 through the number control / variable flow rate control calculation unit 29 and the control output unit 30. Perform step-up or step-down. In addition, the number control / variable flow control calculation unit 29 calculates the number of operating cold / hot water secondary pumps 14 according to the load state in the same manner as in the case of the cold / hot water generator 11, and outputs the cold / hot water through the control output unit 30. The control of the secondary pump 14 is performed.

The variable flow rate control of the cooling and heating system is performed by controlling the number of units.
This is performed in the variable flow control calculation unit 29 as shown in the flowchart of FIG. That is, when performing the variable flow rate control calculation of the cold / hot water primary pump 12, the bypass pipe flow rate is measured using the measurement value of the flow meter 25, and the preset bypass pipe flow rate target value is acquired. The pump operation amount is determined after the calculation of the pump operation amount by the PID control based on the PID control and the upper and lower limit check thereof are performed. In this calculation process, the control output of the cold / hot water primary pump 12 is normally calculated so that the bypass pipe flow rate becomes zero. In addition, when performing the variable flow control calculation of the cold / hot water secondary pump 14, the water supply pressure is measured using the measurement value of the pressure sensor 10, and a preset water supply pressure target value is obtained, and based on this target value. After the operation of the cold / hot water secondary pump operation amount by PID control and upper / lower limit check thereof are performed, the pump operation amount is determined. In this calculation process,
Normally, the control output of the cold / hot water secondary pump 14 is calculated so that the water supply pressure becomes a value determined according to the change in the load state. Then, based on the calculated control outputs, the variable flow rate control of the cold / hot water primary pump 12 and the cold / hot water secondary pump 14 is performed via the control output unit 30 and the pump variable flow rate control device 15.

[0008]

In a conventional cooling and heating system, by supplying cold and hot water in accordance with the cooling and heating load on the load side, not only the load-side cold and hot water transfer device but also the heat source-side cold and hot water transfer device is supplied with power. On the other hand, if the flow rate of the cold and hot water passing through the cold and hot water generator becomes too small, the refrigeration cycle becomes unstable and the cold and hot water generator becomes abnormal. During this time, it was necessary to control the heat-source-side cold / hot water transfer device so as to secure a predetermined minimum flow rate. For this reason, when the load side has a low load, that is, when the load required on the load side is lower than the minimum flow rate of the chilled / hot water generator, the discharge amount of the heat source side chilled / hot water transfer device is reduced to the load side. Since the discharge amount becomes larger than the discharge amount of the cold / hot water transport device, wasteful cold / hot water returning to the cold / hot water generator via the bypass pipe occurs, and there is a problem that the reduction of the transport power is not sufficiently achieved.

The present invention has been made in view of the above circumstances, and provides a cooling and heating system which is excellent in economic efficiency and energy saving by supplying a heating medium for cooling and heating optimally in accordance with a change in the load state of a building. The purpose is to do.

[0010]

SUMMARY OF THE INVENTION To achieve the above object, the present invention relates to a cooling and heating system for cooling and heating a building by circulating and supplying cooling and heating water, comprising a load-side device for processing a cooling and heating load and a load-side cooling and heating system. A water transport device, a first heat source-side device and a heat source-side cold / hot water transport device for supplying cold / hot water to the load-side device and the load-side cold / hot water transport device, and a water supply-side pipeline and a return water-side pipeline are connected. A second heat source side for supplying cold / hot water to the load-side device and the load-side cold / hot water transfer device via a bypass pipe and a heat exchanger provided on a load-side water-supply-side pipe or a return-water-side pipe; Device and a heat source side cold and hot water transport device, and a heat source control device that controls so as to circulate and supply the cold and hot water, the heat source control device detects at least the cooling and heating load and the bypass pipe flow rate, and 1 heat source side package And a first control output calculator for calculating a control output with respect to the heat source side hot and cold water conveying device, by detecting at least the cooling and heating load and the load-side supply water temperature,
A second control output calculator for calculating a control output for the second heat source side device and the heat source side chilled / hot water transfer device; and a control output from the first control output calculator or the second control output calculator. And a control output unit that outputs an actual control signal.

The present invention also relates to a cooling and heating system for cooling and heating a building by circulating and supplying cold and hot water, comprising a load-side device for processing a cooling and heating load and a load-side cold and hot water transport device.
A first heat source-side device and a heat source-side cold / hot water transport device for supplying cold / hot water to the load-side device and the load-side cold / hot water transport device; a bypass pipe connecting a water supply-side pipeline and a return water-side pipeline; A load-side sub-pipe provided in parallel with a part of a water-supply-side pipe or a return-side pipe on the side, a switching means for switching a flow path of cold / hot water on the load side to the load-side sub-pipe, A second heat source-side device and a heat source-side cold / hot water transport device for supplying cold / hot water to the load-side device and the load-side cold / hot water transport device via a heat exchanger provided in the sub-pipe; A heat source control device for performing control so that the heat source control device detects at least the cooling / heating load and the bypass pipe flow rate, and outputs a control output to the first heat source side device and the heat source side cold / hot water transport device. The first to compute A control output calculation unit, a second control output calculation unit that detects at least the cooling / heating load and the load side water supply temperature, and calculates a control output to the second heat source side device and the heat source side cold / hot water transport device; A control output unit that outputs a control output from the first control output calculation unit or the second control output calculation unit as an actual control signal.

[0012] In the cooling and heating system, the heat source control device may be configured to stop the first heat source device and the heat source side cold / hot water transport device when the cooling / heating load falls below a predetermined lower limit. The control output of the control output calculation unit is output as an actual control signal, and the bypass pipe is used as a part of a water supply side pipe or a return water side pipe to circulate and supply cold and hot water to cool and heat the building. It is characterized by performing.

In the cooling and heating system, the heat source control device may operate the second heat source side device and the heat source side cold and hot water transport device when the cooling and heating load exceeds a predetermined upper limit, and And outputting the control output from the control output calculation section and the control output from the second control output calculation section as actual control signals.

Further, the present invention is characterized in that in the cooling and heating system, the second heat source side device and the heat source side cold / hot water transport device are a cooling tower and a cooling water pump.

Further, the present invention is characterized in that in the cooling and heating system, the second heat source side device is a heat pump or a heat storage tank.

[0016]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below in detail with reference to the drawings. In the drawings, the same portions are denoted by the same reference numerals and description thereof will be omitted.

FIG. 1 is an explanatory view showing a configuration of a cooling and heating system according to a first embodiment of the present invention. FIGS. 2, 3, and 4 are cooling and heating systems according to the first embodiment of the present invention, respectively. 3 is a flowchart for explaining the number control operation, variable flow control operation, and low load control operation.

In FIG. 1, reference numeral 11 denotes a cold / hot water generator;
Is a cold / hot water primary pump, 13 is an air conditioner, and 14 is a cold / hot water secondary pump. A plurality of cold / hot water generators 11 are provided in parallel, and a cold / hot water primary pump 12 is provided for each. Reference numerals 16 and 17 denote a primary header and a secondary header, respectively, for mixing cold or hot water from the cold / hot water generator 11, and reference numeral 18 denotes a return header for mixing cold or hot water returning to the cold / hot water generator 11. The bypass pipe 19 is
The outgoing primary header 16 and the return water pipe 21 or the outgoing primary header 16 and the return header 18 are connected to each other. A heat exchanger 33 is provided in the return water pipe 21 on the load side,
A heat storage tank 34 and a radiation pump 35 are provided via the heat exchanger 33. Reference numeral 15 denotes a pump variable flow control device, which is a cold / hot water primary pump 12 and a cold / hot water secondary pump 14.
And the heat radiation pump 35. 22 is a water supply temperature sensor for measuring the water supply temperature to the air conditioner 13;
3 is a return water temperature sensor for measuring the return water temperature from the air conditioner 13, and 24 and 25 are flow meters for measuring the load flow rate and the bypass flow rate, respectively. Reference numeral 10 denotes a pressure sensor for measuring the water supply pressure on the load side.

In this embodiment, the first heat-source-side device and the heat-source-side cold / hot water transport device are a cold / hot-water generator 11 and a cold / hot water primary pump 12, and the second heat source-side device and the heat source-side cold / hot water transport device. Is the heat storage tank 34 and the heat radiation pump 3
5 Among these devices, when the cooling / heating load is not low, the cold / hot water generator 11 and the cold / hot water primary pump 1
2 operates and when the cooling / heating load is low, the heat storage tank 3
4 and the heat radiation pump 35 operate.

A cold / hot water generator 11 and a cold / hot water primary pump 1 which are a first heat source side device and a heat source side cold / hot water transfer device
The operation of the air-conditioning system when operating the air conditioner 2 is as follows. That is, the cold or hot water generated by the cold / hot water generator 11 is pumped by the cold / hot water primary pump 12 to the outgoing primary header 16, and further cooled / hot water secondary pump 14.
Is sent to the air conditioner 13 via the outgoing secondary header 17 and the water pipe 20. The cold or hot water sent to the air conditioner 13 exchanges heat with the air conditioner 13 and then returns to the return header 18.
And it returns to the cold / hot water generator 11 again via the return water pipe 21. The cooling / heating load conveyed to the cold / hot water generator 11 is discharged to the outside via a cooling water pump and a cooling tower (not shown) of the cooling water circuit. At this time, when the flow rate of the cold or hot water conveyed by the cold / hot water primary pump 12 and the flow rate of the cold or hot water conveyed by the cold / hot water secondary pump 14 are balanced, the flow rate of the bypass pipe 19 becomes zero, but the former is zero. Is larger than the latter, a flow is formed in the bypass pipe 19 from the outgoing primary header 16 to the return water pipe 21. Conversely, if the latter is larger than the former, the flow from the return pipe 21 to the bypass pipe 19 is forwarded from the return pipe 21. A flow towards the header 16 is formed.

On the other hand, the operation of the cooling and heating system when operating the heat storage tank 34 and the radiating pump 35 as the second heat source side device and the heat source side cold / hot water transfer device is as follows. That is, the cold water or hot water stored in the heat storage tank 34 is sent to the heat exchanger 33 by the heat radiation pump 35 and exchanges heat with the cold water or hot water flowing through the return water pipe 21, and then returns to the heat storage tank 34 again. Return water pipe 2 through heat exchanger 33
The cold water or hot water produced on one side is sent to the primary header 16 via a bypass pipe 19, and furthermore, the cold / hot water secondary pump 14 passes through the secondary header 17 and a water pipe 20 to the air conditioner 13. To be pumped. The cold or hot water sent to the air conditioner 13 exchanges heat with the air conditioner 13 and then returns to the heat exchanger 33 again. At this time, unlike the case where the cold / hot water generator 11 and the cold / hot water primary pump 12 are operated as the heat source side device and the heat source side cold / hot water transfer device, the flow from the return water pipe 21 to the outgoing primary header 16 always flows through the bypass pipe 19. It is formed. That is, the bypass pipe 19 functions as a part of the water pipe.

Reference numeral 26 denotes a heat source control device for optimally controlling the cold / hot water generator 11, the cold / hot water primary pump 12, the cold / hot water secondary pump 14, and the radiating pump 35 in accordance with the change in the load condition of the air conditioner 13. The heat source control device 26 includes a load measuring unit 27 that measures a current load state, a bypass pipe flow measuring unit 28 that measures a current bypass pipe flow rate, and operation of the cold / hot water generator 11 and the cold / hot water secondary pump 14. A unit number / variable flow rate control calculation unit 29 for calculating the number of units and control signals for the chilled / hot water primary pump 12 and the chilled / hot water secondary pump 14, a chilled / hot water generator 11 when the load state is low, and a chilled / hot water primary pump 12, a low-load control calculation unit 32 that calculates control signals for the cold / hot water secondary pump 14 and the radiation pump 35, and a cold / hot water generator 1
1, a control output unit 3 for outputting control signals to the cold / hot water primary pump 12, the cold / hot water secondary pump 14, and the radiation pump 35.
0 is implemented. If necessary, the heat source control device 26 may be provided with a load prediction unit 31 that predicts a future change in the load state.

The load measuring section 27 and the load estimating section 31 detect current and future load states by using the load calorie and the water supply pressure as indices indicating the load state. The detected load state is input to the unit number control / variable flow rate control calculation section 29 and the low load control calculation section 32 together with the bypass pipe flow rate value measured by the bypass pipe flow rate measurement section 28.
The number-of-units control / variable flow rate control calculation unit 29 determines the appropriate number of operating chilled / hot water generators 11 and chilled / hot water secondary pumps 14 based on the load information, and also sets the chilled / hot water primary pump 12 and the chilled / hot water secondary pumps. Determine 14 appropriate variable flow control outputs. The low-load control calculation unit 32 selects whether to supply cold / hot water by the cold / hot water generator 11 and the cold / hot water primary pump 12 or to supply cold / hot water by the heat storage tank 34 and the radiation pump 35 based on the load information. At the same time, an appropriate number of operating cold / hot water secondary pumps 14 and appropriate variable flow control outputs of the cold / hot water secondary pump 14 and the radiation pump 35 are determined. The latest operation information determined by the number control / variable flow control calculation unit 29 or the low load control calculation unit 32 is output to the control output unit 30, and the control output unit 30 outputs the cold / hot water generator 11, the cold / hot water primary pump 12, An appropriate control signal for the cold / hot water secondary pump 14 and the radiation pump 35 is output to the pump variable flow control device 15.

The control of the number of cooling and heating systems is performed as shown in the flowchart of FIG. That is, for example, when the index indicating the load state is the load calorific value, the load measuring unit 27 of the heat source control device 26 uses the water supply temperature sensor 22,
Using the return water temperature sensor 23 and the flow meter 24, the operating state of the cooling and heating system is acquired using the water supply temperature, the return water temperature, and the load flow rate, and the current load heat quantity (load heat quantity = load flow rate x return water temperature difference). ) And, if necessary, the load predictor 31 performs a linear regression on the load calorie from the present time to a time before the specified time (regression range), and based on the linear regression, calculates a heat amount after the specified time from the present time (the prediction target). Predict the heat load. If the low load control is not being performed and the low load control is not possible, each increase / decrease stage request that defines the correspondence relationship between the measured load heat amount or the predicted load heat amount and the number of operating chilled / hot water generators is provided. The number of operating chilled / hot water generators 11 corresponding to the load condition is determined by collating the judgment formulas. When the determined operating number is different from the current operating number in comparison with the current operating number, the heat source control device 26 controls the chilled / hot water generator 11 through the number control / variable flow rate control calculation unit 29 and the control output unit 30. Perform step-up or step-down. In addition, the number control / variable flow control calculation unit 29 calculates the number of operating cold / hot water secondary pumps 14 according to the load state in the same manner as in the case of the cold / hot water generator 11, and outputs the cold / hot water through the control output unit 30. The control of the secondary pump 14 is performed. On the other hand, when the low load control is being performed or the low load control is possible, the low load control calculation unit 32 of the heat source control device 26 is a heat storage tank that is the second heat source side device and the heat source side cold / hot water transfer device. The low-load control is performed by operating the cooling / heating system so as to supply cold / hot water to the heat exchanger 33 by the heat pump 34 and the heat radiation pump 35.

The variable flow rate control of the cooling and heating system
The process is performed in the variable flow rate control calculation unit 29 as shown in the flowchart of FIG. That is, the cold and hot water primary pump 1
When performing the variable flow control calculation of 2, the bypass pipe flow rate is measured using the measurement value of the flow meter 25, and the preset bypass pipe flow rate target value is obtained, and the pump operation by the PID control based on the target value is obtained. After calculating the amount and checking the upper and lower limits, the pump operation amount is determined.
In this calculation process, the control output of the cold / hot water primary pump 12 is normally calculated so that the bypass pipe flow rate becomes zero. In addition, when performing the variable flow control calculation of the cold / hot water secondary pump 14, the water supply pressure is measured using the measurement value of the pressure sensor 10, and a preset water supply pressure target value is obtained, and based on this target value. After calculating the pump operation amount by PID control and checking the upper and lower limits thereof, the pump operation amount is determined. In this calculation process, for example, the control output of the cold / hot water secondary pump 14 is calculated so that the water supply pressure becomes a value determined according to the change in the load state. Further, when performing the variable flow rate control calculation of the heat radiation pump 35, the water supply temperature is measured using the measurement value of the water supply temperature sensor 22, and a preset water supply temperature target value is obtained, and the PID control based on this target value is performed. After the calculation of the pump operation amount and the upper / lower limit check are performed, the pump operation amount is determined. In this calculation process, for example, the control output of the heat radiation pump 35 is calculated so that the water supply temperature is 7 ° C. Then, based on these calculated control outputs, the cold / hot water primary pump 12, the cold / hot water secondary pump 14, and the heat radiation pump 3 are transmitted through the control output unit 30 and the pump variable flow control device 15.
5 variable flow control is performed.

The low load control of the cooling and heating system is performed as shown in the flowchart of FIG. That is, when low-load control is being performed and low-load control is possible, FIG.
As shown in the central part of FIG. If low-load control is being performed and low-load control is not possible, the cold / hot water generator 11 and the auxiliary equipment (the cold / hot water primary pump 12, the cooling water pump) are started, and the radiation pump 35 is stopped. If the low-load control is possible without performing the low-load control, the cold / hot water generator 11 and the auxiliary equipment (the cold / hot water primary pump 12, the cooling water pump) are stopped,
The radiation pump 35 is started. Here, whether or not the low load control can be performed can be determined based on whether the measured load heat amount or the predicted load heat amount is lower than a predetermined lower limit. The lower limit value may be set based on the amount of heat produced at the minimum allowable flow rate for one cold / hot water generator. For example, if the permissible minimum flow rate during operation of the chilled / hot water generator 11 is 60% of the flow rate during rated operation, a value of 60% of the production heat during rated operation is adopted as the lower limit.

FIG. 5 is a structural explanatory view showing a cooling and heating system according to a second embodiment of the present invention. In the drawings, the same portions are denoted by the same reference numerals and description thereof will be omitted. In FIG. 5, FIG.
1, a heat pump 36 is provided in place of the heat storage tank 34 in FIG. 1, a circulation pump 37 is provided in place of the heat radiation pump 35 in FIG. 1, and the heat exchanger 38 is connected to a part of the return pipe 21 Valves 401 and 40 provided on the side sub-pipe 39 to switch the flow path to the return water pipe 21 or the load-side sub-pipe 39
2,403 are provided. That is, in the present embodiment, the first heat source side device and the heat source side cold / hot water transport device are the cold / hot water generator 11 and the cold / hot water primary pump 12, and the second heat source side device and the heat source side cold / hot water transport device are A heat pump 36 and a circulation pump 37; Among these devices, when the cooling / heating load is not low, the valve 401,
Close the valve 403 and open the valve 402 to open the cold / hot water generator 11.
When the cooling / heating water primary pump 12 operates and the cooling / heating load is low, the valves 401 and 403 are opened, the valve 402 is closed, and the heat pump 36 and the circulation pump 37 are closed.
Works.

The operation of the cooling and heating system when operating the heat pump 36 and the circulation pump 37 which are the second heat source side device and the heat source side cold / hot water transfer device is as follows. That is, the cold water or hot water produced by the heat pump 36 is sent to the heat exchanger 38 by the circulation pump 37 and exchanges heat with the cold water or hot water flowing through the load side sub-pipe 39. Load side sub pipe 39 via heat exchanger 38
The cold or hot water produced on the side is sent to the outgoing primary header 16 via the bypass pipe 19 and further to the air conditioner 13 via the outgoing secondary header 17 and the water pipe 20 by the cold / hot water secondary pump 14. Pumped. The cold or hot water sent to the air conditioner 13 exchanges heat with the air conditioner 13 and then returns to the heat exchanger 38 again. At this time, unlike the case where the cold / hot water generator 11 and the cold / hot water primary pump 12 are operated as the heat source side device and the heat source side cold / hot water transfer device, the flow from the return water pipe 21 to the outgoing primary header 16 always flows through the bypass pipe 19. It is formed. That is, the bypass pipe 19 functions as a part of the water pipe.

Reference numeral 26 denotes a heat source control device for optimally controlling the cold / hot water generator 11, the cold / hot water primary pump 12, the cold / hot water secondary pump 14, and the circulation pump 37 in accordance with the change in the load condition of the air conditioner 13. The heat source control device 26 includes a load measuring unit 27 that measures a current load state, a bypass pipe flow measuring unit 28 that measures a current bypass pipe flow rate, and operation of the cold / hot water generator 11 and the cold / hot water secondary pump 14. A unit number / variable flow rate control calculation unit 29 for calculating the number of units and control signals for the chilled / hot water primary pump 12 and the chilled / hot water secondary pump 14, a chilled / hot water generator 11 when the load state is low, and a chilled / hot water primary pump 12, a low-load control calculation unit 32 that calculates control signals for the cold / hot water secondary pump 14 and the circulation pump 37, and a cold / hot water generator 1
1, a control output unit 3 for outputting control signals to the cold / hot water primary pump 12, the cold / hot water secondary pump 14, and the circulation pump 37.
0 is implemented. If necessary, the heat source control device 26 may be provided with a load prediction unit 31 that predicts a future change in the load state.

The load measuring section 27 and the load estimating section 31 detect the present and future load states by using the load calorie and the water supply pressure as indices indicating the load states. The detected load state is input to the unit number control / variable flow rate control calculation section 29 and the low load control calculation section 32 together with the bypass pipe flow rate value measured by the bypass pipe flow rate measurement section 28.
The number-of-units control / variable flow rate control calculation unit 29 determines the appropriate number of operating chilled / hot water generators 11 and chilled / hot water secondary pumps 14 based on the load information, and also sets the chilled / hot water primary pump 12 and the chilled / hot water secondary pumps. Determine 14 appropriate variable flow control outputs. Based on the load information, the low load control calculation unit 32 selects whether to supply cold / hot water by the cold / hot water generator 11 and the cold / hot water primary pump 12, or to supply cold / hot water by the heat pump 36 and the circulation pump 37. The appropriate number of operating cold / hot water secondary pumps 14,
An appropriate variable flow control output of the cold / hot water secondary pump 14 and the circulation pump 37 is determined, respectively. The latest operation information determined by the number control / variable flow control calculation unit 29 or the low load control calculation unit 32 is output to the control output unit 30, and the control output unit 30 outputs the cold / hot water generator 11, the cold / hot water primary pump 1
2. Output an appropriate control signal for the cold / hot water secondary pump 14 and the circulation pump 37 to the pump variable flow control device 15.

FIG. 6 is an explanatory diagram showing the structure of a cooling and heating system according to a third embodiment of the present invention. In the drawings, the same portions are denoted by the same reference numerals and description thereof will be omitted. In FIG. 6, FIG.
1, the cooling tower 41 of the cold / hot water generator 11 is used as a heat source instead of the heat storage tank 34 of FIG. 1, a cooling water pump 42 is used instead of the heat radiation pump 35 of FIG. 1, and the heat exchanger 43 is connected to a return pipe. 21 is provided in the load side sub-pipe 44 arranged in parallel with a part of
Valves 461, 462, 463 for switching the flow path to the return water pipe 21 or the load side sub-pipe 44, and valves 4 for switching the flow path to the cooling tower side sub-pipe 45 or the cooling water pipe 47
64, 465, 466, 467 are provided, respectively. That is, in the present embodiment, the first heat source side device and the heat source side cold / hot water transport device are the cold / hot water generator 11 and the cold / hot water primary pump 12, and the second heat source side device and the heat source side cold / hot water transport device are A cooling tower 41 and a cooling water pump 42; When the cooling load is not low among these devices, the valves 462, 463, 464, 465 are closed, the valves 461, 466, 467 are opened, and the flow path of the cooling water is switched to the cold / hot water generator 11 side. When the water generator 11 and the cold / hot water primary pump 12 are operated and the cooling load is low, the valves 462, 463, 464, 465 are opened, and the valves 461, 466, 467 are closed to heat the cooling water flow path. Switching to the exchanger 43 side, the cooling tower 41, the cooling water pump 42, and the heat exchanger 43 operate.

The operation of the cooling and heating system when operating the cooling tower 41 and the cooling water pump 42 as the second heat source side device and the heat source side cold / hot water transport device is as follows. That is, the cold water generated by the cooling tower 41 is sent to the heat exchanger 43 by the cooling water pump 42 and exchanges heat with the cold water flowing through the load side sub-pipe 44. Cold water produced on the load side sub-pipe 44 side via the heat exchanger 43 is supplied to the bypass pipe 1
9, the air is sent to the outgoing primary header 16, and further sent to the air conditioner 13 by the cold / hot water secondary pump 14 via the outgoing secondary header 17 and the water pipe 20. The cold water sent to the air conditioner 13 exchanges heat with the air conditioner 13 and then returns to the heat exchanger 43 again. At this time, unlike the case where the cold / hot water generator 11 and the cold / hot water primary pump 12 are operated as the heat source side device and the heat source side cold / hot water transfer device, the flow from the return water pipe 21 to the outgoing primary header 16 always flows through the bypass pipe 19. It is formed. That is, the bypass pipe 19 functions as a part of the water pipe.

Reference numeral 26 denotes a heat source control device for optimally controlling the chilled / hot water generator 11, the chilled / hot water primary pump 12, the chilled / hot water secondary pump 14, and the cooling water pump 42 in accordance with a change in the load condition of the air conditioner 13. . The heat source control device 26 includes a load measuring unit 27 that measures a current load state, a bypass pipe flow measuring unit 28 that measures a current bypass pipe flow rate, and operation of the cold / hot water generator 11 and the cold / hot water secondary pump 14. A unit number / variable flow rate control calculation unit 29 for calculating the number of units and control signals for the chilled / hot water primary pump 12 and the chilled / hot water secondary pump 14, a chilled / hot water generator 11 when the load state is low, and a chilled / hot water primary pump 12, a low-load control calculating unit 32 for calculating control signals for the cold / hot water secondary pump 14, the cooling water pump 42, the cold / hot water generator 11, the cold / hot water primary pump 12, and the cold / hot water secondary pump 14.
And a control output unit 30 that outputs a control signal to the cooling water pump 42. If necessary, heat source control device 2
6 may be provided with a load prediction unit 31 for predicting a change in the load state in the future.

The load measuring unit 27 and the load estimating unit 31 detect the present and future load conditions by using the load calorie and the water supply pressure as indices indicating the load conditions. The detected load state is input to the unit number control / variable flow rate control calculation section 29 and the low load control calculation section 32 together with the bypass pipe flow rate value measured by the bypass pipe flow rate measurement section 28.
The number-of-units control / variable flow rate control calculation unit 29 determines the appropriate number of operating chilled / hot water generators 11 and chilled / hot water secondary pumps 14 based on the load information, and also sets the chilled / hot water primary pump 12 and the chilled / hot water secondary pumps. Determine 14 appropriate variable flow control outputs. The low load control calculation unit 32 selects whether to supply cold / hot water by the cold / hot water generator 11 and the cold / hot water primary pump 12 or to supply cold water by the cooling tower 41 and the cooling water pump 42 based on the load information. At the same time, an appropriate number of operating cold / hot water secondary pumps 14 and appropriate variable flow control outputs of the cold / hot water secondary pump 14 and the cooling water pump 42 are determined. The latest operation information determined by the number control / variable flow control calculation unit 29 or the low load control calculation unit 32 is output to the control output unit 30, and the control output unit 30 outputs the cold / hot water generator 11, the cold / hot water primary pump 12,
An appropriate control signal for the cold / hot water secondary pump 14 and the cooling water pump 42 is output to the pump variable flow control device 15.

The cooling and heating system according to the present invention is used not only for low-load applications but also for cooling and heating
It can also be used as a peak load application when it cannot be covered by only the cold water or hot water produced by the method of FIG. In general, when a new heat source-side device is added to handle peak loads, there is a problem that the operation rate decreases in addition to the economic burden of the addition and the effect on the existing control system. Efficient operation of load handling and peak load handling eliminates these problems. FIG. 7 and FIG. 8 are flowcharts for explaining another number control operation and a peak load control operation of the cooling and heating system according to the first embodiment of the present invention. In this case, the configuration of the cooling and heating system that can be operated as a peak load compatible application is configured by replacing the low load control calculation unit 32 of FIG. 1 with a peak load control calculation unit.

The control of the number of cooling and heating systems is performed as shown in the flowchart of FIG. That is, for example, when the index indicating the load state is the load calorific value, the load measuring unit 27 of the heat source control device 26 uses the water supply temperature sensor 22,
Using the return water temperature sensor 23 and the flow meter 24, the operating state of the cooling and heating system is acquired using the water supply temperature, the return water temperature, and the load flow rate, and the current load heat quantity (load heat quantity = load flow rate x return water temperature difference). ) And, if necessary, the load predictor 31 performs a linear regression on the load calorie from the present time to a time before the specified time (regression range), and based on the linear regression, calculates a heat amount after the specified time from the present time (the prediction target). Predict the heat load. If the peak load control is not being performed and the peak load control is not required, each increase / decrease stage request that defines the correspondence between the measured load heat amount or the predicted load heat amount and the number of operating chilled / hot water generators is provided. By collating the judgment formula,
The number of operating cold / hot water generators 11 corresponding to the load state is determined. When the determined operating number is different from the current operating number in comparison with the current operating number, the heat source control device 26 controls the chilled / hot water generator 11 through the number control / variable flow rate control calculation unit 29 and the control output unit 30. Perform step-up or step-down. In addition, the number control / variable flow control calculation unit 29 calculates the number of operating cold / hot water secondary pumps 14 according to the load state in the same manner as in the case of the cold / hot water generator 11, and outputs the cold / hot water through the control output unit 30. The control of the secondary pump 14 is performed. On the other hand, when the peak load control is being performed or the peak load control is necessary, the heat source control device 26 controls all the chilled / hot water generators 11 and the chilled / hot water primary pump 12 And a peak load control operation unit provided in place of the low load control operation unit 32 operates the cooling / heating system so as to supply cold / hot water to the heat exchanger 33 by the heat storage tank 34 and the radiating pump 35 to control peak load. Is carried out.

The peak load control of the cooling and heating system is performed as shown in the flowchart of FIG. That is, when the peak load control is being performed and the peak load control is necessary, the variable flow control of the heat radiation pump 35 is performed as shown in the center of FIG. When the peak load control is being performed and the peak load control is not necessary, the chilled / hot water generator 11 and the auxiliary equipment (the chilled / hot water primary pump 12, the cooling water pump) are started, and the radiation pump 35 is stopped. When the peak load control is not being performed and the peak load control is necessary, the operation of the cold / hot water generator 11 and the auxiliary devices (the cold / hot water primary pump 12, the cooling water pump) is continued, and the radiation pump 35 is turned off. The peak load control for starting up and operating the cooling / heating system for supplying cold / hot water to the heat exchanger 33 by the heat storage tank 34 and the radiation pump 35 is performed. Here, whether or not to perform the peak load control can be determined based on whether or not the measured load heat amount or the predicted load heat amount exceeds a predetermined upper limit. This upper limit value may be set, for example, based on the amount of heat generated during rated operation for all the chilled / hot water generators, or from two chilled / hot water generators to be operated with an increase in the cooling / heating load. When it is necessary to increase the number of stages to three, the cold and hot water generator 2 is used for the purpose of preventing the third cold and hot water generator from starting immediately.
It may be set based on the amount of heat produced during rated operation for each vehicle.

The embodiment of the cooling and heating system is not limited to the embodiment described above. For example, a heat exchanger and a load side sub-pipe may be provided on the water supply pipe 20 side. Alternatively, a boiler or a cogeneration system may be provided as a heat source side device, and a heat source that supplies only hot water may be used. Further, both the low load control calculation unit 32 and the peak load control calculation unit are mounted on the heat source control device 26,
Both the low load response and the peak load response may be implemented.

[0039]

As described above, according to the present invention, by providing two sets of heat source side devices and heat source side transfer devices, the minimum flow restriction of the heat source side device due to the low load and the peak load It is possible to supply a cooling and heating system that is optimal for heating and cooling in accordance with changes in the load state of the building without being bound by the low operation rate problem caused by the air conditioner. be able to.

[Brief description of the drawings]

FIG. 1 is a configuration explanatory view showing a cooling and heating system according to a first embodiment of the present invention.

FIG. 2 is a flowchart illustrating a number control operation of the cooling and heating system according to the first embodiment of the present invention.

FIG. 3 is a flowchart illustrating a variable flow control operation of the cooling and heating system according to the first embodiment of the present invention.

FIG. 4 is a flowchart illustrating a low-load control operation of the cooling and heating system according to the first embodiment of the present invention.

FIG. 5 is a configuration explanatory view showing a cooling and heating system according to a second embodiment of the present invention.

FIG. 6 is a configuration explanatory view showing a cooling and heating system according to a third embodiment of the present invention.

FIG. 7 is a flowchart illustrating an operation of controlling the number of cooling / heating systems according to a fourth embodiment of the present invention.

FIG. 8 is a flowchart illustrating a peak load control operation of a cooling and heating system according to a fourth embodiment of the present invention.

FIG. 9 is a configuration explanatory view showing a conventional cooling and heating system.

FIG. 10 is a flowchart illustrating a number control operation of the conventional cooling and heating system.

FIG. 11 is a flowchart illustrating a variable flow control operation of the conventional cooling and heating system.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 11 Cold and hot water generator 12 Cold and hot water primary pump 13 Air conditioner 14 Cold and hot water secondary pump 15 Pump variable flow control device 16 Outgoing primary header 17 Outgoing secondary header 18 Return header 19 Bypass pipe 20 Water pipe 21 Return water pipe 22 Water temperature sensor 23 Return water temperature sensor 24 Flow meter 25 Flow meter 26 Heat source control device 27 Load measurement unit 28 Bypass pipe flow measurement unit 29 Number control / variable flow control calculation unit 30 Control output unit 31 Load prediction unit 32 Low load control calculation unit 33 Heat Exchanger 34 Thermal storage tank 35 Radiation pump

Claims (6)

[Claims] 1. A cooling and heating system for cooling and heating a building by circulating and supplying cold and hot water, comprising: a load-side device and a load-side cold and hot water transfer device for processing a cooling and heating load; A first heat source-side device and a heat source-side cold / hot water transport device for supplying cold / hot water to the device, a bypass pipe connecting the water supply side line and the return side line, and a load side water supply side line or return side A second heat source-side device and a heat source-side cold / hot water transfer device for supplying cold / hot water to the load-side device and the load-side cold / hot water transfer device via a heat exchanger provided in a pipeline; A heat source control device that performs control so as to cause the heat source control device to detect at least the cooling / heating load and the bypass pipe flow rate, and control output to the first heat source side device and the heat source side cold / hot water transport device. A first control output calculating section for calculating, and a second control output for calculating at least the cooling / heating load and the load side water supply temperature and calculating a control output for the second heat source side device and the heat source side cold / hot water transport device. A cooling and heating system, comprising: a calculation unit; and a control output unit that outputs a control output from the first control output calculation unit or the second control output calculation unit as an actual control signal. 2. A cooling and heating system for cooling and heating a building by circulating and supplying cold and hot water, comprising: a load-side device and a load-side cold and hot water transport device for processing a cooling and heating load; and the load-side device and a load-side cold and hot water transport. A first heat source-side device and a heat source-side cold / hot water transport device for supplying cold / hot water to the device, a bypass pipe connecting the water supply side line and the return side line, and a load side water supply side line or return side A load-side sub-pipe provided in parallel with a part of the pipeline, a switching means for switching a load-side cold / hot water flow path to the load-side sub-pipe, and a heat exchanger provided in the load-side sub-pipe. A second heat source-side device and a heat source-side cold / hot water transport device for supplying cold / hot water to the load-side device and the load-side cold / hot water transport device, and a heat source control device for performing control so as to circulate and supply the cold / hot water. The heat source control device A first control output calculating unit that detects at least the cooling / heating load and the bypass pipe flow rate and calculates a control output for the first heat source-side device and the heat source-side cold / hot water transport device; and at least the cooling / heating load and load. A second control output calculating unit that detects a side water supply temperature and calculates a control output for the second heat source side device and the heat source side cold / hot water transport device; and the first control output calculating unit or the second control output calculating unit. A control output unit that outputs a control output from a control output calculation unit as an actual control signal. 3. The heat-source control device stops the first heat-source-side device and the heat-source-side chilled / hot water transfer device when the cooling / heating load falls below a predetermined lower limit, and controls the control output by a second control output calculation unit. Is output as an actual control signal, and cooling and heating of the building is performed by circulating and supplying cold and hot water by using the bypass pipe as a part of a water supply side pipe or a return water side pipe. 3. The cooling and heating system according to 1 or 2. 4. The heat source control device activates a second heat source side device and a heat source side cold / hot water transfer device when the cooling / heating load exceeds a predetermined upper limit value, and controls a control output by a first control output calculation unit. The cooling and heating system according to claim 1, wherein the control output by the second control output calculation unit is output as an actual control signal. 5. The cooling and heating system according to claim 1, wherein the second heat source side device and the heat source side cold / hot water transport device are a cooling tower and a cooling water pump. 6. The apparatus according to claim 1, wherein the second heat source device is a heat pump or a heat storage tank.
Or the cooling and heating system according to 4.