JP6832732B2 - Refrigeration system - Google Patents

Description

The present invention relates to a freezing system in which a secondary refrigerant is cooled or heated by a freezing device on the primary side and supplied to a load provided on the secondary side.

A refrigeration system that cools or heats heat source water (for example, water, brine, air, etc.) by a plurality of chillers installed in parallel on the primary side and supplies it to the load provided on the secondary side, particularly 2 An air conditioner in which the flow rate on the next side changes according to an increase or decrease in load has been proposed (see, for example, Patent Document 1).

The refrigeration system described in Patent Document 1 is an air conditioner having a heat source on the primary side and a load on the secondary side via a forward header and a return water header. In the air conditioner, heat source water created from a plurality of heat sources by a heat source pump is focused on an outgoing header, heat source water is supplied to each of a plurality of loads, and recirculated water from each load is focused on a return header. Piping is connected so that the reflux water is returned to the heat source. Then, a control means is provided in which a balance tube is connected between the forward header and the return header, and the temperature of the heat source water in the forward header is controlled based on the detected temperature. By detecting the temperature of the heat source water in the forward header, the load increases, and it is quickly detected that the recirculated water on the secondary side flows through the balance pipe from the return header to the forward header, and the temperature of the heat source is detected by the control means. You are performing control. A primary recirculated water temperature detecting means for detecting the temperature of the recirculated water at the inlet of the return header, a secondary recirculated water temperature detecting means for detecting the temperature of the recirculated water at the outlet of the return header, and a balance pipe for detecting the water temperature in the balance pipe. A water temperature detecting means is provided. The control means selects, if necessary, the temperature detected by the heat source water temperature detecting means, the recirculated water primary temperature detecting means, the recirculated water secondary temperature detecting means, and the water temperature detecting means in the balance pipe, and is based on the selected temperature. The temperature of the heat source is controlled and the flow rate is controlled by the heat source pump. The pipe connection structure and the arrangement of the temperature detecting means at the key points promptly detect the imbalance of the flow rate between the primary side and the secondary side due to the load fluctuation, and the control means controls the temperature of the heat source and the flow rate. Control and running.

Japanese Unexamined Patent Publication No. 2006-132918

However, in the control in the refrigeration system described above, the imbalance of the flow rate between the primary side and the secondary side due to the load fluctuation is quickly detected by the water temperature detecting means in the balance pipe that detects the water temperature in the balance pipe. Since the control is based on the temperature of the heat source water in the forward header and the return header, the control is not executed until a temperature change appears in the forward header and the return header.

In addition, since it takes time for the temperature change to appear in the forward header and the return header, the followability to the load fluctuation is poor, which causes unnecessary power consumption.

Therefore, an object of the present invention is to provide a refrigeration system capable of improving followability to load fluctuations and saving energy in order to solve the above problems.

In order to solve the above problem, the refrigerating system according to one embodiment of the present invention is provided on the primary side and is sent from one or more refrigerating devices for heating or cooling the refrigerant, and the plurality of refrigerating devices. An upstream side header that receives the incoming refrigerant, a load that is provided on the secondary side and heat-exchanges the refrigerant sent from the upstream side header, and a downstream side header that receives the heat-exchanged refrigerant in the load. One or more primary pumps that are provided corresponding to the one or more refrigeration devices and return the refrigerant in the downstream side header to the one or more refrigeration devices, and the upstream side. A bypass pipe connecting the header and the downstream header, an upstream temperature detecting means for detecting the temperature of the refrigerant after flowing into the upstream header as the upstream temperature, and a refrigerant after flowing into the downstream header. To the downstream side temperature detecting means for detecting the temperature of the above as the downstream side temperature, the bypass temperature detecting means for detecting the temperature of the refrigerant in the bypass pipe as the bypass temperature, the upstream side temperature, the downstream side temperature, and the bypass temperature. Based on this, the control means includes a control means for controlling the one or a plurality of primary side pumps to control the flow rate of the refrigerant on the primary side, and the control means cools the load with the cooled refrigerant. in the case, the case upstream temperature is lower than the bypass temperature, by the primary pump Ru increases the flow rate of refrigerant in the primary side.

According to the present invention, it is possible to provide a refrigeration system capable of improving followability to load fluctuations and saving energy.

The system diagram of the refrigeration system which concerns on embodiment of this invention is shown. The flowchart of the control process of the refrigeration system is shown.

Hereinafter, the refrigerating system 101 according to the embodiment of the present invention will be described as an example in which water is used as the secondary refrigerant (heat medium) and the water is cooled / heated, but the secondary refrigerant is limited to this. It may be one that cools / heats, for example, brine or air.

FIG. 1 shows a system diagram of the refrigeration system 101 according to the embodiment of the present invention.

In FIG. 1, the A side is the primary side and the B side is the secondary side with respect to the alternate long and short dash line. The refrigeration system 101 includes a plurality of refrigerating devices 1a to 1d (four in the present embodiment) and primary side pumps 5a to 5d on the primary side A thereof. The refrigeration system 101 has an upstream header 7, secondary pumps 6a to 6d, an intermediate header 9, a relief valve 18, a load 20, a flow control valve 17, and a downstream header on the secondary side B. 8, a bypass pipe 13, and a controller 14 are mainly provided. In the following description, when it is not necessary to distinguish each element by the alphabet following the number in the heat source machines 1a to 1c and the symbols of other configurations, the alphabet may be omitted.

A plurality of refrigerating devices 1 are provided in parallel. The primary side pump 5 is provided on the inlet side with respect to the refrigerating device 1, and controls the flow rate of the secondary refrigerant flowing through each refrigerating device 1 by continuously controlling the rotation speed.

Each refrigerating device 1 includes a compressor (not shown) for compressing the primary refrigerant, and the compressor has a configuration in which the operating capacity can be continuously controlled. Further, each refrigerating device 1 has a heat exchanger 2 for heat exchange between the primary refrigerant and the secondary refrigerant, and an inlet temperature detecting means 3 (3a) for detecting the temperature of the secondary refrigerant on the inlet side of the heat exchanger 2. ~ 3d) and outlet temperature detecting means 4 (4a to 4d) for detecting the temperature of the secondary refrigerant on the outlet side of the heat exchanger 2.

In each refrigerating device 1, the capacity (for example, the number of revolutions) of the compressor is controlled so that the temperature detected by the outlet temperature detecting means 4 becomes a predetermined constant temperature. In order to detect the flow rate of the secondary refrigerant flowing through each refrigerating device 1, the present embodiment includes a flow rate detecting means for calculating the flow rate based on the rotation speed of the primary pump 5. For example, the controller 14 has a function as a flow rate detecting means, and calculates the flow rate based on the rotation speed of the primary pump 5. The flow rate detecting means may be configured to directly measure the amount of the secondary refrigerant flowing through the pipes flowing into and out of each refrigerating device 1 with a flow meter.

The upstream header 7 receives the secondary refrigerant sent from the refrigerating device 1. The plurality of secondary pumps 6 pump the secondary refrigerant of the upstream header 7 to the load 20 via the intermediate header 9. The relief valve 18 is provided to allow the secondary refrigerant to escape to the upstream header 7 when the pressure of the intermediate header 9 rises. The load 20 exchanges heat with air to cool or heat the air. The flow rate control valve 17 is provided at the outlet portion of the load 20 in order to adjust the flow rate of the secondary refrigerant supplied to the load 20. The secondary refrigerant of the downstream header 8 is pumped to each refrigerating device 1 by each primary pump 5.

The flow rate of the secondary refrigerant flowing through the secondary side B is controlled by controlling the number of a plurality of secondary side pumps 6 or controlling the rotation speed of at least one secondary side pump 6. The control of the secondary side pump 6 and the flow rate control valve 17 on the secondary side B is controlled by a secondary side controller (not shown) provided on the secondary side.

The bypass pipe 13 connects the upstream header 7 and the downstream header 8. When the flow rate of the secondary refrigerant flowing through the secondary side B is larger than the flow rate of the secondary refrigerant flowing through the primary side A, a part of the secondary refrigerant is discharged from the downstream side header 8 to the upstream side via the bypass pipe 13. When the flow rate of the secondary refrigerant flowing to the header 7 side and conversely flowing through the primary side A is larger than the flow rate of the secondary refrigerant flowing through the secondary side B, a part of the secondary refrigerant of the upstream header 7 is bypassed. It flows to the downstream side header 8 via the pipe 13.

Further, the refrigeration system 101 includes an upstream temperature detecting means (thermistor) 10, a downstream temperature detecting means (thermistor) 11, a bypass temperature detecting means (thermistor) 12, a load inlet temperature detecting means 15, and a load outlet temperature. The detection means 16 is provided.

The load inlet temperature detecting means 15 detects the inlet temperature of the secondary refrigerant entering the load 20. The load outlet temperature detecting means 16 detects the outlet temperature of the secondary refrigerant discharged from the load 20. The secondary pump 6 is controlled according to the temperature difference of the secondary refrigerant detected by the temperature detecting means 15 and 16, and if the temperature difference is larger than the set value (predetermined temperature difference), the pump 6 is supplied to the load 20. The temperature difference is controlled so as to approach the set value by increasing the flow rate of the secondary refrigerant and decreasing the flow rate of the secondary refrigerant supplied to the load 20 if the temperature difference is smaller than the set value. The bypass temperature detecting means 12 detects the temperature of the secondary refrigerant in the bypass pipe 13.

The upstream side temperature detecting means 10 detects the temperature of the secondary refrigerant in the upstream side header 7. When the secondary refrigerant flows from the bypass pipe 13 to the upstream header 7, the upstream temperature detecting means 10 uses the secondary refrigerant flowing from each refrigerating device 1 and the secondary refrigerant flowing through the bypass pipe 13. The temperature of the secondary refrigerant mixed with the refrigerant is detected. Since the temperature detected by the upstream temperature detecting means 10 is substantially the same as the temperature detected by the load inlet temperature detecting means 15, the load inlet temperature detecting means 15 can be used instead.

The downstream temperature detecting means 11 detects the temperature of the secondary refrigerant in the downstream header 8. When the secondary refrigerant flows from the bypass pipe 13 to the downstream header 8, the downstream temperature detecting means 11 includes the secondary refrigerant flowing from the load 20 and the secondary refrigerant flowing through the bypass pipe 13. Detect the temperature of the secondary refrigerant mixed by merging. Since the temperature detected by the downstream temperature detecting means 11 is substantially the same as the temperature detected by the inlet temperature detecting means 3, the inlet temperature detecting means 3 can be used instead.

The temperature detected by the upstream side temperature detecting means 10 is the operating temperature of the plurality of refrigerating devices 1 when there is no secondary refrigerant flowing from the downstream side header 8 to the upstream side header 7 via the bypass pipe 13. It becomes the same as the average value of the temperatures detected by the outlet temperature detecting means 4 of the freezing device 1. That is, in the present embodiment, since the flow rate of the primary side pump 5 of the freezing device 1 during operation is controlled to be the same, the temperature detected by the outlet temperature detecting means 4 of the freezing device 1 during operation The average value becomes equal to the temperature of the secondary refrigerant flowing out of the freezing device 1 in operation and mixed in the upstream header 7.

When the air is cooled by the load 20, if there is a secondary refrigerant flowing from the downstream header 8 to the upstream header 7 via the bypass pipe 13, the temperature detected by the upstream temperature detecting means 10 is determined. It is higher than the average value of the temperatures detected by the outlet temperature detecting means 4 in the operating refrigerating device 1 among the plurality of refrigerating devices 1. The reason is that a part of the secondary refrigerant heated by the load 20 flows from the downstream header 8 into the upstream header 7 via the bypass pipe 13.

On the other hand, when the air is heated by the load 20, if there is a secondary refrigerant flowing from the downstream header 8 to the upstream header 7 via the bypass pipe 13, the temperature detected by the upstream temperature detecting means 10 Is lower than the average value of the temperatures detected by the outlet temperature detecting means 4 in the operating freezing device 1 among the plurality of freezing devices 1. The reason is that a part of the secondary refrigerant cooled by the load 20 flows from the downstream header 8 into the upstream header 7 via the bypass pipe 13.

The temperature detected by the downstream temperature detecting means 11 is during operation among the plurality of refrigerating devices 1 when there is no secondary refrigerant flowing from the upstream header 7 to the downstream header 8 via the bypass pipe 13. It becomes the same as the average value of the temperatures detected by the inlet temperature detecting means 3 of the freezing device 1. That is, in the present embodiment, since the flow rate of the primary pump 5 of the refrigerating device 1 during operation is controlled to be the same, the temperature detected by the inlet temperature detecting means 3 of the refrigerating device 1 during operation The average value is equal to the temperature of the secondary refrigerant in the downstream header 8.

Further, when there is no secondary refrigerant flowing from the upstream header 7 to the downstream header 8 via the bypass pipe 13, the temperature detected by the inlet temperature detecting means 3 of the refrigerating apparatus 1 is the temperature detected by the load outlet temperature detecting means 16. It is approximately equal to the detected temperature. Since the temperature on the load outlet side is controlled to be a predetermined temperature (set temperature), the temperature detected by the inlet temperature detecting means 3 is substantially equal to the predetermined temperature (set temperature).

When the air is cooled by the load 20, if there is a secondary refrigerant flowing from the upstream header 7 to the downstream header 8 via the bypass pipe 13, the temperature detected by the inlet temperature detecting means 3 is the load. The temperature becomes lower than the temperature detected by the outlet temperature detecting means 16 or a predetermined temperature (set temperature). The reason is that a part of the low temperature secondary refrigerant cooled by the refrigerating apparatus 1 flows from the upstream header 7 into the downstream header 8 via the bypass pipe 13 and is heated by the load 202. This is because it is mixed with the next refrigerant.

When the air is heated by the load 20, if there is a secondary refrigerant flowing from the upstream header 7 to the downstream header 8 via the bypass pipe 13, the temperature detected by the inlet temperature detecting means 3 is the load. The temperature becomes higher than the temperature detected by the outlet temperature detecting means 16 or a predetermined temperature (set temperature). The reason is that a part of the high temperature secondary refrigerant heated by the refrigerating apparatus 1 flows from the upstream header 7 into the downstream header 8 via the bypass pipe 13 and is cooled by the load 202. This is because it is mixed with the next refrigerant.

The temperature detected by the upstream temperature detecting means 10 and the temperature detected by the bypass temperature detecting means 12 are compared, and the temperature detected by the downstream temperature detecting means 11 and the temperature detected by the bypass temperature detecting means 12 are detected. By comparing with the temperature, it is possible to know in which direction the secondary refrigerant is flowing in the bypass pipe 13. The controller (control means) 14 controls the flow rate of the secondary refrigerant flowing on the primary side based on the flow direction of the secondary refrigerant in the bypass pipe 13.

Further, the controller 14 is 1 based on the detection values from the upstream temperature detecting means 10, the downstream temperature detecting means 11, the bypass temperature detecting means 12, the outlet temperature detecting means 4 of the refrigerating device 1, and the inlet temperature detecting means 3. The refrigerating device 1 and the primary pump 5 provided on the secondary A are controlled. The secondary side pump 6 and the flow rate control valve 17 provided on the secondary side B are controlled by a secondary side controller (not shown) as described above.

Next, the control process executed by the controller 14 in the refrigeration system 101 will be described. The program related to the control process is stored in the ROM of the controller 14, read by the CPU of the controller 14, and is always executed during the operation of the refrigeration system 101.

FIG. 2 shows a flowchart of the control process of the refrigeration system 101.

The controller 14 acquires the preset inlet temperature of the load 20: Ta, outlet temperature Tb, maximum flow rate Umax of the primary pump 5, minimum flow rate Umin, control constants V, and W (S101).

The controller 14 sets the inlet water temperatures Ti _{1 to} Ti ₄ by the inlet temperature detecting means 3, the outlet water temperatures To _{1 to} To ₄ by the outlet temperature detecting means, and the upstream water temperature (upstream temperature) Ts from the upstream temperature detecting means 10. , The water temperature (downstream temperature) Tr downstream from the downstream temperature detecting means 11 and the bypass water temperature (bypass temperature) Tx by the bypass temperature detecting means 12 of the secondary refrigerant flowing by the operating primary pump 5. The primary side flow rate U, which is the flow rate, is detected (S102).

When the load 20 is cooled, the controller 14 determines whether or not the value obtained by subtracting the control constant V from the bypass water temperature Tx is larger than the upstream water temperature Ts (S103). That is, it is determined whether or not the condition of Tx−V> Ts is satisfied. Here, the control constant V is a value set in consideration of the variation in the water temperature, and depending on the magnitude of the value, it is possible to make it easier or slower to enter the later control (S104 to S106). For example, when the load 20 is cooled and the secondary refrigerant flows from the downstream header 8 to the upstream header 7, the secondary refrigerant in the downstream header 8 is better than the secondary refrigerant in the upstream header 7. If the bypass water temperature Tx and the upstream water temperature Ts are simply compared, the condition of Tx> Ts is easily satisfied, and the flow rate increase control in steps S104 to S106 is executed. .. In order to prevent the transition to the flow rate increase control immediately in this way, by subtracting the control constant V from the bypass water temperature Tx, the flow rate must increase to some extent from the downstream header 8 to the upstream header 7. It is possible to prevent the transition to increase control.

When the value obtained by subtracting the control constant V from the bypass water temperature Tx is larger than the upstream water temperature Ts (S103: YES), is the detected primary flow rate U equal to the maximum flow rate Umax of the primary pump 5? Whether or not it is determined (S104). When the primary flow rate U is equal to the maximum flow rate Umax of the primary pump 5 (S104: YES), the controller 14 increases the number of operating units of the primary pump 5 and the refrigerating device 1 (S105). That is, the stopped primary pump 5 and the refrigerating device 1 are operated. When the primary flow rate U is not equal to the maximum flow rate Umax of the primary pump 5 (S104: NO), that is, when the primary flow rate U is less than the maximum flow rate Umax of the primary pump 5, the controller 14 operates. The flow rate of the primary pump 5 inside is increased (S106). After step S105 or step S106, the controller 14 determines whether or not the time waiting for the effect has elapsed (S112), returns to step S102 after the time has elapsed, and repeats the processes of steps S102 to S112.

When the load 20 is being cooled, the temperature of the downstream header 8 becomes higher than that of the upstream header 7. When the flow rate of the secondary refrigerant flowing through the secondary side B is larger than the flow rate of the secondary refrigerant flowing through the primary side A, a part of the secondary refrigerant is discharged from the downstream side header 8 to the upstream side via the bypass pipe 13. It flows to the header 7. Therefore, the bypass water temperature Tx becomes larger than the upstream water temperature Ts. The flow rate of the primary side A is increased by increasing the number of operating units of the primary side pump 5 or increasing the flow rate of the primary side pump 5.

When the load 20 is cooled and the value obtained by subtracting the control constant V from the bypass water temperature Tx is equal to or less than the upstream water temperature Ts (S103: NO), the controller 14 adds the control constant W to the bypass water temperature Tx. It is determined whether or not the value is smaller than the downstream water temperature Tr (S107). That is, it is determined whether or not the condition of Tx + W <Tr is satisfied. Here, the control constant W is a value set in consideration of the variation in the water temperature, and depending on the magnitude of the value, it is possible to make it easier or slower to enter the later control (S108 to S110). For example, when the load 20 is cooled and the secondary refrigerant flows from the upstream header 7 to the downstream header 8, the secondary refrigerant in the upstream header 7 is the secondary refrigerant in the downstream header 8. Since the temperature is lower than that, if the bypass water temperature Tx and the downstream water temperature Tr are simply compared, the condition of Tx <Tr is easily satisfied, and the flow rate reduction control in steps S108 to S110 is executed. Become. By adding the control constant W to the bypass water temperature Tx in order to prevent the flow rate reduction control from immediately shifting to the flow rate reduction control, the flow rate must be increased to some extent from the upstream header 7 to the downstream header 8. It is possible to prevent the transition to increase control.

When the value obtained by adding the control constant W to the bypass water temperature Tx is smaller than the downstream water temperature Tr (S107: YES), is the detected primary flow rate U equal to the minimum flow rate Umin of the primary pump 5? Whether or not it is determined (S108). When the primary flow rate U is equal to the minimum flow rate Umin of the primary pump 5 (S108: YES), the controller 14 stops a part of the operating primary pump 5 and the refrigerating device 1 to reduce the number of operating units. The stage is reduced (S109). When the primary flow rate U is not equal to the minimum flow rate Umin of the primary pump 5 (S108: NO), that is, when the primary flow rate U is greater than the minimum flow rate Umin of the primary pump 5, the controller 14 operates. The flow rate of the primary pump 5 inside is reduced (S110). After that, the controller 14 determines whether or not the effect waiting time has elapsed (S112), returns to step S102 after the time has elapsed, and repeats the processes of steps S102 to 112.

When the load 20 is being cooled, the temperature of the downstream header 8 becomes higher than that of the upstream header 7. When the flow rate of the secondary refrigerant flowing through the primary side A is larger than the flow rate of the secondary refrigerant flowing through the secondary side B, a part of the secondary refrigerant is discharged from the upstream header 7 to the downstream side via the bypass pipe 13. It flows to the header 8. Therefore, the bypass water temperature Tx is lower than the downstream water temperature Tr. The flow rate of the primary side A is reduced by reducing the number of operating units of the primary side pump 5 or reducing the flow rate of the primary side pump 5.

When the value obtained by adding the control constant W to the bypass water temperature Tx is smaller than the downstream water temperature Tr (S107: YES), the controller 14 holds the current flow rate of the primary pump 5 (S111). After that, the controller 14 determines whether or not the effect waiting time has elapsed (S112), returns to step S102 after the time has elapsed, and repeats the processes of steps S102 to 112.

On the other hand, in step S103, when the load 20 is being heated, the controller 14 determines whether or not the value obtained by adding the control constant V to the bypass water temperature Tx is smaller than the upstream water temperature Ts (S103). That is, it is determined whether or not the condition of Tx + V <Ts is satisfied. Similar to the above, the control constant V is a value set in consideration of the variation in the water temperature, and depending on the magnitude of the value, it is easy or slow to enter the later control (S104 to S106). For example, when the load 20 is heated and the secondary refrigerant flows from the downstream header 8 to the upstream header 7, the secondary refrigerant in the downstream header 8 is the secondary refrigerant in the upstream header 7. Since the temperature is lower than that, if the bypass water temperature Tx and the upstream water temperature Ts are simply compared, the condition Tx <Ts is easily satisfied, and the flow rate increase control in steps S104 to S106 is executed. Become. In order to prevent the transition to the flow rate increase control immediately in this way, by adding the control constant V to the bypass water temperature Tx, the flow rate must be increased to some extent from the downstream header 8 to the upstream header 7. It is possible to prevent the transition to increase control.

When the load 20 is being heated and the value obtained by subtracting the control constant V from the bypass water temperature Tx is equal to or less than the upstream water temperature Ts (S103: NO), the controller 14 subtracts the control constant W from the bypass water temperature Tx. It is determined whether or not the value is smaller than the downstream water temperature Tr (S107). That is, it is determined whether or not the condition of Tx−W> Tr is satisfied. Similar to the above, the control constant W is a value set in consideration of the variation in water temperature, and depending on the magnitude of the value, it is easy or slow to enter the later control (S108 to S110). For example, when the load 20 is heated and the secondary refrigerant flows from the upstream header 7 to the downstream header 8, the secondary refrigerant in the upstream header 7 is the secondary refrigerant in the downstream header 8. Since the temperature is higher than that, if the bypass water temperature Tx and the downstream water temperature Tr are simply compared, the condition Tx> Tr is easily satisfied, and the flow rate reduction control in steps S108 to S110 is executed. Become. In order to prevent the transition to the flow rate reduction control immediately in this way, by subtracting the control constant W from the bypass water temperature Tx, the flow rate unless the flow rate of the secondary refrigerant increases to some extent from the upstream header 7 to the downstream header 8. It is possible to prevent the transition to increase control.

As described above, in the refrigeration system 101 according to the present embodiment, the controller 14 controls a plurality of primary side pumps 5 based on the upstream side water temperature Ts, the downstream side water temperature Tr, and the bypass water temperature Tx. The flow rate of the secondary refrigerant on the next side A is controlled.

According to this configuration, the bypass water temperature Tx, which immediately changes with respect to the fluctuation of the flow rate on the load 20 side, is detected and compared with the upstream water temperature Ts and the downstream water temperature Tr, so that the flow rate on the load 20 side Fluctuations can be detected at an early stage, and the flow rate of the secondary refrigerant on the primary side A can be controlled by controlling the primary side pump 5 based on the detection result. Therefore, it is possible to improve the followability to the load fluctuation, reduce the power of the primary pump 5, and save energy in the refrigeration system 101.

Further, when the load 20 is cooled by the cooled refrigerant, when the upstream water temperature Ts is lower than the bypass water temperature Tx, the controller 14 increases the flow rate of the refrigerant on the primary side A by the primary pump 5 to heat the load 20. When the load 20 is heated by the refrigerant, if the upstream water temperature Ts is higher than the bypass water temperature Tx, the primary pump 5 increases the flow rate of the refrigerant on the primary side A. Therefore, even when the flow rate of the secondary refrigerant flowing through the secondary side B is larger than the flow rate of the secondary refrigerant flowing through the primary side A, the secondary side A and the secondary side B are secondary. The flow rate balance of the refrigerant can be returned to the desired state at an early stage.

Further, when the flow rate of the operating primary side pump 5 is equal to the maximum flow rate, the controller 14 operates the stopped refrigerating device 1 and the primary side pump 5 to charge the refrigerant of the primary side A. If the flow rate is increased and the flow rate of the operating primary pump 5 is less than its maximum flow rate, the flow rate of the operating primary pump 5 is increased to increase the flow rate of the refrigerant on the primary side A. Increase. In this way, since the number of operating units of the refrigerating device 1 and the primary side pump 5 is increased only when the flow rate of the primary side pump 5 during operation is the maximum flow rate, the number of operating units of the refrigerating device 1 and the primary side pump 5 is increased. It is possible to suppress the increase in the freezing system 101 and to save energy in the refrigeration system 101.

Further, when the load 20 is cooled by the cooled refrigerant, when the downstream water temperature Tr is higher than the bypass water temperature Tx, the controller 14 reduces the flow rate of the refrigerant on the primary side A by the primary pump 5 to heat the load 20. When the load 20 is heated by the refrigerant, if the downstream water temperature Tr is lower than the bypass water temperature Tx, the primary pump 5 reduces the flow rate of the refrigerant on the primary side A. Therefore, even when the flow rate of the secondary refrigerant flowing through the primary side A is larger than the flow rate of the secondary refrigerant flowing through the secondary side B, the secondary side A and the secondary side B are secondary. The flow rate balance of the refrigerant can be returned to the desired state at an early stage.

When the flow rate of the operating primary side pump 5 is equal to the minimum flow rate, the controller 14 stops a part of the operating refrigerating device 1 and the primary side pump 5 and causes the refrigerant of the primary side A to stop. If the flow rate of the primary pump 5 in operation is higher than the minimum flow rate, the flow rate of the primary pump 5 in operation is reduced to reduce the flow rate of the refrigerant in the primary side A. To reduce. In this way, when the flow rate of the operating primary side pump 5 is the minimum flow rate, a part of the operating refrigerating device 1 and the primary side pump 5 is stopped, so that the refrigerating system 101 can be energy-saving. Can be done.

The present invention is not limited to the above-described examples. A person skilled in the art can make various additions and changes within the scope of the present invention.

For example, the refrigerating system 101 in the above embodiment includes a plurality of refrigerating devices 1 and a primary side pump 5, but the refrigerating device 1 and the primary side pump 5 may be one unit. In this case, in the flowchart of the control process of FIG. 2, the number of operating units in steps S105 and S108 is not increased or decreased, but only the flow rate in steps S106 and 110 is increased or decreased. Further, the control constants V and W in steps S103 and 107 of FIG. 2 may be changed as needed, and the control constants V and W may not be used.

Further, in the above embodiment, the thermistor is used as the temperature detecting means.
Further, in the above-described embodiment, the temperature is detected by using the temperature detection thermistor, but the temperature may be detected by using another method. Further, in the above embodiment, the flow rates of the primary pumps 5 are made equal to each other, and the increase / decrease of the flow rate is also equal. However, the flow rates of the primary pumps 5 are different and the increase / decrease of the flow rate is also different. It may be configured. In this case, the same can be applied by comprehensively determining the flow rate of the primary pump 5.

Further, in the above embodiment, the temperature detected by the upstream side temperature detecting means 10 is used as the upstream side water temperature (upstream side temperature) Ts, but the temperature detected by the load inlet temperature detecting means 15 may be used. In this case, the load inlet temperature detecting means 15 corresponds to the upstream temperature detecting means. As the downstream water temperature (downstream temperature) Tr, the temperature detected by the downstream temperature detecting means 11 is used, but the temperature detected by the inlet temperature detecting means 3 may be used. In this case, the inlet temperature detecting means 3 corresponds to the downstream temperature detecting means.

1a to 1d ... Refrigerator, 2a to 2d ... Heat exchanger, 3a to 3d ... Inlet temperature detecting means, 4a to 4d ... Outlet temperature detecting means, 5a to 5d ... Primary side pump, 6a to 6d ... Secondary side pump , 7 ... upstream header, 8 ... downstream header, 10 ... upstream temperature detecting means, 11 ... downstream temperature detecting means, 12 ... bypass temperature detecting means, 13 ... bypass pipe, 14 ... controller, 20 ... load

Claims (7)

One or more refrigerating devices provided on the primary side to heat or cool the refrigerant,
An upstream header that receives the refrigerant sent from the plurality of refrigerating devices, and
A load provided on the secondary side for heat exchange of the refrigerant sent from the upstream header, and
A downstream header that receives the heat-exchanged refrigerant under the load, and
One or more primary pumps provided corresponding to the one or more refrigeration devices and returning the refrigerant in the downstream header to the one or more refrigeration devices.
A bypass pipe connecting the upstream header and the downstream header,
An upstream temperature detecting means that detects the temperature of the refrigerant after flowing into the upstream header as the upstream temperature, and
A downstream temperature detecting means that detects the temperature of the refrigerant after flowing into the downstream header as the downstream temperature, and
Bypass temperature detecting means for detecting the temperature of the refrigerant in the bypass pipe as the bypass temperature,
A control means for controlling the flow rate of the refrigerant on the primary side by controlling the one or a plurality of primary side pumps based on the upstream side temperature, the downstream side temperature, and the bypass temperature. ,
When the control means cools the load with a cooled refrigerant, the control means
A refrigeration system in which the primary side pump increases the flow rate of the primary side refrigerant when the upstream side temperature is lower than the bypass temperature. One or more refrigerating devices provided on the primary side to heat or cool the refrigerant,
An upstream header that receives the refrigerant sent from the plurality of refrigerating devices, and
A load provided on the secondary side for heat exchange of the refrigerant sent from the upstream header, and
A downstream header that receives the heat-exchanged refrigerant under the load, and
One or more primary pumps provided corresponding to the one or more refrigeration devices and returning the refrigerant in the downstream header to the one or more refrigeration devices.
A bypass pipe connecting the upstream header and the downstream header,
An upstream temperature detecting means that detects the temperature of the refrigerant after flowing into the upstream header as the upstream temperature, and
A downstream temperature detecting means that detects the temperature of the refrigerant after flowing into the downstream header as the downstream temperature, and
Bypass temperature detecting means for detecting the temperature of the refrigerant in the bypass pipe as the bypass temperature,
A control means for controlling the flow rate of the refrigerant on the primary side by controlling the one or a plurality of primary side pumps based on the upstream side temperature, the downstream side temperature, and the bypass temperature. ,
When the control means heats the load with a heated refrigerant, the control means
A refrigeration system in which the primary side pump increases the flow rate of the primary side refrigerant when the upstream side temperature is higher than the bypass temperature. One or more refrigerating devices provided on the primary side to heat or cool the refrigerant,
An upstream header that receives the refrigerant sent from the plurality of refrigerating devices, and
A load provided on the secondary side for heat exchange of the refrigerant sent from the upstream header, and
A downstream header that receives the heat-exchanged refrigerant under the load, and
One or more primary pumps provided corresponding to the one or more refrigeration devices and returning the refrigerant in the downstream header to the one or more refrigeration devices.
A bypass pipe connecting the upstream header and the downstream header,
An upstream temperature detecting means that detects the temperature of the refrigerant after flowing into the upstream header as the upstream temperature, and
A downstream temperature detecting means that detects the temperature of the refrigerant after flowing into the downstream header as the downstream temperature, and
Bypass temperature detecting means for detecting the temperature of the refrigerant in the bypass pipe as the bypass temperature,
A control means for controlling the flow rate of the refrigerant on the primary side by controlling the one or a plurality of primary side pumps based on the upstream side temperature, the downstream side temperature, and the bypass temperature. ,
When the control means cools the load with a cooled refrigerant, the control means
A refrigeration system in which the primary side pump reduces the flow rate of the primary side refrigerant when the downstream side temperature is higher than the bypass temperature. One or more refrigerating devices provided on the primary side to heat or cool the refrigerant,
An upstream header that receives the refrigerant sent from the plurality of refrigerating devices, and
A load provided on the secondary side for heat exchange of the refrigerant sent from the upstream header, and
A downstream header that receives the heat-exchanged refrigerant under the load, and
One or more primary pumps provided corresponding to the one or more refrigeration devices and returning the refrigerant in the downstream header to the one or more refrigeration devices.
A bypass pipe connecting the upstream header and the downstream header,
An upstream temperature detecting means that detects the temperature of the refrigerant after flowing into the upstream header as the upstream temperature, and
A downstream temperature detecting means that detects the temperature of the refrigerant after flowing into the downstream header as the downstream temperature, and
Bypass temperature detecting means for detecting the temperature of the refrigerant in the bypass pipe as the bypass temperature,
A control means for controlling the flow rate of the refrigerant on the primary side by controlling the one or a plurality of primary side pumps based on the upstream side temperature, the downstream side temperature, and the bypass temperature. ,
When the control means heats the load with a heated refrigerant, the control means
A refrigeration system in which the primary side pump reduces the flow rate of the primary side refrigerant when the downstream side temperature is lower than the bypass temperature. The control means
When the flow rate of the primary pump in operation is equal to the maximum flow rate, the refrigerating device and the primary pump that are stopped are operated to increase the flow rate of the refrigerant on the primary side.
A claim that when the flow rate of the primary pump in operation is less than its maximum flow rate, the flow rate of the primary pump in operation is increased to increase the flow rate of the refrigerant on the primary side. The freezing system according to 1. When the control means cools the load with a cooled refrigerant, the control means
The refrigeration system according to claim 3 , wherein when the upstream temperature is lower than the bypass temperature, the primary pump increases the flow rate of the primary refrigerant. The control means
When the flow rate of the primary pump in operation is equal to the minimum flow rate, the refrigerating apparatus in operation and a part of the primary pump are stopped to reduce the flow rate of the refrigerant on the primary side. Let me
Claims that when the flow rate of the primary pump in operation is higher than its minimum flow rate, the flow rate of the primary pump in operation is reduced to reduce the flow rate of the refrigerant on the primary side. 3 or the refrigeration system according to claim 4.

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