WO2022030103A1 - Hot water supply system - Google Patents

Abstract

A hot water supply system (1) comprises: a vapor compression heat pump circuit (10) that is configured by a compressor (11), a first heat-radiating heat exchanger (12A), a second heat-radiating heat exchanger (12B), an expansion valve (13), and a heat-absorbing heat exchanger (14) being connected in an annular shape by a refrigerant circulation line (L9), and extracts heat with the first heat-radiating heat exchanger (12A) and/or the second heat-radiating heat exchanger (12B) by driving the compressor (11); a hot water storage tank (60) for storing make-up water (W2); a water circulation line (L1) for circulating the stored water (W3) in the hot water storage tank (60) to the first heat-radiating heat exchanger (12A); a make-up water line (L2) for supplying the make-up water (W2) to the hot water storage tank (60) while circulating the make-up water (W2) to the second heat-radiating heat exchanger (12B); a refrigerant temperature adjustment means (50) for adjusting the temperature of liquid refrigerant (R) flowing into the expansion valve (13); and a control means (100) for controlling the refrigerant temperature adjustment means (50).

Description

Hot water supply system

This application claims priority based on Japanese Patent Application No. 2020-131897 filed in Japan on August 3, 2020, the contents of which are incorporated herein by reference.
The present invention relates to a hot water supply system.

As is well known, the energy efficiency of heat pump water heaters is indicated by COP (coefficient of performance). Various improvements have been made to the refrigeration cycle to increase this COP. For example, in Patent Documents 1 and 2, a supercooler is provided after the condenser of the heat pump circuit, and the stored water in the hot water storage tank is circulated and heated in the condenser, while the supercooler is used in the hot water storage tank. A hot water supply system configured to circulate and preheat make-up water is described.

Special Fair 2-27582 Gazette Jitsukaihei No. 3-3665 Gazette

In the case of a configuration in which the stored water in the hot water storage tank is circulated and heated only by the condenser, the temperature difference between the stored water and the heat source air increases as the temperature of the stored water rises, so it is difficult to maintain a high COP. be. On the other hand, in the hot water supply system described in Patent Documents 1 and 2, the heating capacity of the entire system is enhanced by preheating the low-temperature make-up water with a supercooler to increase the COP.
However, in such a hot water supply system, when the water source temperature of the make-up water is low, the liquid refrigerant flowing into the expansion valve passes through the condenser and the supercooler in order to be extremely cooled. There is. In a situation where a highly supercooled liquid refrigerant is supplied to the evaporator, moist vapor is sent to the compressor with insufficient vaporization in the evaporator. When the compressor inhales moist vapor, the compressor may be damaged by a liquid hammer or the like due to liquid compression.

The present invention has been made in view of the above problems, and is a hot water supply system capable of preventing damage to the compressor in a configuration in which a heat exchanger for heating stored water and a heat exchanger for heating make-up water are provided in a heat pump circuit. The purpose is to provide.

In the present invention, the compressor, the first heat exchanger for heat dissipation, the second heat exchanger for heat dissipation, the expansion valve and the heat exchanger for heat absorption are connected in an annular shape by a refrigerant circulation line, and the first is driven by the compressor. A steam compression type heat pump circuit that takes out heat from the heat exchanger for heat dissipation and / or the second heat exchanger for heat dissipation, a hot water storage tank that stores make-up water, and the water stored in the hot water storage tank for the first heat dissipation. Adjust the temperature of the water circulation line that circulates in the heat exchanger, the make-up water line that sends make-up water to the hot water storage tank while circulating make-up water to the second heat exchanger, and the liquid refrigerant flowing into the expansion valve. The present invention relates to a hot water supply system including a refrigerant temperature adjusting means for controlling the heat and a control means for controlling the refrigerant temperature adjusting means.

Further, the refrigerant temperature adjusting means of the hot water supply system is connected to a temperature sensor that detects the temperature of the liquid refrigerant flowing into the expansion valve and the refrigerant circulation line, and supplies the refrigerant to the second heat dissipation heat exchanger. The control means includes a first bypass line to be bypassed, a first distribution valve for adjusting the distribution amount of the refrigerant to be supplied to the second heat dissipation heat exchanger and the refrigerant to be supplied to the first bypass line. It is preferable to control the first distribution valve so that the detection temperature of the temperature sensor reaches the target temperature while the compressor is being driven.

Further, the refrigerant temperature adjusting means of the hot water supply system includes a temperature sensor that detects the temperature of the liquid refrigerant flowing into the expansion valve, a pressure sensor that detects the pressure of the liquid refrigerant flowing into the expansion valve, and the refrigerant circulation line. A first bypass line that is connected to and bypasses the refrigerant to the second heat dissipation heat exchanger, and a refrigerant that is supplied to the second heat dissipation heat exchanger and a refrigerant that is supplied to the first bypass line. A first distribution valve for adjusting the distribution amount is provided, and the control means obtains the condensation temperature of the gas refrigerant from the detection pressure of the pressure sensor while the compressor is being driven, and obtains the condensation temperature of the gas refrigerant from the condensation temperature of the temperature sensor. It is preferable to calculate the degree of overcooling of the liquid refrigerant by subtracting the detected temperature, and control the first distribution valve so that the calculated degree of overcooling becomes the target degree of overcooling.

Further, the refrigerant temperature adjusting means of the hot water supply system is connected to a temperature sensor that detects the temperature of the liquid refrigerant flowing into the expansion valve and the make-up water line, and makes up water for the second heat dissipation heat exchanger. A second bypass line for bypassing the above, and a second distribution valve for adjusting the distribution amount of the make-up water supplied to the second heat dissipation heat exchanger and the make-up water supplied to the second bypass line are provided. It is preferable that the control means controls the second distribution valve so that the detection temperature of the temperature sensor reaches the target temperature while the compressor is being driven.

Further, the refrigerant temperature adjusting means of the hot water supply system includes a temperature sensor that detects the temperature of the liquid refrigerant flowing into the expansion valve, a pressure sensor that detects the pressure of the liquid refrigerant flowing into the expansion valve, and the make-up water line. A second bypass line that is connected to the second heat dissipation heat exchanger to bypass the make-up water, and the make-up water to be supplied to the second heat dissipation heat exchanger and the second bypass line. A second distribution valve for adjusting the distribution amount of make-up water is provided, and the control means obtains the condensation temperature of the gas refrigerant from the detection pressure of the pressure sensor while the compressor is being driven, and the condensation temperature is used to obtain the condensation temperature. It is preferable to calculate the degree of supercooling of the liquid refrigerant by subtracting the detected temperature of the temperature sensor, and control the second distribution valve so that the calculated degree of supercooling becomes the target degree of supercooling.

Further, the refrigerant temperature adjusting means of the hot water supply system is connected to a temperature sensor that detects the temperature of the liquid refrigerant flowing into the expansion valve and the refrigerant circulation line, and supplies the refrigerant to the first heat dissipation heat exchanger. The control means includes a third bypass line to be bypassed, a third distribution valve for adjusting the distribution amount of the refrigerant to be supplied to the first heat dissipation heat exchanger and the refrigerant to be supplied to the third bypass line. It is preferable to control the third distribution valve so that the detection temperature of the temperature sensor reaches the target temperature while the compressor is being driven.

Further, the refrigerant temperature adjusting means of the hot water supply system includes a temperature sensor that detects the temperature of the liquid refrigerant flowing into the expansion valve, a pressure sensor that detects the pressure of the liquid refrigerant flowing into the expansion valve, and the refrigerant circulation line. A third bypass line that is connected to the first heat dissipation heat exchanger and bypasses the refrigerant, and a refrigerant that is supplied to the first heat dissipation heat exchanger and a refrigerant that is supplied to the third bypass line. A third distribution valve for adjusting the distribution amount is provided, and the control means obtains the condensation temperature of the gas refrigerant from the detection pressure of the pressure sensor while the compressor is being driven, and obtains the condensation temperature of the gas refrigerant from the condensation temperature of the temperature sensor. It is preferable to calculate the degree of overcooling of the liquid refrigerant by subtracting the detected temperature, and control the third distribution valve so that the calculated degree of overcooling becomes the target degree of overcooling.

Further, the refrigerant temperature adjusting means of the hot water supply system is connected to a temperature sensor that detects the temperature of the liquid refrigerant flowing into the expansion valve and the water circulation line, and supplies circulating water to the first heat dissipation heat exchanger. A fourth bypass line for bypassing, and a fourth distribution valve for adjusting the distribution amount of the circulating water supplied to the first heat dissipation heat exchanger and the circulating water supplied to the fourth bypass line are provided. It is preferable that the control means controls the fourth distribution valve so that the detection temperature of the temperature sensor reaches the target temperature while the compressor is being driven.

Further, the refrigerant temperature adjusting means of the hot water supply system includes a temperature sensor that detects the temperature of the liquid refrigerant flowing into the expansion valve, a pressure sensor that detects the pressure of the liquid refrigerant flowing into the expansion valve, and the water circulation line. A fourth bypass line that is connected and bypasses the circulating water to the first heat dissipation heat exchanger, circulating water to be supplied to the first heat dissipation heat exchanger, and circulation to be supplied to the fourth bypass line. A fourth distribution valve for adjusting the distribution amount of water is provided, and the control means obtains the condensation temperature of the gas refrigerant from the detection pressure of the pressure sensor while the compressor is being driven, and the temperature is derived from the condensation temperature. It is preferable to calculate the degree of supercooling of the liquid refrigerant by subtracting the detection temperature of the sensor, and control the fourth distribution valve so that the calculated degree of supercooling becomes the target degree of supercooling.

According to the present invention, it is possible to provide a hot water supply system capable of preventing damage to the compressor in a configuration in which a heat exchanger for heating stored water and a heat exchanger for heating make-up water are provided in a heat pump circuit.

It is a figure which shows typically the structure of the hot water supply system which concerns on 1st Embodiment of this invention. It is a figure which shows typically the structure of the hot water supply system which concerns on the modification of the said embodiment. It is a figure which shows typically the structure of the hot water supply system which concerns on 2nd Embodiment of this invention. It is a figure which shows typically the structure of the hot water supply system which concerns on the modification of the said embodiment. It is a figure which shows typically the structure of the hot water supply system which concerns on 3rd Embodiment of this invention. It is a figure which shows typically the structure of the hot water supply system which concerns on the modification of the said embodiment. It is a figure which shows typically the structure of the hot water supply system which concerns on 4th Embodiment of this invention. It is a figure which shows typically the structure of the hot water supply system which concerns on the modification of the said embodiment.

<First Embodiment>
Hereinafter, the first embodiment of the hot water supply system 1 of the present invention will be described with reference to the drawings. The term "line" as used herein is a general term for lines capable of flowing fluids such as flow paths, routes, and pipelines.

FIG. 1 is a diagram schematically showing a configuration of a hot water supply system 1 according to the present embodiment. As shown in FIG. 1, the hot water supply system 1 of the present embodiment includes a heat pump circuit 10, a hot water storage tank 60, a water circulation line L1 that circulates the stored water W3 in the hot water storage tank 60 as circulating water W1, and make-up water W2. A make-up water line L2 for supplying to the hot water storage tank 60 and a control unit 100 are provided.
The hot water supply system 1 is a system that supplies the stored water W3 in the hot water storage tank 60 heated by the heat pump circuit 10 as hot water supply water W4 to a hot water demand point or a hot water demand place.

The heat pump circuit 10 includes a compressor 11, a first heat heat exchanger 12A (condenser 12A), a second heat exchanger 12B (supercooler 12B), an expansion valve 13, and a heat absorption heat exchanger 14 (evaporation). The vessel 14) is annularly connected by the refrigerant circulation line L9, and is absorbed by the heat absorption heat exchanger 14 by the drive of the compressor 11 and is absorbed by the first heat dissipation heat exchanger 12A and / or the second heat dissipation heat exchanger 12B. It is a steam compression type heat pump circuit that takes out heat. Refrigerant R flows through the refrigerant circulation line L9.

The compressor 11 has an electric motor 15 as a drive source, and compresses a gaseous refrigerant R (gas refrigerant R) such as Freon gas into a high-temperature and high-pressure refrigerant R. The first heat exchanger 12A is a condenser that dissipates heat to the circulating water W1 sent through the water circulation line L1 and condenses the refrigerant R from the compressor 11. The second heat exchanger 12B dissipates heat to the make-up water W2 sent through the make-up water line L2, and supercools the refrigerant R (liquid refrigerant R) that has passed through the first heat exchanger 12A. It is a cooler. The expansion valve 13 reduces the pressure and temperature of the refrigerant R by passing the refrigerant R sent from the second heat dissipation heat exchanger 12B. The endothermic heat exchanger 14 is an evaporator that absorbs heat from the heat source fluid and evaporates the refrigerant R sent from the expansion valve 13. As the heat source fluid, various fluids such as heat source air and heat source water can be used.

The first heat radiating heat exchanger 12A for heating the stored water indirectly exchanges heat between the circulating water W1 and the refrigerant R, and dissipates the latent heat and sensible heat of the refrigerant R. The first heat exchanger 12A condenses and liquefies the refrigerant R using the circulating water W1 and heats the circulating water W1 using the refrigerant R.
The second heat radiating heat exchanger 12B for heating the make-up water indirectly exchanges heat between the make-up water W2 and the refrigerant R, and dissipates the apparent heat of the refrigerant R. The second heat exchanger 12B supercools the refrigerant R using the make-up water W2 and heats the make-up water W2 using the refrigerant R.
As described above, by separating the heat exchanger for the condensation and the supercooling of the refrigerant R, the design of the heat exchanger can be facilitated and the cost can be reduced. In addition, a general-purpose heat exchanger can be used.
If the condensed liquefaction of the gas refrigerant R in the first heat exchanger 12A stops at a partial phase change due to operating conditions or the like, the remaining gas refrigerant R in the second heat exchanger 12B Condensation is performed.

The expansion valve 13 is configured as a proportionally controlled needle valve, and the stroke of the needle valve is changed by controlling the rotation speed of the drive stepping motor to adjust the valve opening degree, thereby adjusting the flow rate of the refrigerant R flowing through the refrigerant circulation line L9. Can be adjusted.

As described above, in the heat absorption heat exchanger 14, the refrigerant R takes heat from the outside and vaporizes, while in the first heat dissipation heat exchanger 12A and the second heat dissipation heat exchanger 12B, the heat pump circuit 10 takes heat from the outside and vaporizes it. The refrigerant R dissipates heat to the outside, condenses and liquefies, and is overcooled. Using such a principle, the heat pump circuit 10 draws heat from the heat source fluid by the endothermic heat exchanger 14, heats the circulating water W1 by the first heat exchanger 12A, and heats the second heat dissipation. The make-up water W2 is heated by the exchanger 12B.

The heat pump circuit 10 of the present embodiment is further connected to a refrigerant temperature sensor 16 as a temperature sensor for detecting the temperature of the liquid refrigerant R flowing into the expansion valve 13 and a refrigerant circulation line L9, and is connected to a second heat exchanger 12B for heat dissipation. The distribution amount of the first bypass line L11 for bypassing the liquid refrigerant R, the liquid refrigerant R to be supplied to the second heat exchanger 12B, and the liquid refrigerant R to be supplied to the first bypass line L11 is adjusted. A first distribution valve 31 is provided.

The first bypass line L11 branches from the refrigerant circulation line L9 on the upstream side of the second heat dissipation heat exchanger 12B (between the first heat dissipation heat exchanger 12A and the second heat dissipation heat exchanger 12B), and is the second. 2 On the downstream side of the heat exchanger 12B for heat dissipation (between the second heat exchanger 12B for heat dissipation and the expansion valve 13), the heat exchanger 12B merges with the refrigerant circulation line L9.

The refrigerant temperature sensor 16 is located on the downstream side of the confluence of the refrigerant circulation line L9 and the first bypass line L11, and is arranged on the upstream side of the expansion valve 13. More preferably, the refrigerant temperature sensor 16 is arranged on the upstream side of the expansion valve 13 and in the vicinity of the expansion valve 13 in order to measure the temperature of the refrigerant R immediately before flowing into the expansion valve 13.

The first distribution valve 31 is provided on the first bypass line L11. The first distribution valve 31 is configured so that the valve opening degree can be adjusted. By adjusting the valve opening degree of the first distribution valve 31, the distribution amount of the liquid refrigerant R supplied to the second heat exchanger 12B for heat dissipation and the liquid refrigerant R supplied to the first bypass line L11 is adjusted. Can be done.
Here, when the first distribution valve 31 is opened, of the refrigerant R flowing through the refrigerant circulation line L9, the first diversion flow flowing through the first bypass line L11 is relatively in the process of passing through the first distribution valve 31. Only a small friction loss is received in the valve chamber. On the other hand, the second diversion flow flowing through the refrigerant circulation line L9 in which the second heat exchanger 12B for heat dissipation is arranged causes a relatively large friction loss in the process of passing through the second heat exchanger 12B for heat dissipation for the second heat dissipation. It will be received in the heat exchanger 12B. Therefore, the flow rate ratio of the refrigerant R is "first diversion> second diversion", and most of the refrigerant R flows on the first bypass line L11 side. Therefore, even with such a simple configuration, by adjusting the valve opening degree of the first distribution valve 31, the liquid refrigerant R and the first bypass line L11 to be supplied to the second heat exchanger 12B for heat dissipation are supplied. The amount of liquid refrigerant R to be distributed can be adjusted.

These refrigerant temperature sensors 16, the first bypass line L11, and the first distribution valve 31 constitute the refrigerant temperature adjusting means 50 in the present embodiment. The refrigerant temperature adjusting means 50 is controlled by a control unit 100 described later, and adjusts the temperature of the liquid refrigerant R flowing into the expansion valve 13.

The hot water storage tank 60 is a tank that stores the circulating water W1 and the make-up water W2 heated by the heat pump circuit 10 as the stored water W3. The stored water W3 in the hot water storage tank 60 is supplied as hot water supply water W4 to a hot water demand point or a hot water demand point through a hot water supply water line L4.

The hot water storage tank 60 includes a hot water storage temperature sensor 61 that detects the temperature of the stored water W3 in the hot water storage tank 60. The hot water storage temperature sensor 61 monitors the temperature of the stored water W3 that will be supplied to the hot water demand point or the hot water demand point as the hot water supply water W4.

The hot water storage tank 60 includes a water level sensor 62 that detects the water level in the hot water storage tank 60. In the present embodiment, the water level sensor 62 is composed of an electrode type water level detector including a plurality of electrode rods. Specifically, a plurality of electrode rods having different lengths are inserted and held at different height positions of the lower end portions thereof. Each electrode rod detects the presence or absence of a water level at the lower end portion depending on whether or not the lower end portion thereof is immersed in water. As a result, the water level sensor 62 detects the water level of the stored water W3 in the hot water storage tank 60.

The upstream side of the water circulation line L1 is connected to the hot water storage tank 60, and the downstream side is also connected to the hot water storage tank 60. The water circulation line L1 forms a circulation path for circulating the stored water W3 in the hot water storage tank 60 as the circulating water W1. The stored water W3 in the hot water storage tank 60 passes through the first heat dissipation heat exchanger 12A through the water circulation line L1 to be heated, and returns to the hot water storage tank 60. In the water circulation line L1, the water circulation pump 21, the first heat exchanger 12A for heat dissipation, and the first temperature sensor 22 are sequentially arranged from the upstream side.

The rotation speed of the water circulation pump 21 can be controlled by an inverter. By changing the rotation speed of the water circulation pump 21, the flow rate of the circulating water W1 circulating in the water circulation line L1 can be adjusted.

The first temperature sensor 22 is arranged on the downstream side of the first heat radiating heat exchanger 12A, and detects the temperature of the circulating water W1 flowing out of the first heat radiating heat exchanger 12A.

The upstream side of the make-up water line L2 is connected to a make-up water source such as a make-up water tank (not shown), and the downstream side thereof is connected to the hot water storage tank 60. The make-up water line L2 is a line that supplies the make-up water W2 to the hot water storage tank 60 while circulating the make-up water W2 to the second heat exchanger 12B. In the make-up water line L2, a make-up water valve 25, a second heat exchanger 12B for heat dissipation, and a second temperature sensor 26 are sequentially arranged from the upstream side.

The make-up water valve 25 is configured so that the valve opening can be adjusted. By adjusting the valve opening degree of the make-up water valve 25, the flow rate of the make-up water W2 flowing through the make-up water line L2 can be adjusted.

The second temperature sensor 26 is arranged on the downstream side of the second heat exchanger 12B for heat dissipation, and detects the temperature of the make-up water W2 flowing out from the second heat exchanger 12B for heat dissipation.

The make-up water line L2 includes a second bypass line L12 as a make-up water bypass line. The second bypass line L12 is a bypass line that bypasses the make-up water W2 to the second heat dissipation heat exchanger 12B. A second distribution valve 32 as a make-up water distribution valve is arranged on the second bypass line L12.

The second distribution valve 32 adjusts the distribution amount of the make-up water W2 to be sent to the second heat exchanger 12B and the make-up water W2 to be sent to the second bypass line L12. The valve opening degree of the second distribution valve 32 may be adjusted by automatic or manual input. For example, when it is detected that the water level of the stored water W3 in the hot water storage tank 60 has dropped sharply, the second distribution valve 32 may be opened by automatic or manual input. As a result, the make-up water W2 that has not been heated by the second heat radiating heat exchanger 12B is rapidly replenished in the hot water storage tank 60, and the hot water storage tank 60 is prevented from becoming drought.

The stored water W3 in the hot water storage tank 60 heated by passing through the water circulation line L1 and the make-up water line L2 is supplied as hot water supply water W4 to the hot water demand point or the hot water demand point through the hot water supply water line L4.

The hot water demand point refers to various production facilities in the factory that consume the stored water W3 by using the hot water supply water W4 as a fluid. Examples of hot water demand locations include container cleaning equipment (rincers) for food, beverages, and chemicals, and heat sterilization equipment (pastorizers) for bottled, canned, and bagged products.
On the other hand, the thermal demand location refers to a production facility or the like that uses only the thermal energy of the hot water supply water W4 and does not consume the stored water W3. The use of heat energy is performed via various heat exchangers, and the hot water supply water W4 whose temperature has dropped due to the extraction of heat energy is returned to the hot water storage tank 60 through a hot water return water line (not shown). Examples of hot demand points include degreasing tanks and chemical conversion tanks in coating equipment for metal processed products, air handling units in air conditioning equipment, and the like.

Next, the control unit 100 (control means 100) of the hot water supply system 1 of the present embodiment will be described. The control unit 100 is composed of a microprocessor including a CPU and a memory. The control unit 100 includes a water circulation pump control unit 110 as a circulating water flow rate control unit, a make-up water valve control unit 120 as a make-up water flow rate control unit, and a distribution valve control unit 130 as a refrigerant temperature control unit as functional blocks. , Equipped with.
Here, the broken line in FIG. 1 shows the main electrical connection path in the present embodiment. Although these electrical connections actually go through the control unit 100, that point is omitted.

The water circulation pump control unit 110 acquires the detected temperature of the first temperature sensor 22, and controls the drive frequency of the water circulation pump 21 constituting the circulating water flow rate adjusting means according to the detected temperature. Specifically, the water circulation pump control unit 110 controls the drive frequency of the water circulation pump 21 so that the detected temperature of the first temperature sensor 22 becomes the target hot water discharge temperature, and adjusts the flow rate of the circulating water W1. As a more specific control, for example, the feedback control that adjusts the drive frequency of the water circulation pump so that the outlet temperature is converged to the target outlet temperature by using the outlet temperature detected in real time by the first temperature sensor 22 as a feedback value. It is preferable to adopt. As the feedback control, in addition to the proportional control (P control), an operation amount calculation algorithm that combines the integral control (I control) and / or the differential control (D control) can be adopted.

As a result, the circulating water W1 supplied from the hot water storage tank 60 to the first heat dissipation heat exchanger 12A is heated to the target hot water discharge temperature (for example, 60 ° C.) by the first heat dissipation heat exchanger 12A, and then the hot water storage tank 60. Is refluxed at a constant temperature. Therefore, when the temperature of the heat source fluid (for example, heat source air) supplied to the heat absorption heat exchanger 14 fluctuates seasonally, or when the temperature of the make-up water W2 after heating by the second heat dissipation heat exchanger 12B fluctuates. However, hot water having a required temperature (for example, a hot water supply temperature required at a hot water demanding place or a hot water demanding place) can be stored at high speed in the hot water storage tank 60.

The make-up water valve control unit 120 acquires the water level information of the stored water W3 in the hot water storage tank 60 detected by the water level sensor 62, and the valve of the make-up water valve 25 constituting the make-up water flow rate adjusting means according to the water level information. Control to adjust the opening. Specifically, the make-up water valve control unit 120 reduces the opening degree of the make-up water valve 25 to reduce the make-up water flow rate as the detected water level of the water level sensor 62 becomes higher, while the lower the detected water level of the water level sensor 62 becomes. Control is performed to increase the valve opening degree of the make-up water valve 25 to increase the make-up water flow rate. For example, when the water level is full, the valve opening of the make-up water valve 25 is set to 0% (fully closed), and when the water level is just before the drought, the valve opening of the make-up water valve 25 is set to 100% (fully open). ), And when the water level is in the middle, the valve opening of the make-up water valve 25 is set to 5% to 95%.

In this way, the valve opening of the make-up water valve 25 is decreased as the detected water level of the water level sensor 62 is higher, while the valve opening of the make-up water valve 25 is increased as the detected water level of the water level sensor 62 is lower. Therefore, the make-up water flow rate is increased or decreased in response to the increase or decrease in the hot water demand. That is, the make-up water valve 25 is not closed unless the hot water demand becomes zero, and the make-up water W2 continues to flow in the second heat dissipation heat exchanger 12B. As a result, even when the demand for hot water is small, the supercooling of the liquid refrigerant R can be continued and the COP can be increased.

The make-up water valve control unit 120 is based on the detection temperature of the second temperature sensor 26 that detects the temperature of the make-up water W2 flowing out from the second heat dissipation heat exchanger 12B in addition to the detected water level of the water level sensor 62. , The valve opening degree of the make-up water valve 25 may be controlled. In this case, the make-up water valve control unit 120 adjusts the valve opening degree of the make-up water valve 25 constituting the make-up water flow rate adjusting means according to the water level information detected by the water level sensor 62, and the second temperature sensor 26. If the detected temperature of the second temperature sensor 26 exceeds the target hot water discharge temperature (for example, 60 ° C.) of the first heat dissipation heat exchanger 12A, the detected temperature of the second temperature sensor 26 is the target hot water discharge temperature (for example, 60 ° C.). The valve opening degree of the make-up water valve 25 is controlled so as not to exceed the range. As a result, while continuing supercooling of the liquid refrigerant R, hot water that does not exceed the required temperature (for example, the hot water supply temperature required at the hot water demand location or the hot water demand location) can be supplied to the hot water storage tank 60 at high speed.

The distribution valve control unit 130 acquires the detection temperature of the refrigerant temperature sensor 16 and controls to adjust the valve opening degree of the first distribution valve 31 constituting the refrigerant temperature adjusting means 50 according to the detected temperature. Specifically, the distribution valve control unit 130 controls the first distribution valve 31 so that the detection temperature of the refrigerant temperature sensor 16 reaches the target temperature while the compressor 11 is being driven. As a more specific control, for example, the refrigerant temperature detected in real time by the refrigerant temperature sensor 16 is used as a feedback value, and the valve opening degree of the first distribution valve 31 is adjusted so that the refrigerant temperature converges to the target temperature. It is preferable to adopt feedback control. As the feedback control, in addition to the proportional control (P control), an operation amount calculation algorithm that combines the integral control (I control) and / or the differential control (D control) can be adopted.
Here, the target temperature is set manually or automatically according to the state of the device or the like.
As a result, the bypass amount of the liquid refrigerant R with respect to the second heat radiating heat exchanger 12B is adjusted, and the cooling amount of the liquid refrigerant R in the second heat radiating heat exchanger 12B is suppressed.

With the above configuration, even when the water source temperature of the make-up water is low, the temperature of the liquid refrigerant R flowing into the expansion valve can be maintained at a constant temperature that does not cause a high supercooling state. Therefore, it is avoided that the liquid refrigerant R in the highly supercooled state is supplied to the endothermic heat exchanger 14, and the compressor 11 does not have an obstacle to suck the refrigerant R in the wet vapor state. This makes it possible to optimally operate the refrigeration cycle while preventing damage to the compressor 11.

Subsequently, a modified example of the first embodiment will be described with reference to the drawings. FIG. 2 is a diagram schematically showing a configuration of a hot water supply system according to a modified example of the first embodiment. In this modification, a refrigerant pressure sensor 17 for detecting the pressure of the liquid refrigerant R flowing into the expansion valve 13 is further provided, and the distribution valve control unit 130 includes the detection temperature of the refrigerant temperature sensor 16 and the detection pressure of the refrigerant pressure sensor 17. The first distribution valve 31 is controlled based on the above.

As shown in FIG. 2, the heat pump circuit 10 of this modification includes a refrigerant pressure sensor 17 that detects the pressure of the liquid refrigerant R flowing into the expansion valve 13. Further, the control unit 100 of this modification includes a supercooling degree calculation unit 140 that calculates the supercooling degree of the liquid refrigerant R flowing into the expansion valve 13.

Like the refrigerant temperature sensor 16, the refrigerant pressure sensor 17 is located on the downstream side of the confluence of the refrigerant circulation line L9 and the first bypass line L11, and is arranged on the upstream side of the expansion valve 13. More preferably, the refrigerant pressure sensor 17 is arranged on the upstream side of the expansion valve 13 and in the vicinity of the expansion valve 13 in order to measure the pressure of the refrigerant R immediately before flowing into the expansion valve 13.

In this modification, the refrigerant pressure sensor 17, the refrigerant temperature sensor 16, the first bypass line L11, and the first distribution valve 31 constitute the refrigerant temperature adjusting means 50.

The supercooling degree calculation unit 140 calculates the supercooling degree of the liquid refrigerant R flowing into the expansion valve 13. Specifically, the supercooling degree calculation unit 140 obtains the condensation temperature of the gas refrigerant R from the detection pressure of the refrigerant pressure sensor 17, and subtracts the detection temperature of the refrigerant temperature sensor 16 from this condensation temperature to obtain the excess of the liquid refrigerant R. Calculate the degree of cooling.

The distribution valve control unit 130 controls the first distribution valve 31 constituting the refrigerant temperature adjusting means 50 so that the calculated supercooling degree (value calculated by the supercooling degree calculation unit 140) becomes the target supercooling degree, and is an expansion valve. The degree of supercooling of the liquid refrigerant R flowing into 13 is adjusted. As specific control, for example, the calculated supercooling degree calculated in real time by the supercooling degree calculation unit 140 is used as a feedback value, and the first distribution valve 31 so as to converge this calculated supercooling degree to the target supercooling degree. It is preferable to adopt feedback control that adjusts the valve opening of the valve. As the feedback control, in addition to the proportional control (P control), an operation amount calculation algorithm that combines the integral control (I control) and / or the differential control (D control) can be adopted.
As a result, the bypass amount of the liquid refrigerant R with respect to the second heat dissipation heat exchanger 12B is adjusted, and the degree of supercooling of the liquid refrigerant R flowing into the expansion valve 13 is adjusted.
Here, the target supercooling degree is set manually or automatically according to the state of the device or the like.

In this way, the supercooling degree calculation unit 140 accurately calculates the supercooling degree of the liquid refrigerant R flowing into the expansion valve 13, and the distribution valve control unit 130 further calculates the calculated supercooling degree to be the target supercooling degree. By controlling the first distribution valve 31, the amount of bypass of the liquid refrigerant R to the second heat exchanger 12B is adjusted, and the cooling amount of the liquid refrigerant R in the second heat exchanger 12B is suppressed. To. As a result, even when the water source temperature of the make-up water W2 is low, the temperature of the liquid refrigerant R flowing into the expansion valve 13 can be maintained at a constant temperature that does not cause a high supercooling state.

In the present embodiment, the first distribution valve 31 is provided on the first bypass line L11, but the present invention is not limited to this. The first distribution valve 31 may have a function of adjusting the distribution amount of the liquid refrigerant R supplied to the second heat exchanger 12B and the liquid refrigerant R supplied to the first bypass line L11. For example, it may be a three-way valve provided at a branch portion where the first bypass line L11 branches from the refrigerant circulation line L9.
In the case of a three-way valve, the valve opening on the first outlet port side toward the second heat exchanger 12B is opened by inputting a valve opening designation signal of 0 to 100% to the actuator circuit that adjusts the valve opening. The degree and the valve opening degree on the second outlet port side toward the first bypass line L11 are adjusted. As a result, the flow rate ratio between the flow rate of the liquid refrigerant R flowing through the second heat exchanger 12B and the flow rate of the liquid refrigerant R flowing through the first bypass line L11 is adjusted. However, the total flow rate ratio on the first outlet port side and the second outlet port side is always 100%. The valve opening of the three-way valve is based on the valve opening on the first outlet port side, and the valve opening on the first outlet port side is 0% → 25% → 50% → 75% → 100. When it becomes%, the valve opening degree on the second outlet port side becomes 100% → 75% → 50% → 25% → 0%. Also in the case of using such a three-way valve, for example, the refrigerant temperature detected in real time by the refrigerant temperature sensor 16 and the calculated supercooling degree calculated in real time by the supercooling degree calculation unit 140 are used as feedback values. It is preferable to adopt feedback control that adjusts the valve opening of the three-way valve so that the refrigerant temperature and the calculated supercooling degree converge to the target value.

According to the hot water supply system 1 of the first embodiment described above, the effects shown in the following (1) to (3) are obtained.

(1) In the hot water supply system 1 of the present embodiment, the compressor 11, the first heat heat exchanger 12A, the second heat exchanger 12B, the expansion valve 13, and the heat absorption heat exchanger 14 are provided by the refrigerant circulation line L9. A steam compression type heat pump circuit 10 that is connected in an annular shape and takes out heat by the first heat exchanger 12A and / or the second heat exchanger 12B by driving the compressor 11, and hot water storage for storing the make-up water W2. The tank 60, the water circulation line L1 that circulates the stored water W3 in the hot water storage tank 60 to the first heat exchanger 12A, and the make-up water W2 to the hot water storage tank 60 while circulating the make-up water W2 to the second heat exchanger 12B. A make-up water line L2 to be supplied, a refrigerant temperature adjusting means 50 for adjusting the temperature of the liquid refrigerant R flowing into the expansion valve 13, and a control means 100 for controlling the refrigerant temperature adjusting means 50 are provided.
As described above, since the refrigerant temperature adjusting means 50 for adjusting the temperature of the liquid refrigerant R flowing into the expansion valve 13 and the control means 100 for controlling the refrigerant temperature adjusting means 50 are provided, the heat absorption heat exchanger 14 is provided. It is avoided that the refrigerant R in the highly overcooled state is supplied to the (evaporator 14), and the compressor 11 does not have an obstacle to suck the moist steam. This makes it possible to optimally operate the refrigeration cycle while preventing damage to the compressor 11.

(2) The refrigerant temperature adjusting means 50 of the hot water supply system 1 of the present embodiment is connected to a temperature sensor 16 for detecting the temperature of the liquid refrigerant R flowing into the expansion valve 13 and a refrigerant circulation line L9, and is connected to a second heat dissipation heat. Adjust the distribution amount of the first bypass line L11 for bypassing the refrigerant R to the exchanger 12B, the refrigerant R to be fed to the second heat dissipation heat exchanger 12B, and the refrigerant R to be fed to the first bypass line L11. The control means 100 includes the first distribution valve 31 and controls the first distribution valve 31 so that the detection temperature of the temperature sensor 16 reaches the target temperature while the compressor 11 is being driven.
In this way, by controlling the first distribution valve 31 so that the detection temperature of the refrigerant R flowing into the expansion valve 13 becomes the target temperature, the bypass amount of the refrigerant R with respect to the second heat dissipation heat exchanger 12B is adjusted. , The amount of cooling of the refrigerant R in the second heat exchanger 12B for heat dissipation is suppressed. As a result, even when the water source temperature of the make-up water W2 is low, the temperature of the liquid refrigerant R flowing into the expansion valve 13 can be maintained at a constant temperature that does not cause a high supercooling state.

(3) The refrigerant temperature adjusting means 50 of the hot water supply system 1 of the present embodiment detects the pressure of the liquid refrigerant R flowing into the expansion valve 13 and the temperature sensor 16 for detecting the temperature of the liquid refrigerant R flowing into the expansion valve 13. The refrigerant to be supplied to the first bypass line L11, which is connected to the refrigerant circulation line L9 and bypasses the refrigerant R to the second heat dissipation heat exchanger 12B, and the second heat dissipation heat exchanger 12B. A first distribution valve 31 for adjusting the distribution amount of the refrigerant R to be supplied to the R and the first bypass line L11 is provided, and the control means 100 is a gas refrigerant from the detection pressure of the pressure sensor 17 while the compressor 11 is being driven. The first distribution valve is calculated by subtracting the detection temperature of the temperature sensor 16 from the condensation temperature to calculate the overcooling degree of the liquid refrigerant R so that the calculated overcooling degree becomes the target overcooling degree. 31 is controlled.
In this way, by controlling the first distribution valve 31 so that the calculated supercooling degree of the refrigerant R flowing into the expansion valve 13 becomes the target supercooling degree, the refrigerant R is bypassed with respect to the second heat dissipation heat exchanger 12B. The amount is adjusted, and the cooling amount of the refrigerant R in the second heat dissipation heat exchanger 12B is suppressed. As a result, even when the water source temperature of the make-up water W2 is low, the temperature of the liquid refrigerant R flowing into the expansion valve 13 can be maintained at a constant temperature that does not cause a high supercooling state.

<Second Embodiment>
Next, the second embodiment will be described with reference to the drawings. FIG. 3 is a diagram schematically showing the configuration of the hot water supply system 1 in the present embodiment. In the present embodiment, the same components as those in the first embodiment may be designated by the same reference numerals and the description thereof may be omitted.

As shown in FIG. 3, the heat pump circuit 10 of the present embodiment does not include the first bypass line L11 and the first distribution valve 31.
In the present embodiment, the refrigerant temperature sensor 16, the second bypass line L12, and the second distribution valve 32 constitute the refrigerant temperature adjusting means 50.

As described above, the second bypass line L12 is a line that bypasses the make-up water W2 to the second heat dissipation heat exchanger 12B.
The second distribution valve 32 is a valve that adjusts the distribution amount of the make-up water W2 to be supplied to the second heat dissipation heat exchanger 12B and the make-up water W2 to be supplied to the second bypass line L12. The second distribution valve 32 of the present embodiment is controlled by the distribution valve control unit 130 of the control unit 100.

The distribution valve control unit 130 of the present embodiment acquires the detection temperature of the refrigerant temperature sensor 16, and according to the detected temperature, the valve opening degree of the second distribution valve 32 constituting the refrigerant temperature adjusting means 50 of the present embodiment. Control to adjust. Specifically, the distribution valve control unit 130 controls the second distribution valve 32 so that the detection temperature of the refrigerant temperature sensor 16 reaches the target temperature while the compressor 11 is being driven. As a more specific control, for example, the refrigerant temperature detected in real time by the refrigerant temperature sensor 16 is used as a feedback value, and the valve opening degree of the second distribution valve 32 is adjusted so that the refrigerant temperature converges to the target temperature. It is preferable to adopt feedback control. As the feedback control, in addition to the proportional control (P control), an operation amount calculation algorithm that combines the integral control (I control) and / or the differential control (D control) can be adopted.
As a result, the bypass amount of the make-up water W2 with respect to the second heat dissipation heat exchanger 12B is adjusted, and the temperature of the liquid refrigerant R flowing into the expansion valve 13 is adjusted.

With the above configuration, even when the water source temperature of the make-up water is low, the temperature of the liquid refrigerant R flowing into the expansion valve can be maintained at a constant temperature that does not cause a high supercooling state. Therefore, it is avoided that the liquid refrigerant R in the highly supercooled state is supplied to the endothermic heat exchanger 14, and the compressor 11 does not have an obstacle to suck the refrigerant R in the wet vapor state. This makes it possible to optimally operate the refrigeration cycle while preventing damage to the compressor 11.

Subsequently, a modified example of the second embodiment will be described with reference to the drawings. FIG. 4 is a diagram schematically showing a configuration of a hot water supply system according to a modified example of the second embodiment.

As shown in FIG. 4, the heat pump circuit 10 of this modified example includes a refrigerant pressure sensor 17 that detects the pressure of the liquid refrigerant R flowing into the expansion valve 13, as in the modified example of the first embodiment. Further, the control unit 100 of this modification includes a supercooling degree calculation unit 140 as in the modification of the first embodiment.

In this modification, the refrigerant pressure sensor 17, the refrigerant temperature sensor 16, the second bypass line L12, and the second distribution valve 32 constitute the refrigerant temperature adjusting means 50.

The distribution valve control unit 130 of the present embodiment controls the second distribution valve 32 based on the detection temperature of the refrigerant temperature sensor 16 and the detection pressure of the refrigerant pressure sensor 17. Specifically, the distribution valve control unit 130 of this modification controls the second distribution valve 32 so that the calculated supercooling degree calculated by the supercooling degree calculation unit 140 becomes the target supercooling degree, and the expansion valve 13 The degree of supercooling of the liquid refrigerant R flowing into the water is adjusted. Also in this case, the calculated supercooling degree calculated in real time by the supercooling degree calculation unit 140 is used as a feedback value, and the valve opening degree of the second distribution valve 32 is set so as to converge this calculated supercooling degree to the target supercooling degree. It is preferable to adopt a feedback control that adjusts.

In this way, the supercooling degree calculation unit 140 accurately calculates the supercooling degree of the liquid refrigerant R flowing into the expansion valve 13, and the distribution valve control unit 130 further calculates the calculated supercooling degree to be the target supercooling degree. By controlling the second distribution valve 32, the amount of bypass of the make-up water W2 with respect to the second heat exchanger 12B is adjusted, and the cooling amount of the liquid refrigerant R in the second heat exchanger 12B is suppressed. To. As a result, even when the water source temperature of the make-up water W2 is low, the temperature of the liquid refrigerant R flowing into the expansion valve 13 can be maintained at a constant temperature that does not cause a high supercooling state.

Also in this embodiment, the second distribution valve 32 is not limited to the mode provided in the second bypass line L12. For example, the second distribution valve 32 may be a three-way valve provided at a branch portion where the second bypass line L12 branches from the make-up water line L2.

According to the hot water supply system 1 of the second embodiment described above, in addition to (1), the following effects are obtained.

(4) The refrigerant temperature adjusting means 50 of the hot water supply system 1 of the present embodiment is connected to a temperature sensor 16 for detecting the temperature of the liquid refrigerant R flowing into the expansion valve 13 and a make-up water line L2, and is connected to a second heat dissipation heat. Distribution amount of the second bypass line L12 that bypasses the make-up water W2 to the exchanger 12B, the make-up water W2 that is sent to the second heat dissipation heat exchanger 12B, and the make-up water W2 that is sent to the second bypass line L12. The control means 100 controls the second distribution valve 32 so that the detection temperature of the temperature sensor 16 becomes the target temperature while the compressor 11 is being driven.
In this way, by controlling the second distribution valve 32 so that the detection temperature of the refrigerant R flowing into the expansion valve 13 becomes the target temperature, the bypass amount of the make-up water W2 with respect to the second heat dissipation heat exchanger 12B is adjusted. Therefore, the amount of cooling of the refrigerant R in the second heat exchanger 12B for heat dissipation is suppressed. As a result, even when the water source temperature of the make-up water W2 is low, the temperature of the liquid refrigerant R flowing into the expansion valve 13 can be maintained at a constant temperature that does not cause a high supercooling state.

(5) The refrigerant temperature adjusting means 50 of the hot water supply system 1 of the present embodiment detects the pressure of the temperature sensor 16 that detects the temperature of the liquid refrigerant R flowing into the expansion valve 13 and the pressure of the liquid refrigerant R flowing into the expansion valve 13. The pressure sensor 17 and the second bypass line L12, which are connected to the make-up water line L2 and bypass the make-up water W2 to the second heat radiating heat exchanger 12B, and the second heat radiating heat exchanger 12B are supplied. A second distribution valve 32 for adjusting the distribution amount of the make-up water W2 and the make-up water W2 to be supplied to the make-up water W2 and the second bypass line L12 is provided. The condensation temperature of the gas refrigerant R is obtained from, and the overcooling degree of the liquid refrigerant R is calculated by subtracting the detection temperature of the temperature sensor 16 from the condensation temperature so that the calculated overcooling degree becomes the target overcooling degree. The second distribution valve 32 is controlled.
In this way, by controlling the second distribution valve 32 so that the calculated supercooling degree of the refrigerant R flowing into the expansion valve 13 becomes the target supercooling degree, the make-up water W2 for the second heat dissipation heat exchanger 12B The bypass amount is adjusted, and the cooling amount of the refrigerant R in the second heat dissipation heat exchanger 12B is suppressed. As a result, even when the water source temperature of the make-up water W2 is low, the temperature of the liquid refrigerant R flowing into the expansion valve 13 can be maintained at a constant temperature that does not cause a high supercooling state.

<Third Embodiment>
Next, the third embodiment will be described with reference to the drawings. FIG. 5 is a diagram schematically showing the configuration of the hot water supply system 1 in the present embodiment. In the present embodiment, the same components as those in the first embodiment may be designated by the same reference numerals and the description thereof may be omitted.

As shown in FIG. 5, the heat pump circuit 10 of the present embodiment does not include the first bypass line L11 and the first distribution valve 31. Instead, a third bypass line L13 and a third distribution valve 33 are provided.
In the present embodiment, the refrigerant temperature sensor 16, the third bypass line L13, and the third distribution valve 33 constitute the refrigerant temperature adjusting means 50.

The third bypass line L13 is a line for bypassing the refrigerant R with respect to the first heat dissipation heat exchanger 12A.
The third distribution valve 33 is a valve that adjusts the distribution amount of the refrigerant R to be supplied to the first heat dissipation heat exchanger 12A and the refrigerant R to be supplied to the third bypass line L13. The third distribution valve 33 of the present embodiment is controlled by the distribution valve control unit 130 of the control unit 100.

The distribution valve control unit 130 of the present embodiment acquires the detection temperature of the refrigerant temperature sensor 16, and according to the detected temperature, the valve opening degree of the third distribution valve 33 constituting the refrigerant temperature adjusting means 50 of the present embodiment. Control to adjust. Specifically, the distribution valve control unit 130 controls the third distribution valve 33 so that the detection temperature of the refrigerant temperature sensor 16 reaches the target temperature while the compressor 11 is being driven. As a more specific control, for example, the refrigerant temperature detected in real time by the refrigerant temperature sensor 16 is used as a feedback value, and the valve opening degree of the third distribution valve 33 is adjusted so that the refrigerant temperature converges to the target temperature. It is preferable to adopt feedback control. As the feedback control, in addition to the proportional control (P control), an operation amount calculation algorithm that combines the integral control (I control) and / or the differential control (D control) can be adopted.
As a result, the bypass amount of the refrigerant R with respect to the first heat dissipation heat exchanger 12A is adjusted, and the cooling amount of the refrigerant R in the first heat dissipation heat exchanger 12A is suppressed.
As a result of being bypassed, the refrigerant R that has not been condensed and liquefied in the first heat exchanger 12A is condensed and liquefied in the second heat exchanger 12B.

With the above configuration, even when the hot water storage temperature is set to a low temperature, the temperature of the liquid refrigerant R flowing into the expansion valve 13 can be maintained at a constant temperature that does not cause a high supercooling state. Therefore, it is avoided that the liquid refrigerant R in the highly supercooled state is supplied to the endothermic heat exchanger 14, and the compressor 11 does not have an obstacle to suck the refrigerant R in the wet vapor state. This makes it possible to optimally operate the refrigeration cycle while preventing damage to the compressor 11.

Subsequently, a modified example of the third embodiment will be described with reference to the drawings. FIG. 6 is a diagram schematically showing a configuration of a hot water supply system according to a modified example of the third embodiment.

As shown in FIG. 6, the heat pump circuit 10 of this modified example includes a refrigerant pressure sensor 17 that detects the pressure of the liquid refrigerant R flowing into the expansion valve 13, as in the modified example of the first embodiment. Further, the control unit 100 of this modification includes a supercooling degree calculation unit 140 as in the modification of the first embodiment.

In this modification, the refrigerant pressure sensor 17, the refrigerant temperature sensor 16, the third bypass line L13, and the third distribution valve 33 constitute the refrigerant temperature adjusting means 50.

The distribution valve control unit 130 of the present embodiment controls the third distribution valve 33 based on the detection temperature of the refrigerant temperature sensor 16 and the detection pressure of the refrigerant pressure sensor 17. Specifically, the distribution valve control unit 130 of this modification controls the third distribution valve 33 so that the calculated supercooling degree calculated by the supercooling degree calculation unit 140 becomes the target supercooling degree, and the expansion valve 13 The degree of supercooling of the liquid refrigerant R flowing into the water is adjusted. Also in this case, the calculated supercooling degree calculated in real time by the supercooling degree calculation unit 140 is used as a feedback value, and the valve opening degree of the third distribution valve 33 is set so as to converge this calculated supercooling degree to the target supercooling degree. It is preferable to adopt a feedback control that adjusts.

In this way, the supercooling degree calculation unit 140 accurately calculates the supercooling degree of the liquid refrigerant R flowing into the expansion valve 13, and the distribution valve control unit 130 further calculates the calculated supercooling degree to be the target supercooling degree. By controlling the third distribution valve 33, the bypass amount of the refrigerant R with respect to the first heat dissipation heat exchanger 12A is adjusted, and the cooling amount of the refrigerant R in the first heat dissipation heat exchanger 12A is suppressed. As a result, even when the hot water storage temperature is set to a low temperature, the temperature of the liquid refrigerant R flowing into the expansion valve 13 can be maintained at a constant temperature that does not result in a high supercooling state.

Also in this embodiment, the third distribution valve 33 is not limited to the mode provided in the third bypass line L13. For example, the third distribution valve 33 may be a three-way valve provided at a branch portion where the third bypass line L13 branches from the refrigerant circulation line L9.

According to the hot water supply system 1 of the third embodiment described above, in addition to (1), the following effects are obtained.

(6) The refrigerant temperature adjusting means 50 of the hot water supply system 1 of the present embodiment is connected to a temperature sensor 16 for detecting the temperature of the liquid refrigerant R flowing into the expansion valve 13 and a refrigerant circulation line L9, and is connected to the first heat dissipation heat. Adjust the distribution amount of the third bypass line L13 for bypassing the refrigerant R to the exchanger 12A, the refrigerant R to be supplied to the first heat dissipation heat exchanger 12A, and the refrigerant R to be supplied to the third bypass line L13. A third distribution valve 33 is provided, and the control means 100 controls the third distribution valve 33 so that the detection temperature of the temperature sensor 16 reaches the target temperature while the compressor 11 is being driven.
In this way, by controlling the third distribution valve 33 so that the detection temperature of the refrigerant R flowing into the expansion valve 13 becomes the target temperature, the bypass amount of the refrigerant R with respect to the first heat dissipation heat exchanger 12A is adjusted. , The amount of cooling of the refrigerant R in the first heat exchanger 12A for heat dissipation is suppressed. As a result, even when the hot water storage temperature is set to a low temperature, the temperature of the liquid refrigerant R flowing into the expansion valve 13 can be maintained at a constant temperature that does not result in a high supercooling state.

(7) The refrigerant temperature adjusting means 50 of the hot water supply system 1 of the present embodiment detects the pressure of the liquid refrigerant R flowing into the expansion valve 13 and the temperature sensor 16 for detecting the temperature of the liquid refrigerant R flowing into the expansion valve 13. The pressure sensor 17, the third bypass line L13, which is connected to the refrigerant circulation line L9 and bypasses the refrigerant R to the first heat dissipation heat exchanger 12A, and the refrigerant supplied to the first heat dissipation heat exchanger 12A. A third distribution valve 33 for adjusting the distribution amount of the refrigerant R to be supplied to the R and the third bypass line L13 is provided, and the control means 100 is a gas refrigerant from the detection pressure of the pressure sensor 17 while the compressor 11 is being driven. The condensation temperature of R is obtained, and the overcooling degree of the liquid refrigerant R is calculated by subtracting the detection temperature of the temperature sensor 16 from the condensation temperature, and the third distribution is performed so that the calculated overcooling degree becomes the target overcooling degree. Controls the valve 33.
In this way, by controlling the third distribution valve 33 so that the calculated supercooling degree of the refrigerant R flowing into the expansion valve 13 becomes the target supercooling degree, the refrigerant R is bypassed to the first heat dissipation heat exchanger 12A. The amount is adjusted, and the cooling amount of the refrigerant R in the first heat dissipation heat exchanger 12A is suppressed. As a result, even when the hot water storage temperature is set to a low temperature, the temperature of the liquid refrigerant R flowing into the expansion valve 13 can be maintained at a constant temperature that does not cause a high supercooling state.

<Fourth Embodiment>
Next, the fourth embodiment will be described with reference to the drawings. FIG. 7 is a diagram schematically showing the configuration of the hot water supply system 1 in the present embodiment. In the present embodiment, the same components as those in the first embodiment may be designated by the same reference numerals and the description thereof may be omitted.

As shown in FIG. 7, the heat pump circuit 10 of the present embodiment does not include the first bypass line L11 and the first distribution valve 31. Instead, it is provided with a fourth bypass line L14 and a fourth distribution valve 34.
In the present embodiment, the refrigerant temperature sensor 16, the fourth bypass line L14, and the fourth distribution valve 34 constitute the refrigerant temperature adjusting means 50.

The fourth bypass line L14 is a line that bypasses the circulating water W1 to the first heat exchanger 12A for heat dissipation.
The fourth distribution valve 34 is a valve that adjusts the distribution amount of the circulating water W1 supplied to the first heat dissipation heat exchanger 12A and the circulating water W1 supplied to the fourth bypass line L14. The fourth distribution valve 34 of the present embodiment is controlled by the distribution valve control unit 130 of the control unit 100.

The distribution valve control unit 130 of the present embodiment acquires the detected temperature of the refrigerant temperature sensor 16, and according to the detected temperature, the valve opening degree of the fourth distribution valve 34 constituting the refrigerant temperature adjusting means 50 of the present embodiment. Control to adjust. Specifically, the distribution valve control unit 130 controls the fourth distribution valve 34 so that the detection temperature of the refrigerant temperature sensor 16 reaches the target temperature while the compressor 11 is being driven. As a more specific control, for example, the refrigerant temperature detected in real time by the refrigerant temperature sensor 16 is used as a feedback value, and the valve opening degree of the fourth distribution valve 34 is adjusted so that the refrigerant temperature converges to the target temperature. It is preferable to adopt feedback control. As the feedback control, in addition to the proportional control (P control), an operation amount calculation algorithm that combines the integral control (I control) and / or the differential control (D control) can be adopted.
As a result, the bypass amount of the circulating water W1 with respect to the first heat dissipation heat exchanger 12A is adjusted, and the temperature of the liquid refrigerant R flowing into the expansion valve 13 is adjusted.
As a result of being bypassed, the refrigerant R that has not been condensed and liquefied in the first heat exchanger 12A is condensed and liquefied in the second heat exchanger 12B.

With the above configuration, even when the water source temperature of the make-up water is low, the temperature of the liquid refrigerant R flowing into the expansion valve 13 can be maintained at a constant temperature that does not cause a high supercooling state. Therefore, it is avoided that the liquid refrigerant R in the highly supercooled state is supplied to the endothermic heat exchanger 14, and the compressor 11 does not have an obstacle to suck the refrigerant R in the wet vapor state. This makes it possible to optimally operate the refrigeration cycle while preventing damage to the compressor 11.

Subsequently, a modified example of the fourth embodiment will be described with reference to the drawings. FIG. 8 is a diagram schematically showing a configuration of a hot water supply system according to a modified example of the fourth embodiment.

As shown in FIG. 8, the heat pump circuit 10 of this modification includes a refrigerant pressure sensor 17 that detects the pressure of the liquid refrigerant R flowing into the expansion valve 13, as in the modification of the first embodiment. Further, the control unit 100 of this modification includes a supercooling degree calculation unit 140 as in the modification of the first embodiment.

In this modification, the refrigerant pressure sensor 17, the refrigerant temperature sensor 16, the fourth bypass line L14, and the fourth distribution valve 34 constitute the refrigerant temperature adjusting means 50.

The distribution valve control unit 130 of the present embodiment controls the fourth distribution valve 34 based on the detection temperature of the refrigerant temperature sensor 16 and the detection pressure of the refrigerant pressure sensor 17. Specifically, the distribution valve control unit 130 of this modification controls the fourth distribution valve 34 so that the calculated supercooling degree calculated by the supercooling degree calculation unit 140 becomes the target supercooling degree, and the expansion valve 13 The degree of supercooling of the liquid refrigerant R flowing into the water is adjusted. Also in this case, the calculated supercooling degree calculated in real time by the supercooling degree calculation unit 140 is used as a feedback value, and the valve opening degree of the fourth distribution valve 34 is set so as to converge this calculated supercooling degree to the target supercooling degree. It is preferable to adopt a feedback control that adjusts.

In this way, the supercooling degree calculation unit 140 accurately calculates the supercooling degree of the liquid refrigerant R flowing into the expansion valve 13, and the distribution valve control unit 130 further calculates the calculated supercooling degree to be the target supercooling degree. By controlling the fourth distribution valve 34, the bypass amount of the make-up water W2 with respect to the first heat dissipation heat exchanger 12A is adjusted, and the cooling amount of the refrigerant R in the first heat dissipation heat exchanger 12A is suppressed. .. As a result, even when the water source temperature of the make-up water W2 is low, the temperature of the liquid refrigerant R flowing into the expansion valve 13 can be maintained at a constant temperature that does not cause a high supercooling state.

Also in this embodiment, the fourth distribution valve 34 is not limited to the mode provided in the fourth bypass line L14. For example, the fourth distribution valve 34 may be a three-way valve provided at a branch portion where the fourth bypass line L14 branches from the water circulation line L1.

According to the hot water supply system 1 of the fourth embodiment described above, in addition to (1), the following effects are obtained.

(8) The refrigerant temperature adjusting means 50 of the hot water supply system 1 of the present embodiment is connected to a temperature sensor 16 for detecting the temperature of the liquid refrigerant R flowing into the expansion valve 13 and a water circulation line L1 to exchange heat for first heat dissipation. The distribution amount of the fourth bypass line L14 for bypassing the circulating water W1 to the vessel 12A, the circulating water W1 to be fed to the first heat dissipation heat exchanger 12A, and the circulating water W1 to be fed to the fourth bypass line L14. A fourth distribution valve 34 for adjusting is provided, and the control means 100 controls the fourth distribution valve 34 so that the detection temperature of the temperature sensor 16 reaches the target temperature while the compressor 11 is being driven.
In this way, by controlling the fourth distribution valve 34 so that the detection temperature of the liquid refrigerant R flowing into the expansion valve 13 becomes the target temperature, the bypass amount of the circulating water W1 with respect to the first heat dissipation heat exchanger 12A can be increased. It is adjusted and the cooling amount of the refrigerant R in the first heat dissipation heat exchanger 12A is suppressed. As a result, even when the hot water storage temperature is set to a low temperature, the temperature of the liquid refrigerant R flowing into the expansion valve 13 can be maintained at a constant temperature that does not result in a high supercooling state.

(9) The refrigerant temperature adjusting means 50 of the hot water supply system 1 of the present embodiment detects the pressure of the temperature sensor 16 that detects the temperature of the liquid refrigerant R flowing into the expansion valve 13 and the pressure of the liquid refrigerant R flowing into the expansion valve 13. Circulation to supply to the fourth bypass line L14, which is connected to the water circulation line L1 and bypasses the circulating water W1 to the first heat dissipation heat exchanger 12A, and the first heat dissipation heat exchanger 12A. The control means 100 includes a fourth distribution valve 34 for adjusting the distribution amount of the circulating water W1 supplied to the water W1 and the fourth bypass line L14, and the control means 100 is based on the detected pressure of the pressure sensor 17 while the compressor 11 is being driven. The fourth is to obtain the condensation temperature of the gas refrigerant and to calculate the overcooling degree of the liquid refrigerant R by subtracting the detection temperature of the temperature sensor 16 from the condensation temperature so that the calculated overcooling degree becomes the target overcooling degree. Controls the distribution valve 34.
In this way, by controlling the fourth distribution valve 34 so that the calculated supercooling degree of the refrigerant R flowing into the expansion valve 13 becomes the target supercooling degree, the circulating water W1 with respect to the first heat dissipation heat exchanger 12A The bypass amount is adjusted, and the cooling amount of the refrigerant R in the first heat dissipation heat exchanger 12A is suppressed. As a result, even when the hot water storage temperature is set to a low temperature, the temperature of the liquid refrigerant R flowing into the expansion valve 13 can be maintained at a constant temperature that does not result in a high supercooling state.

Although the preferred embodiments of the hot water supply system of the present invention have been described above, the present invention is not limited to the above-described embodiments and can be appropriately modified. It is also possible to combine a plurality of embodiments.

1 Hot water supply system 10 Heat pump circuit 11 Compressor 12A First heat dissipation heat exchanger (condensor)
12B 2nd heat exchanger (supercooler)
13 Expansion valve 14 Endothermic heat exchanger (evaporator)
16 Refrigerant temperature sensor (temperature sensor)
17 Refrigerant pressure sensor (pressure sensor)
21 Water circulation pump 22 1st temperature sensor 25 Replenishment water valve 26 2nd temperature sensor 31 1st distribution valve 32 2nd distribution valve 33 3rd distribution valve 34 4th distribution valve 60 Hot water storage tank 61 Hot water storage temperature sensor 62 Water level sensor 100 Control unit (Control means)
110 Water circulation pump control unit 120 Replenishment water valve control unit 130 Distribution valve control unit 140 Overcooling degree calculation unit L1 Water circulation line L2 Replenishment water line L4 Hot water supply water line L9 Refrigerator circulation line L11 1st bypass line L12 2nd bypass line L13 3rd Bypass line L14 4th bypass line W1 Circulating water W2 Supplementary water W3 Reservoir water W4 Hot water supply water R Refrigerator (gas refrigerant, liquid refrigerant)

Claims (9)

1. The compressor, the first heat exchanger for heat dissipation, the second heat exchanger for heat dissipation, the expansion valve and the heat exchanger for heat absorption are connected in an annular shape by the refrigerant circulation line, and the heat exchange for the first heat dissipation is driven by the drive of the compressor. A steam compression type heat pump circuit that takes out heat from the device and / or the second heat exchanger for heat dissipation.
   A hot water storage tank that stores make-up water and
   A water circulation line that circulates the stored water in the hot water storage tank to the first heat exchanger for heat dissipation.
   A make-up water line that sends make-up water to the hot water storage tank while circulating make-up water to the second heat exchanger.
   A refrigerant temperature adjusting means for adjusting the temperature of the liquid refrigerant flowing into the expansion valve, and
   A hot water supply system including a control means for controlling the refrigerant temperature adjusting means.
2. The refrigerant temperature adjusting means is
   A temperature sensor that detects the temperature of the liquid refrigerant flowing into the expansion valve, and
   A first bypass line connected to the refrigerant circulation line and bypassing the refrigerant to the second heat exchanger for heat dissipation.
   A first distribution valve for adjusting the distribution amount of the refrigerant supplied to the second heat exchanger and the refrigerant supplied to the first bypass line is provided.
   The hot water supply system according to claim 1, wherein the control means controls the first distribution valve so that the temperature detected by the temperature sensor reaches a target temperature while the compressor is being driven.
3. The refrigerant temperature adjusting means is
   A temperature sensor that detects the temperature of the liquid refrigerant flowing into the expansion valve, and
   A pressure sensor that detects the pressure of the liquid refrigerant flowing into the expansion valve,
   A first bypass line connected to the refrigerant circulation line and bypassing the refrigerant to the second heat exchanger for heat dissipation.
   A first distribution valve for adjusting the distribution amount of the refrigerant supplied to the second heat exchanger and the refrigerant supplied to the first bypass line is provided.
   While the compressor is being driven, the control means obtains the condensation temperature of the gas refrigerant from the detection pressure of the pressure sensor, and subtracts the detection temperature of the temperature sensor from the condensation temperature to calculate the degree of supercooling of the liquid refrigerant. The hot water supply system according to claim 1, wherein the first distribution valve is controlled so that the calculated supercooling degree becomes the target supercooling degree.
4. The refrigerant temperature adjusting means is
   A temperature sensor that detects the temperature of the liquid refrigerant flowing into the expansion valve, and
   A second bypass line connected to the make-up water line and bypassing the make-up water to the second heat exchanger for heat dissipation.
   A second distribution valve for adjusting the distribution amount of the make-up water to be supplied to the second heat dissipation heat exchanger and the make-up water to be supplied to the second bypass line is provided.
   The hot water supply system according to claim 1, wherein the control means controls the second distribution valve so that the temperature detected by the temperature sensor reaches a target temperature while the compressor is being driven.
5. The refrigerant temperature adjusting means is
   A temperature sensor that detects the temperature of the liquid refrigerant flowing into the expansion valve, and
   A pressure sensor that detects the pressure of the liquid refrigerant flowing into the expansion valve,
   A second bypass line connected to the make-up water line and bypassing the make-up water to the second heat exchanger for heat dissipation.
   A second distribution valve for adjusting the distribution amount of the make-up water to be supplied to the second heat dissipation heat exchanger and the make-up water to be supplied to the second bypass line is provided.
   While the compressor is being driven, the control means obtains the condensation temperature of the gas refrigerant from the detection pressure of the pressure sensor, and subtracts the detection temperature of the temperature sensor from the condensation temperature to calculate the degree of supercooling of the liquid refrigerant. The hot water supply system according to claim 1, wherein the second distribution valve is controlled so that the calculated supercooling degree becomes the target supercooling degree.
6. The refrigerant temperature adjusting means is
   A temperature sensor that detects the temperature of the liquid refrigerant flowing into the expansion valve, and
   A third bypass line connected to the refrigerant circulation line and bypassing the refrigerant to the first heat exchanger for heat dissipation.
   A third distribution valve for adjusting the distribution amount of the refrigerant supplied to the first heat exchanger and the refrigerant supplied to the third bypass line is provided.
   The hot water supply system according to claim 1, wherein the control means controls the third distribution valve so that the temperature detected by the temperature sensor reaches a target temperature while the compressor is being driven.
7. The refrigerant temperature adjusting means is
   A temperature sensor that detects the temperature of the liquid refrigerant flowing into the expansion valve, and
   A pressure sensor that detects the pressure of the liquid refrigerant flowing into the expansion valve,
   A third bypass line connected to the refrigerant circulation line and bypassing the refrigerant to the first heat exchanger for heat dissipation.
   A third distribution valve for adjusting the distribution amount of the refrigerant supplied to the first heat exchanger and the refrigerant supplied to the third bypass line is provided.
   While the compressor is being driven, the control means obtains the condensation temperature of the gas refrigerant from the detection pressure of the pressure sensor, and subtracts the detection temperature of the temperature sensor from the condensation temperature to calculate the degree of supercooling of the liquid refrigerant. The hot water supply system according to claim 1, wherein the third distribution valve is controlled so that the calculated supercooling degree becomes the target supercooling degree.
8. The refrigerant temperature adjusting means is
   A temperature sensor that detects the temperature of the liquid refrigerant flowing into the expansion valve, and
   A fourth bypass line connected to the water circulation line and bypassing the circulating water to the first heat exchanger for heat dissipation.
   A fourth distribution valve for adjusting the distribution amount of the circulating water supplied to the first heat dissipation heat exchanger and the circulating water supplied to the fourth bypass line is provided.
   The hot water supply system according to claim 1, wherein the control means controls the fourth distribution valve so that the temperature detected by the temperature sensor reaches a target temperature while the compressor is being driven.
9. The refrigerant temperature adjusting means is
   A temperature sensor that detects the temperature of the liquid refrigerant flowing into the expansion valve, and
   A pressure sensor that detects the pressure of the liquid refrigerant flowing into the expansion valve,
   A fourth bypass line connected to the water circulation line and bypassing the circulating water to the first heat exchanger for heat dissipation.
   A fourth distribution valve for adjusting the distribution amount of the circulating water supplied to the first heat dissipation heat exchanger and the circulating water supplied to the fourth bypass line is provided.
   While the compressor is being driven, the control means obtains the condensation temperature of the gas refrigerant from the detection pressure of the pressure sensor, and subtracts the detection temperature of the temperature sensor from the condensation temperature to calculate the degree of supercooling of the liquid refrigerant. The hot water supply system according to claim 1, wherein the fourth distribution valve is controlled so that the calculated supercooling degree becomes the target supercooling degree.

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