JPH0593552A - Double stage compression type heat pump system - Google Patents

Abstract

PURPOSE:To realize a stable and high reliable operation by a method wherein a high temperature and a high capability at a load side heat exchanger are assured and an entire double stage compression heat pump system is operated in a high efficient manner. CONSTITUTION:A high pressure stage compressor mechanism 2 is controlled by a high stage pressure, a low pressure stage compressor mechanism 1 is controlled by an intermediate pressure, a main adjusting device 4 is controlled by a low pressure stage suction over-heating degree, a sub-adjusting device 7 is controlled by a high pressure stage suction over-heating degree, a hot water storing pump mechanism 12 is controlled by a hot water supplying water temperature, an auxiliary adjusting device 8b at an outlet side of a hot water supplying heat exchanger 3b is controlled by an amount of stored hot water and an auxiliary adjusting device 8a at an outlet port of an air conditioning heat exchanger 3a is controlled by a room temperature of a room where the indoor device is installed. With such an arrangement, it is possible to provide a double stage compression heat pump system capable of assuring a high temperature and a high capability at a load side heat exchanger and realizing an entire high efficient, stable and high reliable operation.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a two-stage compression heat pump system used for hot water supply, heating, etc.

[0002]

2. Description of the Related Art Conventionally, when a ratio of evaporation pressure to condensation pressure in a refrigerating cycle is large as in a low temperature refrigerating apparatus, a one-stage compressor is provided to prevent discharge temperature rise and improve efficiency of the compressor. A two-stage compression refrigeration cycle device in which two units are connected in series is used.

In this case, the gas discharged from the low-stage compressor is directly or indirectly exchanged with a high-pressure liquid refrigerant or an intermediate-pressure two-phase refrigerant to be cooled, and then sucked into the high-stage compressor. Then, it is compressed to a high pressure and discharged, and circulates in the cycle. By so doing, the intake gas temperature of the high-stage compressor is lowered and its discharge temperature is prevented from rising.

Further, by appropriately setting the ratio (compression ratio) between each suction pressure and each discharge pressure in the low-stage and high-stage compressors, the compressors in each stage can be operated under efficient conditions. As a whole, the refrigeration cycle efficiency is improved.

[0005]

However, in the above-mentioned conventional example, the conventional example is used only for a single function such as a low-temperature refrigerating apparatus, and is used for various purposes such as an air conditioner and hot water supply apparatus. There is almost no such proposal, and there is no proposal for a specific configuration including the operation method of the entire system for that purpose.

An object of the present invention is to provide a specific two-stage compression heat pump system that can be applied to a multipurpose device such as a cooling and heating hot water supply device and further includes a control method for the entire system. ..

[0007]

According to the present invention, a variable-frequency low-stage compression mechanism and a variable-frequency high-stage compression mechanism are connected in series, and a load side heat exchanger, a main expansion device, and a heat source side are connected to this. Refrigerant pair for connecting a heat exchanger to form a main refrigeration cycle and for exchanging heat between the low-stage refrigerant and the high-stage refrigerant, and the low-stage refrigerant inlet of the refrigerant heat exchanger, and the refrigerant pair via the auxiliary expansion device. The high-stage refrigerant inlet of the refrigerant heat exchanger is connected to the outlet of the load side heat exchanger, and the low-stage refrigerant outlet of the refrigerant-to-refrigerant heat exchanger is connected to the inlet of the heat source side heat exchanger via the main expansion device. Connected, the high-stage refrigerant outlet of the refrigerant-refrigerant heat exchanger is connected to the middle of the low-stage compression mechanism and the high-stage compression mechanism, and the refrigerant pressure in the load side heat exchanger is detected as the high stage pressure. The high-stage compression mechanism controller that controls the frequency of the high-stage compression mechanism so that it matches the high-stage pressure setting value, and the main throttle device The pressure of the refrigerant that has been decompressed by the low-stage compression mechanism is detected as the low-stage pressure, and the pressure of the refrigerant that has been decompressed by the sub-throttle device and the pressure of the refrigerant that has been compressed by the low-stage compression mechanism are detected as the intermediate pressure. This is provided with a low-stage side compression mechanism controller that controls the frequency of the low-stage side compression mechanism so as to match the geometric mean value of the high-stage pressure and the low-stage pressure.

Further, according to the present invention, the superheat degree of the refrigerant in the suction portion of the low-stage compression mechanism is detected as the low-stage suction superheat degree, and the low-stage suction superheat degree matches the low-stage suction superheat degree set value. The main throttle device controller for controlling the main throttle device is installed to detect the superheat degree of the refrigerant in the intake part of the high-stage compression mechanism as the high-stage intake superheat degree, and the high-stage intake superheat degree is high. It is provided with a sub-throttle device controller that controls the sub-throttle device so that the sub-throttle superheat degree setting value is matched.

Further, according to the present invention, the refrigerant inlets of a plurality of load side heat exchangers connected in parallel are connected to the discharge side of the high-stage compression mechanism, and a plurality of load side heat exchangers connected in parallel are connected. The refrigerant outlet of the heat exchanger is connected to the high-stage refrigerant inlet of the refrigerant-to-refrigerant heat exchanger and the auxiliary throttling device via a plurality of auxiliary throttling devices, respectively, and at least one of the plurality of load-side heat exchangers is supplied with hot water. A hot water supply unit is constructed by connecting a hot water storage tank, a hot water storage pump mechanism with variable flow rate, etc. as a heat exchanger for water, and detecting the temperature of the hot water supplied by the heat exchanger for hot water supply as the hot water temperature to supply hot water. It is equipped with a hot water pump mechanism controller that controls the hot water storage pump mechanism so that the water temperature matches the hot water supply water temperature set value. For hot water supply of multiple auxiliary expansion devices to match Equipped with exchangers auxiliary throttle device controller for hot water supply for controlling the connected auxiliary throttle device on the outlet side,
Furthermore, at least one of the multiple load side heat exchangers is used as an air conditioning heat exchanger to form an indoor unit with an indoor fan, etc., and the room temperature of the room in which the indoor unit is installed is detected to determine the room temperature. The auxiliary throttle device controller for air conditioning is provided to control the auxiliary throttle device connected to the outlet side of the heat exchanger for air conditioning among the plurality of auxiliary throttle devices so as to match the set value.

The refrigerant inlets of the plurality of load side heat exchangers are connected to the discharge side of the high-stage compression mechanism, and the refrigerant outlets of the plurality of load side heat exchangers connected in parallel are respectively connected to the plurality of refrigerant outlets. Connected to the high-stage refrigerant inlet of the refrigerant-to-refrigerant heat exchanger and the auxiliary expansion device via the auxiliary expansion device, and set the priority order among multiple load side heat exchangers and set multiple units according to the priority order. The auxiliary throttling device controller is provided for controlling the auxiliary throttling device.

[0011]

In the present invention, for example, the high-stage side compression mechanism is at a high-stage pressure, the low-stage side compression mechanism is at an intermediate pressure, the main throttle device is at a low-stage intake superheat degree, and the sub-throttle device is at a high-stage side intake pressure. The superheat degree, the hot water storage pump mechanism at the hot water temperature, the auxiliary expansion device at the outlet of the hot water supply heat exchanger at the hot water storage amount, and the auxiliary expansion device at the outlet of the air conditioning heat exchanger at room temperature in the room where the indoor unit is installed. By controlling with, the high temperature and high capacity of the load side heat exchanger can be secured, and highly efficient, stable, and reliable operation of the entire two-stage compression heat pump system can be realized.

[0012] In addition, if necessary, for example, hot water supply or air conditioning is prioritized by an auxiliary expansion device controller that preferentially circulates the refrigerant through one of a plurality of load side heat exchangers connected in parallel. It is possible to improve running time of hot water and air conditioning.

[0013]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 shows an embodiment in which the two-stage compression heat pump system of the present invention is used as an air conditioning hot water supply system.
FIG. 2 shows a control device in one embodiment in which the two-stage compression heat pump system of the present invention is used as an air conditioning hot water supply system. 1 is a variable frequency low-stage compression mechanism, 2 is a variable frequency high-stage compression mechanism, 3a is a load side heat exchanger used for air conditioning (hereinafter referred to as an air conditioning heat exchanger), 3b is a load used for hot water supply A side heat exchanger (hereinafter referred to as a hot water heat exchanger), 4 is a main expansion device, 5 is a heat source side heat exchanger, and a low-stage compression mechanism 1 and a high-stage compression mechanism in which these are connected in series The main refrigeration cycle is configured by connecting with 2. 6
Is a refrigerant-refrigerant heat exchanger for exchanging heat between the low-stage refrigerant and the high-stage refrigerant, and for the high-stage via the low-stage refrigerant inlet 6a of the refrigerant-refrigerant heat exchanger 6 and the auxiliary expansion device 7. The refrigerant inlet 6b is
It is connected to auxiliary expansion devices 8a and 8b on the outlet side of the load side heat exchangers 3a and 3b. The low-stage refrigerant outlet 6c of the refrigerant-to-refrigerant heat exchanger 6 is connected to the main expansion device 4, and the high-stage refrigerant outlet 6d is located at an intermediate confluence 6e of the low-stage side compression mechanism 1 and the high-stage side compression mechanism 2. Connected.

The air-conditioning heat exchanger 3a constitutes an indoor unit 9 together with an indoor fan (not shown) and is installed in the room 10. The hot water supply heat exchanger 3b constitutes a hot water supply unit 13 together with a hot water storage tank 11, a hot water storage pump mechanism 12 having a variable flow rate, and the like.

Numeral 14 indicates the refrigerant pressure from the high-stage compression mechanism 2 to the outlets of the load-side heat exchangers 3a and 3b, which is detected as a high-stage pressure and is set to a high value so as to match the high-stage pressure set value. A high-stage compression mechanism controller that controls the frequency of the high-stage compression mechanism 2, and 15 detects the refrigerant pressure reduced by the main expansion device 4 and sucked into the low-stage compression mechanism 1 as a low-stage pressure, Refrigerant decompressed by the auxiliary expansion device 7 and the low-stage compression mechanism 1
The low-stage side compression mechanism control for detecting the pressure of the refrigerant compressed as the intermediate pressure and controlling the frequency of the low-stage side compression mechanism 1 so that the intermediate pressure matches the geometric mean value of the high-stage pressure and the low-stage pressure. It is a vessel.

Reference numeral 16 detects the superheat degree of the refrigerant in the suction portion of the low-stage compression mechanism 1 as the low-stage suction superheat degree, and the low-stage suction superheat degree matches the low-stage suction superheat degree set value. A main throttle device controller for controlling the main throttle device 4 as described above,
Reference numeral 17 is a sub-detector for detecting the superheat degree of the refrigerant in the suction portion of the high-stage side compression mechanism 2 as the high-stage side intake superheat degree so that the high-stage side intake superheat degree matches the high-stage side intake superheat degree set value. Diaphragm device 7
It is a sub-throttle device controller for controlling.

Reference numeral 18 denotes a hot water storage pump mechanism 1 that detects the temperature of the hot water supplied by the hot water heat exchanger 3b as the hot water temperature and makes the hot water temperature match the hot water temperature set value.
2 is a hot water storage pump mechanism controller that controls the hot water supply heat exchanger 3 for detecting the amount of hot water stored in the hot water storage tank 11 as the hot water storage amount and matching the hot water storage amount with the hot water storage amount set value.
It is an auxiliary expansion device controller for hot water supply which controls an auxiliary expansion device 8b connected to the outlet side of b.

Reference numeral 20 denotes a room 1 in which the indoor unit 9 is installed.
The auxiliary throttle device controller for air conditioning controls the auxiliary throttle device 8a connected to the outlet side of the air conditioning heat exchanger 3a so that the room temperature of 0 is detected and the room temperature matches the room temperature set value.

Reference numeral 21 designates a priority order of a plurality of load side heat exchangers (in this embodiment, the air conditioning heat exchanger 3a and the hot water supply heat exchanger 3b) connected in parallel and set to the above priority order. It is an auxiliary expansion device controller that controls the plurality of auxiliary expansion devices 8a and 8b accordingly.

Next, the operation of the embodiment having the above configuration will be described. The refrigerant compressed and discharged from the high-stage compression mechanism 2 exchanges heat with the air in the room 10 in the air conditioning heat exchanger 3a or with the hot water supply water in the hot water supply heat exchanger 3b to give heat to be condensed and liquefied. At this time, the frequency of the high-stage compression mechanism 2 is set by the high-stage compression mechanism controller 14 so that the high-stage pressure (condensation pressure of the refrigerant in the air conditioning heat exchanger 3a or the hot water supply heat exchanger 3b) is high. Manipulated to match the value. Therefore, since the high-stage pressure is maintained at an appropriate pressure, it is possible to stably obtain a high temperature in the air conditioning heat exchanger 3a or the hot water supply heat exchanger 3b.

In this way, the refrigerant condensed and liquefied by applying heat to the object in the heat exchanger 3a for air conditioning or the heat exchanger 3b for hot water supply is condensed with the low-stage refrigerant before the auxiliary expansion device 7. It is branched to the stage refrigerant. Here, the high-stage refrigerant is decompressed by the auxiliary expansion device 7 to generate cold around, and then enters the refrigerant-to-refrigerant heat exchanger 6 through the high-stage refrigerant inlet 6b and exits through the high-stage refrigerant outlet 6d. .. On the other hand, the low-stage refrigerant enters the refrigerant-to-refrigerant heat exchanger 6 as it is from the low-stage refrigerant inlet 6a and exits from the low-stage refrigerant outlet 6c. Therefore, in the refrigerant-to-refrigerant heat exchanger 6, the low-stage refrigerant and the high-stage refrigerant that are decompressed and generate cold are heat-exchanged. As a result, the low-stage refrigerant is cooled and the degree of supercooling is increased, while the high-stage refrigerant is partially vaporized.

The low-stage refrigerant that has exited the refrigerant-refrigerant heat exchanger 6 is drawn into the low-stage compression mechanism 1 via the main expansion device 4 and the heat source side heat exchanger 5. At this time, in the main expansion device 4, the main expansion device controller 16 causes the refrigerant superheat degree (= low-stage intake superheat degree) in the suction portion of the low-stage compression mechanism 1 to match the low-stage intake superheat set value. To be operated. Therefore, since the low-stage suction superheat degree is appropriately maintained, it is possible to prevent the compression mechanism from being damaged by the liquid compression or to prevent the discharge refrigerant temperature of the low-stage compression mechanism 1 from rising, and the efficiency of the low-stage compression mechanism 1 is further improved. Will be improved. Also, the low-stage compression mechanism 1
By the low-stage compression mechanism controller 15, the discharge pressure (= intermediate pressure) of the low-stage compression mechanism 1 matches the geometric mean value of the suction pressure (= low-stage pressure) of the low-stage compression mechanism 1 and the high-stage pressure. To be operated. Therefore, since the compression ratios of the low-stage compression mechanism 1 and the high-stage compression mechanism 2 are appropriately maintained, the compression mechanism of each stage can be operated under efficient conditions.

In this way, the low-stage refrigerant compressed by the low-stage compression mechanism 1 reaches a high temperature, and the refrigerant-refrigerant heat exchanger 6
It merges with the partially vaporized high-stage refrigerant. Here, the low-stage refrigerant is cooled by the partially vaporized high-stage refrigerant, and then compressed by the high-stage compression mechanism 2. At this time, the sub expansion device 7 is superheated by the sub expansion device controller 17 at the suction portion of the high-stage compression mechanism 2 (= high-stage intake superheat).
Is operated so as to match the high-stage intake superheat setting value. Therefore, since the high-stage suction superheat degree is appropriately maintained, it is possible to prevent the compression mechanism from being damaged by the liquid compression or prevent the discharge refrigerant temperature of the high-stage compression mechanism 2 from rising, and the efficiency of the high-stage compression mechanism 2 is further improved. Will be improved.

Next, the hot water storage pump mechanism 12, the hot water storage pump mechanism controller 18, the auxiliary expansion devices 8a and 8b, the hot water supply auxiliary expansion device controller 19, the air conditioning auxiliary expansion device controller 20,
The auxiliary aperture device controller 21 will be described.

When the amount of hot water stored in the hot water storage tank 11 is reduced, the hot water supply auxiliary expansion device controller 19 operates the hot water supply auxiliary expansion device 8b to increase the flow rate of the refrigerant flowing in the hot water supply heat exchanger 3b. The heating capacity of the heat exchanger 3b is increased. On the other hand, the refrigerant pressure (= high stage pressure) in the hot water supply heat exchanger 3b is maintained at an appropriate pressure by the high stage side compression mechanism controller 14 and the high stage side compression mechanism 2, so the hot water storage pump mechanism controller 18 The temperature of the hot water supplied (the temperature of the hot water heated by the hot-water heat exchanger 3b) detected by the temperature rises. At this time, the hot water storage pump mechanism 12 increases the amount of hot water supplied by the hot water storage pump mechanism controller 18 to exchange heat with the refrigerant flowing through the hot water supply heat exchanger 3b so that the hot water supply water temperature matches the hot water supply water temperature set value. Therefore, it is possible to supply hot water having a predetermined high temperature in a short time.

When it is desired to heat the room 10 in which the indoor unit 9 is installed, the air conditioning auxiliary expansion device controller 20 operates the air conditioning auxiliary expansion device 8a to increase the flow rate of the refrigerant flowing through the air conditioning heat exchanger 3a. The heating capacity of the air-conditioning heat exchanger 3a is increased. On the other hand, since the refrigerant in the air conditioning heat exchanger 3a is maintained at an appropriate pressure (= high pressure setting value) by the high-stage compression mechanism controller 14 and the high-stage compression mechanism 2, the air conditioning heat exchanger 3a The room 10 can be heated in a short time by exchanging heat with the air in the room 10 by an indoor fan (not shown) and blowing out the hot air of the main residence into the room 10.

When the hot water supply load and the air conditioning load occur simultaneously, the auxiliary expansion device controller 21 operates.

First, when the air conditioning load and the hot water supply load are not prioritized, the auxiliary throttle device controller 21 supplies the hot water with each operation amount by the hot water supply auxiliary throttle device controller 19 and the air conditioning auxiliary throttle device controller 20. The auxiliary expansion device 8b and the air conditioning auxiliary expansion device 8a are operated.

Next, when the air conditioning load and the hot water supply load are prioritized, the case of preferentially performing hot water supply will be described. At this time, the auxiliary expansion device controller 21 determines whether the operation amount of the hot water supply auxiliary expansion device 8b by the hot water supply auxiliary expansion device controller 19 or the operation amount of the air conditioning auxiliary expansion device 8a by the air conditioning auxiliary expansion device controller 20. , Hot water supply auxiliary throttle device controller 19
By preferentially outputting the operation amount by the hot water supply expansion device 8b, it is possible to quickly cope with the hot water supply load. For example, the hot water supply auxiliary expansion device 8b is operated by an operation amount by the hot water supply auxiliary expansion device controller 19, and the air conditioning auxiliary expansion device 8a is operated by an operation amount smaller than the operation amount by the air conditioning auxiliary expansion device controller 20. This allows more refrigerant to be circulated preferentially through the hot water supply heat exchanger 3b to increase the heating capacity of the hot water supply heat exchanger 3b.

Similarly, when it is desired to preferentially perform air conditioning, the auxiliary throttle device controller 21 is the auxiliary throttle device controller 20 for air conditioning.
Among the operation amount of the auxiliary air conditioning expansion device 8a and the operation amount of the hot water supply auxiliary expansion device controller 19 by the hot water supply auxiliary expansion device controller 19, the operation amount by the air conditioning auxiliary expansion device controller 20 is preferentially given to the air conditioning expansion device. By outputting to the device 8a, it is possible to quickly cope with the air conditioning load.

In the above embodiment, two load side heat exchangers are connected in parallel, but the number of load side heat exchangers is not limited.

Each controller of the present invention may be realized by software using a computer, in addition to the circuit that exhibits those control functions.

[0034]

As described above, the two-stage compression heat pump system of the present invention ensures high temperature and high capacity in the load side heat exchanger, and the two-stage compression heat pump system is highly efficient and stable and reliable. It is possible to realize high driving performance.

Further, if necessary, for example, hot water supply or air conditioning of a certain room is controlled by an auxiliary expansion device controller which circulates the refrigerant preferentially in any of a plurality of load side heat exchangers connected in parallel. It has the advantage that priority can be given to improving hot water shortage and air conditioning start-up time.

[Brief description of drawings]

FIG. 1 is a configuration diagram of an embodiment of a two-stage compression heat pump system of the present invention.

FIG. 2 is a configuration diagram showing a control device in an embodiment using the two-stage compression heat pump system of the present invention as an air conditioning hot water supply system.

[Explanation of symbols]

1 Low-stage side compression mechanism 10 Room 2 High-stage side compression mechanism 11 Hot water storage tank 3a Air conditioning heat exchanger 12 Hot water storage pump mechanism 3b Hot water supply heat exchanger 13 Hot water storage unit 4 Main throttle device 14 High pressure side compression mechanism controller 5 Heat source Side heat exchanger 15 Low-stage compression mechanism controller 6 Refrigerant-to-refrigerant heat exchanger 16 Main throttle device controller 6a Low-stage refrigerant inlet 17 Secondary throttle device controller 6b High-stage refrigerant inlet 18 Hot water storage pump mechanism controller 6c Low-stage refrigerant outlet 19 Hot water supply auxiliary expansion device controller 6d High-stage refrigerant outlet 20 Air conditioning auxiliary expansion device controller 6e Intermediate confluence point 21 Auxiliary expansion device controller 7 Sub expansion device 8a, 8b Auxiliary expansion device 9 Indoor unit

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Minoru Tagashira 1006 Kadoma, Kadoma City, Osaka Prefecture Matsushita Electric Industrial Co., Ltd.

Claims (7)

[Claims] 1. A frequency variable low-stage compression mechanism and a frequency variable high-stage compression mechanism are connected in series, and a load side heat exchanger, a main expansion device, and a heat source side heat exchanger are connected to the main. A two-stage compression heat pump system constituting a refrigeration cycle, the low-stage refrigerant inlet of a refrigerant-to-refrigerant heat exchanger for exchanging heat between a low-stage refrigerant and a high-stage refrigerant, and the refrigerant through a sub expansion device. The high-stage refrigerant inlet of the refrigerant-to-refrigerant heat exchanger is connected to the outlet of the load-side heat exchanger, and the low-stage refrigerant outlet of the refrigerant-to-refrigerant heat exchanger is connected to the heat source side heat through the main expansion device. Connected to the inlet of the exchanger, the high-stage refrigerant outlet of the refrigerant-refrigerant heat exchanger is connected to the middle of the low-stage compression mechanism and the high-stage compression mechanism, and further compressed by the high-stage compression mechanism. The refrigerant pressure from the discharge side to the outlet of the load side heat exchanger is detected as a high-stage pressure. And a high-stage compression mechanism controller that controls the frequency of the high-stage compression mechanism so as to match the high-stage pressure set value, and the main throttle device reduces the pressure and sucks the low-stage compression mechanism. The refrigerant pressure is detected as a low-stage pressure, and the pressure of the refrigerant reduced by the sub-throttle device and the refrigerant compressed by the low-stage side compression mechanism is detected as an intermediate pressure, and the intermediate pressure is the high-stage pressure. A two-stage compression heat pump system comprising a low-stage compression mechanism controller that controls the frequency of the low-stage compression mechanism so as to substantially match the geometric mean value of the low-stage pressure. 2. The superheat degree of the refrigerant in the suction portion of the low-stage compression mechanism is detected as the low-stage suction superheat degree so that the low-stage suction superheat degree coincides with the low-stage suction superheat degree set value. The two-stage compression heat pump system according to claim 1, further comprising a main expansion device controller that controls the main expansion device. 3. The superheat degree of the refrigerant in the intake portion of the high-stage compression mechanism is detected as the high-stage intake superheat degree so that the high-stage intake superheat degree matches the high-stage intake superheat degree set value. The two-stage compression heat pump system according to claim 2, further comprising a sub expansion device controller that controls the sub expansion device. 4. The refrigerant inlets of a plurality of load side heat exchangers connected in parallel are connected to the discharge side of the high-stage side compression mechanism, and the plurality of load side heat exchangers connected in parallel are connected. Refrigerant outlets are respectively branched and connected to the high-stage refrigerant inlet of the refrigerant-to-refrigerant heat exchanger and the auxiliary throttle device via a plurality of auxiliary throttle devices, and at least one of the plurality of load-side heat exchangers One is used as a heat exchanger for hot water supply, and a hot water storage tank, a hot water storage pump mechanism with variable flow rate, etc. are connected to form a hot water supply unit, and the temperature of the hot water supplied by the heat exchanger for hot water supply is supplied as hot water. The two-stage compression heat pump according to claim 3, further comprising: a hot water storage pump mechanism controller that controls the hot water storage pump mechanism so that the hot water supply water temperature is detected as a water temperature and matches the hot water supply water temperature set value. system. 5. The hot water supply heat exchanger outlet of the plurality of auxiliary expansion devices is detected so that the amount of hot water stored in the hot water storage tank is detected as a hot water storage amount and the hot water storage amount matches the hot water storage amount set value. The two-stage compression heat pump system according to claim 4, further comprising a hot water supply auxiliary expansion device controller for controlling the connected auxiliary expansion device. 6. The refrigerant inlets of a plurality of load side heat exchangers connected in parallel are connected to the discharge side of the high-stage compression mechanism, and the plurality of load side heat exchangers connected in parallel are connected. Refrigerant outlets are respectively connected to the high-stage refrigerant inlet of the refrigerant-to-refrigerant heat exchanger and the sub-throttle device via a plurality of auxiliary expansion devices, and at least one of the plurality of load-side heat exchangers is It is used as a heat exchanger for air conditioning, constitutes an indoor unit together with an indoor fan, etc., and further detects the room temperature of the room in which the indoor unit is installed to detect the room temperature and match the room temperature with a set value of the plurality of units. The two-stage compression heat pump system according to claim 3, further comprising an air conditioning auxiliary expansion device controller that controls the auxiliary expansion device connected to the outlet of the air conditioning heat exchanger. 7. The refrigerant inlets of a plurality of load side heat exchangers connected in parallel are connected to the discharge side of the high-stage compression mechanism, and the plurality of load side heat exchangers connected in parallel are connected. Refrigerant outlets are connected to the high-stage refrigerant inlet of the refrigerant-to-refrigerant heat exchanger and the sub-throttle device via a plurality of auxiliary expansion devices, respectively, and priority is given to the plurality of load-side heat exchangers. 4. The two-stage compression heat pump system according to claim 3, further comprising: an auxiliary expansion device controller that controls the plurality of auxiliary expansion devices according to the priority order.