JP2009092258A - Refrigeration cycle equipment - Google Patents

Abstract

The present invention relates to a refrigeration cycle apparatus, and an object thereof is to enable an energy-efficient operation regardless of the inflow temperature of a radiator heat receiving fluid and the inflow temperature of an evaporator heating fluid. .
At least a compressor 1, a radiator 2, a first decompression mechanism 3, a second decompression mechanism 5, and an evaporator 6 are sequentially connected to form a refrigeration cycle in which refrigerant circulates, and internal heat exchange is performed. In the decompression mechanisms (3, 5) on the upstream side and downstream side of the high-pressure side refrigerant flow path of the cooler 4, the opening degree of the decompression mechanism 3 on the upstream side is determined according to the inflow temperature of the radiator 2 heat receiving fluid and the evaporator 6 By controlling the heat fluid inflow temperature, etc., and optimizing the amount of heat exchange between the refrigerants in the internal heat exchanger 4, the inflow temperature of the radiator 2 heat receiving fluid, the inflow temperature of the evaporator 6 heating fluid, etc. Even so, energy efficient operation is possible.
[Selection] Figure 1

Description

  The present invention relates to a refrigeration cycle apparatus using a substance that can be supercritical on the high-pressure side as a refrigerant.

  Conventionally, this type of refrigeration cycle apparatus is typically used as a refrigeration cycle apparatus equipped with a heat pump water heater as shown in FIG.

  In FIG. 7, 51 is a compressor, 52 is a radiator, 54 is an expansion valve, and 55 is an evaporator. These are configured in an annular shape in this order to form a refrigerant circuit 56. In addition, the refrigerant circuit 56 includes an internal heat exchanger 53 that performs heat exchange between refrigerants between the high-pressure refrigerant supplied from the radiator 52 to the expansion valve 54 and the low-pressure refrigerant supplied from the evaporator 55 to the compressor 51. It has. The internal heat exchanger 53 is configured as shown in FIG. In FIG. 8, 81 is a high-pressure side refrigerant pipe, 82 is a low-pressure side refrigerant pipe, 83 is a branch pipe, and the internal heat exchanger 53 is located inside the low-pressure side refrigerant pipe 82 having a larger diameter than the low-pressure side refrigerant pipe 82. The double-pipe structure has a high-pressure side refrigerant pipe 81 with a small diameter, 84 is a high-pressure side refrigerant flow path, and 85 is a low-pressure side refrigerant flow path.

  Further, 11 is a hot water storage tank, 12 is a laminated pump, 13 is a three-way valve, and 14 is a hot water mixing valve. From the bottom of the hot water tank 11, the laminated pump 12, the radiator 2, and the three-way valve 13 are passed through the top of the hot water tank 11. A hot water supply circuit 16 that recirculates to the water is configured, and a hot water mixing valve 14 is provided in a mixing portion between the supply water pipe and the hot water supply pipe from the hot water storage tank 11.

  The operation of the refrigeration cycle apparatus equipped with the heat pump water heater configured as described above will be described below.

  The high-pressure refrigerant discharged from the compressor 51 is supplied to the radiator 52, and heat exchange is performed with water in the radiator 52, and the refrigerant whose temperature has decreased is supplied to the high-pressure side refrigerant flow path 84 of the internal heat exchanger 53. The In the internal heat exchanger 53, heat exchange is performed with the refrigerant flowing through the low-pressure side refrigerant flow path 85, and the heat is radiated and then supplied to the expansion valve 54. After being depressurized by the expansion valve 54, it is supplied to the evaporator 55 and absorbs heat, and then is sucked into the compressor 51 through the low-pressure side refrigerant passage 85 of the internal heat exchanger 53.

By the way, the amount of heat exchange in the internal heat exchanger 53 (hereinafter referred to as “internal heat exchange amount”) contributes to efficient use of a radiator (the above radiator), an evaporator, and the like. It is one of the important factors in development. In a conventional refrigeration cycle device, the amount of reduced pressure in the decompression mechanism (expansion valve) is controlled based on the discharge temperature and the calculated degree of suction superheat, thereby efficiently using a radiator, an evaporator, etc. A highly efficient refrigeration cycle apparatus has been realized (see, for example, Patent Document 1).
JP 2006-77998 A

However, the amount of internal heat exchange is determined by the heat transfer area, the inlet temperature of the high-pressure side refrigerant, and the inlet temperature of the low-pressure side refrigerant, and the operating conditions such as the inflow temperature of the radiator heat receiving fluid and the inflow temperature of the evaporator heating fluid change. However, the amount of internal heat exchange cannot be set to an optimum value according to these changes, and an operation with high energy efficiency can be performed only under specific conditions. For example, even if the internal heat exchanger is designed so that the internal heat exchange amount in the interim condition is the optimum value, the internal heat exchange amount cannot be made the optimum value in the winter condition or the summer condition. It was operating with low energy efficiency.

  So far, a refrigeration cycle apparatus that has improved energy efficiency by controlling the amount of internal heat exchange and efficiently operating the radiator and the evaporator has been proposed.

  For example, it is intended to increase the efficiency of the refrigeration cycle apparatus by providing decompression means on both the upstream side and the downstream side of the high-pressure side refrigerant flow path of the internal heat exchanger, and operating the evaporator efficiently. There is no mention of a control method for the two decompression means, and energy efficient operation cannot be maintained when operating conditions such as the inflow temperature of the radiator heat receiving fluid and the inflow temperature of the evaporator heating fluid change. It had the problem that.

  The present invention solves the above-mentioned problems, so that the internal heat exchange amount becomes an optimum value regardless of the inflow temperature of the radiator heat receiving fluid and the inflow temperature of the evaporator heating fluid. An object of the present invention is to provide a refrigeration cycle apparatus that controls two decompression mechanisms and can be operated with high energy efficiency.

  In order to achieve the above object, the present invention provides a decompression mechanism on each of the upstream side and the downstream side of the high-pressure side refrigerant flow path of the internal heat exchanger mounted in the refrigeration cycle apparatus, and the opening degree of the upstream side decompression mechanism. By controlling the internal heat exchange amount.

  According to the present invention, a pressure reducing mechanism is provided on each of the upstream side and the downstream side of the high-pressure side refrigerant flow path of the internal heat exchanger, and the opening degree of the upstream side pressure reducing mechanism is controlled, so that the amount of internal heat exchange is appropriately adjusted. Since the temperature can be adjusted, the refrigeration cycle apparatus can be operated with high energy efficiency regardless of the temperature of the heat receiving fluid heated in the radiator or the temperature of the heat receiving fluid cooled in the evaporator. The effect that can be obtained.

  In an embodiment of the present invention, at least the compressor, the radiator, the first decompression mechanism, the second decompression mechanism, and the evaporator are sequentially connected to form a refrigeration cycle in which the refrigerant circulates. In the refrigeration cycle apparatus comprising: an internal heat exchanger that exchanges heat between the refrigerant supplied from the decompression mechanism to the second decompression mechanism and the refrigerant supplied from the evaporator to the compressor; A heat receiving fluid inflow temperature detecting means for detecting the inflow temperature of the heat receiving fluid that exchanges heat with the refrigerant, and an inflow temperature of the evaporator heating fluid that detects the inflow temperature of the heating fluid that exchanges heat with the refrigerant in the evaporator Detection means, and the opening of the first pressure reducing mechanism is based on the temperature detected by the radiator heat receiving fluid inflow temperature detection means and the temperature detected by the evaporator heating fluid inflow temperature detection means. Characterized in that it is your. As a result, the internal heat exchange amount is appropriately controlled according to the temperature of the heat receiving fluid heated in the radiator and the temperature of the heat receiving fluid cooled in the evaporator, thereby making the refrigeration cycle apparatus highly efficient in various environments. There is an effect that you can drive.

  The opening of the first pressure reducing mechanism may be controlled based on a target outflow temperature of a heat receiving fluid that exchanges heat with a refrigerant in the radiator. By doing in this way, an internal heat exchange amount can be appropriately controlled according to the target outflow temperature of the heat receiving fluid in the radiator, and the refrigeration cycle apparatus can be operated with high energy efficiency.

Further, the opening degree of the first pressure reducing mechanism depends on the temperature of the heat receiving fluid heated in the radiator, the temperature of the heat receiving fluid cooled in the evaporator, and the target outflow of the heat receiving fluid that exchanges heat with the refrigerant in the radiator. It may be controlled based on temperature. By doing so, the refrigeration cycle apparatus can be operated with high energy efficiency by appropriately controlling the internal heat exchange amount in accordance with the target outflow temperature of the heat receiving fluid in the radiator in various environments.

  Moreover, the opening degree of the first pressure reducing mechanism may be controlled so as to decrease as the inflow temperature of the heat receiving fluid heated in the radiator increases. By doing in this way, internal heat exchange amount can be suppressed, so that the inflow temperature of heat receiving fluid is high, and a refrigerating cycle device can be operated with high energy efficiency.

  Moreover, the opening degree of the first pressure reducing mechanism may be controlled so as to become smaller as the inflow temperature of the heating fluid cooled in the evaporator is higher. By doing in this way, an internal heat exchange amount can be suppressed, so that the inflow temperature of a heating fluid is high, and a refrigerating-cycle apparatus can be drive | operated with high energy efficiency.

  Further, the opening degree of the first pressure reducing mechanism may be controlled by an internal heat exchange amount. By doing in this way, the amount of internal heat exchange can be controlled to a preset target value, and the refrigeration cycle apparatus can be operated with high energy efficiency.

The opening of the second pressure reducing mechanism may be controlled by the compressor discharge temperature. By doing in this way, the temperature of the refrigerant discharged from the compressor is controlled to a preset target value, and the refrigeration cycle apparatus can be operated with high energy efficiency.
The opening of the second pressure reducing mechanism may be controlled by the degree of superheat of the refrigerant sucked into the compressor. In this way, the refrigeration cycle apparatus can be operated with high energy efficiency by controlling the degree of superheat of the refrigerant sucked into the compressor to a preset target value.

Moreover, the structure which is not provided with a refrigerant | coolant storage device may be sufficient. By doing in this way, a refrigeration cycle apparatus can be made compact and the housing | casing to store can be reduced in size.
Further, a refrigerant that can be in a supercritical state on the high pressure side may be used as the refrigerant. By doing in this way, the high-pressure side refrigerant temperature can be increased, and the radiator heat receiving fluid can be efficiently heated.

  Carbon dioxide may be used as a refrigerant that can be in a supercritical state on the high-pressure side. By doing so, it is possible to remove the risk of ignition and explosion of the refrigerant.

  Hereinafter, a refrigeration cycle apparatus according to an embodiment of the present invention will be described with reference to the drawings. Although the embodiment will be described using a refrigeration cycle apparatus equipped with a heat pump water heater as an example, the embodiment of the present invention is not limited to a heat pump water heater, and may be an air conditioner or the like. .

(Embodiment 1)
First, the configuration of the refrigeration cycle in Embodiment 1 of the present invention will be described. A block diagram is shown in FIG. In FIG. 1, 1 is a compressor, 2 is a radiator (a radiator that uses water as a heat receiving fluid), 3 is a first expansion valve, 5 is a second expansion valve, and 6 is an evaporator (air is used as a heating fluid). 7 is a refrigerant circuit formed by connecting them in an annular shape. The refrigerant circuit 7 is an internal heat exchanger that performs heat exchange between refrigerants between the high-pressure refrigerant supplied from the radiator 2 to the expansion valve 5 and the low-pressure refrigerant supplied from the evaporator evaporator 6 to the compressor 1. 4 is provided.

Note that no refrigerant reservoir is provided in the refrigerant circuit 8. On the other hand, 11 is a hot water storage tank, 12 is a stacking pump, 13 is a three-way valve, 14 is a hot water mixing valve, 16 is a bottom of the hot water storage tank 11 and passes through the stacking pump 12, the radiator 2 and the three-way valve 13. A hot water supply circuit 16 is refluxed to the top of the tower. A refrigeration cycle apparatus in this embodiment (here, a refrigeration cycle apparatus mounted on a heat pump water heater) includes the refrigerant circuit 7 and the hot water supply circuit 16.

  Further, 21 is a discharge temperature detecting means, 22 is an incoming water temperature detecting means, 23 is an outside air temperature detecting means, 29 is a target hot water temperature determining means, 31 is a first expansion valve opening control device, and 32 is a second expansion valve. It is an opening degree control device.

Next, the operation and action of the refrigeration cycle apparatus configured as described above will be described. The refrigerant in the supercritical state, which has been heated and raised to a high temperature and a high pressure by the compressor 1, is cooled by exchanging heat with water circulating in the hot water supply circuit 16 in the radiator 2, and is then cooled by the intermediate pressure P in the first expansion valve 3. _{Depressurized} to _M. At this time, the opening degree of the first expansion valve 3 depends on the incoming water temperature T _W1 detected by the incoming water temperature detecting means 22, the outdoor air temperature T _air detected by the outdoor air temperature detecting means 23, and the target hot water temperature determining means 29. _Is determined by the first expansion valve opening degree control device 31 based on the target hot water temperature _TW2G determined in this way. The first expansion valve opening control device 31 has a table as shown in FIG. 2, and the opening of the first expansion valve 3 is smaller as the incoming water temperature is higher, the outdoor air temperature is higher and the target hot water temperature is higher. Control to make it smaller.

In order to adapt to changes in the incoming water temperature and the like, the process shown in FIG. 3 is performed at regular intervals (for example, 10 seconds). Refrigerant decompressed intermediate pressure P _M is after the low-pressure side refrigerant and the heat exchanger as a high-pressure side refrigerant in the internal heat exchanger 4, is reduced to a low pressure side pressure in the second expansion valve 5. At this time, the opening degree of the second expansion valve 5 is feedback controlled so that the discharge temperature Td detected by the discharge temperature detection means 21 by the second expansion valve opening degree control device 32 approaches the preset target value. Determined by. The decompressed low-pressure side refrigerant is heated by exchanging heat with the outside air in the evaporator 6 and then heated by exchanging heat with the high-pressure side refrigerant in the internal heat exchanger 4 and then sucked into the compressor 1. Is done. In the refrigeration cycle apparatus according to the present embodiment, a double pipe internal heat exchanger similar to the conventional example is used as the internal heat exchanger 4.

As described above, the pressure or temperature of the refrigerant supplied from the radiator 2 to the internal heat exchanger 4 is kept constant by controlling the opening degree of the first expansion valve 3 based on the incoming water temperature, the outside air temperature, and the target hot water temperature. Therefore, the internal heat exchange amount Q _IH can also be arbitrarily changed within a certain range. For example, if the opening degree of the first expansion valve 3 is increased, the intermediate pressure and the refrigerant temperature are increased and the internal heat exchange amount Q _IH is increased. However, if the opening degree is decreased, the intermediate pressure and the refrigerant temperature are decreased. The internal heat exchange amount Q _IH decreases.

  By doing so, it is possible to adjust the internal heat exchange amount without changing the heat transfer area used for heat exchange between refrigerants in the internal heat exchanger, such as the incoming water temperature, the outside air temperature, and the target hot water temperature. Even when the operating conditions of the refrigeration cycle apparatus change, the amount of internal heat exchange is controlled to operate the refrigeration cycle apparatus so that the operation with high energy efficiency is maintained.

  According to the present embodiment, with the above configuration, the first expansion valve and the second expansion valve are provided on the upstream side and the downstream side of the high-pressure refrigerant pipe of the internal heat exchanger, respectively, and the incoming water temperature, the outside air temperature, and the target hot water temperature By controlling the opening of the first expansion valve based on the temperature, the amount of internal heat exchange can be achieved without changing the heat transfer area in the internal heat exchanger even when the incoming water temperature, the outside air temperature, or the target hot water temperature changes. Therefore, it is possible to easily operate the refrigeration cycle apparatus with high energy efficiency at any incoming water temperature, outside air temperature, and target hot water temperature.

In the present embodiment, an internal heat exchanger having a double pipe structure including a high pressure side refrigerant pipe inside a low pressure side refrigerant pipe as shown in FIG. 8 is used. As long as the heat exchanger has a function of performing heat exchange with the side refrigerant, it may have any structure. For example, a structure in which the high-pressure side refrigerant pipe and the low-pressure side refrigerant pipe are arranged so as to contact each other on the side surface may be employed.

  Further, for example, if a refrigerant reservoir is provided between the evaporator 6 and the compressor 1, the refrigerant is stored in the refrigerant reservoir when the operating conditions of the refrigeration cycle apparatus such as the incoming water temperature, the outside air temperature, and the target hot water temperature change. It is possible to efficiently operate the radiator 2 and the evaporator 6 by adjusting the amount of refrigerant circulating through the refrigerant circuit 8 and maintain the operation with high energy efficiency. The refrigeration cycle apparatus in the embodiment realizes a refrigeration cycle apparatus having high energy efficiency at any incoming water temperature, outside air temperature, and target hot water temperature by controlling the amount of internal heat exchange without providing a refrigerant reservoir.

(Embodiment 2)
Below, the structure of the refrigerating-cycle apparatus in Embodiment 2 of this invention is described. A block diagram is shown in FIG. In FIG. 4, the refrigeration cycle apparatus in the present embodiment is configured in the same manner as in (Embodiment 1), 24 is an internal heat exchanger high pressure side inlet temperature detection means, and 25 is an internal heat exchanger high pressure side outlet temperature detection means. , 26 is an evaporator inlet temperature detecting means, 27 is an intake temperature detecting means, and 28 is an intermediate pressure detecting means.

Next, the operation and action of the refrigeration cycle apparatus configured as described above will be described. In the present embodiment, the control method of the first expansion valve 3 and the second expansion valve 5 is different from that of (Embodiment 1), but the other operations and actions are the same. Hereinafter, a method for controlling the two expansion valves will be described. In the refrigeration cycle apparatus in the present embodiment, the opening degree of the first expansion valve 3 is feedback-controlled so that the internal heat exchange amount Q _IH approaches the target value Q _IHG . The target internal heat exchange amount Q _IHG is determined by the incoming water temperature T _W1 as shown in FIG. 6, and the expansion valve opening is determined in accordance with the processing shown in FIG.

First, by the entering-water temperature detecting means 22 detects the incoming water temperature _{T W1,} to determine the target internal heat exchanging amount _{Q IHG} based on the detected incoming water temperature _{T W1.} Next, the evaporator inlet temperature detection means 26 detects the evaporation temperature T _sat , the suction temperature detection means 27 detects the suction temperature Ts, and circulates through the refrigerant circuit 7 from these, the rotational frequency of the compressor 1 and the compression chamber volume. The refrigerant circulation amount Gr to be calculated is calculated.

Thereafter, the first expansion valve opening degree control means 31 detects the intermediate pressure P _M detected by the intermediate pressure detection means 28, the internal heat exchanger high-pressure side inlet temperature T _IH1 detected by the internal heat exchanger high-pressure side inlet temperature detection means 24. Then, the internal heat exchange amount Q _IH is calculated from the internal heat exchanger high pressure side outlet temperature T _IH2 detected by the internal heat exchanger high pressure side outlet temperature detection means 25 and the refrigerant circulation amount Gr calculated in advance.

Further, by controlling the opening degree of the first expansion valve 3 as described above, the internal heat exchange amount _QIH can be arbitrarily determined with good controllability within a certain range. For example, when the internal heat exchange amount is excessive, the opening degree of the first expansion valve 3 is reduced to reduce the internal heat exchanger high-pressure side inlet temperature / pressure, thereby reducing the internal heat exchange amount Q _IH . When the internal heat exchange amount is too small, the internal heat exchange amount is increased by increasing the opening of the first expansion valve 3 and increasing the internal heat exchanger high-pressure side inlet temperature / pressure. The inter-interval amount Q _IH can be controlled so as to approach the target value.

Further, the opening degree of the second expansion valve 5 is determined by the second expansion valve opening degree control device 32, the evaporation temperature T _sat detected by the evaporator inlet temperature detection means 26, and the suction temperature Ts detected by the suction temperature detection means 27. Then, the degree of superheat of the refrigerant sucked into the compressor is calculated, and the calculated suction superheat degree is determined by feedback control so as to approach the preset target value.

  By doing so, it is possible to adjust the internal heat exchange amount without changing the heat transfer area used for heat exchange between refrigerants in the internal heat exchanger, such as the incoming water temperature, the outside air temperature, and the target hot water temperature. Even when the operating conditions of the refrigeration cycle apparatus change, the amount of internal heat exchange is controlled to operate the refrigeration cycle apparatus so that the operation with high energy efficiency is maintained.

  According to the present embodiment, with the above configuration, expansion valves are provided on the upstream side and the downstream side of the high-pressure side refrigerant pipe of the internal heat exchanger, and the internal heat exchange calculated from the temperature and pressure of each part of the refrigeration cycle apparatus By controlling the opening degree of the expansion valve provided on the upstream side based on the amount, the amount of internal heat exchange can be controlled even when the incoming water temperature, the outside air temperature, the target hot water temperature, or the like changes. The refrigeration cycle apparatus can be operated with high energy efficiency even at the incoming water temperature, the outside air temperature, and the target hot water temperature.

  Further, here, a refrigeration cycle apparatus that performs feedback control so that the degree of superheat calculated for the second expansion valve provided on the downstream side of the high-pressure side refrigerant pipe of the internal heat exchanger approaches a predetermined target degree of superheat. Although shown, even in the refrigeration cycle apparatus that detects the discharge temperature as described in (Embodiment 1) and controls the second expansion valve by feedback control so that the discharge temperature approaches the target discharge temperature, The effect can be obtained in the same manner without loss.

  The refrigeration cycle apparatus of the present invention operates with high energy efficiency by controlling the amount of internal heat exchange even when the inflow temperature of the radiator heat receiving fluid, the inflow temperature of the evaporator heating fluid, and the like change. This is useful for general refrigeration cycle apparatuses using a refrigerant that can be in a supercritical state on the high pressure side, such as a refrigeration cycle apparatus equipped with a heat pump water heater or a refrigeration cycle apparatus equipped with an air conditioner.

Configuration diagram of a refrigeration cycle apparatus equipped with a heat pump water heater in Embodiment 1 of the present invention The graph which shows the instruction | indication expansion valve opening degree which determines the opening degree of the said 1st expansion valve The flowchart which determines the opening degree of the first expansion valve Configuration diagram of a refrigeration cycle apparatus equipped with a heat pump water heater in Embodiment 2 of the present invention The flowchart which determines the opening degree of the 1st expansion valve in Embodiment 2 of this invention. A graph showing the amount of internal heat exchange instructed to determine the target internal heat exchange amount Configuration diagram of a conventional refrigeration cycle system equipped with a heat pump water heater (A) External view of internal heat exchanger used in the refrigeration cycle apparatus (b) Cross-sectional view of the internal heat exchanger used in the refrigeration cycle apparatus

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Compressor 2 Radiator 3 1st expansion valve 4 Internal heat exchanger 5 2nd expansion valve 6 Evaporator 7 Refrigerant circuit 11 Hot water storage tank 12 Laminated pump 13 Three-way valve 14 Hot-water supply mixing valve 15 Two-way valve 21 Discharge temperature detection means 22 Inlet water temperature detection means 23 Outside air temperature detection means 24 Internal heat exchanger high pressure side inlet temperature detection means 25 Internal heat exchanger high pressure side outlet temperature detection means 26 Evaporator inlet temperature detection means 27 Suction temperature detection means 28 Intermediate pressure detection means 29 Target Boiling temperature determining means 31 First expansion valve opening control device 32 Second expansion valve opening control device 41 Heat pump unit 42 Hot water storage unit 84 High-pressure side refrigerant flow path 85 Low-pressure side refrigerant flow path

Claims (12)

At least a compressor, a radiator, a first pressure reducing mechanism, a second pressure reducing mechanism, and an evaporator are sequentially connected to form a refrigeration cycle in which refrigerant circulates, and the first pressure reducing mechanism to the second pressure reducing mechanism. A liquid gas heat exchanger that exchanges heat between the supplied refrigerant and the refrigerant that is supplied from the evaporator to the compressor, and an inflow temperature of a heat receiving fluid that exchanges heat with the refrigerant in the radiator are detected. A first heat reducing fluid inflow temperature detecting means; and an evaporator heat receiving fluid inflow temperature detecting means for detecting an inflow temperature of the heating fluid that exchanges heat with the refrigerant in the evaporator; and an opening degree of the first pressure reducing mechanism. Is controlled based on the temperature detected by the radiator heat receiving fluid inflow temperature detecting means and the temperature detected by the evaporator heat receiving fluid inflow temperature detecting means. At least a compressor, a radiator, a first pressure reducing mechanism, a second pressure reducing mechanism, and an evaporator are sequentially connected to form a refrigeration cycle in which refrigerant circulates, and the first pressure reducing mechanism to the second pressure reducing mechanism. A liquid-gas heat exchanger that exchanges heat between the supplied refrigerant and the refrigerant supplied from the evaporator to the compressor, and the opening of the first decompression mechanism is configured so that A refrigeration cycle apparatus controlled based on a target outflow temperature of a heat receiving fluid to be exchanged. At least a compressor, a radiator, a first pressure reducing mechanism, a second pressure reducing mechanism, and an evaporator are sequentially connected to form a refrigeration cycle in which refrigerant circulates, and the first pressure reducing mechanism to the second pressure reducing mechanism. A liquid gas heat exchanger that exchanges heat between the supplied refrigerant and the refrigerant that is supplied from the evaporator to the compressor, and an inflow temperature of a heat receiving fluid that exchanges heat with the refrigerant in the radiator are detected. A first heat reducing fluid inflow temperature detecting means; and an evaporator heat receiving fluid inflow temperature detecting means for detecting an inflow temperature of the heating fluid that exchanges heat with the refrigerant in the evaporator; and an opening degree of the first pressure reducing mechanism. Are the temperature detected by the radiator heat receiving fluid inflow temperature detecting means, the temperature detected by the evaporator heat receiving fluid inflow temperature detecting means, and the target outflow temperature of the heat receiving fluid that exchanges heat with the refrigerant in the radiator. On the basis of the Refrigeration cycle apparatus characterized in that it is your. The opening degree of the first decompression mechanism is controlled so as to decrease as the inflow temperature of the heat receiving fluid detected by the heat receiving heat receiving fluid inflow temperature detecting means increases. Refrigeration cycle equipment. The opening degree of the first pressure reducing mechanism is controlled so as to decrease as the inflow temperature of the heating fluid detected by the evaporator heating fluid inflow temperature detection means increases. The refrigeration cycle apparatus described. 4. The refrigeration according to claim 2, wherein the opening degree of the first decompression mechanism is controlled to be smaller as the target outflow temperature of the heat receiving fluid that exchanges heat with the refrigerant in the radiator is higher. Cycle equipment. At least a compressor, a radiator, a first pressure reducing mechanism, a second pressure reducing mechanism, and an evaporator are sequentially connected to form a refrigeration cycle in which refrigerant circulates, and the first pressure reducing mechanism to the second pressure reducing mechanism. A liquid gas heat exchanger that exchanges heat between the supplied refrigerant and the refrigerant supplied from the evaporator to the compressor, and a heat exchange amount calculation that calculates the amount of heat exchanged in the liquid gas heat exchanger And a degree of opening of the first pressure reducing mechanism is controlled based on a heat exchange amount calculated by the heat exchange amount calculating means. Discharge temperature detection means for detecting the temperature of the refrigerant discharged from the compressor is provided, and the opening of the second pressure reducing mechanism is controlled based on the temperature detected by the discharge temperature detection means. The refrigeration cycle apparatus according to any one of claims 1 to 7. Superheating degree calculating means for calculating the superheat degree of the refrigerant supplied from the evaporator outlet or the refrigerant sucked into the compressor is provided, and the opening degree of the second pressure reducing mechanism is calculated by the superheat degree calculating means. The refrigeration cycle apparatus according to any one of claims 1 to 7, wherein the refrigeration cycle apparatus is controlled based on the degree of superheat. The refrigeration cycle apparatus according to any one of claims 1 to 9, wherein no refrigerant reservoir is provided. The refrigerant | coolant cycle apparatus of any one of Claims 1-10 using the refrigerant | coolant from which the refrigerant | coolant discharged from the said compressor can be in a supercritical state as a refrigerant | coolant. The refrigeration cycle apparatus according to claim 11, wherein carbon dioxide is used as the refrigerant.

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