Control device, refrigeration cycle device, and air conditioner

Abstract

This control device controls a refrigeration cycle circuit comprising a main path in which a compressor, a condenser, a first decompression unit, and an evaporator are sequentially connected, a mixed refrigerant that circulates through the main path and includes a first refrigerant having the property of causing a disproportionation reaction and a second refrigerant having the property of not causing a disproportionation reaction, and a throttle part that adjusts at least one among the pressure and the flow rate of the mixed refrigerant, the control device comprising: an acquisition unit that acquires at least one among the suction pressure, discharge pressure, suction temperature, and discharge temperature of the compressor; a calculation unit that, on the basis of at least one among the suction pressure, discharge pressure, suction temperature, and discharge temperature, calculates at least one among disproportionation reactivity, which is an indicator for the mixed refrigerant to cause a disproportionation reaction, and a composition ratio of a first refrigerant included in the mixed refrigerant; and a control unit that controls the throttle part on the basis of the at least one among the disproportionation reactivity of the first refrigerant and the composition ratio of the first refrigeration calculated by the calculation unit.

Description

Control Device, Refrigeration Cycle Device, and Air Conditioning Device 【0001】 The present disclosure relates to a control device, a refrigeration cycle device, and an air conditioning device. 【0002】 For the purpose of reducing the environmental load of a refrigeration cycle device, it is required to apply a refrigerant with a low global warming potential (Global Warming Potential, hereinafter referred to as "GWP") (hereinafter referred to as "low GWP refrigerant") to the refrigerant used in the refrigeration cycle device. 【0003】 For example, in the case of Patent Document 1, a refrigeration cycle device capable of avoiding the disproportionation reaction in which the refrigerant causes a chain reaction is disclosed even when HFO-1123, which is a low GWP refrigerant, is used in the refrigeration cycle device. 【0004】 International Publication No. 2015 / 140870 【0005】 However, in the case of Patent Document 1, since the gas-liquid separator is connected to the main path, all the refrigerant circulating in the refrigeration cycle circuit passes through the gas-liquid separator. As a result, there is a problem that a pressure loss of the refrigerant in the gas-liquid separator occurs and the efficiency of the refrigeration cycle device is reduced. 【0006】 The present disclosure has been made to solve the above problems, and an object thereof is to provide a control device capable of reducing the risk of disproportionation reaction without reducing the efficiency even when applying a low GWP refrigerant that is likely to cause a disproportionation reaction. 【0007】The control device according to this disclosure controls a refrigeration cycle circuit comprising: a main path through which a compressor, a condenser, a first pressure reducing unit, and an evaporator are sequentially connected; a mixed refrigerant circulating in the main path and containing a first refrigerant having the property of causing a disproportionation reaction and a second refrigerant having the property of not causing a disproportionation reaction; and a throttle unit that adjusts at least one of the pressure and flow rate of the mixed refrigerant, comprising: an acquisition unit that acquires at least one of the suction pressure, discharge pressure, suction temperature, and discharge temperature of the compressor; a calculation unit that calculates at least one of the disproportionation reactivity of the mixed refrigerant, which is an indicator of whether the mixed refrigerant causes a disproportionation reaction, or the composition ratio of the first refrigerant contained in the mixed refrigerant, based on at least one of the suction pressure, discharge pressure, suction temperature, and discharge temperature; and a control unit that controls the throttle unit based on at least one of the disproportionation reactivity of the first refrigerant or the composition ratio of the first refrigerant calculated by the calculation unit. 【0008】 According to this disclosure, even when using a low GWP refrigerant, the risk of disproportionation reactions can be reduced without decreasing efficiency. 【0009】This is a schematic diagram showing a refrigeration cycle device according to Embodiment 1. This is a refrigerant circuit diagram showing a refrigeration cycle circuit according to Embodiment 1. This is a cross-sectional view showing an example of a compressor according to each embodiment. This is a circuit diagram showing a compressor drive device that drives the compressor. This is a front view showing an example of a condenser according to each embodiment. This is a partial cross-sectional view showing an example of a condenser or evaporator and a blower in a refrigeration cycle circuit according to each embodiment. This is a functional block diagram showing the configuration of a refrigeration cycle device according to Embodiment 1. This is a functional block diagram showing a processor and memory according to each embodiment. This is a functional block diagram showing a processing circuit according to each embodiment. This is a functional block diagram showing details of the disproportionation reactivity calculation unit according to Embodiment 1. This is a control flowchart of a refrigeration cycle device according to Embodiment 1. This is a refrigerant circuit diagram showing a refrigeration cycle circuit according to Embodiment 2. This is a refrigerant circuit diagram showing a refrigeration cycle circuit according to Embodiment 3. This is a refrigerant circuit diagram showing a refrigeration cycle circuit according to Embodiment 4. This is a refrigerant circuit diagram showing a refrigeration cycle circuit according to Embodiment 5. This is a functional block diagram showing the configuration of a refrigeration cycle device according to Embodiment 5. This is a control flowchart of a refrigeration cycle device according to Embodiment 5. This is a refrigerant circuit diagram showing a refrigeration cycle circuit according to Embodiment 6. This is a functional block diagram showing the configuration of a refrigeration cycle device according to Embodiment 6. This is a refrigerant circuit diagram showing a refrigeration cycle circuit according to Embodiment 7. This is a refrigerant circuit diagram showing another example of a refrigeration cycle circuit according to Embodiment 7. This is a refrigerant circuit diagram showing a refrigeration cycle circuit according to Embodiment 8. This is a functional block diagram showing the configuration of a refrigeration cycle device according to Embodiment 8. This is a refrigerant circuit diagram showing a refrigeration cycle circuit according to Embodiment 9. This is a refrigerant circuit diagram showing a refrigeration cycle circuit according to Embodiment 10. This is a front view showing an example of an air conditioning device according to each embodiment. 【0010】 Embodiments of the present invention will be described below with reference to the drawings. 【0011】Embodiment 1. <Configuration of the refrigeration cycle device according to Embodiment 1> Figure 1 is a schematic diagram showing the refrigeration cycle device 1 according to Embodiment 1. As shown in Figure 1, the refrigeration cycle device 1 according to Embodiment 1 comprises a refrigeration cycle circuit 2 and a system control unit 5. Figure 2 is a refrigerant circuit diagram showing the refrigeration cycle circuit 2 according to Embodiment 1. The refrigeration cycle circuit 2 according to Embodiment 1 is configured by sequentially connecting a compressor 10, a condenser 11, a first pressure reducing unit 13, and an evaporator 12 with refrigerant piping. A mixed refrigerant circulates in the refrigeration cycle circuit 2. In Figure 2, the arrows indicate the flow direction of the mixed refrigerant. 【0012】 The compressor 10 compresses the refrigerant it inhales and discharges it. The compressor 10 is, for example, a variable-speed type that can continuously adjust the refrigeration capacity, but it may also be a constant-speed type. 【0013】 Figure 3 is a cross-sectional view showing an example of a compressor 10 according to Embodiment 1. The compressor 10 is, for example, a rotary compressor. However, the compressor 10 according to Embodiment 1 is not limited to a rotary compressor, but may be other compressors such as a low-pressure compressor or a scroll compressor. 【0014】 As shown in Figure 3, the compressor 10 includes an electric motor 50, a crankshaft 51 as a rotating shaft, a compression mechanism 52, and a sealed container 53. The electric motor 50 drives the compression mechanism 52. The compression mechanism 52 compresses the mixed refrigerant drawn in from the accumulator 45. 【0015】 The crankshaft 51 connects the electric motor 50 and the compression mechanism 52. The crankshaft 51 has a shaft body portion 51a fixed to the rotor 50b of the electric motor 50 and an eccentric shaft portion 51b fixed to the rolling piston 60 of the compression mechanism 52. 【0016】 The sealed container 53 is cylindrical and houses the electric motor 50 and the compression mechanism 52. 【0017】The compressor 10 further includes an intake pipe 54, a discharge pipe 55, and a terminal 56, which are attached to the top of the sealed container 53. The intake pipe 54 guides the mixed refrigerant drawn in from outside the sealed container 53 to the compression mechanism 52. The discharge pipe 55 discharges the mixed refrigerant compressed by the compression mechanism 52 to the outside of the sealed container 53. The intake pipe 54 and the discharge pipe 55 are connected to the refrigeration cycle circuit 2 shown in Figure 2. 【0018】 Terminal 56 is connected to a compressor drive unit 140 located outside the compressor 10. Terminal 56 also supplies armature current Ia to the winding 50c of the stator 50a of the electric motor 50 via lead wire 57. This causes the rotor 50b of the electric motor 50 to rotate. 【0019】 Figure 4 is a circuit diagram showing a compressor drive device 140 that drives the compressor 10. As shown in Figure 4, the compressor drive device 140 includes a rectifier circuit 141 and an inverter 145. 【0020】 The rectifier circuit 141 includes bridge diodes 142a, 142b, 142c, 142d, a reactor 143, and a smoothing capacitor 144. The rectifier circuit 141 converts the AC voltage supplied from the AC power source into a DC voltage and outputs it. 【0021】 The inverter 145 has U-phase switching elements 146a, 146b, V-phase switching elements 146c, 146d, and W-phase switching elements 146e, 146f. Switching elements 146a and 146b are connected to the U-phase winding (not shown) of the motor 50. Switching elements 146c and 146d are connected to the V-phase winding (not shown) of the motor 50. Switching elements 146e and 146f are connected to the W-phase winding (not shown) of the motor 50. The inverter 145 converts the DC voltage output from the rectifier circuit 141 into AC voltage and outputs AC voltage to the U-phase, V-phase, and W-phase windings of the motor 50. As a result, an armature current Ia flows through winding 50c, causing the rotor 50b to rotate. In addition, an inverter current Ii flows between the smoothing capacitor 144 and the inverter 145. 【0022】The configuration of the condenser 11 will now be described. Figure 5 is a front view showing an example of a condenser 11 according to Embodiment 1. The condenser 11 according to Embodiment 1 is, for example, a heat exchanger. As shown in Figure 5, the condenser 11 according to Embodiment 1 comprises a header 101, heat transfer tubes 102, and fins 103. 【0023】 Multiple branched channels are formed in the header 101, and a heat transfer tube 102 is connected to each of the multiple branched channels. The header 101 is constructed using copper, aluminum, or carbon steel as the base material, which has excellent thermal conductivity. 【0024】 The heat transfer tube 102 is made of a hollow tube with a base material of copper, aluminum, or carbon steel, which has excellent thermal conductivity. The heat transfer tube 102 is connected to the header 101, and the mixed refrigerant branched off in the branched flow path of the header 101 flows through the heat transfer tube 102. Plate-shaped fins 103 are arranged in a row on the heat transfer tube 102. The shape of the heat transfer tube 102 may be, for example, a pipe with a circular cross-section (hereinafter: "circular pipe"), or a pipe with a rectangular cross-section with a large aspect ratio and rounded corners (hereinafter: "flat pipe"). 【0025】 The fins 103 are provided on the heat transfer tube 102 and are made of metal plates with excellent thermal conductivity, such as copper, aluminum, or carbon steel. The plate-shaped fins 103 are stacked at a constant pitch perpendicular to the axial direction of the heat transfer tube 102. 【0026】 Referring to Figure 2, the operation of the condenser 11 will be explained. The high-temperature, high-pressure mixed refrigerant sent from the compressor 10 flows to the inlet side of the condenser 11, and heat exchange with a medium (e.g., air, water, brine, etc.) takes place, causing the mixed refrigerant to condense and be sent out from the outlet side of the condenser as a low-temperature, high-pressure liquid refrigerant. Heat exchange with the medium occurs when the mixed refrigerant flows into the condenser 11 and the medium passes through the gaps between the fins 103 in a direction perpendicular to the axial direction of the heat transfer tubes 102. As a result, the amount of heat reduced by condensation in the mixed refrigerant is released to the outside of the condenser 11. 【0027】The first pressure reducing unit 13 can be, for example, an electronic expansion valve. The first pressure reducing unit 13 reduces the pressure of the refrigerant mixture passing through it and expands it to produce a low-temperature, low-pressure refrigerant mixture. The flow rate of the refrigerant mixture can be changed by adjusting the opening of the first pressure reducing unit 13. Specifically, increasing the opening of the first pressure reducing unit 13 increases the flow rate of the refrigerant mixture, and decreasing the opening of the first pressure reducing unit 13 decreases the flow rate of the refrigerant mixture. 【0028】 The evaporator 12 can use a heat exchanger of the same configuration as the condenser 11 shown in Figure 5. 【0029】 The operation of the evaporator 12 will now be explained. The low-temperature mixed refrigerant sent from the first pressure reduction unit 13 flows to the inlet side of the evaporator 12 and evaporates the mixed refrigerant through heat exchange with a medium (e.g., air, water, brine, etc.), and is sent out from the outlet side of the evaporator 12 as a high-temperature mixed refrigerant. Heat exchange with the medium occurs when the mixed refrigerant flows into the evaporator 12 and the medium passes through the gaps between the fins 103 in a direction perpendicular to the axial direction of the heat transfer tube 102. As a result, the outside of the evaporator 12 is cooled by the amount of heat added by the mixed refrigerant due to evaporation. 【0030】 Figure 6 is a partial cross-sectional view showing an example of a condenser 11 or evaporator 12 and a blower 110 in a refrigeration cycle circuit 2 according to Embodiment 1. As shown in Figure 6, the refrigeration cycle circuit 2 according to Embodiment 1 is provided with a blower 110 facing the condenser 11 or evaporator 12. 【0031】 The blower 110 consists of blades 111 and a blower motor 113. The blades 111 are connected to the blower shaft 112 of the blower motor 113, and by rotating the blower shaft 112 of the blower motor 113, the blades 111 rotate, generating airflow and blowing air. The blower motor 113 can be a synchronous motor or an induction motor. The blower 110 is installed in a position opposite the condenser 11 or evaporator 12, and the condenser 11 or evaporator 12 is located within the air passage of the blower 110. 【0032】The refrigeration cycle circuit 2 according to Embodiment 1 has either a pressure detection unit 58 for detecting the pressure of the mixed refrigerant in the compressor 10, or a temperature detection unit 59 for detecting the temperature of the mixed refrigerant in the compressor 10. Alternatively, it may have both the pressure detection unit 58 and the temperature detection unit 59. 【0033】 In the example shown in Figure 2, the pressure detection unit 58 and the temperature detection unit 59 are each provided on the discharge pipe 55 side of the compressor 10. In this case, the pressure detection unit 58 can detect the pressure of the mixed refrigerant discharged from the compressor 10 (hereinafter referred to as "discharge pressure Pd"), and the temperature detection unit 59 can detect the temperature of the mixed refrigerant discharged from the compressor 10 (hereinafter referred to as "discharge temperature Td"). Note that the positions of the pressure detection unit 58 and the temperature detection unit 59 are not limited to the example in Figure 2. For example, the pressure detection unit 58 and the temperature detection unit 59 may be provided inside the compressor 10 to detect the pressure and temperature inside the compressor 10. Alternatively, the pressure detection unit 58 and the temperature detection unit 59 may be provided upstream of the suction pipe 54 of the compressor 10 to detect the pressure of the refrigerant drawn into the compressor 10 (hereinafter referred to as "suction pressure Ps") and the temperature of the mixed refrigerant drawn into the compressor 10 (hereinafter referred to as "suction temperature Ts"). 【0034】 Furthermore, as shown in Figure 7, the refrigeration cycle device 1 according to Embodiment 1 may further include a current detection unit 70 that detects the armature current Ia flowing through the electric motor 50. In this case, the location where the current detection unit 70 is provided is not limited to the compressor 10, but can be provided in any part of the refrigeration cycle circuit 2 according to Embodiment 1, such as the inverter 145 of the compressor drive device 140. The current detection unit 70 may detect not only the armature current Ia but also the inverter current Ii. 【0035】 As shown in Figure 2, the refrigeration cycle circuit 2 according to Embodiment 1 further includes a main path 6 that sequentially connects a compressor 10, a condenser 11, a first pressure reducing unit 13, and an evaporator 12, a first branching unit 25, a first merging unit 20, a second merging unit 21, a gas-liquid separator 80, a first internal heat exchanger 85, and a first flow rate adjustment unit 15. 【0036】 The first branch section 25 is located between the discharge pipe 55 side of the compressor 10 and the inlet side of the condenser 11. 【0037】The first confluence section 20 is provided between the first branch section 25 and the inlet side of the condenser 11. 【0038】 The second confluence section 21 is provided between the outlet side of the evaporator 12 and the suction pipe 54 side of the compressor 10. 【0039】 The refrigeration cycle circuit 2 according to the first embodiment has a bypass path that branches from the path branched from the first branch section 25 and converges to the first confluence section 20 and the second confluence section 21. 【0040】 The gas-liquid separator 80 is provided on the bypass path, and a refrigerant inlet 80a, a gas refrigerant outlet 80b, and a liquid refrigerant outlet 80c are formed. Among the mixed refrigerant flowing in from the refrigerant inlet 80a, it is separated into a gas phase portion (gas refrigerant) and a liquid phase portion (liquid refrigerant) inside the gas-liquid separator 80. The gas refrigerant flows out from the gas refrigerant outlet 80b, and the liquid refrigerant flows out from the liquid refrigerant outlet 80c. 【0041】 A first bypass pipe 7 is provided between the first branch section 25 and the refrigerant inlet 80a of the gas-liquid separator 80. That is, the mixed refrigerant discharged from the compressor 10 is branched into a main path 6 and a first bypass pipe 7 at the first branch section 25. 【0042】 A second bypass pipe 7a is provided between the first confluence section 20 and the gas refrigerant outlet 80b of the gas-liquid separator 80. That is, the first confluence section 20 is where the mixed refrigerant flowing out from the first branch section 25 and flowing through the main path 6 and the gas refrigerant flowing out from the gas refrigerant outlet 80b of the gas-liquid separator 80 converge. 【0043】 A third bypass pipe 7b is provided between the liquid refrigerant outlet 80c of the gas-liquid separator 80 and the second confluence section 21. 【0044】 The first internal heat exchanger 85 is provided between the first branch section 25 and the refrigerant inlet 80a of the gas-liquid separator 80. Also, the first internal heat exchanger 85 is provided between the outlet side of the evaporator 12 and the suction pipe 54 side of the compressor 10. The first internal heat exchanger 85 performs heat exchange between the mixed refrigerant flowing out from the first branch section 25 and flowing through the first bypass pipe 7 and the mixed refrigerant flowing out from the evaporator 12. 【0045】The mixed refrigerant flowing out from the first branch portion 25 is condensed in the first internal heat exchanger 85 and flows into the refrigerant inlet 80a of the gas-liquid separator 80. Further, the mixed refrigerant flowing out from the evaporator 12 is evaporated in the first internal heat exchanger 85 and flows into the second confluence portion 21. 【0046】 As the first internal heat exchanger 85, for example, the same heat exchanger as the condenser 11 shown in FIG. 5 can be used. 【0047】 In FIG. 2, the gas-liquid separator 80 and the first internal heat exchanger 85 are provided separately, but the first internal heat exchanger 85 may be incorporated in the gas-liquid separator 80. 【0048】 As shown in FIG. 2, the refrigeration cycle circuit 2 according to the first embodiment is provided between the outlet side of the first internal heat exchanger 85 and the suction pipe 54 side of the compressor 10. Further, a first flow rate adjustment portion 15 for adjusting the flow rate of the mixed refrigerant is provided between the liquid refrigerant outlet 80c of the gas-liquid separator 80 and the second confluence portion 21. 【0049】 The first flow rate adjustment portion 15 according to the first embodiment is, for example, constituted by a valve. The first flow rate adjustment portion 15 is not limited to a valve and may be constituted by, for example, a capillary tube. 【0050】 The first flow rate adjustment portion 15 can change the flow rate of the liquid refrigerant passing through the inside by adjusting the opening degree. Specifically, by increasing the opening degree of the first flow rate adjustment portion 15, the flow rate of the mixed refrigerant is increased, and by decreasing the opening degree of the first flow rate adjustment portion 15, the flow rate of the mixed refrigerant is reduced. That is, the first flow rate adjustment portion 15 adjusts the flow rate of the liquid refrigerant flowing out from the liquid refrigerant outlet 80c of the gas-liquid separator 80. 【0051】 Among the liquid refrigerant flowing out from the liquid refrigerant outlet 80c of the gas-liquid separator 80, the liquid refrigerant whose flow rate is adjusted by the first flow rate adjustment portion 15 flows into the second confluence portion 21, and the remaining liquid refrigerant remains inside the gas-liquid separator 80. The liquid refrigerant flowing out from the second confluence portion 21 flows into the suction pipe 54 of the compressor 10. That is, by adjusting the flow rate of the liquid refrigerant by the first flow rate adjustment portion 15, the flow rate of the liquid refrigerant flowing into the suction pipe 54 of the compressor 10 can be adjusted. 【0052】The refrigeration cycle circuit 2 according to Embodiment 1 is filled with a mixed refrigerant containing a first refrigerant and a second refrigerant. The first refrigerant has the property of causing disproportionation reactions. The second refrigerant does not have the property of causing disproportionation reactions. In addition, the second refrigerant has a higher boiling point than the first refrigerant at the same pressure. 【0053】 Here, we will explain the disproportionation reaction of the mixed refrigerant. Normally, when compression of the mixed refrigerant begins in the compressor 10, the pressure of the mixed refrigerant increases, and the mixed refrigerant is discharged from the discharge pipe 55 of the compressor 10. The pressure of this discharged mixed refrigerant is the discharge pressure Pd. 【0054】 When the discharge pressure Pd increases due to compression of the refrigerant mixture, the refrigerant mixture containing substances that undergo disproportionation reactions generates heat of reaction. When this heat of reaction is transferred to surrounding refrigerant mixtures containing substances that undergo disproportionation reactions, those refrigerants also undergo disproportionation reactions. In other words, a chain reaction of disproportionation reactions causes a rapid volume expansion and temperature rise of the refrigerant mixture. 【0055】 Refrigerants that exhibit disproportionation properties include, for example, HFO-1123 (1,1,2-trifluoroethylene) or HFO-1132(e) ((e)-1,2-difluoroethylene). 【0056】 As an example, the disproportionation reaction of HFO-1123 can be represented by the following chemical reaction: CF2 = CHF → (1 / 2)CF4 + (3 / 2)C + HF + (heat of reaction) In this way, supplying energy to HFO-1123 can cause a disproportionation reaction of the mixed refrigerant, potentially generating heat of reaction. 【0057】 The first refrigerant in the mixed refrigerant according to Embodiment 1 is, for example, HFO-1123 (1,1,2-trifluoroethylene) or HFO-1132(e) ((e)-1,2-difluoroethylene). 【0058】The second refrigerant in the mixed refrigerant according to Embodiment 1 is, for example, R32, R1234yf, R290, or R152a. The second refrigerant is not limited to the above, and any refrigerant other than the first refrigerant, HFO-1123 (1,1,2-trifluoroethylene) or HFO-1132(e) ((e)-1,2-difluoroethylene), can constitute the second refrigerant. 【0059】 Figure 7 is a functional block diagram showing the configuration of the refrigeration cycle device 1 according to Embodiment 1. As shown in Figure 7, the refrigeration cycle device 1 according to Embodiment 1 has a system control unit 5. The system control unit 5 includes an acquisition unit 120, a composition ratio calculation unit 121, a disproportionation reaction calculation unit 122, a control unit 123, and a storage unit 124. 【0060】 The acquisition unit 120 acquires at least one piece of information: the pressure detected by the pressure detection unit 58, the temperature detected by the temperature detection unit 59, and the armature current Ia and inverter current Ii flowing through the inverter 145 detected by the current detection unit 70. The information to be acquired only needs to be one or more of either pressure or temperature. The pressure and temperature to be acquired are at least one of the suction pressure Ps, discharge pressure Pd, suction temperature Ts, and discharge temperature Td of the compressor 10. 【0061】 The composition ratio calculation unit 121 calculates the composition ratio of the first refrigerant contained in the mixed refrigerant inside the compressor 10 based on at least one of the pressure and temperature acquired by the acquisition unit 120, and at least one of the armature current Ia and inverter current Ii. The specific method for calculating the composition ratio will be described later. 【0062】 The disproportionation reactivity calculation unit 122 calculates the disproportionation reactivity A, which is an indicator of the disproportionation reaction that occurs in the mixed refrigerant, based on the temperature or pressure of the mixed refrigerant flowing through the refrigeration cycle circuit 2. The specific method for calculating the disproportionation reactivity A will be described later. 【0063】The control unit 123 controls the first flow rate adjustment unit 15 based on at least one of the suction pressure Ps, discharge pressure Pd, suction temperature Ts, and discharge temperature Td. Specifically, the control unit 123 controls the first flow rate adjustment unit 15 based on the disproportionation reactivity A of the first refrigerant calculated by the disproportionation reactivity calculation unit 122. More specifically, the control unit 123 controls the opening of the first flow rate adjustment unit 15 so that the disproportionation reactivity A of the first refrigerant is lower than the disproportionation reactivity threshold Ath, which is a threshold for the disproportionation reactivity A of the first refrigerant. Furthermore, if the disproportionation reactivity A of the first refrigerant calculated by the disproportionation reactivity calculation unit 122 is greater than or equal to the disproportionation reactivity threshold Ath, the control unit 123 increases the opening of the first flow rate adjustment unit 15. This adjusts the flow rate of the mixed refrigerant flowing through the refrigeration cycle circuit 2 and reduces the disproportionation reactivity A of the first refrigerant. 【0064】 The control unit 123 controls the first flow rate adjustment unit 15 based on the composition ratio of the first refrigerant calculated by the composition ratio calculation unit 121. Specifically, it controls the opening of the first flow rate adjustment unit 15 so that the composition ratio of the first refrigerant is lower than the composition ratio threshold, which is a threshold for the composition ratio of the first refrigerant. Furthermore, if the composition ratio of the first refrigerant calculated by the composition ratio calculation unit 121 is equal to or greater than the composition ratio threshold, the control unit 123 increases the opening of the first flow rate adjustment unit 15. This adjusts the flow rate of the mixed refrigerant flowing through the refrigeration cycle circuit 2 and reduces the composition ratio of the first refrigerant. 【0065】 The memory unit 124 stores information acquired by the acquisition unit 120, information on the disproportionation reactivity threshold Ath, information on the composition ratio threshold, and a table of polytropic indices for the compression process based on the composition ratio of the first refrigerant in the mixed refrigerant, which will be described later. 【0066】The system control unit 5, as shown in Figure 8, for example, consists of at least one processor 130 and at least one memory 131. The processor 130 is, for example, a CPU (Central Processing Unit) that executes programs stored in the memory 131. In this case, the functions of the control unit 123 and the storage unit 124 are realized by software, firmware, or a combination of software and firmware. The software and firmware can be stored as programs in the memory 131. With this configuration, the programs for realizing the functions of the system control unit 5 are executed by a computer. 【0067】 The memory 131 is a computer-readable recording medium, and is, for example, a volatile memory such as RAM (Random Access Memory) and ROM (Read Only Memory), a non-volatile memory, or a combination of volatile and non-volatile memory. 【0068】 The system control unit 5 may be composed of a dedicated hardware processing circuit 132, such as a single circuit or a composite circuit, as shown in Figure 9. In this case, the functions of the control unit 123 and the storage unit 124 are realized by the processing circuit 132. 【0069】 As shown in Figure 7, the control unit 123 according to Embodiment 1 controls the compressor drive device 140 that drives the compressor 10, the blower 110, and the first pressure reducing unit 13, in addition to the first flow rate adjustment unit 15. Alternatively, as in the control unit 123 according to Embodiment 1, one control unit 123 may control the compressor drive device 140, the blower 110, the first pressure reducing unit 13, and the first flow rate adjustment unit 15, or the compressor drive device 140, the blower 110, the first pressure reducing unit 13, and the first flow rate adjustment unit 15 may each be controlled by separate control units 123. 【0070】 The control unit 123 according to Embodiment 1 controls the rotational speed of the compressor 10 by controlling the frequency of the armature current Ia flowing through the stator 50a of the compressor 10. This controls the amount of refrigerant discharged by the compressor 10 per unit time. In other words, the capacity of the compressor 10 can be varied. 【0071】 The control unit 123 according to Embodiment 1 controls the rotation speed of the blower 110. This makes it possible to vary the amount of air generated from the blower 110. 【0072】 The control unit 123 according to Embodiment 1 controls the opening degree of the first pressure reduction unit 13. This makes it possible to change the pressure of the mixed refrigerant flowing through the main path 6 of the refrigeration cycle circuit 2. 【0073】 As described above, the mixed refrigerant according to Embodiment 1 includes a first refrigerant that has the property of undergoing a disproportionation reaction and a second refrigerant that does not undergo a disproportionation reaction. Since the second refrigerant does not undergo a disproportionation reaction even when it receives thermal energy, the chain reaction of the disproportionation reaction can be suppressed even when heat is transferred from the first refrigerant to the second refrigerant. For this reason, the mixed refrigerant of the first and second refrigerants is less prone to disproportionation reactions than a refrigerant composed of only the first refrigerant. Furthermore, in the mixed refrigerant of the first and second refrigerants, the lower the composition ratio of the first refrigerant, the lower the possibility of disproportionation reactions occurring in the mixed refrigerant. 【0074】 Furthermore, as mentioned above, the second refrigerant in the mixed refrigerant according to Embodiment 1 has a higher boiling point at the same pressure than the first refrigerant. As a result, the mixed refrigerant of the first and second refrigerants has the characteristic that, during the evaporation or condensation process, the gaseous side of the two-phase mixed refrigerant has a higher composition ratio of the first refrigerant, while the liquid side of the two-phase mixed refrigerant has a lower composition ratio of the first refrigerant. 【0075】 In the refrigeration cycle circuit 2, the inside of the compressor 10 becomes hot and high-pressure, making it the most likely place for a disproportionation reaction of the mixed refrigerant to occur. Furthermore, inside the compressor 10, frictional heat generated at the sliding parts (not shown) of the compression mechanism 52 is transferred to the mixed refrigerant. In addition, since the electrical path from terminal 56 to the motor 50 inside the compressor 10 is in the refrigerant atmosphere, electrical energy is transferred to the refrigerant due to short circuits or leakage currents in the electrical path. 【0076】Based on the above, the place in the refrigeration cycle circuit 2 where the mixed refrigerant is most likely to undergo a disproportionation reaction is inside the compressor 10. Therefore, in order to suppress the disproportionation reaction of the mixed refrigerant in the refrigeration cycle circuit 2, it is necessary to reduce the composition ratio of the first refrigerant in the mixed refrigerant present inside the compressor 10. To achieve this, it is effective to reduce the composition ratio of the first component of the mixed refrigerant flowing in from the suction pipe 54 of the compressor 10. 【0077】 <Operation of the refrigeration cycle circuit according to Embodiment 1> Next, the operation of the refrigeration cycle circuit 2 according to Embodiment 1 will be described. 【0078】 The mixed refrigerant, compressed to high temperature and pressure by the compressor 10, is discharged from the discharge pipe 55 of the compressor 10. As shown in Figure 2, the high-temperature, high-pressure mixed refrigerant discharged from the compressor 10 is distributed to two paths: the main path 6 and the first bypass pipe 7, which branch off from the first branch section 25. The mixed refrigerant that flows out of the first branch section 25 into the main path 6 flows into the condenser 11. The mixed refrigerant that flows out of the first branch section 25 into the first bypass pipe 7 flows into the first internal heat exchanger 85. 【0079】 First, let's explain the operation of the mixed refrigerant flowing from the first branch 25 into the main path 6. The high-temperature, high-pressure mixed refrigerant flowing into the condenser 11 undergoes heat exchange with an external medium (for example, air, water, brine, etc.) outside the refrigeration cycle circuit 2, and releases heat from the mixed refrigerant to become a low-temperature, high-pressure mixed refrigerant. 【0080】 Furthermore, in order to improve the fluidity of the medium outside the refrigeration cycle circuit 2, a blower 110 and a pump (not shown) may be placed facing the condenser 11, as shown in Figure 6. This promotes heat exchange in the condenser 11 and improves the efficiency of the refrigeration cycle circuit 2. 【0081】 The low-temperature, high-pressure mixed refrigerant that flows out of the condenser 11 flows into the first pressure reduction section 13, where it becomes a low-temperature, low-pressure mixed refrigerant. 【0082】The low-temperature, low-pressure mixed refrigerant that flows out from the first depressurization section 13 flows into the evaporator 12. The low-temperature, low-pressure mixed refrigerant that flows into the evaporator 12 undergoes heat exchange with a medium outside the refrigeration cycle circuit 2 (for example, air, water, brine, etc.), and absorbs heat from the mixed refrigerant to become a high-temperature, low-pressure mixed refrigerant. 【0083】 Furthermore, in order to improve the fluidity of the medium outside the refrigeration cycle circuit 2, a blower 110 or pump may be arranged facing the evaporator 12, as shown in Figure 6. This promotes heat exchange in the evaporator 12 and improves the efficiency of the refrigeration cycle circuit 2. 【0084】 The high-temperature, low-pressure mixed refrigerant that flows out of the evaporator 12 flows into the compressor 10. The high-temperature, low-pressure mixed refrigerant that flows into the compressor 10 is compressed and becomes a high-temperature, high-pressure mixed refrigerant again. 【0085】 As the above cycle is continuously repeated, thermal energy can be continuously transported from the external medium that has undergone heat exchange in the evaporator 12 to the external medium that has undergone heat exchange in the condenser 11. 【0086】 The condenser 11 and evaporator 12 are either the user-side heat exchanger or the heat source-side heat exchanger. For example, by placing a flow path switching device (e.g., a four-way valve) in the refrigeration cycle circuit, the user-side heat exchanger and the heat source-side heat exchanger can be swapped depending on the operating mode. 【0087】 Next, the operation of the mixed refrigerant flowing from the first branch section 25 into the first bypass piping 7 will be explained. The mixed refrigerant flowing from the first branch section 25 into the first bypass piping 7 flows into the first internal heat exchanger 85. The high-temperature, high-pressure mixed refrigerant flowing into the first internal heat exchanger 85 exchanges heat with the high-temperature, low-pressure mixed refrigerant drawn into the compressor 10, and condenses to become a high-pressure gas-liquid two-phase mixed refrigerant. 【0088】At this time, due to the difference in boiling points between the first and second refrigerants contained in the mixed refrigerant, the gaseous side of the two-phase mixed refrigerant has a higher composition ratio of the first refrigerant, while the liquid side has a lower composition ratio of the first refrigerant. The two-phase mixed refrigerant is separated into gaseous refrigerant and liquid refrigerant in the gas-liquid separator 80. The gaseous refrigerant with a high composition ratio of the first refrigerant flows out from the gaseous refrigerant outlet 80b of the gas-liquid separator 80 and flows into the first confluence section 20. 【0089】 The mixed refrigerant at the first confluence 20 has a higher proportion of the first refrigerant compared to the mixed refrigerant at the first branch 25. In other words, in the refrigeration cycle circuit 2 according to Embodiment 1, the condenser 11, the first pressure reducing unit 13, the evaporator 12, and each component up to the upstream side of the second confluence 21 that form the main path 6, as well as the mixed refrigerant in the refrigerant piping connecting them, have a high proportion of the first refrigerant. 【0090】 Generally, low-boiling-point mixed refrigerants have the effect of increasing the efficiency of refrigeration cycle equipment. Therefore, by increasing the composition ratio of the first refrigerant in the mixed refrigerant circulating in the main path 6, as in the refrigeration cycle circuit 2 according to Embodiment 1, the efficiency of the refrigeration cycle circuit 2 can be improved. 【0091】 On the other hand, the liquid refrigerant separated by the gas-liquid separator 80 has a low composition ratio of the first refrigerant. This liquid refrigerant is divided into liquid refrigerant that flows into the first flow rate adjustment unit 15 and liquid refrigerant that remains inside the gas-liquid separator 80. The amount of refrigerant flowing into the first flow rate adjustment unit 15 is adjusted by controlling the opening degree of the first flow rate adjustment unit 15 using the control unit 123. 【0092】 The liquid refrigerant flowing out from the first flow rate adjustment unit 15 flows into the second confluence unit 21. The mixed refrigerant flowing out from the second confluence unit 21 flows into the compressor 10. 【0093】 The composition ratio of the first refrigerant is reduced in the mixed refrigerant flowing into the compressor 10 as the liquid refrigerant flowing out from the first flow rate adjustment unit 15 flows into the second confluence unit 21. In other words, the composition ratio of the first refrigerant in the mixed refrigerant flowing into the suction pipe 54 of the compressor 10 is reduced, thereby lowering the composition ratio of the first refrigerant in the mixed refrigerant inside the compressor 10. As a result, it is possible to suppress the disproportionation reaction of the mixed refrigerant inside the compressor 10. 【0094】 Furthermore, the composition ratio of the first refrigerant in the mixed refrigerant inside the compressor 10 can also be controlled by adjusting the opening degree of the first pressure reduction unit 13. In this case, it is necessary to adjust the opening degree of the first pressure reduction unit 13 to change the amount of heat exchange in the first internal heat exchanger 85 and adjust the dryness of the mixed refrigerant that has become a gas-liquid two-phase state in the first internal heat exchanger 85. Since the first flow rate adjustment unit 15 has a higher control response to the first pressure reduction unit 13, if an abnormal temperature rise or pressure rise is detected in the compressor 10, the composition ratio of the first refrigerant in the mixed refrigerant inside the compressor 10 can be quickly reduced by adjusting the flow rate of the liquid refrigerant using the first flow rate adjustment unit 15. For the reasons described above, from the viewpoint of control responsiveness, it is desirable that the refrigeration cycle circuit 2 according to Embodiment 1 be provided with a first flow rate adjustment unit 15 and that the composition ratio of the first refrigerant be controlled by adjusting the opening degree of the first flow rate adjustment unit 15. 【0095】 As described above, the control unit 123 controls the compressor drive unit 140, the blower 110, the first pressure reducing unit 13, and the first flow rate adjustment unit 15. Specifically, the control unit 123 adjusts the rotational speed of the compressor 10, the rotational speed of the blower 110 and pumps arranged in relation to the condenser 11 and evaporator 12, and the opening degree of the first pressure reducing unit 13. This allows the refrigeration capacity of the refrigeration cycle circuit 2 to be controlled. 【0096】 In addition to the above, the control unit 123 according to Embodiment 1 adjusts the opening degree of the first flow rate adjustment unit 15. This allows control of the composition ratio of the mixed refrigerant inside the compressor 10 and the composition ratio of the first refrigerant contained in the mixed refrigerant. 【0097】 In the refrigeration cycle circuit 2 according to Embodiment 1, when the inside of the compressor 10 reaches a high temperature and high pressure state in which a disproportionation reaction of the mixed refrigerant is likely to occur, the control unit 123 adjusts the opening degree of the first flow rate adjustment unit 15 to adjust the composition ratio of the mixed refrigerant inside the compressor 10. 【0098】Alternatively, if an operating mode is implemented that is likely to cause a disproportionation reaction of the mixed refrigerant, such as a pump-down operation which is performed when removing the refrigeration cycle circuit 2, or if the composition ratio of the first refrigerant in the mixed refrigerant inside the compressor 10 changes, the control unit 123 adjusts the opening of the first flow rate adjustment unit 15 to control the composition ratio of the mixed refrigerant inside the compressor 10. 【0099】 As described above, the refrigeration cycle circuit 2 according to Embodiment 1 includes a pressure detection unit 58 that detects the pressure inside the compressor 10 and a temperature detection unit 59 that detects the temperature inside the compressor 10. 【0100】 The control unit 123 estimates whether the inside of the compressor 10 is in a high-temperature, high-pressure state where a disproportionation reaction of the mixed refrigerant is likely to occur, based on at least one of the pressure detected by the pressure detection unit 58 and the temperature detected by the temperature detection unit 59. Based on this estimation result, the control unit 123 controls the opening degree of the first flow rate adjustment unit 15 to control the composition ratio of the first refrigerant and the second refrigerant of the mixed refrigerant. 【0101】 As a means of estimating the internal state of the compressor 10, in addition to the pressure detection unit 58 and the temperature detection unit 59, a current detection unit 70 that detects the armature current Ia flowing through the motor 50 of the compressor 10 may also be provided. Since the discharge pressure Pd and compression ratio of the mixed refrigerant can be estimated based on the value of the armature current Ia of the motor 50, it can be estimated whether or not the inside of the compressor 10 is in a high-temperature, high-pressure state based on these estimated values. Note that the current detection unit 70 is not limited to the compressor 10, but may be provided in any of the refrigeration cycle circuits 2 according to Embodiment 1, for example, the inverter 145 of the compressor drive device 140. The current detection unit 70 may detect not only the armature current Ia but also the inverter current Ii. 【0102】 Furthermore, as a method for estimating the composition ratio of the first refrigerant in the mixed refrigerant inside the compressor 10 based on the pressure, temperature, and armature current Ia of the compressor 10, one method is to refer to a table of polytropic indices for the compression process based on the composition ratio of the first refrigerant in the mixed refrigerant, which is pre-set in the memory unit 124. 【0103】The above will be explained in detail. The compression process of the compressor 10 is considered a polytropic change, and the relationship between the discharge temperature Td [K] of the mixed refrigerant discharged from the compressor 10, the suction temperature Ts [K] of the mixed refrigerant drawn into the compressor 10, the discharge pressure Pd [MPa] of the mixed refrigerant discharged from the compressor 10, the suction pressure Ps [MPa] of the mixed refrigerant drawn into the compressor 10, and the polytropic index n is expressed by the following equation 1. 【0104】 【0105】 The polytropic index n differs depending on the type of refrigerant mixture. That is, the polytropic index n differs depending on the composition ratio of the first refrigerant and the second refrigerant in the refrigerant mixture inside the compressor 10. Furthermore, using Equation 1, the polytropic index n can be calculated by detecting the discharge temperature Td, suction temperature Ts, discharge pressure Pd, and suction pressure Ps of the refrigerant mixture using the pressure detection unit 58 and the temperature detection unit 59. The accuracy of calculating the polytropic index n can be improved by detecting at least one of the armature current Ia and inverter current Ii using the current detection unit 70. 【0106】 Therefore, by pre-setting a table of polytropic index n for the compression process based on the composition ratio of the first refrigerant in the mixed refrigerant in the storage unit 124, the composition ratio of the first refrigerant in the mixed refrigerant inside the compressor 10 can be estimated based on the calculated polytropic index n. 【0107】 Alternatively, the ambient temperature of the compressor 10 may be detected by a temperature sensor such as a thermistor, and the discharge temperature Td and suction temperature Ts of the mixed refrigerant may be corrected based on the detected ambient temperature. This improves the accuracy of calculating the polytropic index n and improves the accuracy of estimating the composition ratio of the first refrigerant in the mixed refrigerant inside the compressor 10. 【0108】Another method for estimating the composition ratio of the first refrigerant in the mixed refrigerant inside the compressor 10 is to estimate the composition of the first refrigerant in the mixed refrigerant in the refrigeration cycle circuit 2 that exists outside the path from the second junction 21, which includes the compressor 10, to the first branch 25, and then work backward from there to estimate the composition ratio of the first refrigerant in the mixed refrigerant inside the compressor 10. For example, by detecting the upstream and downstream temperatures of the first pressure reducing section 13 using a temperature sensor such as a thermistor, and detecting the temperature of the first internal heat exchanger 85, the composition of the first refrigerant in the mixed refrigerant in the main path 6 can be estimated. 【0109】 Furthermore, by providing a liquid level detection unit (not shown) in the gas-liquid separator 80, the composition of the first refrigerant in the liquid refrigerant can be estimated based on the detected liquid level. By obtaining the above information, the composition ratio of the first refrigerant in the mixed refrigerant inside the compressor 10 can be estimated. 【0110】 Next, a method for estimating the occurrence of a disproportionation reaction of the mixed refrigerant inside the compressor 10 will be described. Figure 10 is a functional block diagram showing the details of the disproportionation reactivity calculation unit 122 according to Embodiment 1. As shown in Figure 10, the disproportionation reactivity calculation unit 122 calculates the disproportionation reactivity A, which is an index of the disproportionation reaction of the mixed refrigerant, based on the composition ratio of the first refrigerant of the mixed refrigerant calculated by the composition ratio calculation unit 121 and at least one of the pressure, temperature, type, armature current Ia, and inverter current Ii of the mixed refrigerant flowing through the refrigeration cycle circuit 2. That is, the disproportionation reactivity A is calculated by combining or weighting the acquired information. For example, the accuracy of calculating the disproportionation reactivity A can be improved by increasing the weight of "pressure of the mixed refrigerant," "temperature of the mixed refrigerant," and "type of the mixed refrigerant," which have a particularly high correlation with the disproportionation reactivity A. 【0111】 The disproportionation reactivity calculation unit 122 can also calculate the disproportionation reactivity A based on the pressure, temperature, type, armature current Ia, and inverter current Ii of the mixed refrigerant flowing through the refrigeration cycle circuit 2, even without using the composition ratio of the first refrigerant of the mixed refrigerant calculated by the composition ratio calculation unit 121. 【0112】The disproportionation reactivity calculation unit 122 can also calculate the disproportionation reactivity A based solely on the composition ratio of the first refrigerant calculated by the composition ratio calculation unit 121. However, the accuracy of the calculation of the disproportionation reactivity A can be improved by calculating it based on the composition ratio of the first refrigerant and at least one of the following pieces of information acquired by the acquisition unit 120: the pressure of the mixed refrigerant, the temperature of the mixed refrigerant, the type of mixed refrigerant, and the armature current Ia flowing through the electric motor 50. 【0113】 As an example of a method for calculating the disproportionation reactivity A in the disproportionation reactivity calculation unit 122, for example, as shown in Figure 10, a table TB in which the composition ratio of the first refrigerant and the disproportionation reactivity A are associated may be stored in advance in the disproportionation reactivity calculation unit 122, and when the composition ratio of the first refrigerant is input to the disproportionation reactivity calculation unit 122, the disproportionation reactivity A may be calculated by referring to table TB. Alternatively, table TB in which the composition ratio of the first refrigerant and the disproportionation reactivity A are associated may be stored in advance in the storage unit 124. 【0114】 The information used to calculate the degree of disproportionation reactivity A is not limited to the above. For example, as shown in Figure 10, information such as the discharge temperature Td and discharge pressure Pd of the mixed refrigerant discharged from the discharge pipe 55 of the compressor 10, the temperature of the sealed container 53 of the compressor 10, the condensation temperature and condensation pressure when condensing in the condenser 11, the ambient temperature, and the type of refrigerant may be obtained, and the degree of disproportionation reactivity A may be calculated by combining or weighting the obtained information. 【0115】 Furthermore, when performing pump-down or defrosting operations, the refrigeration cycle is operated under high load conditions, which increases the pressure of the refrigerant mixture and makes disproportionation reactions more likely. Therefore, information such as whether or not pump-down operations and defrosting operations are performed may be acquired, and the degree of disproportionation reaction A may be calculated by combining or weighting the acquired information. 【0116】 Furthermore, for the discharge temperature Td, the temperature of the sealed container 53 of the compressor 10, and the condensation temperature, not only the absolute value of the temperature [°C] but also the rate of temperature increase [°C / sec] may be used as information. Similarly, for the discharge pressure Pd and the condensation pressure, not only the absolute value of the pressure [MPa] but also the rate of pressure increase [MPa / sec] may be used as information. 【0117】 <Control Flow of the Refrigeration Cycle Circuit According to Embodiment 1> The control flow of the refrigeration cycle circuit 2 according to Embodiment 1 will be described. Figure 11 is a control flowchart of the refrigeration cycle circuit 2 according to Embodiment 1. 【0118】 First, in step S100, the pressure detection unit 58 detects the suction pressure Ps or discharge pressure Pd of the compressor 10. Alternatively, the temperature detection unit 59 detects the suction temperature Ts or discharge temperature Td of the compressor 10. Alternatively, the current detection unit 70 detects at least one of the armature current Ia flowing through the motor 50 of the compressor 10 and the inverter current Ii flowing through the inverter 145. It is sufficient to detect one or more of either pressure or temperature. 【0119】 Next, in step S101, the pressure and temperature of the mixed refrigerant inside the compressor 10 are estimated based on at least one of the suction pressure Ps or discharge pressure Pd of the compressor 10 detected in step S100, the suction temperature Ts or discharge temperature Td of the compressor 10, and at least one of the armature current Ia and inverter current Ii. 【0120】 Next, in step S102, the composition ratio calculation unit 121 determines whether or not to estimate the composition ratio of the first refrigerant in the mixed refrigerant inside the compressor 10. If the composition ratio of the first refrigerant is to be estimated, the process proceeds to step S103. If the composition ratio of the first refrigerant is not to be estimated, the process proceeds to step S104. For example, when controlling the opening degree of the first flow rate adjustment unit 15 with high precision, by determining in step S102 that the composition ratio of the first refrigerant should be estimated, the degree of disproportionation reactivity A can be calculated based on information from both the composition ratio of the first refrigerant and the pressure and temperature inside the compressor 10. This improves the accuracy of the calculation of the degree of disproportionation reactivity A, and allows for high-precision control of the opening degree of the first flow rate adjustment unit 15. Furthermore, when quickly controlling the opening degree of the first flow rate adjustment unit 15, by determining in step S102 that the composition ratio of the first refrigerant is not to be estimated, the degree of disproportionation reactivity A can be calculated based only on the pressure and temperature information inside the compressor 10. This reduces the computational load required to calculate the degree of disproportionation reactivity A due to not estimating the composition ratio of the first refrigerant, thereby improving the responsiveness of controlling the opening degree of the first flow rate adjustment unit 15. 【0121】 Next, in step S103, the composition ratio of the first refrigerant in the mixed refrigerant inside the compressor 10 is estimated based on the information of the suction pressure Ps or discharge pressure Pd of the compressor 10 detected in step S100, the suction temperature Ts or discharge temperature Td of the compressor 10, and at least one of the armature current Ia and inverter current Ii. That is, the composition ratio of the first refrigerant in the mixed refrigerant inside the compressor 10 is estimated. Note that step S101 may be executed after step S103, but executing step S101 first can improve the accuracy of the estimation of the composition ratio of the first refrigerant in step S103. Also, if it is determined in step S102 that the composition ratio of the first refrigerant does not need to be estimated, step S103 is not executed. Executing step S103 is not necessarily required, and it is possible to skip step S103 and not estimate the composition ratio of the first refrigerant in the mixed refrigerant inside the compressor 10. 【0122】 Next, in step S104, the disproportionation reactivity calculation unit 122 calculates the disproportionation reactivity A based on the pressure and temperature inside the compressor 10 estimated in step S101 and the composition ratio of the first refrigerant in the mixed refrigerant inside the compressor 10 estimated in step S103. The disproportionation reactivity A is an indicator of the disproportionation reaction that occurs in the mixed refrigerant. If the disproportionation reactivity calculation unit 122 determines that the composition ratio of the first refrigerant is not estimated in step S102 and does not execute step S103, it may calculate the disproportionation reactivity A based on the pressure and temperature inside the compressor 10 estimated in step S101. 【0123】 Next, in step S105, the disproportionation reactivity A calculated by the disproportionation reactivity calculation unit 122 is compared with the disproportionation reactivity threshold Ath. If A < Ath, it is estimated that the possibility of a disproportionation reaction of the mixed refrigerant is low, and the process proceeds to step S106. If A ≥ Ath, it is estimated that the possibility of a disproportionation reaction of the mixed refrigerant is high, and the process proceeds to step S107. 【0124】Next, in step S106, the control unit 123 controls the opening of the first flow rate adjustment unit 15 to be reduced. This increases the composition ratio of the first refrigerant in the mixed refrigerant flowing through the main path 6, thereby improving the efficiency of the refrigeration cycle circuit 2. 【0125】 Next, in step S107, the control unit 123 controls the opening of the first flow rate adjustment unit 15 to increase. This reduces the composition ratio of the first refrigerant in the mixed refrigerant flowing into the suction pipe 54 of the compressor 10, thereby suppressing the occurrence of a disproportionation reaction of the mixed refrigerant inside the compressor 10. 【0126】 <Effects of the Refrigeration Cycle Device According to Embodiment 1> The refrigeration cycle device 1 according to Embodiment 1 comprises a refrigeration cycle circuit 2 having a compressor 10, a condenser 11, a first pressure reducing unit 13, and an evaporator 12, a control unit 123, and a mixed refrigerant containing a first refrigerant and a second refrigerant. The control unit 123 controls the composition ratio of the first refrigerant in the mixed refrigerant flowing into the compressor 10. 【0127】 The refrigeration cycle circuit 2 according to Embodiment 1 reduces the composition ratio of the first refrigerant, which is prone to disproportionation reactions, among the mixed refrigerant drawn into the compressor 10. This makes it possible to suppress the occurrence of disproportionation reactions of the mixed refrigerant inside the compressor 10. 【0128】 Furthermore, the refrigeration cycle circuit 2 according to Embodiment 1 increases the composition ratio of the first refrigerant in the mixed refrigerant flowing through the main path 6. A mixed refrigerant with a low boiling point has the effect of increasing the efficiency of the refrigeration cycle device. Moreover, since only a portion of the mixed refrigerant circulating in the refrigeration cycle circuit 2 passes through the gas-liquid separator 80, the pressure loss of the mixed refrigerant in the gas-liquid separator 80 can be suppressed. This makes it possible to reduce the risk of disproportionation reaction without reducing efficiency. 【0129】 Embodiment 2. <Configuration and Operation of the Refrigeration Cycle Circuit According to Embodiment 2> The configuration and operation of the refrigeration cycle circuit 2a according to Embodiment 2 will be described. Matters common to Embodiment 1 will be omitted from the explanation, and matters that differ from Embodiment 1 will be described. 【0130】Figure 12 is a refrigerant circuit diagram showing a refrigeration cycle circuit 2a according to Embodiment 2. Compared to the refrigeration cycle circuit 2 according to Embodiment 1, the position of the second junction 21 in the refrigeration cycle circuit 2a according to Embodiment 2 is different. 【0131】 In the refrigeration cycle circuit 2 according to Embodiment 1, a second junction 21 was provided between the outlet side of the first internal heat exchanger 85 and the suction pipe 54 side of the compressor 10. However, in the refrigeration cycle circuit 2a according to Embodiment 2, a second junction 21 is provided between the outlet side of the evaporator 12 and the inlet side of the first internal heat exchanger 85. 【0132】 The operation of the refrigeration cycle circuit 2a according to Embodiment 2 will now be described. The liquid refrigerant flowing out from the liquid refrigerant outlet 80c of the gas-liquid separator 80 flows into the first flow rate adjustment unit 15. The liquid refrigerant flowing into the first flow rate adjustment unit 15 has its flow rate adjusted and flows into the third confluence unit 22. The mixed refrigerant flowing out from the third confluence unit 22 merges with the mixed refrigerant flowing out from the evaporator 12 to become a mixed refrigerant, which flows into the first internal heat exchanger 85. The mixed refrigerant flowing into the first internal heat exchanger 85 can increase the dryness of the mixed refrigerant by exchanging heat with the high-temperature, high-pressure mixed refrigerant flowing into the gas-liquid separator 80. 【0133】<Effects of the Refrigeration Cycle Circuit According to Embodiment 2> Compared with the refrigeration cycle circuit 2 according to Embodiment 1, the refrigeration cycle circuit 2a according to Embodiment 2 can increase the dryness of the mixed refrigerant that flows out of the gas-liquid separator 80 and into the compressor 10. That is, as the dryness of the mixed refrigerant increases, the weight ratio of liquid refrigerant contained in the mixed refrigerant is reduced, so the refrigeration cycle circuit 2a according to Embodiment 2 can reduce the amount of liquid refrigerant flowing into the compressor 10. If liquid compression occurs when the compressor 10 compresses the liquid refrigerant, liquid refrigerant may enter the compression mechanism 52, potentially causing the compressor 10 to malfunction. The refrigeration cycle circuit 2a according to Embodiment 2 can prevent liquid compression in the compression mechanism 52 of the compressor 10, thus increasing the reliability of the compressor 10. Also, similar to Embodiment 1, the refrigeration cycle circuit 2a according to Embodiment 2 increases the composition ratio of the first refrigerant in the mixed refrigerant flowing in the main path 6. Since a low boiling point mixed refrigerant has the effect of increasing the efficiency of the refrigeration cycle device, the efficiency of the refrigeration cycle circuit 2a can be improved. 【0134】 Embodiment 3. <Configuration and Operation of the Refrigeration Cycle Circuit According to Embodiment 3> The configuration and operation of the refrigeration cycle circuit 2b according to Embodiment 3 will be described. Matters common to Embodiment 1 will be omitted from the explanation, and matters that differ from Embodiment 1 will be described. 【0135】 Figure 13 is a refrigerant circuit diagram showing a refrigeration cycle circuit 2b according to Embodiment 3. The refrigeration cycle circuit 2b according to Embodiment 3 differs from the refrigeration cycle circuit 2 according to Embodiment 1 in that it is provided with a second internal heat exchanger 35. The refrigeration cycle circuit 2b includes a second internal heat exchanger 35 provided between the outlet side of the first flow rate adjustment unit 15 and the second confluence unit 21. 【0136】The operation of the refrigeration cycle circuit 2b according to Embodiment 3 will now be described. The liquid refrigerant flowing out from the liquid refrigerant outlet 80c of the gas-liquid separator 80 flows into the first flow rate adjustment unit 15. The liquid refrigerant flowing into the first flow rate adjustment unit 15 has its flow rate adjusted and flows into the second internal heat exchanger 35. The liquid refrigerant flowing into the second internal heat exchanger 35 becomes a gaseous refrigerant by exchanging heat with the high-temperature, high-pressure mixed refrigerant flowing into the gas-liquid separator 80. The gaseous refrigerant flowing out from the second internal heat exchanger 35 flows into the second confluence unit 21 and merges with the mixed refrigerant that flowed out from the evaporator 12 and underwent heat exchange in the first internal heat exchanger 85. The gaseous refrigerant flowing out from the second confluence unit 21 flows into the compressor 10. 【0137】 <Effects of the Refrigeration Cycle Circuit According to Embodiment 3> Compared with the refrigeration cycle circuit 2 according to Embodiment 1, the refrigeration cycle circuit 2b according to Embodiment 3 can increase the dryness of the mixed refrigerant flowing out of the gas-liquid separator 80 and into the compressor 10. That is, as the dryness of the mixed refrigerant increases, the weight ratio of liquid refrigerant contained in the mixed refrigerant decreases, so the refrigeration cycle circuit 2b according to Embodiment 3 can reduce the amount of liquid refrigerant flowing into the compressor 10. If liquid compression occurs when the compressor 10 compresses the liquid refrigerant, liquid refrigerant may enter the compression mechanism 52, potentially causing the compressor 10 to malfunction. The refrigeration cycle circuit 2b according to Embodiment 3 can prevent liquid compression in the compression mechanism 52 of the compressor 10, thus increasing the reliability of the compressor 10. In addition, since the high-temperature, high-pressure gaseous refrigerant flowing from the first branch 25 into the gas-liquid separator 80 can be cooled, the dryness of the mixed refrigerant inside the gas-liquid separator 80 can be reduced. As a result, the proportion of liquid refrigerant in the mixed refrigerant contained inside the gas-liquid separator 80 can be increased, making it easier to adjust the flow rate of liquid refrigerant flowing out from the liquid refrigerant outlet 80c of the gas-liquid separator 80 by the first flow rate adjustment unit 15, and improving the responsiveness of the control that changes the composition ratio of the first refrigerant in the mixed refrigerant. Also, similar to embodiments 1 and 2, the refrigeration cycle circuit 2b according to embodiment 3 increases the composition ratio of the first refrigerant in the mixed refrigerant flowing in the main path 6. Since a low boiling point refrigerant has the effect of increasing the efficiency of the refrigeration cycle device, the efficiency of the refrigeration cycle circuit 2b can be improved. 【0138】 Embodiment 4. <Configuration and Operation of the Refrigeration Cycle Circuit According to Embodiment 4> The configuration and operation of the refrigeration cycle circuit 2c according to Embodiment 4 will be described. Note that matters common to Embodiment 1 will be omitted from the explanation, and matters different from Embodiment 1 will be described. 【0139】 Figure 14 is a refrigerant circuit diagram showing a refrigeration cycle circuit 2c according to Embodiment 4. The refrigeration cycle circuit 2c according to Embodiment 4 differs from the refrigeration cycle circuit 2 according to Embodiment 1 in that a third internal heat exchanger 36 is provided. The refrigeration cycle circuit 2c includes a third internal heat exchanger 36 provided between the outlet side of the first internal heat exchanger 85 and the refrigerant inlet 80a of the gas-liquid separator 80. 【0140】 The operation of the refrigeration cycle circuit 2c according to Embodiment 4 will now be described. The high-temperature, high-pressure mixed refrigerant that flows into the first internal heat exchanger 85 exchanges heat with the high-temperature, low-pressure mixed refrigerant that flows out from the evaporator 12 and is drawn into the compressor 10 in the third internal heat exchanger 36, thereby becoming a high-pressure, two-phase mixed refrigerant that flows into the third internal heat exchanger 36. 【0141】 The mixed refrigerant flowing out of the first internal heat exchanger 85 flows into the third internal heat exchanger 36 and exchanges heat with the high-temperature, low-pressure mixed refrigerant flowing out of the evaporator 12. This results in a mixed refrigerant with a high degree of dryness. The mixed refrigerant flowing out of the third internal heat exchanger 36 flows into the gas-liquid separator 80. The liquid refrigerant flowing out of the liquid refrigerant outlet 80c of the gas-liquid separator 80 flows into the first flow rate adjustment unit 15. The liquid refrigerant flowing into the first flow rate adjustment unit 15 has its flow rate adjusted and flows into the second merging unit 21, where it merges with the mixed refrigerant that has undergone heat exchange in the first internal heat exchanger 85. The gaseous refrigerant flowing out of the second merging unit 21 flows into the compressor 10. 【0142】<Effects of the Refrigeration Cycle Circuit According to Embodiment 4> Compared with the refrigeration cycle circuit 2 according to Embodiment 1, the refrigeration cycle circuit 2c according to Embodiment 4 can increase the dryness of the mixed refrigerant that flows out of the gas-liquid separator 80 and into the compressor 10. That is, as the dryness of the mixed refrigerant increases, the weight ratio of liquid refrigerant contained in the refrigerant decreases, so the refrigeration cycle circuit 2c according to Embodiment 4 can reduce the amount of liquid refrigerant flowing into the compressor 10. If liquid compression occurs when the compressor 10 compresses the liquid refrigerant, liquid refrigerant may enter the compression mechanism 52, potentially causing the compressor 10 to malfunction. The refrigeration cycle circuit 2c according to Embodiment 4 can prevent liquid compression in the compression mechanism 52 of the compressor 10, thus increasing the reliability of the compressor 10. Also, similar to Embodiments 1-3, the refrigeration cycle circuit 2c according to Embodiment 4 increases the composition ratio of the first refrigerant in the mixed refrigerant flowing in the main path 6. Since a low boiling point mixed refrigerant has the effect of increasing the efficiency of the refrigeration cycle device, the efficiency of the refrigeration cycle circuit 2c can be improved. 【0143】 Embodiment 5. <Configuration and Operation of the Refrigeration Cycle Circuit According to Embodiment 5> The configuration and operation of the refrigeration cycle circuit 2d according to Embodiment 5 will be described. Note that matters common to Embodiment 1 will be omitted from the explanation, and matters different from Embodiment 1 will be described. 【0144】 Figure 15 is a refrigerant circuit diagram showing a refrigeration cycle circuit 2d according to Embodiment 5. Compared to the refrigeration cycle circuit 2 according to Embodiment 1, the refrigeration cycle circuit 2d according to Embodiment 5 includes a second branch section 26, a third junction section 22, a fourth bypass pipe 7c, and a second flow rate adjustment section 30 in the bypass path. 【0145】 The second branch section 26 is located between the outlet side of the evaporator 12 and the inlet side of the first internal heat exchanger 85. The second branch section 26 branches into the main path 6 and the fourth bypass pipe 7c, which will be described later. 【0146】 The third junction 22 is located between the outlet side of the first internal heat exchanger 85 and the second junction 21. The third junction 22 is where the main path 6 and the fourth bypass piping 7c, which will be described later, merge. 【0147】 The fourth bypass pipe 7c is installed between the second branch section 26 and the third junction section 22. 【0148】 The second flow rate adjustment unit 30 is provided between the second branching unit 26 and the inlet side of the first internal heat exchanger 85. 【0149】 The operation of the refrigeration cycle circuit 2d according to Embodiment 5 will now be described. The mixed refrigerant flowing out from the evaporator 12 flows into the second branching section 26. The mixed refrigerant flowing out from the second branching section 26 is branched into a mixed refrigerant that flows into the second flow rate adjustment section 30 and a mixed refrigerant that flows into the fourth bypass pipe 7c. 【0150】 The mixed refrigerant flowing into the second flow rate adjustment unit 30 has its flow rate adjusted by the control unit 123 controlling the opening of the second flow rate adjustment unit 30. The adjusted-flow-rate mixed refrigerant flows into the first internal heat exchanger 85 and exchanges heat with the mixed refrigerant flowing into the first internal heat exchanger 85 from the first branching unit 25. The mixed refrigerant flowing out of the first internal heat exchanger 85 flows into the third junction 22 and merges with the mixed refrigerant flowing into the fourth bypass piping 7c from the second branching unit 26. The mixed refrigerant flowing out of the third junction 22 flows into the second junction 21 and merges with the liquid refrigerant flowing out of the first flow rate adjustment unit 15. The mixed refrigerant flowing out of the second junction 21 flows into the compressor 10. 【0151】 Figure 16 is a functional block diagram showing the configuration of the refrigeration cycle device 1d according to Embodiment 5. As shown in Figure 16, the control unit 123 according to Embodiment 5 controls the compressor drive unit 140, the blower 110, the first pressure reducing unit 13, the first flow rate adjustment unit 15, and the second flow rate adjustment unit 30. 【0152】 The control unit 123 controls the second flow rate adjustment unit 30 based on the disproportionation reactivity A of the first refrigerant calculated by the disproportionation reactivity calculation unit 122. Specifically, the control unit 123 adjusts the flow rate of the mixed refrigerant flowing into the second flow rate adjustment unit 30 by controlling the opening degree of the second flow rate adjustment unit 30. In this way, by adjusting the flow rate of the mixed refrigerant flowing into the second flow rate adjustment unit 30 by the control unit 123, the flow rate of the mixed refrigerant flowing into the first internal heat exchanger 85 can be adjusted, and the amount of heat exchanged in the first internal heat exchanger 85 can be controlled. 【0153】The control unit 123 controls the second flow rate adjustment unit 30 based on the composition ratio of the first refrigerant calculated by the composition ratio calculation unit 121. Specifically, the control unit 123 adjusts the flow rate of the mixed refrigerant flowing into the second flow rate adjustment unit 30 by controlling the opening degree of the second flow rate adjustment unit 30. In this way, by adjusting the flow rate of the mixed refrigerant flowing into the second flow rate adjustment unit 30 by the control unit 123, the flow rate of the mixed refrigerant flowing into the first internal heat exchanger 85 can be adjusted, and the amount of heat exchanged in the first internal heat exchanger 85 can be controlled. 【0154】 <Control Flow of the Refrigeration Cycle Circuit According to Embodiment 5> The control flow of the refrigeration cycle circuit 2d according to Embodiment 5 will be described. Figure 17 is a control flowchart of the refrigeration cycle circuit 2d according to Embodiment 5. 【0155】 First, in step S200, the pressure detection unit 58 detects the suction pressure Ps or discharge pressure Pd of the compressor 10. Alternatively, the temperature detection unit 59 detects the suction temperature Ts or discharge temperature Td of the compressor 10. Alternatively, the current detection unit 70 detects at least one of the armature current Ia flowing through the motor 50 of the compressor 10 and the inverter current Ii flowing through the inverter 145. It is sufficient to detect at least one of the pressure, temperature, armature current Ia, and inverter current Ii. 【0156】 Next, in step S201, the pressure and temperature of the mixed refrigerant inside the compressor 10 are estimated based on at least one of the suction pressure Ps or discharge pressure Pd of the compressor 10 detected in step S200, the suction temperature Ts or discharge temperature Td of the compressor 10, and at least one of the armature current Ia and inverter current Ii. 【0157】Next, in step S202, the composition ratio calculation unit 121 determines whether or not to estimate the composition ratio of the first refrigerant in the mixed refrigerant inside the compressor 10. If the composition ratio of the first refrigerant is to be estimated, the process proceeds to step S203. If the composition ratio of the first refrigerant is not to be estimated, the process proceeds to step S204. For example, when controlling the opening degree of the first flow rate adjustment unit 15 with high precision, by determining in step S202 that the composition ratio of the first refrigerant should be estimated, the degree of disproportionation reactivity A can be calculated based on information from both the composition ratio of the first refrigerant and the pressure and temperature inside the compressor 10. This improves the accuracy of the calculation of the degree of disproportionation reactivity A, and allows for high-precision control of the opening degree of the first flow rate adjustment unit 15. Furthermore, when quickly controlling the opening degree of the first flow rate adjustment unit 15, by determining in step S202 that the composition ratio of the first refrigerant should not be estimated, the degree of disproportionation reactivity A can be calculated based only on the pressure and temperature information inside the compressor 10. This reduces the computational load required to calculate the degree of disproportionation reactivity A due to not estimating the composition ratio of the first refrigerant, thereby improving the responsiveness of controlling the opening degree of the first flow rate adjustment unit 15. 【0158】 Next, in step S203, the composition ratio of the first refrigerant in the mixed refrigerant inside the compressor 10 is estimated based on the suction pressure Ps or discharge pressure Pd of the compressor 10 detected in step S200, the suction temperature Ts or discharge temperature Td of the compressor 10, and at least one of the armature current Ia and inverter current Ii. That is, the composition ratio of the first refrigerant in the mixed refrigerant inside the compressor 10 is estimated. Note that step S201 may be executed after step S203, but executing step S201 first can improve the accuracy of the estimation of the composition ratio of the first refrigerant in step S203. Also, if it is determined in step S202 that the composition ratio of the first refrigerant does not need to be estimated, step S203 is not executed. Executing step S203 is not necessarily required, and it is possible to skip step S203 and not estimate the composition ratio of the first refrigerant in the mixed refrigerant inside the compressor 10. 【0159】Next, in step S204, the disproportionation reactivity calculation unit 122 calculates the disproportionation reactivity A based on the pressure and temperature inside the compressor 10 estimated in step S201 and the composition ratio of the first refrigerant in the mixed refrigerant inside the compressor 10 estimated in step S203. The disproportionation reactivity A is an indicator of the disproportionation reaction that occurs in the mixed refrigerant. If the disproportionation reactivity calculation unit 122 determines in step S202 that the composition ratio of the first refrigerant should not be estimated and does not execute step S203, it may calculate the disproportionation reactivity A based on the pressure and temperature inside the compressor 10 estimated in step S201. 【0160】 Next, in step S205, the disproportionation reactivity A calculated by the disproportionation reactivity calculation unit 122 is compared with the disproportionation reactivity threshold Ath. If A ≥ Ath, it is estimated that there is a possibility of a disproportionation reaction occurring in the mixed refrigerant, and the process proceeds to step S206. If A < Ath, it is estimated that there is a low possibility of a disproportionation reaction occurring in the mixed refrigerant, and the process proceeds to step S211. 【0161】 Next, in step S206, the control unit 123 controls the opening of the first flow rate adjustment unit 15 to increase. This reduces the composition ratio of the first refrigerant in the mixed refrigerant flowing into the suction pipe 54 of the compressor 10, thereby suppressing the occurrence of a disproportionation reaction of the mixed refrigerant inside the compressor 10. 【0162】 Next, in step S207, the discharge temperature Td of the mixed refrigerant discharged from the discharge pipe 55 of the compressor 10 is detected. 【0163】 Next, in step S208, the detected discharge temperature Td is compared with the discharge temperature threshold Tdth. The discharge temperature threshold Tdth is the maximum temperature threshold for the discharge temperature Td, and the maximum temperature that the compressor 10 can tolerate is set as the discharge temperature threshold Tdth. The maximum temperature of the compressor 10 is determined by the maximum capacity of the compressor 10 and the heat resistance of the materials of the components constituting the compression mechanism 52 and the electric motor 50. As an example, the discharge temperature threshold Tdth is, for example, 100 to 120 [°C]. If Td ≤ Tdth, the process proceeds to step S209. If Td > Tdth, the process proceeds to step S210. 【0164】Next, in step S209, if it is determined in step S208 that Td ≤ Tdth, the control unit 123 controls the opening of the second flow rate adjustment unit 30 to increase. 【0165】 Next, in step S210, if it is determined in step S208 that Td > Tdth, discharge temperature suppression control is performed to suppress the discharge temperature Td. Discharge temperature suppression control is a control that reduces the discharge temperature Td by controlling the circulation amount of the mixed refrigerant to suppress the discharge temperature Td. In discharge temperature suppression control, for example, the control unit 123 controls the opening of the first pressure reducing unit 13 to increase. This increases the circulation amount of the mixed refrigerant circulating in the refrigeration cycle circuit 2d, which cools the compressor 10 with the mixed refrigerant and reduces the discharge temperature Td. Alternatively, the control unit 123 may control the rotation speed of the compressor 10 to decrease, in which case the control unit 123 controls the frequency of the armature current Ia to decrease. 【0166】 Next, in step S211, if it is determined in step S205 that A < Ath, the degree of subcooling SC of the condenser 11 is calculated. The degree of subcooling SC is the temperature difference between the saturated refrigerant temperature in the condenser 11 and the outlet refrigerant temperature of the condenser 11. Therefore, the degree of subcooling SC can be calculated by detecting the saturated refrigerant temperature and the outlet refrigerant temperature of the condenser 11. 【0167】 Next, in step S212, the deviation |SC - SCtv| between the acquired supercooling degree SC and the supercooling degree target value SCtv is calculated, and |SC - SCtv| is compared with the supercooling degree threshold SCth. The supercooling degree target value SCtv is the target value for the supercooling degree SC. The supercooling degree threshold SCdth is the threshold for the deviation between the supercooling degree SC and the supercooling degree target value SCtv. If |SC - SCtv| ≤ SCth, proceed to step S213. If |SC - SCtv| > SCth, proceed to step S214. 【0168】Next, in step S213, the control unit 123 controls the opening of the first flow rate adjustment unit 15 and the second flow rate adjustment unit 30 to be reduced. Since it is determined in step S205 that A < Ath, the possibility of a disproportionation reaction of the mixed refrigerant occurring is low, and by reducing the opening of the first flow rate adjustment unit 15, the composition ratio of the first refrigerant in the mixed refrigerant circulating in the main path 6 can be increased. Generally, a mixed refrigerant with a low boiling point, such as the first refrigerant, has the effect of increasing the efficiency of the refrigeration cycle system, and therefore the efficiency of the refrigeration cycle circuit 2d can be improved. In addition, by reducing the opening of the second flow rate adjustment unit 30, the mixed refrigerant flows more easily into the fifth bypass circuit 7d, thereby suppressing the pressure loss of the mixed refrigerant generated in the first internal heat exchanger 85 and improving the efficiency of the refrigeration cycle circuit 2d. 【0169】 Next, in step S214, the control unit 123 controls the opening of the first flow rate adjustment unit 15. That is, since it was determined in step S212 that |SC - SCtv| > SCth, the opening of the first flow rate adjustment unit 15 is adjusted so that the supercooling degree SC approaches the supercooling degree target value SCtv. 【0170】 <Effects of the Refrigeration Cycle System According to Embodiment 5> In the refrigeration cycle circuit 2d according to Embodiment 5, the mixed refrigerant flowing out from the second branching section 26 is branched to the first internal heat exchanger 85 and the fifth bypass pipe 7d. As a result, the flow rate of the mixed refrigerant flowing to the first internal heat exchanger 85 is reduced, and the pressure loss of the mixed refrigerant generated inside the first internal heat exchanger 85 can be reduced. This improves the efficiency of the refrigeration cycle circuit 2d. 【0171】 Furthermore, in the refrigeration cycle device 1d according to Embodiment 5, the amount of heat exchange in the first internal heat exchanger 85 can be controlled by adjusting the opening degree of the second flow rate adjustment unit 30 in the control unit 123, without having to adjust the opening degree of the first pressure reduction unit 13 in the control unit 123. 【0172】In other words, the first flow rate adjustment unit 15 and the second flow rate adjustment unit 30 can adjust the composition ratio of the first refrigerant in the mixed refrigerant, and the first pressure reduction unit 13 can adjust the amount of heat exchange in the refrigeration cycle circuit 2d. As a result, the composition ratio of the first refrigerant in the mixed refrigerant and the amount of heat exchange in the refrigeration cycle circuit 2d can be adjusted independently, making it easy to set the refrigeration cycle circuit 2d to an appropriate operating point. This improves the efficiency of the refrigeration cycle circuit 2d. 【0173】 Based on the above, the refrigeration cycle circuit 2d according to Embodiment 5 can further improve efficiency compared to the refrigeration cycle circuit 2 according to Embodiment 1. 【0174】 Furthermore, the fourth bypass pipe 7c according to Embodiment 5 can be combined not only with the refrigeration cycle circuit 2 according to Embodiment 1, but also with the refrigeration cycle circuits 2a, 2b, and 2c according to Embodiment 2-4. 【0175】 Embodiment 6. <Configuration and Operation of the Refrigeration Cycle Circuit According to Embodiment 6> The configuration and operation of the refrigeration cycle circuit 2e according to Embodiment 6 will be described. Note that matters common to Embodiment 5 will be omitted from the explanation, and matters different from Embodiment 5 will be described. 【0176】 Figure 18 is a refrigerant circuit diagram showing a refrigeration cycle circuit 2e according to Embodiment 6. Compared to the refrigeration cycle circuit 2d according to Embodiment 5, the refrigeration cycle circuit 2e according to Embodiment 6 has the second flow rate adjustment unit 30 removed, and a third flow rate adjustment unit 31 is provided in the fourth bypass piping 7c. 【0177】 The third flow rate adjustment unit 31 is provided between the second branching unit 26 and the third merging unit 22. 【0178】 The operation of the refrigeration cycle circuit 2e according to Embodiment 6 will now be described. The mixed refrigerant flowing out from the evaporator 12 flows into the second branching section 26. The mixed refrigerant flowing out from the second branching section 26 is split into a mixed refrigerant that flows into the first internal heat exchanger 85 and a mixed refrigerant that flows into the third flow rate adjustment section 31. 【0179】Figure 19 is a functional block diagram showing the configuration of the refrigeration cycle device 1e according to Embodiment 6. As shown in Figure 19, the control unit 123 according to Embodiment 6 controls the compressor drive unit 140, the blower 110, the first pressure reducing unit 13, the first flow rate adjustment unit 15, and the third flow rate adjustment unit 31. 【0180】 The control unit 123 controls the third flow rate adjustment unit 31 based on the disproportionation reactivity A of the first refrigerant calculated by the disproportionation reactivity calculation unit 122. Specifically, the control unit 123 controls the flow rate of the mixed refrigerant flowing into the third flow rate adjustment unit 31 by adjusting the opening of the third flow rate adjustment unit 31. In this way, by controlling the flow rate of the mixed refrigerant flowing into the third flow rate adjustment unit 31 by the control unit 123, the flow rate of the mixed refrigerant flowing into the first internal heat exchanger 85 can be adjusted, and the amount of heat exchanged in the first internal heat exchanger 85 can be controlled. 【0181】 The control unit 123 controls the third flow rate adjustment unit 31 based on the composition ratio of the first refrigerant calculated by the composition ratio calculation unit 121. Specifically, the control unit 123 controls the flow rate of the mixed refrigerant flowing into the third flow rate adjustment unit 31 by adjusting the opening degree of the third flow rate adjustment unit 31. In this way, by controlling the flow rate of the mixed refrigerant flowing into the third flow rate adjustment unit 31 with the control unit 123, the flow rate of the mixed refrigerant flowing into the first internal heat exchanger 85 can be adjusted, and the amount of heat exchanged in the first internal heat exchanger 85 can be controlled. 【0182】 <Effects of the Refrigeration Cycle Device According to Embodiment 6> In the refrigeration cycle circuit 2e according to Embodiment 6, the mixed refrigerant flowing out from the second branching section 26 is branched to the first internal heat exchanger 85 and the third flow rate adjustment section 31. As a result, the flow rate of the mixed refrigerant flowing to the first internal heat exchanger 85 is reduced, and the pressure loss of the mixed refrigerant generated inside the first internal heat exchanger 85 can be reduced. This improves the efficiency of the refrigeration cycle circuit 2e. 【0183】 Furthermore, in the refrigeration cycle device 1e according to embodiment 6, the amount of heat exchange in the first internal heat exchanger 85 can be controlled by adjusting the opening degree of the third flow rate adjustment unit 31 in the control unit 123, without having to adjust the opening degree of the first pressure reduction unit 13 in the control unit 123. 【0184】In other words, the first flow rate adjustment unit 15 and the third flow rate adjustment unit 31 can adjust the composition ratio of the first refrigerant in the mixed refrigerant, and the first pressure reduction unit 13 can adjust the amount of heat exchange in the refrigeration cycle circuit 2e. As a result, the composition ratio of the first refrigerant in the mixed refrigerant and the amount of heat exchange in the refrigeration cycle circuit 2e can be adjusted independently, making it easy to set the refrigeration cycle circuit 2e to an appropriate operating point. This improves the efficiency of the refrigeration cycle circuit 2e. 【0185】 Based on the above, the refrigeration cycle circuit 2e according to Embodiment 6 can further improve efficiency compared to the refrigeration cycle circuit 2 according to Embodiment 1. 【0186】 Furthermore, the third flow rate adjustment unit 31 according to Embodiment 6 can be combined not only with the refrigeration cycle circuit 2 according to Embodiment 1, but also with the refrigeration cycle circuits 2a, 2b, 2c, and 2d according to Embodiment 2-5. 【0187】 Embodiment 7. <Configuration and Operation of the Refrigeration Cycle Circuit According to Embodiment 7> The configuration and operation of the refrigeration cycle circuit 2f according to Embodiment 7 will be described. Note that matters common to Embodiment 1 will be omitted from the explanation, and matters different from Embodiment 1 will be described. 【0188】 Figure 20 is a refrigerant circuit diagram showing a refrigeration cycle circuit 2f according to Embodiment 7. Compared to the refrigeration cycle circuit 2 according to Embodiment 1, the refrigeration cycle circuit 2f according to Embodiment 7 includes an accumulator 45. 【0189】 The accumulator 45 is located in the main path 6 and is installed between the outlet side of the first internal heat exchanger 85 and the second junction 21. The accumulator 45 separates the gas-liquid two-phase mixed refrigerant flowing out of the evaporator 12 into gaseous refrigerant and liquid refrigerant, and stores any excess liquid refrigerant inside during operation. 【0190】 The operation of the refrigeration cycle circuit 2f according to Embodiment 7 will now be described. The mixed refrigerant that flows out from the first internal heat exchanger 85 flows into the second confluence section 21 via the accumulator 45. The refrigerant that flows out from the second confluence section 21 merges with the mixed refrigerant that flows out from the first flow rate adjustment section 15 and flows into the compressor 10. 【0191】 <Effects of the Refrigeration Cycle Circuit According to Embodiment 7> The refrigeration cycle circuit 2f according to Embodiment 7 can prevent liquid backflow of the compressor 10 by providing an accumulator 45. Liquid backflow is a phenomenon in which a portion of the mixed refrigerant that has been gasified in the evaporator 12 remains as liquid refrigerant, and this liquid refrigerant is drawn into the compressor 10. When liquid backflow occurs, liquid refrigerant enters the compression mechanism 52, and liquid compression occurs in the compression mechanism 52, which may cause the compressor 10 to malfunction. Therefore, it is desirable to prevent liquid backflow. 【0192】 When an accumulator 45 is installed in a conventional refrigeration cycle system, the second refrigerant has a higher boiling point than the first refrigerant, making it easier for the second refrigerant to accumulate in the accumulator 45 as a liquid refrigerant. As a result, the composition ratio of the first refrigerant in the mixed refrigerant inside the compressor 10 increases, making it more likely that the mixed refrigerant will undergo a disproportionation reaction. 【0193】 On the other hand, the refrigeration cycle circuit 2f according to Embodiment 7 can control the composition ratio of the first refrigerant in the mixed refrigerant inside the compressor 10. Therefore, even if an accumulator 45 is provided, the composition ratio of the first refrigerant in the mixed refrigerant inside the compressor 10 can be reduced, and the occurrence of disproportionation reactions of the mixed refrigerant can be suppressed. 【0194】 The refrigeration cycle circuit 2f according to Embodiment 7, by providing an accumulator 45, can prevent liquid backflow in the compressor 10 as described above. Therefore, liquid compression in the compression mechanism 52 of the compressor 10 can be prevented, and the reliability of the compressor 10 can be improved. Also, similar to Embodiments 1-6, the refrigeration cycle circuit 2f according to Embodiment 7 has a higher composition ratio of the first refrigerant in the mixed refrigerant flowing through the main path 6. Since a low boiling point mixed refrigerant has the effect of improving the efficiency of the refrigeration cycle device, the efficiency of the refrigeration cycle circuit 2f can be improved. 【0195】 Furthermore, the accumulator 45 according to Embodiment 7 can be combined not only with the refrigeration cycle circuit 2 according to Embodiment 1, but also with the refrigeration cycle circuits 2a, 2b, 2c, 2d, and 2e according to Embodiments 2-6. 【0196】Figure 21 is a refrigerant circuit diagram showing another example of the refrigeration cycle circuit 2f according to Embodiment 7. As shown in Figure 21, an accumulator 45 may be provided in the main path 6 between the second junction 21 and the suction pipe 54 side of the compressor 10. Also, in the refrigeration cycle circuits 2d and 2e according to Embodiments 5-6, an accumulator 45 may be provided between the outlet side of the third junction 22 and the second junction 21. 【0197】 Embodiment 8. <Configuration and Operation of the Refrigeration Cycle Circuit According to Embodiment 8> The configuration and operation of the refrigeration cycle circuit 2g according to Embodiment 8 will be described. Note that matters common to Embodiment 1 will be omitted from the explanation, and matters different from Embodiment 1 will be described. 【0198】 Figure 22 is a refrigerant circuit diagram showing a refrigeration cycle circuit 2g according to Embodiment 8. Instead of the first pressure reducing unit 13 according to Embodiment 1, a power receiver 90 is provided in the refrigeration cycle circuit 2g according to Embodiment 8. 【0199】 The power receiver 90 has a gas-liquid separation function and stores liquid refrigerant. The power receiver 90 consists of a liquid reservoir 91, a second pressure reduction unit 92, a third pressure reduction unit 93, and a heat recovery unit 94. 【0200】 The liquid reservoir 91 stores liquid refrigerant and adjusts the amount of liquid refrigerant. The inside of the liquid reservoir 91 has a power receiver inlet pipe 95, one end of which is connected to the evaporator 12 and the other end to the heat recovery unit 94, and a power receiver outlet pipe 96, one end of which is connected to the heat recovery unit 94 and the other end to the first internal heat exchanger 85. The heat recovery unit 94 is the part that recovers heat by transferring the heat contained in the liquid refrigerant in the liquid reservoir 91 to the mixed refrigerant flowing through the refrigerant piping. 【0201】 The second pressure reducing section 92 is provided between the outlet side of the condenser 11 and the inlet side of the liquid reservoir section 91. The second pressure reducing section 92 reduces the pressure of the high-temperature, high-pressure liquid refrigerant flowing out of the condenser 11. The mixed refrigerant, reduced in pressure by the second pressure reducing section 92, becomes a two-phase gas-liquid state and flows into the liquid reservoir section 91 where it is stored. 【0202】The third pressure reducing section 93 is provided between the outlet side of the liquid reservoir section 91 and the inlet side of the evaporator 12. The third pressure reducing section 93 reduces the pressure of the liquid refrigerant flowing out of the liquid reservoir section 91. The mixed refrigerant reduced in pressure by the third pressure reducing section 93 becomes a low-temperature, low-pressure gas-liquid two-phase mixed refrigerant and flows into the evaporator 12. 【0203】 The low-temperature, low-pressure gaseous refrigerant flowing out of the evaporator 12 flows into the heat recovery unit 94 via the power receiver inlet piping 95. The mixed refrigerant flowing into the heat recovery unit 94 exchanges heat with the mixed refrigerant in the liquid reservoir 91. This promotes the gasification of any liquid refrigerant present in the heat recovery unit 94. The mixed refrigerant flowing out of the heat recovery unit 94 flows into the first internal heat exchanger 85. 【0204】 Figure 23 is a functional block diagram showing the configuration of the refrigeration cycle device 1g according to Embodiment 8. As shown in Figure 23, the control unit 123 according to Embodiment 8 controls the compressor drive unit 140, the blower 110, the second pressure reducing unit 92, the third pressure reducing unit 93, and the first flow rate adjustment unit 15. 【0205】 By adjusting the pressure of the mixed refrigerant flowing into the second pressure reduction section 92 and the pressure of the mixed refrigerant flowing into the third pressure reduction section 93 using the control unit 123, the amount of liquid refrigerant stored in the liquid reservoir section 91 can be adjusted. This allows the refrigeration cycle circuit 2g to be operated at a desired operating point. 【0206】 <Effects of the Refrigeration Cycle Circuit According to Embodiment 8> The refrigeration cycle circuit 2g according to Embodiment 8 can be operated at a desired operating point by adjusting the amount of liquid refrigerant stored in the liquid reservoir 91, thanks to the power receiver 90. As an effect of the power receiver 90, the heat recovery unit 94 of the power receiver 90 promotes the gasification of the mixed refrigerant flowing into the compressor 10, so that the mixed refrigerant flowing out of the evaporator 12 can be in a gas-liquid two-phase state. This improves the heat transfer efficiency of the evaporator 12, and thus improves the efficiency of the refrigeration cycle circuit 2g. 【0207】Furthermore, the power receiver 90, compared to the accumulator 45, can make it less likely for the composition of the non-azeotropic mixed refrigerant to change when applied to a refrigeration cycle system. Non-azeotropic mixed refrigerants have the property that the mixed refrigerant components with high boiling points accumulate as liquid refrigerant inside the accumulator 45. In other words, in a refrigeration cycle circuit using an accumulator 45, the composition of the non-azeotropic mixed refrigerant is prone to change. The refrigeration cycle circuit 2g according to Embodiment 8 is configured with a power receiver 90 instead of an accumulator 45, making it less likely for the composition of the non-azeotropic mixed refrigerant to change and thus more stable, thus facilitating controllability for changing the composition ratio of the first refrigerant in the mixed refrigerant. 【0208】 Furthermore, the power receiver 90 according to Embodiment 8 can be combined not only with the refrigeration cycle circuit 2 according to Embodiment 1, but also with the refrigeration cycle circuits 2a, 2b, 2c, 2d, 2e, and 2f according to Embodiment 2-7. 【0209】 Embodiment 9. <Configuration and Operation of the Refrigeration Cycle Device According to Embodiment 9> The configuration and operation of the refrigeration cycle circuit 2h according to Embodiment 9 will be described. Matters common to Embodiment 1 will be omitted from the explanation, and matters that differ from Embodiment 1 will be described. 【0210】 Figure 24 is a refrigerant circuit diagram showing a refrigeration cycle circuit 2h according to Embodiment 9. The refrigeration cycle circuit 2h according to Embodiment 9 is provided with an accumulator 45 according to Embodiment 7 and a power receiver 90 according to Embodiment 8. 【0211】The operation of the refrigeration cycle circuit 2h according to Embodiment 9 will now be described. By increasing the opening of the second pressure reducing unit 92 or the third pressure reducing unit 93, the mixed refrigerant flowing out from the power receiver 90 will contain more of the liquid refrigerant inside the liquid reservoir unit 91, so that a mixed refrigerant with a low degree of dryness will circulate in the refrigeration cycle circuit 2h. As a result, the degree of dryness of the mixed refrigerant flowing into the accumulator 45 will decrease. That is, the liquid refrigerant ratio in the power receiver 90 will decrease, and the liquid refrigerant ratio in the accumulator 45 will increase. As mentioned above, the second refrigerant has a higher boiling point than the first refrigerant in the mixed refrigerant, so the second refrigerant tends to accumulate in the accumulator 45 as liquid refrigerant. As a result, the liquid refrigerant ratio in the accumulator 45 will increase, and more of the second refrigerant will accumulate in the accumulator 45. This makes it possible to increase the composition ratio of the first refrigerant in the mixed refrigerant circulating in the main path 6. 【0212】 By reducing the opening of the second pressure reducing section 92 or the third pressure reducing section 93, the liquid refrigerant inside the liquid reservoir section 91 is less likely to be included in the mixed refrigerant flowing out of the power receiver 90, so that a drier mixed refrigerant circulates in the refrigeration cycle circuit 2h. As a result, the dryness of the mixed refrigerant flowing into the accumulator 45 increases. That is, the liquid refrigerant ratio in the power receiver 90 increases and the liquid refrigerant ratio in the accumulator 45 decreases, so the first refrigerant is more likely to accumulate in the accumulator 45. As a result, the composition ratio of the first refrigerant in the mixed refrigerant circulating in the main path 6 can be reduced. 【0213】 Furthermore, the refrigeration cycle circuit 2h according to Embodiment 9 includes a first flow rate adjustment unit 15 between the gas-liquid separator 80 and the second confluence unit 21. By lowering the opening of the first flow rate adjustment unit 15, the amount of refrigerant discharged from the compressor 10 and flowing into the first bypass piping 7 can be reduced. This makes it possible to increase the composition ratio of the first refrigerant in the mixed refrigerant flowing through the main path 6 where the condenser 11 and evaporator 12 are located. Since a mixed refrigerant with a low boiling point has the effect of increasing the efficiency of the refrigeration cycle device, the efficiency of the refrigeration cycle circuit 2h can be improved. 【0214】<Effects of the Refrigeration Cycle Circuit According to Embodiment 9> The refrigeration cycle circuit 2h according to Embodiment 9 can obtain the effects described in Embodiments 7 and 8 by providing a power receiver 90 and an accumulator 45. Specifically, by providing the accumulator 45, liquid backflow of the compressor 10 can be prevented, thus preventing liquid compression in the compression mechanism 52 of the compressor 10 and improving the reliability of the compressor 10. Furthermore, by providing the power receiver 90, the gasification of the mixed refrigerant flowing into the compressor 10 can be promoted, so that the mixed refrigerant flowing out of the evaporator 12 can be in a gas-liquid two-phase state. As a result, the heat transfer efficiency of the evaporator 12 can be improved, and thus the efficiency of the refrigeration cycle circuit 2h can be improved. 【0215】 Embodiment 10. <Configuration and Operation of the Refrigeration Cycle System According to Embodiment 10> The configuration and operation of the refrigeration cycle circuit 2J according to Embodiment 10 will be described. Note that matters common to Embodiment 10 will be omitted from the explanation, and matters different from Embodiment 1 will be described. 【0216】 Figure 25 is a refrigerant circuit diagram showing a refrigeration cycle circuit 2J according to this embodiment 10. In the refrigeration cycle circuit 2J according to this embodiment 10, the gas-liquid separator 80, the first internal heat exchanger 85, the first flow rate adjustment unit 15, the first branching unit 25, the first junction unit 20, the second junction unit 21, the first bypass pipe 7, the second bypass pipe 7a, and the third bypass pipe 7b are removed from the refrigeration cycle circuit 2h according to embodiment 9. 【0217】 In other words, the refrigeration cycle circuit 2J according to this embodiment 10 consists of a compressor 10, a condenser 11, an evaporator 12, a system control unit 5, an accumulator 45 according to embodiment 7, and a power receiver 90 according to embodiment 8. The accumulator 45 is provided between the liquid reservoir 91 and the suction pipe 54 side of the compressor 10. 【0218】In the refrigeration cycle circuits 2, 2a, 2b, 2c, 2d, 2e, 2f, 2g, and 2h according to Embodiments 1-9, the boiling point of the second refrigerant in the mixed refrigerant was required to be higher than the boiling point of the first refrigerant at the same pressure. On the other hand, in the refrigeration cycle circuit 2J according to Embodiment 10, either a mixed refrigerant in which the boiling point of the second refrigerant is higher than the boiling point of the first refrigerant at the same pressure, or a mixed refrigerant in which the boiling point of the second refrigerant is lower than the boiling point of the first refrigerant at the same pressure can be used. 【0219】 The operation of the refrigeration cycle circuit 2J according to this embodiment 10 will be described. First, the case in which a mixed refrigerant is used in which the boiling point of the second refrigerant is higher than the boiling point of the first refrigerant at the same pressure will be described. By increasing the opening of the second pressure reduction section 92 or the third pressure reduction section 93 of the power receiver 90, the mixed refrigerant flowing out of the power receiver 90 will contain more of the liquid refrigerant inside the liquid reservoir section 91, so that a mixed refrigerant with a low degree of dryness will circulate in the refrigeration cycle circuit 2J. As a result, the degree of dryness of the mixed refrigerant flowing into the accumulator 45 is reduced. That is, the liquid refrigerant ratio in the power receiver 90 decreases, and the liquid refrigerant ratio in the accumulator 45 increases. Since the second refrigerant has a higher boiling point than the first refrigerant in the mixed refrigerant, the second refrigerant tends to accumulate in the accumulator 45 as liquid refrigerant. As a result, the liquid refrigerant ratio in the accumulator 45 increases, causing more of the second refrigerant to accumulate in the accumulator 45. This makes it possible to increase the composition ratio of the first refrigerant in the mixed refrigerant circulating in the main path 6. 【0220】 By reducing the opening of the second pressure reducing section 92 or the third pressure reducing section 93, the liquid refrigerant inside the liquid reservoir section 91 is less likely to be included in the mixed refrigerant flowing out of the power receiver 90, so that a drier mixed refrigerant circulates in the refrigeration cycle circuit 2J. As a result, the dryness of the mixed refrigerant flowing into the accumulator 45 increases. That is, the liquid refrigerant ratio in the power receiver 90 increases and the liquid refrigerant ratio in the accumulator 45 decreases, so the first refrigerant is more likely to accumulate in the accumulator 45. As a result, the composition ratio of the first refrigerant in the mixed refrigerant circulating in the main path 6 can be reduced. 【0221】Next, we will explain the case where a mixed refrigerant is used in which the boiling point of the second refrigerant is lower than the boiling point of the first refrigerant at the same pressure. By increasing the opening of the second pressure reduction section 92 or the third pressure reduction section 93, the mixed refrigerant flowing out from the power receiver 90 contains more of the liquid refrigerant inside the liquid reservoir section 91, so that a mixed refrigerant with a low degree of dryness circulates in the refrigeration cycle circuit 2J. As a result, the degree of dryness of the mixed refrigerant flowing into the accumulator 45 is reduced. That is, the liquid refrigerant ratio in the power receiver 90 decreases, and the liquid refrigerant ratio in the accumulator 45 increases. As mentioned above, since the second refrigerant has a lower boiling point than the first refrigerant, the first refrigerant tends to accumulate in the accumulator 45 as liquid refrigerant. As a result, the liquid refrigerant ratio in the accumulator 45 increases, causing more of the first refrigerant to accumulate in the accumulator 45. This makes it possible to reduce the composition ratio of the first refrigerant in the mixed refrigerant circulating in the main path 6. 【0222】 By reducing the opening of the second pressure reducing section 92 or the third pressure reducing section 93, the liquid refrigerant inside the liquid reservoir section 91 is less likely to be included in the mixed refrigerant flowing out of the power receiver 90, so that a drier mixed refrigerant circulates in the refrigeration cycle circuit 2J. As a result, the dryness of the mixed refrigerant flowing into the accumulator 45 increases. That is, the liquid refrigerant ratio in the power receiver 90 increases and the liquid refrigerant ratio in the accumulator 45 decreases, so the second refrigerant is more likely to accumulate in the accumulator 45. As a result, the composition ratio of the first refrigerant in the mixed refrigerant circulating in the main path 6 can be increased. 【0223】In this embodiment 10, the refrigeration cycle circuit 2J adjusts the composition ratio of the first refrigerant in the mixed refrigerant using an accumulator 45 and a power receiver 90. In this case, since it takes time for the refrigerant to move within the refrigeration cycle circuit 2J, the refrigeration cycle circuits 2, 2a, 2b, 2c, 2d, 2e, 2f, 2g, and 2h according to embodiments 1-9 have superior control responsiveness. Therefore, it is desirable that the control unit 123 in this embodiment 10 controls the operation of the refrigeration cycle circuit 2J to stop if the disproportionation reactivity A calculated by the disproportionation reaction calculation unit 122 is high relative to the disproportionation reactivity threshold Ath. Because the refrigeration cycle circuit 2J in this embodiment 10 has fewer components, it can be miniaturized and cost-effective. 【0224】 <Effects of the Refrigeration Cycle Device According to Embodiment 10> In the refrigeration cycle circuit 2J according to Embodiment 10, the composition ratio of the first refrigerant in the mixed refrigerant can be adjusted by the accumulator 45 and the power receiver 90, so the refrigeration cycle circuit 2J can be constructed with a simple configuration with a small number of parts. This makes it possible to miniaturize and reduce the cost of the refrigeration cycle circuit 2J. 【0225】 The refrigeration cycle circuits 2, 2a, 2b, 2c, 2d, 2e, 2f, 2g, 2h, and 2J described in Embodiment 1-10 can be installed in air conditioning units 200, refrigerators, freezers, water heaters, etc. 【0226】 Figure 26 is a front view showing an example of an air conditioning system 200. As an example of providing the refrigeration cycle circuits 2, 2a, 2b, 2c, 2d, 2e, 2f, 2g, 2h, and 2J to the air conditioning system 200, for example, each means constituting the refrigeration cycle circuits 2, 2a, 2b, 2c, 2d, 2e, 2f, 2g, 2h, and 2J is provided separately in an indoor unit 210 and an outdoor unit 220, as shown in Figure 26. The indoor unit 210 cools or heats the space to be air-conditioned. The outdoor unit 220 circulates a mixed refrigerant and supplies heat to the indoor unit 210 to perform cooling or heating. 【0227】 The features of each embodiment described above can be combined with each other. 【0228】1, 1a, 1b, 1c, 1d, 1e, 1f, 1g, 1h, 1J Refrigeration cycle device, 2, 2a, 2b, 2c, 2d, 2e, 2f, 2g, 2h, 2J Refrigeration cycle circuit, 6 Main path, 7 First bypass piping, 7a Second bypass piping, 7b Third bypass piping, 7c Fourth bypass piping, 10 Compressor, 11 Condenser, 12 Evaporator, 13 First pressure reducing section, 15 First flow rate adjustment section, 20 First junction, 21 Second junction, 22 Third junction, 25 First branch section, 26 Second branch section, 30 Second flow rate adjustment section, 31 Third flow rate adjustment section, 35 Second internal heat exchanger, 36 Third internal heat exchanger, 45 Accumulator, 50 Motor, 52 Compression mechanism, 58 Pressure detection unit, 59 Temperature detection unit, 70 Current detection unit, 80 Gas-liquid separator, 85 First internal heat exchanger, 90 Power receiver, 91 Liquid reservoir unit, 92 Second pressure reduction unit, 93 Third pressure reduction unit, 94 Heat recovery unit, 120 Acquisition unit, 121 Composition ratio calculation unit, 122 Disproportionation reaction calculation unit, 123 Control unit, 145 Inverter, 200 Air conditioning unit, 210 Indoor unit, 220 Outdoor unit, A Disproportionation reactivity, Ath Disproportionation reactivity threshold, Ia Armature current, Ii Inverter current, Pd Discharge pressure, Ps Intake pressure, Td Discharge temperature, Ts Intake temperature.

Claims

1. A control device for controlling a refrigeration cycle circuit comprising: a main path through which a compressor, a condenser, a first pressure reducing unit, and an evaporator are sequentially connected; a mixed refrigerant circulating through the main path and containing a first refrigerant having the property of causing a disproportionation reaction and a second refrigerant having the property of not causing the disproportionation reaction; and a throttle unit for adjusting at least one of the pressure and flow rate of the mixed refrigerant, the control device comprising: an acquisition unit for acquiring at least one of the suction pressure, discharge pressure, suction temperature, and discharge temperature of the compressor; a calculation unit for calculating at least one of the disproportionation reactivity, which is an indicator that the mixed refrigerant causes the disproportionation reaction, or the composition ratio of the first refrigerant contained in the mixed refrigerant, based on at least one of the suction pressure, discharge pressure, suction temperature, and discharge temperature; and a control unit for controlling the throttle unit based on at least one of the disproportionation reactivity or composition ratio of the first refrigerant of the first refrigerant calculated by the calculation unit.

2. The control device according to claim 1, wherein the calculation unit is a disproportionation reactivity calculation unit for calculating the disproportionation reactivity.

3. The control device according to claim 2, wherein the disproportionation reactivity calculation unit calculates the disproportionation reactivity of the first refrigerant contained in the mixed refrigerant inside the compressor.

4. A control device according to claim 2 or 3, further comprising an inverter, wherein the compressor has a compression mechanism for compressing the mixed refrigerant and an electric motor for driving the compression mechanism, the inverter outputs a voltage to the electric motor, the acquisition unit further acquires at least one of the armature current flowing to the electric motor and the inverter current flowing to the inverter, and the disproportionation reactivity calculation unit calculates the disproportionation reactivity of the first refrigerant contained in the mixed refrigerant based on at least one of the suction pressure, the discharge pressure, the suction temperature and the discharge temperature, and at least one of the armature current and the inverter current.

5. The control device according to claim 1, wherein the calculation unit is a composition ratio calculation unit that calculates the composition ratio of the first refrigerant.

6. The control device according to claim 5, further comprising a disproportionation reactivity calculation unit for calculating the disproportionation reactivity.

7. The control device according to claim 5 or 6, wherein the control unit controls the throttle based on the composition ratio of the first refrigerant calculated by the composition ratio calculation unit.

8. The control device according to any one of claims 5 to 7, wherein the composition ratio calculation unit calculates the composition ratio of the first refrigerant contained in the mixed refrigerant inside the compressor.

9. A control device according to any one of claims 5 to 8, further comprising an inverter, wherein the compressor has a compression mechanism for compressing the mixed refrigerant and an electric motor for driving the compression mechanism, the inverter outputs a voltage to the electric motor, the acquisition unit further acquires at least one of the armature current flowing to the electric motor and the inverter current flowing to the inverter, and the composition ratio calculation unit calculates the composition ratio of the first refrigerant contained in the mixed refrigerant based on at least one of the suction pressure, the discharge pressure, the suction temperature and the discharge temperature, and at least one of the armature current and the inverter current.

10. The control device according to any one of claims 2 to 4 or 6, wherein the throttling section is a first flow rate adjustment section for adjusting the flow rate of the mixed refrigerant, and the control unit increases the opening of the first flow rate adjustment section when the disproportionation reactivity of the first refrigerant calculated by the disproportionation reactivity calculation section is equal to or greater than a disproportionation reactivity threshold.

11. The control device according to any one of claims 5 to 9, wherein the throttling section is a first flow rate adjustment section for adjusting the flow rate of the mixed refrigerant, and the control unit increases the opening of the first flow rate adjustment section when the composition ratio of the first refrigerant calculated by the composition ratio calculation section is equal to or greater than a composition ratio threshold.

12. The control device according to any one of claims 2 to 4 or 6, wherein the throttling section is a first pressure reducing section for adjusting the pressure of the mixed refrigerant, and the control unit reduces the opening of the first pressure reducing section when the disproportionation reactivity of the first refrigerant calculated by the disproportionation reactivity calculation section is equal to or greater than a disproportionation reactivity threshold.

13. The control device according to any one of claims 5 to 9, wherein the throttling section is a first pressure reducing section for adjusting the pressure of the mixed refrigerant, and the control unit reduces the opening of the first pressure reducing section when the composition ratio of the first refrigerant calculated by the composition ratio calculation section is equal to or greater than a composition ratio threshold.

14. The control device according to any one of claims 2 to 4 or 6, wherein the throttle portion is a power receiver comprising a second pressure reducing portion capable of changing the pressure of the mixed refrigerant and a third pressure reducing portion capable of changing the pressure of the mixed refrigerant, and the control unit reduces at least one of the opening of the second pressure reducing portion or the opening of the third pressure reducing portion when the disproportionation reactivity of the first refrigerant calculated by the disproportionation reactivity calculation portion is equal to or greater than a disproportionation reactivity threshold.

15. The control device according to any one of claims 5 to 9, wherein the throttle is a power receiver comprising a second pressure reducing unit capable of changing the pressure of the mixed refrigerant and a third pressure reducing unit capable of changing the pressure of the mixed refrigerant, and the control unit reduces at least one of the opening degree of the second pressure reducing unit or the opening degree of the third pressure reducing unit when the composition ratio of the first refrigerant calculated by the composition ratio calculation unit is equal to or greater than a composition ratio threshold.

16. A control device according to any one of claims 1 to 11; a main path through which a compressor, a condenser, a first pressure reducing unit, and an evaporator are sequentially connected; a mixed refrigerant circulating in the main path and containing a first refrigerant having the property of causing a disproportionation reaction and a second refrigerant having the property of not causing the disproportionation reaction; a first branch section provided between the discharge pipe side of the compressor and the inlet side of the condenser; a first confluence section provided between the first branch section and the inlet side of the condenser; a second confluence section provided between the outlet side of the evaporator and the suction pipe side of the compressor; a bypass path branching off from a path branched from the first branch section and joining the first confluence section and the second confluence section; a gas-liquid separator provided on the bypass path and having a refrigerant inlet into which the mixed refrigerant flows, a gas refrigerant outlet from which the gas refrigerant flows out and which separates the mixed refrigerant into a gas refrigerant and a liquid refrigerant, and a liquid refrigerant outlet from which the liquid refrigerant flows out. A refrigeration cycle device comprising: a first bypass pipe provided between the first branching section and the refrigerant inlet of the gas-liquid separator; a second bypass pipe provided between the first junction section and the gas refrigerant outlet of the gas-liquid separator; a third bypass pipe provided between the liquid refrigerant outlet of the gas-liquid separator and the second junction section; a throttling section provided between the liquid refrigerant outlet of the gas-liquid separator and the second junction section; an acquisition section for acquiring at least one of the suction pressure, discharge pressure, suction temperature, and discharge temperature of the compressor; and a control unit for controlling the throttling section based on at least one of the suction pressure, discharge pressure, suction temperature, and discharge temperature, wherein the throttling section is a first flow rate adjustment section for adjusting the flow rate of the mixed refrigerant.

17. The refrigeration cycle apparatus according to claim 16, wherein the second refrigerant has a higher boiling point than the first refrigerant at the same pressure.

18. The refrigeration cycle apparatus according to claim 16 or claim 17, further comprising a first internal heat exchanger provided between the first branching section and the refrigerant inlet of the gas-liquid separator, wherein the first internal heat exchanger is provided between the outlet side of the evaporator and the suction pipe side of the compressor.

19. The refrigeration cycle apparatus according to claim 18, wherein the second junction is provided between the outlet side of the first internal heat exchanger and the suction pipe side of the compressor.

20. The refrigeration cycle apparatus according to claim 18, wherein the second junction is provided between the outlet side of the evaporator and the inlet side of the first internal heat exchanger.

21. The refrigeration cycle apparatus according to claim 19 or claim 20, further comprising a second internal heat exchanger provided between the outlet side of the first flow rate adjustment section and the second confluence section.

22. The refrigeration cycle apparatus according to any one of claims 19 to 21, further comprising a third internal heat exchanger provided between the outlet side of the first internal heat exchanger and the refrigerant inlet of the gas-liquid separator.

23. The refrigeration cycle apparatus according to any one of claims 19 to 22, wherein the bypass path comprises a second branch section provided between the outlet side of the evaporator and the inlet side of the first internal heat exchanger, a third confluence section provided between the outlet side of the first internal heat exchanger and the second confluence section, a fourth bypass pipe provided between the second branch section and the third confluence section, and a second flow rate adjustment section provided between the second branch section and the inlet side of the first internal heat exchanger.

24. The refrigeration cycle apparatus according to claim 23, wherein the control unit controls the second flow rate adjustment unit based on the degree of disproportionation reactivity of the first refrigerant calculated by the calculation unit.

25. The refrigeration cycle apparatus according to any one of claims 19 to 22, wherein the bypass path comprises a second branch provided between the outlet side of the evaporator and the inlet side of the first internal heat exchanger, a third confluence provided between the outlet side of the first internal heat exchanger and the second confluence, a fourth bypass pipe provided between the second branch and the third confluence, and a third flow rate adjustment section provided between the second branch and the third confluence.

26. The refrigeration cycle apparatus according to claim 25, wherein the control unit controls the third flow rate adjustment unit based on the degree of disproportionation reactivity of the first refrigerant calculated by the calculation unit.

27. The refrigeration cycle apparatus according to any one of claims 19 to 26, further comprising an accumulator provided between the outlet side of the first internal heat exchanger and the second confluence section.

28. The refrigeration cycle apparatus according to any one of claims 19 to 26, further comprising an accumulator provided between the second confluence and the suction pipe side of the compressor.

29. A refrigeration cycle device comprising: a control device according to claim 14 or claim 15; a main path through which a compressor, a condenser, a throttle section, and an evaporator are sequentially connected; a mixed refrigerant circulating in the main path and containing a first refrigerant having the property of causing a disproportionation reaction and a second refrigerant having the property of not causing the disproportionation reaction; an acquisition unit for acquiring at least one of the suction pressure, discharge pressure, suction temperature, and discharge temperature of the compressor; and a control unit for controlling the throttle section based on at least one of the suction pressure, discharge pressure, suction temperature, and discharge temperature, wherein the throttle section is a power receiver comprising a liquid reservoir for adjusting the amount of liquid refrigerant, a second pressure reducing section provided between the outlet side of the condenser and the inlet side of the liquid reservoir, and a third pressure reducing section provided between the outlet side of the liquid reservoir and the inlet side of the evaporator; and an accumulator provided between the liquid reservoir and the suction pipe side of the compressor.

30. An air conditioning system comprising, for each means constituting the refrigeration cycle device according to any one of claims 16 to 29, an indoor unit that performs cooling or heating of a space to be air-conditioned, and an outdoor unit that circulates the mixed refrigerant and supplies heat to the indoor unit to perform the cooling or heating.

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