Method for operating refrigeration cycle circuit, refrigeration cycle composition, refrigeration cycle device, control method, and program

Abstract

Provided are: a method for operating a refrigeration cycle circuit wherein the method can improve the durability of the refrigeration cycle circuit; a refrigeration cycle device; a control method; and a program. This method for operating a refrigeration cycle circuit comprises: generating hydrogen fluoride from a working medium in a refrigeration cycle circuit (2) in which the working medium containing a refrigerant component capable of generating hydrogen fluoride circulates; reacting the hydrogen fluoride with a compound represented by formula (1) or formula (2); and circulating the working medium. In formula (1), at least one or more of R1 to R4 is selected from the hydroxy group, alkoxy groups, or acyl groups, and the remainder of R1 to R4 is selected from alkyl groups, the vinyl group, aryl groups, and substituents provided by their derivatization, and halogen groups. In formula (2), R5 and R6 are selected from the hydroxy group, alkoxy groups, acyl groups, alkyl groups, the vinyl group, aryl groups, and substituents provided by their derivatization, and halogen groups.

Description

Refrigeration cycle circuit operating method, refrigeration cycle composition, refrigeration cycle device, control method, and program

[0001] The present disclosure relates to a method for operating a refrigeration cycle circuit, a composition for a refrigeration cycle, a refrigeration cycle device, a control method, and a program.

[0002] Conventionally, R410A has been widely used as a working fluid (heat medium, refrigerant) for refrigeration cycle devices. However, R410A has a high global warming potential (GWP) of 2090. Therefore, from the perspective of preventing global warming, research and development has been conducted on working fluids with lower GWP. Patent Document 1 discloses 1,1,2-trifluoroethylene (HFO1123) as a working fluid with a lower GWP than R410A. Patent Document 2 discloses 1,2-difluoroethylene (HFO1132) as a working fluid with a lower GWP than R410A.

[0003] HFO1123 and HFO1132 have a smaller GWP than R410A, but this makes them less stable than R410A. For example, the generation of radicals can cause disproportionation reactions of HFO1123 or HFO1132, which can change HFO1123 and HFO1132 into other compounds.

[0004] Patent Document 3 discloses a refrigeration cycle device that aims to improve the reliability of a refrigeration cycle device that uses a working fluid containing HFO 1123. The refrigeration cycle device disclosed in Patent Document 3 is configured by connecting a compressor equipped with an electric motor, a condenser, an expansion means, and an evaporator in a ring shape to form a refrigeration cycle, and by sealing a working fluid containing an ethylenic fluorohydrocarbon having a double bond in the refrigeration cycle, and is equipped with a protective device that stops the supply of power to the compressor when the current value input to the compressor exceeds a predetermined current value that is set to be three times or more the maximum current value during normal operation other than at startup or two times or more the current value at startup.

[0005] International Publication No. 2012 / 157764 International Publication No. 2012 / 157765 Japanese Patent Application Laid-Open No. 2019-152380

[0006] In a refrigeration cycle (refrigeration cycle circuit), minor discharges may occur in the compressor. In Patent Document 3, the working medium is an ethylene-based fluorohydrocarbon, and such discharges may generate hydrogen fluoride. Hydrogen fluoride has the property of corroding glass, metal, etc., so the presence of hydrogen fluoride in the refrigeration cycle circuit may be one factor in reducing the durability of the refrigeration cycle circuit.

[0007] The present disclosure provides a method for operating a refrigeration cycle circuit, a composition for a refrigeration cycle, a refrigeration cycle device, a control method, and a program that enable improvement in the durability of the refrigeration cycle circuit.

[0008] A method for operating a refrigeration cycle circuit according to one aspect of the present disclosure is a method for operating a refrigeration cycle circuit including a compressor, a condenser, an expansion valve, and an evaporator, and through which a working medium circulates, wherein the working medium includes a refrigerant component capable of producing hydrogen fluoride, and the operating method includes producing hydrogen fluoride from the working medium within the refrigeration cycle circuit, reacting the hydrogen fluoride with a compound represented by formula (1) or formula (2), and circulating the working medium.

[0009]

[0010]

[0011] R in formula (1) １ ~R ４ At least one of R is selected from a hydroxy group, an alkoxy group, or an acyl group; １ ~R ４ The remainder of R is selected from an alkyl group, a vinyl group, an aryl group, a substituent derived from any of these, and a halogeno group. ５ , R ６ is selected from a hydroxy group, an alkoxy group, an acyl group, an alkyl group, a vinyl group, an aryl group, and substituents derived from these groups, and a halogeno group.

[0012] A composition for a refrigeration cycle according to one embodiment of the present disclosure includes a compound represented by formula (1) or formula (2).

[0013] A refrigeration cycle device according to one aspect of the present disclosure includes a refrigeration cycle circuit and the above-described refrigeration cycle composition present in the refrigeration cycle circuit.

[0014] A control method according to one aspect of the present disclosure is a control method executed by a control device that controls a refrigeration cycle circuit including a compressor, a condenser, an expansion valve, and an evaporator, through which a working medium circulates, and a hydrogen fluoride capture mechanism, wherein the working medium includes a refrigerant component capable of generating hydrogen fluoride, and the hydrogen fluoride capture mechanism includes an adsorption tube disposed in the refrigeration cycle circuit and a switching device, wherein the adsorption tube includes a compound represented by Formula (1) or Formula (2) as an adsorbent, and the switching device is capable of switching a path between the compressor and the condenser or the evaporator between a first path that does not pass through the adsorption tube and a second path that passes through the adsorption tube. The control device includes a drive circuit that drives the compressor and a control circuit that controls the drive circuit and the switching device, and the control method switches from the first path to the second path by the switching device in response to detection of an unsteady state of at least one of the compressor and the drive circuit.

[0015] According to one aspect of the present disclosure, there is provided a program executed by a computer system equipped with a control device that controls a refrigeration cycle circuit including a compressor, a condenser, an expansion valve, and an evaporator, through which a working medium circulates, and a hydrogen fluoride capture mechanism, wherein the working medium includes a refrigerant component capable of generating hydrogen fluoride, and the hydrogen fluoride capture mechanism includes an adsorption tube disposed in the refrigeration cycle circuit and a switching device, wherein the adsorption tube includes a compound represented by Formula (1) or Formula (2) as an adsorbent, and the switching device is capable of switching a path between the compressor and the condenser or the evaporator between a first path that does not pass through the adsorption tube and a second path that passes through the adsorption tube. The control device includes a drive circuit that drives the compressor and a control circuit that controls the drive circuit and the switching device. The program causes the computer system to switch from the first path to the second path using the switching device in response to detection of an unsteady state of at least one of the compressor and the drive circuit.

[0016] Aspects of the present disclosure enable improvement in the durability of the refrigeration cycle circuit.

[0017] 1. Schematic diagram of a refrigeration cycle device according to a first embodiment. 2. Block diagram of a refrigeration cycle device according to a first embodiment. 3. Schematic diagram of a compressor and a control device of the refrigeration cycle device according to a first embodiment. 4. Waveform diagram of a voltage of a smoothing circuit of a drive circuit of the control device according to a first embodiment. 5. Part of a flowchart of a method for operating a refrigeration cycle circuit according to a first embodiment. 6. Part of a flowchart of a method for operating a refrigeration cycle circuit according to a first embodiment.

[0018] [1. Embodiments] Hereinafter, embodiments of the present disclosure will be described, with reference to the drawings where appropriate. However, the following embodiments are merely examples for explaining the present disclosure, and are not intended to limit the present disclosure to the following content (e.g., the shape, dimensions, and arrangement of each component). Positional relationships, such as up, down, left, and right, are based on the positional relationships shown in the drawings unless otherwise specified. Each figure described in the following embodiments is a schematic diagram, and the ratios of the size and thickness of each component in each figure do not necessarily reflect the actual dimensional ratios. Furthermore, the dimensional ratios of each element are not limited to the ratios shown in the drawings.

[0019] In the following description, when it is necessary to distinguish between multiple components, prefixes such as "first" and "second" are added to the names of the components. However, when the components can be distinguished from each other by the symbols attached to them, the prefixes such as "first" and "second" may be omitted in consideration of readability of the text.

[0020] [1.1 First Embodiment] [1.1.1 Configuration] Fig. 1 is a schematic diagram of a refrigeration cycle apparatus 1 according to this embodiment. The refrigeration cycle apparatus 1 constitutes, for example, an air conditioner capable of cooling and heating operations. In particular, the refrigeration cycle apparatus 1 is an air conditioner (a so-called package air conditioner (PAC) or a building multi-air conditioner (VRF)) configured such that a single outdoor unit 1a is connected to a plurality of indoor units 1b. In the refrigeration cycle apparatus 1, a hydrogen fluoride capture mechanism 11 is disposed between the outdoor unit 1a and the plurality of indoor units 1b.

[0021] 2 is a schematic diagram of the refrigeration cycle device 1. The refrigeration cycle device 1 includes a refrigeration cycle circuit 2, a hydrogen fluoride capturing mechanism 11, and a control device 3.

[0022] The refrigeration cycle circuit 2 constitutes a flow path through which the working medium 20 (see FIG. 3) circulates. In this embodiment, the working medium 20 contains a refrigerant component capable of generating hydrogen fluoride. The refrigerant component capable of generating hydrogen fluoride may contain an ethylene-based fluoroolefin, in particular, an ethylene-based fluoroolefin that undergoes a disproportionation reaction. Examples of ethylene-based fluoroolefins that undergo a disproportionation reaction include 1,1,2-trifluoroethylene (HFO1123), trans-1,2-difluoroethylene (HFO1132(E)), cis-1,2-difluoroethylene (HFO-1132(Z)), 1,1-difluoroethylene (HFO-1132a), tetrafluoroethylene (CF ２ =CF ２ , FO1114), and monofluoroethylene (HFO-1141).

[0023] The working fluid 20 may contain multiple types of refrigerant components. The working fluid 20 may contain an ethylene-based fluoroolefin as a main refrigerant component and a compound other than an ethylene-based fluoroolefin as a secondary refrigerant component. Examples of the secondary refrigerant component include hydrofluorocarbons (HFCs), hydrofluoroolefins (HFOs), saturated hydrocarbons, carbon dioxide, etc. Examples of hydrofluorocarbons (HFCs) include difluoromethane, difluoroethane, trifluoroethane, tetrafluoroethane, pentafluoroethane, pentafluorobutane, heptafluorocyclopentane, etc. Examples of hydrofluoroolefins (HFOs) include monofluoropropene, trifluoropropene, tetrafluoropropene, pentafluoropropene, hexafluorobutene, etc. Examples of saturated hydrocarbons include ethane, n-propane, cyclopropane, n-butane, cyclobutane, isobutane (2-methylpropane), methylcyclopropane, n-pentane, isopentane (2-methylbutane), neopentane (2,2-dimethylpropane), methylcyclobutane, and the like.

[0024] The working fluid 20 may further contain a disproportionation inhibitor that suppresses the disproportionation reaction of the ethylene-based fluoroolefin. Examples of disproportionation inhibitors include saturated hydrocarbons or haloalkanes. Examples of saturated hydrocarbons include ethane, n-propane, cyclopropane, n-butane, cyclobutane, isobutane (2-methylpropane), methylcyclopropane, n-pentane, isopentane (2-methylbutane), neopentane (2,2-dimethylpropane), methylcyclobutane, and the like. Of the above examples, n-propane is preferred. Examples of haloalkanes include haloalkanes having one or two carbon atoms. Examples of haloalkanes having one carbon atom (i.e., halomethanes) include (mono)iodomethane (CH ３ I), diiodomethane (CH ２ I ２ ), dibromomethane (CH ２ Br ２ ), bromomethane (CH ３ Br), dichloromethane (CH ２ Cl ２), chloroiodomethane (CH ２ ClI), dibromochloromethane (CHBr ２ Cl), tetraiodomethane (Cl ４ ), carbon tetrabromide (CBr ４ ), bromotrichloromethane (CBrCl ３ ), dibromodichloromethane (CBr ２ Cl ２ ), tribromofluoromethane (CBr ３ F), fluorodiiodomethane (CHFI ２ ), difluorodiiodomethane (CF ２ I ２ ), dibromodifluoromethane (CBr ２ F ２ ), trifluoroiodomethane (CF ３ Examples of haloalkanes having two carbon atoms (i.e., haloethanes) include 1,1,1-trifluoro-2-iodoethane (CF ３ CH ２ I), monoiodoethane (CH ３ CH ２ I), monobromoethane (CH ３ CH ２ Br), 1,1,1-triiodoethane (CH ３ CI ３ The working fluid 20 may contain one or more types of haloalkanes having 1 or 2 carbon atoms. That is, only one type of haloalkane having 1 or 2 carbon atoms may be used, or two or more types may be used in appropriate combination.

[0025] The refrigeration cycle circuit 2 includes a compressor 4 , a first heat exchanger 5 , an expansion valve 6 , a plurality of second heat exchangers 7 , a four-way valve 8 , and an accumulator 9 .

[0026] The refrigeration cycle apparatus 1 includes an outdoor unit 1a and multiple indoor units 1b. The outdoor unit 1a includes a control device 3, a compressor 4, a first heat exchanger 5, an expansion valve 6, and a four-way valve 8. The outdoor unit 1a further includes a first blower 5a for promoting heat exchange in the first heat exchanger 5. Each indoor unit 1b includes a second heat exchanger 7. Each indoor unit 1b further includes a second blower 7a for promoting heat exchange in the second heat exchanger 7. The multiple indoor units 1b are connected in parallel to the outdoor unit 1a.

[0027] In the refrigeration cycle circuit 2, the compressor 4 compresses the working medium 20 to increase the pressure of the working medium 20. The compressor 4 will be described in detail later. The first heat exchanger 5 and the second heat exchanger 7 exchange heat between the working medium 20 circulating through the refrigeration cycle circuit 2 and external air (e.g., outside air or room air). The expansion valve 6 adjusts the pressure (evaporation pressure) of the working medium 20 and the flow rate of the working medium 20. The four-way valve 8 switches the direction of the working medium 20 circulating through the refrigeration cycle circuit 2 between a first direction corresponding to cooling operation and a second direction corresponding to heating operation.

[0028] In this embodiment, the first direction is the direction in which the working medium 20 circulates through the refrigeration cycle circuit 2 in the order of the compressor 4, the four-way valve 8, the first heat exchanger 5, the expansion valve 6, the plurality of second heat exchangers 7, the four-way valve 8, and the accumulator 9, as shown by the solid arrow A1 in Figures 1 and 2.

[0029] In cooling operation, the compressor 4 compresses and discharges the gaseous working medium 20, which is then sent to the first heat exchanger 5 via the four-way valve 8. The first heat exchanger 5 exchanges heat between the outside air and the gaseous working medium 20, causing the gaseous working medium 20 to condense and liquefy. The liquid working medium 20 is decompressed by the expansion valve 6 and sent to the second heat exchanger 7. In the second heat exchanger 7, heat exchange occurs between the liquid working medium 20 and the room air, causing the liquid working medium 20 to evaporate and become the gaseous working medium 20. The gaseous working medium 20 returns to the compressor 4 via the four-way valve 8. In cooling operation, the first heat exchanger 5 functions as a condenser, and the second heat exchanger 7 functions as an evaporator. Therefore, during cooling, the indoor unit 1b blows air cooled by heat exchange in the second heat exchanger 7 into the room.

[0030] In this embodiment, the second direction is the direction in which the working medium 20 circulates through the refrigeration cycle circuit 2 in the order of the compressor 4, the four-way valve 8, the second heat exchanger 7, the expansion valve 6, the first heat exchanger 5, and the accumulator 9, as shown by the dashed arrow A2 in Figure 1.

[0031] In heating operation, the compressor 4 compresses and discharges the gaseous working medium 20, which is then sent to the second heat exchanger 7 via the four-way valve 8. The second heat exchanger 7 exchanges heat between the room air and the gaseous working medium 20, causing the gaseous working medium 20 to condense and liquefy. The liquid working medium 20 is decompressed by the expansion valve 6 and sent to the first heat exchanger 5. In the first heat exchanger 5, heat exchange occurs between the liquid working medium 20 and outside air, causing the liquid working medium 20 to evaporate and become the gaseous working medium 20. The gaseous working medium 20 returns to the compressor 4 via the four-way valve 8. In heating operation, the first heat exchanger 5 functions as an evaporator, and the second heat exchanger 7 functions as a condenser. Therefore, during heating, the indoor unit 1b blows air heated by heat exchange in the second heat exchanger 7 into the room.

[0032] The hydrogen fluoride capture mechanism 11 captures hydrogen fluoride within the refrigeration cycle circuit 2. The hydrogen fluoride that the hydrogen fluoride capture mechanism 11 attempts to capture may originate from the working medium 20. That is, when a discharge or the like occurs in the compressor 4, hydrogen fluoride may be generated from the working medium 20. Hydrogen fluoride has the property of corroding glass or metal. By having the hydrogen fluoride capture mechanism 11 capture hydrogen fluoride within the refrigeration cycle circuit 2, the possibility of corrosion of the refrigeration cycle circuit 2 by hydrogen fluoride can be reduced. This enables the durability of the refrigeration cycle circuit 2 to be improved.

[0033] In this embodiment, the hydrogen fluoride capturing mechanism 11 includes an adsorption tube 12 and a switching device 13 .

[0034] The adsorption tube 12 is disposed in the refrigeration cycle circuit 2. This allows the adsorption tube 12 to capture hydrogen fluoride in the refrigeration cycle circuit 2. The adsorption tube 12 contains, as an adsorbent, a composition for a refrigeration cycle that includes a compound represented by formula (1) or formula (2) (hereinafter also referred to as "compound (A)").

[0035] Here, compound (A) has a Si—O bond. Compound (A) is R １ -Si-R ２ R ３ R ４ (see formula (1)) or -[SiR ５ R ６ —O—]— (see formula (2)).

[0036]

[0037] R in formula (1) １ ~R ４ At least one of R is selected from a hydroxy group, an alkoxy group, or an acyl group. １ ~R ４ The remainder of the formula (1) is selected from an alkyl group, a vinyl group, an aryl group, a substituent derived from any of these groups, and a halogeno group. Therefore, examples of the compound (A) having the structure represented by formula (1) include organic silanes and organic silyl ether compounds.

[0038]

[0039] In formula (2), R ５ , R ６ is selected from a hydroxy group, an alkoxy group, an acyl group, an alkyl group, a vinyl group, an aryl group, and a substituent derived from these groups, and a halogeno group. Therefore, examples of the compound (A) having the structure represented by formula (2) include siloxane compounds. ５ , R ６ may be an oxygen atom, in which case silicon is ５ or R ６ to another —O—Si—O unit to form silica.

[0040] Examples of compounds having the structure represented by formula (1) include tetraalkoxysilanes such as tetramethoxysilane. Tetramethoxysilane (Si(OCH ３ ) ４ The reaction of HCl with hydrogen fluoride (HF) is represented by the following formula (3): In formula (3), s indicates a solid and g indicates a gas.

[0041]

[0042] From formula (3), tetramethoxysilane (Si(OCH ３ ) ４ ) and hydrogen fluoride (HF) to produce silicon tetrafluoride (SiF ４ ) and methanol (CH ３ OH) is obtained.

[0043] An example of a compound having a structure represented by formula (2) is silica. Silica (SiO ２ The reaction between HCl and hydrogen fluoride (HF) is expressed by the following equation (4): In equation (4), s indicates a solid, g indicates a gas, and g / l indicates a mixed state of gas and liquid.

[0044]

[0045] From formula (4), silica (SiO ２ ) and hydrogen fluoride (HF) to produce silicon tetrafluoride (SiF ４ ) and water (H ２ O) is obtained.

[0046] Other examples of compounds having the structure represented by formula (2) include silicone oil (siloxane) and silyl ether. Silicone oil has the structure represented by formula (5). Silyl ether has the structure represented by formula (6).

[0047]

[0048] In formula (5), R １ , R ２ is selected from a hydroxy group, an alkoxy group, an acyl group, an alkyl group, a vinyl group, an aryl group, and substituents derived from these groups, and a halogeno group. Therefore, examples of the compound (A) having the structure represented by formula (5) include siloxane compounds.

[0049]

[0050] In formula (6), R １ , R ２ , R ３ , R ４is selected from a hydroxy group, an alkoxy group, an acyl group, an alkyl group, a vinyl group, an aryl group, and substituents derived from these groups, and a halogeno group.

[0051] The reaction between silicone oil and hydrogen fluoride is expressed by formula (7): In formula (7), 1 represents the liquid, g represents the gas, and g / 1 represents a mixed state of the gas and liquid.

[0052]

[0053] The reaction between silyl ether and hydrogen fluoride is represented by formula (8): In formula (8), 1 represents the liquid, g represents the gas, and 1 / g represents the mixed state of the liquid and the gas.

[0054]

[0055] From the formulas (7) and (8), the fluorine-containing Si compound (SiF ２ R １ R ２ Such fluorine-containing Si compounds may be less harmful to glass or metal than hydrogen fluoride.

[0056] The switching device 13 constitutes a part of the refrigeration cycle circuit 2. The switching device 13 is capable of switching between a first route R11 and a second route R12. The first route R11 is a route that does not pass through the adsorption tube 12, and the second route R12 is a route that passes through the adsorption tube 12. In this embodiment, the switching device 13 includes two three-way valves 13a and 13b. The switching device 13 is located between the compressor 4 of the outdoor unit 1a and the second heat exchanger 7 of the indoor unit 1b. During cooling operation, the second heat exchanger 7 functions as an evaporator, and during heating operation, the second heat exchanger 7 functions as a condenser. Therefore, the switching device 13 is capable of switching the route between the compressor 4 and the condenser or evaporator between the first route R11, which does not pass through the adsorption tube 12, and the second route R12, which passes through the adsorption tube 12.

[0057] FIG. 3 is a schematic diagram of the compressor 4 and the control device 3.

[0058] The compressor 4 is, for example, a hermetic compressor. The compressor 4 may be a rotary type, a scroll type, or any other known type. The compressor 4 includes a hermetic container 40, a compression mechanism 41, and an electric motor 42.

[0059] The sealed container 40 forms a flow path for the working medium 20. The sealed container 40 has a suction pipe 401 and a discharge pipe 402. The working medium 20 is sucked into the sealed container 40 from the suction pipe 401, compressed by the compression mechanism 41, and then discharged from the discharge pipe 402 to the outside of the sealed container 40. The inside of the sealed container 40 is filled with the high-temperature and high-pressure working medium 20 and lubricating oil. The bottom of the sealed container 40 forms an oil reservoir that stores a mixture of the working medium 20 and lubricating oil.

[0060] The compression mechanism 41 is located inside the sealed container 40 and compresses the working medium 20. The compression mechanism 41 may have a conventionally known configuration. The compression mechanism 41 has, for example, a cylinder that forms a compression chamber, a rolling piston that is disposed in the compression chamber inside the cylinder, and a crankshaft that is coupled to the rolling piston.

[0061] The electric motor 42 is located inside the sealed container 40 and drives the compression mechanism 41. The electric motor 42 is, for example, a brushless motor (three-phase brushless motor). The electric motor 42 includes, for example, a rotor fixed to the crankshaft of the compression mechanism 41 and a stator disposed around the rotor. The stator is configured, for example, by concentrating or dispersing a stator winding (magnet wire, etc.) around a stator core (electromagnetic steel plate, etc.) with an insulating material such as insulating paper interposed therebetween. The stator winding is covered with an insulating material. Examples of insulating materials include polyethylene terephthalate (PET), polyethylene naphthalate (PEN), aramid polymer, polyphenylene sulfide (PPS), polytetrafluoroethylene (PTFE), etc.

[0062] Accumulator 9 is provided to prevent liquid compression in the compression chambers of compression mechanism 41. Accumulator 9 is located on the suction pipe 401 side of compressor 4. More specifically, accumulator 9 is located between suction pipe 401 of compressor 4 and four-way valve 8. Accumulator 9 separates working medium 20 into gaseous working medium 20 and liquid working medium 20, and introduces only the gaseous working medium 20 from suction pipe 401 into the inside of sealed container 40.

[0063] The control device 3 controls the compressor 4 and the hydrogen fluoride capturing mechanism 11 of the refrigeration cycle circuit 2. The control device 3 includes a drive circuit 31, a state detection circuit 32, a first protection device 33, a second protection device 34, and a control circuit 35.

[0064] Next, the drive circuit 31, the state detection circuit 32, the first protection device 33, the second protection device 34, and the control circuit 35 will be described with reference to FIG.

[0065] The drive circuit 31 drives the electric motor 42 based on input power from the power supply 10. In this embodiment, the power supply 10 is an AC power supply, and the input power is AC power. The drive circuit 31 includes a converter circuit 311 and an inverter circuit 312.

[0066] The converter circuit 311 outputs DC output power based on the input power from the power supply 10 so that the voltage becomes a first voltage. That is, the converter circuit 311 converts the input power into DC output power so that the voltage of the DC output power becomes the first voltage. The first voltage corresponds to the rated voltage of the drive circuit 31.

[0067] The converter circuit 311 includes a rectifier circuit 311a and a smoothing circuit 311b.

[0068] The rectifier circuit 311a is a diode bridge composed of a plurality of diodes D1 to D4. The power supply 10 is connected between the input terminals of the rectifier circuit 311a (the connection point between the diodes D1 and D2 and the connection point between the diodes D3 and D4), and the smoothing circuit 311b is connected between the output terminals of the rectifier circuit 311a (the connection point between the diodes D1 and D3 and the connection point between the diodes D2 and D4).

[0069] The smoothing circuit 311b smoothes and outputs the voltage between the output terminals of the rectifier circuit 311a. The smoothing circuit 311b sets the voltage of the DC output power to a first voltage. The smoothing circuit 311b includes a series circuit of an inductor L1 and smoothing capacitors C1 and C2. In the smoothing circuit 311b, the connection point between the inductor L1 and the smoothing capacitor C1 is a first output point P1 that outputs a voltage corresponding to the first voltage. In the smoothing circuit 311b, the connection point between the diodes D2 and D4 and the smoothing capacitor C2 is a second output point P2 that outputs a voltage lower than the voltage at the first output point P1. In the smoothing circuit 311b, the connection point between the smoothing capacitor C1 and the smoothing capacitor C2 is a third output point P3 that outputs a voltage between the voltage at the first output point P1 and the voltage at the second output point P2. In the relationship between the first output point P1, the second output point P2, and the third output point P3, the first output point P1 is a high-voltage point, the second output point P2 is a low-voltage point, and the third output point P3 is an intermediate-voltage point. In the smoothing circuit 311b, the smoothing capacitors C1 and C2 have the same capacitance. Therefore, the voltage between the first output point P1 and the third output point P3 is equal to the voltage between the second output point P2 and the third output point P3. If the voltage between the first output point P1 and the second output point P2 (which corresponds to the first voltage) is E, the voltage between the first output point P1 and the third output point P3 is E / 2, and similarly, the voltage between the second output point P2 and the third output point P3 is E / 2. This allows the drive circuit 31 to provide five voltage levels: E, E / 2, 0, −E / 2, and −E.

[0070] The inverter circuit 312 outputs AC output power to the electric motor 42 based on the DC output power from the converter circuit 311. In the present embodiment, the AC output power is three-phase AC power. The inverter circuit 312 includes a plurality of semiconductor switching elements U1 to U4, V1 to V4, and W1 to W4. The semiconductor switching elements U1 to U4, V1 to V4, and W1 to W4 are, for example, transistors.

[0071] The semiconductor switching elements U1 to U4, V1 to V4, and W1 to W4 each form a series circuit and are connected between a first output point P1 and a second output point P2.

[0072] The connection point of the semiconductor switching elements U1 and U2, the connection point of the semiconductor switching elements V1 and V2, and the connection point of the semiconductor switching elements W1 and W2 are connected to a third output point P3 via diodes D5, D7, and D9, respectively.

[0073] The anodes of diodes D5, D7, and D9 are connected to the third output point P3, and the cathodes of diodes D5, D7, and D9 are connected to the connection point of semiconductor switching elements U1 and U2, the connection point of semiconductor switching elements V1 and V2, and the connection point of semiconductor switching elements W1 and W2, respectively.

[0074] The connection point of the semiconductor switching elements U2 and U3 forms a U-phase output terminal Pu connected to a U-phase input terminal of the motor 42. The connection point of the semiconductor switching elements V2 and V3 forms a V-phase output terminal Pv connected to a V-phase input terminal of the motor 42. The connection point of the semiconductor switching elements W2 and W3 forms a W-phase output terminal Pw connected to a W-phase input terminal of the motor 42.

[0075] The connection point of the semiconductor switching elements U3 and U4, the connection point of the semiconductor switching elements V3 and V4, and the connection point of the semiconductor switching elements W3 and W4 are connected to a third output point P3 via diodes D6, D8, and D10, respectively.

[0076] The cathodes of diodes D6, D8, and D10 are connected to the third output point P3, and the anodes of diodes D6, D8, and D10 are connected to the connection point of semiconductor switching elements U3 and U4, the connection point of semiconductor switching elements V3 and V4, and the connection point of semiconductor switching elements W3 and W4, respectively.

[0077] In the inverter circuit 312, the semiconductor switching elements U1, U2, V1, V2, W1, and W2 constitute a first semiconductor switching element group connected between the first output point P1 and the electric motor 42. In particular, the semiconductor switching elements U1 and U2 constitute a U-phase first semiconductor switching element group connected between the first output point P1 and the U-phase input terminal of the electric motor 42. The semiconductor switching elements V1 and V2 constitute a V-phase first semiconductor switching element group connected between the first output point P1 and the V-phase input terminal of the electric motor 42. The semiconductor switching elements W1 and W2 constitute a W-phase first semiconductor switching element group connected between the first output point P1 and the W-phase input terminal of the electric motor 42.

[0078] The semiconductor switching elements U3, U4, V3, V4, W3, and W4 constitute a second semiconductor switching element group connected between the second output point P2 and the motor 42. In particular, the semiconductor switching elements U3 and U4 constitute a U-phase second semiconductor switching element group connected between the second output point P2 and a U-phase input terminal of the motor 42. The semiconductor switching elements V3 and V4 constitute a V-phase second semiconductor switching element group connected between the second output point P2 and a V-phase input terminal of the motor 42. The semiconductor switching elements W3 and W4 constitute a W-phase second semiconductor switching element group connected between the second output point P2 and a W-phase input terminal of the motor 42.

[0079] The semiconductor switching elements U2, U3, V2, V3, W2, and W3 constitute a third semiconductor switching element group connected between the third output point P3 and the electric motor 42. In particular, the semiconductor switching elements U2 and U3 constitute a U-phase third semiconductor switching element group connected between the third output point P3 and the U-phase input terminal of the electric motor 42. The semiconductor switching elements V2 and V3 constitute a V-phase third semiconductor switching element group connected between the third output point P3 and the V-phase input terminal of the electric motor 42. The semiconductor switching elements W2 and W3 constitute a W-phase third semiconductor switching element group connected between the third output point P3 and the W-phase input terminal of the electric motor 42.

[0080] The converter circuit 311 has a plurality of output points including first to third output points P1 to P3. The inverter circuit 312 has a plurality of semiconductor switching element groups including a first semiconductor switching element group (semiconductor switching elements U1, U2, V1, V2, W1, W2) connected between the first output point P1 and the motor 42, a second semiconductor switching element group (semiconductor switching elements U3, U4, V3, V4, W3, W4) connected between the second output point P2 and the motor 42, and a third semiconductor switching element group (semiconductor switching elements U2, U3, V2, V3, W2, W3) connected between the third output point P3 and the motor 42. The drive circuit 31 is a so-called multilevel inverter, particularly a three-level inverter.

[0081] The state detection circuit 32 detects the state of at least one of the compressor 4 and the drive circuit 31. In this embodiment, the state detection circuit 32 detects the state of the drive circuit 31. The state of the drive circuit 31 is the voltage of the DC output power of the converter circuit 311. In this embodiment, the state detection circuit 32 is a voltage detector that detects the DC output power of the converter circuit 311 and outputs a detection voltage indicating the voltage of the DC output power. In this embodiment, the state detection circuit 32 includes a voltage divider circuit connected between the output terminals of the smoothing circuit 311b of the converter circuit 311, i.e., between the first output point P1 and the second output point P2, and outputs the detection voltage based on the voltage obtained from the voltage divider circuit. Alternatively, the state detection circuit 32 may output the detection voltage based on the output of the voltage divider circuit and a differential amplifier. As an example, the non-inverting input terminal and the inverting input terminal of the differential amplifier are connected to both ends of a resistor in the voltage divider circuit, respectively, and the differential amplifier can output the voltage across the resistor as the detection voltage. The use of a differential amplifier makes it possible to detect the potential difference in the floating state, thereby improving the accuracy of the detected voltage. The position at which the state detection circuit 32 is connected to the drive circuit 31 is not particularly limited as long as it is at a position at which the DC output power of the converter circuit 311 can be detected. The position at which the DC output power of the converter circuit 311 can be detected is not limited to within the converter circuit 311, but may be at a position within the inverter circuit 312 that is circuit-equivalent to each of the first output point P1 and the second output point P2. A conventionally known configuration can be used for the voltage divider circuit, and therefore a detailed description thereof will be omitted.

[0082] The first protection device 33 is provided to stop the output of AC output power. The first protection device 33 includes switches Su, Sv, and Sw interposed between the drive circuit 31 and the electric motor 42. The switches Su, Sv, and Sw are connected between the U-phase, V-phase, and W-phase input terminals of the electric motor 42 and the U-phase output terminals Pu, Pv, and Pw, respectively. The switches Su, Sv, and Sw may be controllable switches such as semiconductor switches or electromagnetic relays. When the switches Su, Sv, and Sw are closed in an ON state, the first protection device 33 allows the output of AC output power from the drive circuit 31 to the electric motor 42. When the switches Su, Sv, and Sw are open in an OFF state, the first protection device 33 stops the output of AC output power from the drive circuit 31 to the electric motor 42.

[0083] The second protection device 34 is provided to stop the input of input power. The second protection device 34 includes switches S1 and S2 interposed between the drive circuit 31 and the power source 10. The switches S1 and S2 are respectively connected between the input terminal of the rectifier circuit 311a and the power source 10. The switches S1 and S2 may be controllable switches such as semiconductor switches or electromagnetic relays. When the switches S1 and S2 are closed in an on state, the second protection device 34 allows the input of input power from the power source 10 to the drive circuit 31, and when the switches S1 and S2 are open in an off state, the second protection device 34 stops the input of input power from the power source 10 to the drive circuit 31.

[0084] The control circuit 35 can be realized, for example, by a computer system including at least one processor (microprocessor) and one or more memories. The computer system may also include one or more A / D converters. For example, the one or more A / D converters are used to convert the detected voltage from the state detection circuit 32 from analog to digital format. The control circuit 35 controls the drive circuit 31, the first protection device 33, the second protection device 34, and the hydrogen fluoride capture mechanism 11. In particular, the control circuit 35 performs PWM control of a group of semiconductor switching elements in the inverter circuit 312 of the drive circuit 31 so that the drive circuit 31 operates the electric motor 42. More specifically, the control circuit 35 controls the switching of the semiconductor switching elements U1 to U4, V1 to V4, and W1 to W4 in the inverter circuit 312 of the drive circuit 31 so that the inverter circuit 312 supplies AC output power (three-phase AC power) to the electric motor 42 based on the DC output power from the smoothing circuit 311b.

[0085] The semiconductor switching elements U1 to U4 have three states: a first state in which the semiconductor switching elements U1 and U2 are on and the semiconductor switching elements U3 and U4 are off, a second state in which the semiconductor switching elements U3 and U4 are on and the semiconductor switching elements U1 and U2 are off, and a third state in which the semiconductor switching elements U2 and U3 are on and the semiconductor switching elements U1 and U4 are off. The voltage at the U-phase output terminal Pu is E / 2 in the first state, −E / 2 in the second state, and 0 in the third state.

[0086] The semiconductor switching elements V1 to V4 have three states: a first state in which the semiconductor switching elements V1 and V2 are on and the semiconductor switching elements V3 and V4 are off, a second state in which the semiconductor switching elements V3 and V4 are on and the semiconductor switching elements V1 and V2 are off, and a third state in which the semiconductor switching elements V2 and V3 are on and the semiconductor switching elements V1 and V4 are off. The voltage at the V-phase output terminal Pv is E / 2 in the first state, −E / 2 in the second state, and 0 in the third state.

[0087] The semiconductor switching elements W1 to W4 have three states: a first state in which the semiconductor switching elements W1 and W2 are on and the semiconductor switching elements W3 and W4 are off, a second state in which the semiconductor switching elements W3 and W4 are on and the semiconductor switching elements W1 and W2 are off, and a third state in which the semiconductor switching elements W2 and W3 are on and the semiconductor switching elements W1 and W4 are off. The voltage at the W-phase output terminal Pw is E / 2 in the first state, −E / 2 in the second state, and 0 in the third state.

[0088] In this way, the drive circuit 31 can provide voltages at five levels: E, E / 2, 0, −E / 2, and −E.

[0089] The control circuit 35 controls the switching of the semiconductor switching elements U1 to U4, V1 to V4, and W1 to W4 of the inverter circuit 312 of the drive circuit 31 based on, for example, U-phase, V-phase, and W-phase output voltage command values ​​corresponding to the sinusoidal AC voltages of the U-phase, V-phase, and W-phase of the three-phase AC, respectively, and on the basis of first and second carrier triangular waves. The value of the first carrier triangular wave is equal to or greater than 0, and the value of the second carrier triangular wave is equal to or less than 0. The drive circuit 31 can apply five voltage levels, E, E / 2, 0, −E / 2, and −E, thereby making the voltage between the U-phase input terminal and the V-phase input terminal of the motor 42, the voltage between the V-phase input terminal and the W-phase input terminal of the motor 42, and the voltage between the W-phase input terminal and the U-phase input terminal of the motor 42 each closer to a sine wave.

[0090] The control circuit 35 further executes processing to protect the refrigeration cycle circuit 2 based on the detected voltage from the state detection circuit 32 .

[0091] The causes of the disproportionation reaction of the working medium 20 are thought to be heat and radicals. For example, it is thought that the disproportionation reaction of the working medium 20 progresses when radicals are generated under high temperature and high pressure. When the disproportionation reaction of the working medium 20 progresses, hydrogen fluoride may be generated from the working medium 20. The radicals may be generated, for example, by a discharge phenomenon that may occur when some unsteady state different from the steady state occurs in the compressor 4 or the drive circuit 31.

[0092] The inventors discovered that when a discharge occurs in the compressor 4, a sudden change occurs in the voltage of the DC output power of the converter circuit 311, i.e., the voltage of the smoothing circuit 311b of the drive circuit 31. FIG. 4 is a waveform diagram of the voltage of the DC output power of the converter circuit 311. In FIG. 4, the voltage of the DC output current gradually decreases from time t11 to t12, t21 to t22, t31 to t32, t41 to t42, and t51 to t52. This voltage decrease is due to the switching of the semiconductor switching elements U1 to U4, V1 to V4, and W1 to W4 of the inverter circuit 312. If the switching frequency of the inverter circuit 312 is, for example, 1.0 kHz to 5.0 kHz, the time between time t11 and time t21 is approximately 0.2 to 1.0 ms. At time t33, a sudden drop in the voltage of the DC output current is observed, which is believed to be due to the occurrence of a discharge phenomenon.

[0093] From this perspective, the control circuit 35 determines whether a discharge phenomenon has occurred based on the detected voltage from the state detection circuit 32, and if it determines that a discharge phenomenon has occurred, it switches from the first route R11 to the second route R12 using the switching device 13 in order to capture the hydrogen fluoride generated from the working medium 20 circulating through the refrigeration cycle circuit 2.

[0094] The control device 3 detects a sign of a disproportionation reaction based on a change in the DC output power (voltage of the smoothing circuit 311b) inside the drive circuit 31, rather than a change in the current actually flowing from the drive circuit 31 to the electric motor 42. The time scale of the discharge phenomenon is shorter than the time scale of smoothing (rectification) in the drive circuit 31. For example, the time scale of the discharge phenomenon is on the order of μs. Therefore, whether a discharge phenomenon is occurring can be determined based on the DC output power inside the drive circuit 31. Furthermore, measurement of the DC output power (voltage of the smoothing circuit 311b) inside the drive circuit 31 can be performed in a shorter time and at a shorter cycle than measurement of the current actually flowing from the drive circuit 31 to the electric motor 42. This enables earlier detection of a sign of a disproportionation reaction of the working fluid 20. If a sign of a disproportionation reaction of the working fluid 20 can be detected earlier in this way, the disproportionation reaction can be suppressed earlier, thereby improving the suppression of the disproportionation reaction.

[0095] In this embodiment, the control circuit 35 switches from the first path R11 to the second path R12 using the switching device 13 when the detected voltage falls below a second voltage that is equal to or less than the first voltage. The second voltage is set to determine whether a discharge phenomenon has occurred, which may occur when some unsteady state occurs in the compressor 4 or the drive circuit 31. Referring to FIG. 4 , if the normal voltage (first voltage) of the DC output current is E, it has been observed that the voltage of the DC output current falls below 0.8E, or even below 0.3E, due to a discharge phenomenon. From this perspective, the second voltage is preferably between 0.3 and 0.8 times the first voltage. In this embodiment, the second voltage is 0.8 times the first voltage.

[0096] The control circuit 35 switches from the first route R11 to the second route R12 using the switching device 13, thereby capturing hydrogen fluoride that may be generated in the refrigeration cycle circuit 2 using the adsorption tube 12. This suppresses a decrease in durability due to corrosion of the refrigeration cycle circuit 2 caused by hydrogen fluoride circulating within the refrigeration cycle circuit 2, and enables an improvement in the durability of the refrigeration cycle circuit 2.

[0097] When the detected voltage becomes lower than a second voltage that is equal to or lower than the first voltage, the control circuit 35 stops or restricts the operation of the refrigeration cycle circuit 2 in addition to switching the switching device 13 from the first path R11 to the second path R12.

[0098] Stopping or limiting the operation of the refrigeration cycle circuit 2 may include stopping the operation of the drive circuit 31, increasing the rotation speed of the condenser fan, decreasing the rotation speed of the evaporator fan, increasing the opening of the expansion valve, (if the refrigeration cycle device 1 has multiple indoor units 1b) opening the expansion valve of at least one of the indoor units 1b that are not operating, and (in the case of heating operation) switching to cooling operation using the four-way valve 8 and opening the expansion valve 6.

[0099] The operation of the drive circuit 31 can be stopped by stopping the output of AC output power, stopping the output of DC output power, or stopping the input of input power. The operation of the drive circuit 31 can be limited by reducing the set value of the amplitude of the AC output power or reducing the set value of the frequency of the AC output power.

[0100] In this embodiment, the control circuit 35 sets the first protection device 33 to the OFF state to electrically isolate the electric motor 42 from the drive circuit 31 and stop the output of AC output power. To resume the output of AC output power, the control circuit 35 sets the first protection device 33 to the ON state to connect the electric motor 42 to the drive circuit 31.

[0101] In this embodiment, control circuit 35 controls drive circuit 31 to reduce the set value of the amplitude of the AC output power. In this embodiment, drive circuit 31 can apply five levels of voltage: E, E / 2, 0, −E / 2, and −E, and therefore changes the set value of the amplitude of the AC output power from E to E / 2. In this case, the rotation speed of motor 42 decreases compared to when the set value of the amplitude of the AC output power is E.

[0102] When the input of input power is stopped, the output of AC output power is stopped as a result. In this embodiment, the control circuit 35 sets the second protection device 34 to the OFF state to electrically isolate the power supply 10 from the drive circuit 31 and stop the output of AC output power. When the input of input power is resumed, the control circuit 35 sets the second protection device 34 to the ON state to connect the power supply 10 to the drive circuit 31.

[0103] The control circuit 35 stops or limits the operation of the refrigeration cycle circuit 2 in different ways depending on the number of times the detected voltage falls below the second voltage. In particular, the control circuit 35 executes processing to suppress the disproportionation reaction to a higher degree as the number of times the detected voltage falls below the second voltage increases. This enables the control device 3 to suppress the disproportionation reaction even when relatively minor discharge phenomena occur consecutively within a short period of time. For example, this prevents the disproportionation reaction from being induced beyond a predetermined energy due to consecutive occurrences of low-energy unsteady states (discharges), thereby improving the safety of use of the working medium 20.

[0104] The control circuit 35 stops or limits the operation of the refrigeration cycle circuit 2 in different ways depending on the time difference between the first time when the detected voltage first becomes less than the second voltage and the second time when the detected voltage next becomes less than the second voltage. In particular, the control circuit 35 executes processing that suppresses the disproportionation reaction to a greater extent the shorter the time difference. This enables the control device 3 to suppress the disproportionation reaction even when relatively minor discharge phenomena occur consecutively within a short period of time. This prevents, for example, the disproportionation reaction from being induced beyond a predetermined energy level due to the consecutive occurrence of a low-energy unsteady state (discharge), thereby improving the safety of use of the working medium 20.

[0105] The process for suppressing the disproportionation reaction includes, for example, first to third processes. The first process is a process of stopping the output of AC output power and resuming the output of AC output power after a standby time has elapsed. The second process is a process of stopping the output of AC output power and operating with a reduced set value for the amplitude of the AC output power after a standby time has elapsed. The third process is a process of stopping the output of AC output power and stopping the input of input power. Among the first to third processes, the degree of suppression of the disproportionation reaction increases in the order of the third process, the second process, and the first process. In the first or second process, the longer the standby time, the higher the degree of suppression of the disproportionation reaction.

[0106] Next, an example of an operation method of the refrigeration cycle circuit 2 will be briefly described with reference to Figures 5 to 10. Each of Figures 5 to 10 is a part of a flowchart of the operation method of the refrigeration cycle circuit 2, and Figures 5 to 10 are combined to complete one flowchart.

[0107] See FIG. 5. The control circuit 35 causes the drive circuit 31 to output AC output power to the motor 42 based on the input power of the power supply 10, thereby driving the compressor 4. The control circuit 35 sets the number of times of unsteady states to 0 (S10). The number of times of unsteady states is the number of times an unsteady state has occurred. In this embodiment, the number of times of unsteady states indicates the number of times the detected voltage has become less than the second voltage. A high number of times of unsteady states is an indicator of the likelihood of a disproportionation reaction occurring.

[0108] The control circuit 35 acquires the detected voltage from the state detection circuit 32 (S11). The control circuit 35 determines whether the detected voltage is less than the second voltage (S12).

[0109] If the detected voltage is not less than the second voltage (S12: NO), the process returns to step S10. In steps S11 and S12, the control circuit 35 determines whether the detected voltage is less than the second voltage at a predetermined cycle. The predetermined cycle here is preferably shorter than the cycle corresponding to the reference frequency of the inverter circuit 312 (e.g., 1000 to 5000 Hz).

[0110] If the detected voltage is less than the second voltage in step S12 (S12: YES), the control circuit 35 switches from the first path R11 to the second path R12 using the switching device 13 (S13). This causes the control circuit 35 to capture hydrogen fluoride that may be generated from the working medium 20 in the refrigeration cycle circuit 2 using the hydrogen fluoride capture mechanism 11. Thus, in this embodiment, the operating method includes generating hydrogen fluoride from the working medium 20 in the refrigeration cycle circuit 2, reacting the hydrogen fluoride with compound (A), and circulating the working medium 20. The hydrogen fluoride capture mechanism 11 captures hydrogen fluoride, thereby reducing corrosion of the refrigeration cycle circuit 2 due to hydrogen fluoride, thereby suppressing a decrease in durability of the refrigeration cycle circuit 2. Furthermore, the control circuit 35 increments the number of unsteady states by one (S14) and determines whether the number of unsteady states is equal to or less than one (S15).

[0111] If the number of unsteady states is equal to or less than 1 in step S15 (YES in step S15), the control circuit 35 sets the first protection device 33 to the OFF state to stop the output of AC output power (S16). The control circuit 35 determines whether a first standby time has elapsed since the output of AC output power was stopped (S17). The first standby time is, for example, 1 second. When the first standby time has elapsed (YES in step S17), the control circuit 35 sets the first protection device 33 to the ON state to resume the output of AC output power (S18), switches the switching device 13 from the second path R12 to the first path R11, restarts the operation of the compressor 4, and restarts the operation of the refrigeration cycle circuit 2 (S19). After that, the process returns to step S11.

[0112] In this way, when the detected voltage becomes less than the second voltage, the control circuit 35 switches from the first path R11 to the second path R12 using the switching device 13, and circulates the working medium 20 so that the hydrogen fluoride is captured by the compound (A) that is reactive with hydrogen fluoride within the refrigeration cycle circuit 2. In this way, the operating method includes generating hydrogen fluoride from the working medium 20 within the refrigeration cycle circuit 2, reacting the hydrogen fluoride with the compound (A), and circulating the working medium 20. Furthermore, the control circuit 35 stops outputting the AC output power. The control circuit 35 resumes outputting the AC output power when a first standby time has elapsed since the output of the AC output power was stopped.

[0113] If the number of non-steady states is not equal to or less than 1 in step S15 (S15: NO), referring to FIG. 6, the control circuit 35 determines whether the time difference between the first time when the detected voltage first falls below the second voltage and the second time when the detected voltage next falls below the second voltage is within a first predetermined time (step S20). A short time difference is an indicator of the likelihood of a disproportionation reaction occurring. The first predetermined time is, for example, approximately 100 times the period corresponding to the reference frequency of the inverter circuit 312, or approximately 20 to 100 ms.

[0114] If the time difference is within the first predetermined time in step S20 (step S20: YES), the control circuit 35 turns off the first protection device 33 to stop the output of AC output power (S21). The control circuit 35 turns off the second protection device 34 to stop the input of input power (S22). The control circuit 35 outputs a first unsteady state notification (S23). The first unsteady state notification indicates that an unsteady state in which a disproportionation reaction is highly likely to occur is occurring in the refrigeration cycle apparatus 1. The first unsteady state notification is output to, for example, the control circuit and remote controller of the indoor unit 1b. Thereafter, the control circuit 35 stops operation of the compressor 4 and stops operation of the refrigeration cycle circuit 2 (S24).

[0115] In this way, if the detected voltage becomes less than the second voltage (S20: YES) before a predetermined time (first predetermined time) has elapsed since the output of AC output power was resumed after the first waiting time had elapsed (S18), the control circuit 35 stops the output of AC output power (S21) and stops the input of input power (S22).

[0116] If the time difference is not within the first predetermined time in step S20 (step S20: NO), referring to Fig. 7, the control circuit 35 determines whether the time difference is within a second predetermined time that is longer than the first predetermined time (step S25). The second predetermined time is, for example, about 1000 times the period corresponding to the reference frequency of the inverter circuit 312, and is about 200 ms to 1 s.

[0117] If the time difference is within the second predetermined time in step S25 (step S25: YES), the control circuit 35 sets the first protection device 33 to the OFF state and stops the output of AC output power (S26). The control circuit 35 changes the switching control of the semiconductor switching elements of the drive circuit 31 so that the set value of the amplitude of the AC output power decreases from E to E / 2 (S27). The control circuit 35 outputs a second unsteady state notification (S28). The second unsteady state notification indicates that an unsteady state in which a disproportionation reaction is likely to occur is occurring in the refrigeration cycle apparatus 1. The second unsteady state notification is output to, for example, the control circuit and remote controller of the indoor unit 1b.

[0118] The control circuit 35 determines whether a fourth standby time has elapsed since the output of the AC output power was stopped (S29). The fourth standby time is longer than the first standby time. The fourth standby time is, for example, 60 seconds. When the fourth standby time has elapsed (S29: YES), as shown in FIG. 8 , the control circuit 35 sets the first protection device 33 to the ON state to resume the output of the AC output power (S30), switches the switching device 13 from the second path R12 to the first path R11, resumes operation of the compressor 4, and resumes operation of the refrigeration cycle circuit 2 (S31). In this case, the set value of the amplitude of the AC output power remains lowered from E to E / 2.

[0119] In this way, if the detected voltage becomes less than the second voltage before a predetermined time (second predetermined time) has elapsed since the output of the AC output power was resumed after the first standby time (S18), the control circuit 35 stops the output of the AC output power (S26) and reduces the set value of the amplitude of the AC output power (S27).If a fourth standby time longer than the first standby time has elapsed since the output of the AC output power was stopped, the control circuit 35 resumes the output of the AC output power while keeping the set value of the amplitude of the AC output power reduced (S30).

[0120] Thereafter, the control circuit 35 acquires the detected voltage from the state detection circuit 32 (S32), and determines whether the detected voltage is less than the second voltage (S33).

[0121] In step S33, if the detected voltage is lower than the second voltage (S33: YES), the control circuit 35 switches from the first route R11 to the second route R12 using the switching device 13 (S34), and proceeds to step S20 in FIG.

[0122] In step S33, if the detected voltage is not less than the second voltage (S33: NO), the control circuit 35 determines whether the second monitoring time has elapsed since the operation of the compressor 4 was restarted (S35).

[0123] In step S35, if the second monitoring time has elapsed since the operation of the compressor 4 was restarted (S35: YES), the control circuit 35 cancels the reduction in the set value of the amplitude of the AC output power, returns the set value of the amplitude of the AC output power to E (S36), and proceeds to step S11 in FIG. 5.

[0124] In step S35, if the second monitoring time has not elapsed since the operation of the compressor 4 was restarted (S35: NO), the process returns to step S32.

[0125] In steps S32 to S34, if the detected voltage becomes less than the second voltage between the time when the compressor 4 restarts operation and the time when the second monitoring time has elapsed, the process proceeds to step S21 in FIG. 6, and if the detected voltage does not become less than the second voltage between the time when the compressor 4 restarts operation and the time when the second monitoring time has elapsed, the process proceeds to step S36.

[0126] In this way, if the detected voltage does not become less than the second voltage during the second monitoring time from when the output of AC output power is resumed after the fourth waiting time has elapsed (S30) (YES at S35), the control circuit 35 cancels the reduction of the set value of the amplitude of the AC output power (S36). If the detected voltage becomes less than the second voltage before the second monitoring time has elapsed from when the output of AC output power is resumed after the fourth waiting time has elapsed (S30) (YES at S33), the control circuit 35 stops the output of AC output power (S21) and stops the input of input power (S22).

[0127] 7, if the time difference is not within the second predetermined time in step S25 (step S25: NO), referring to Fig. 9, the control circuit 35 determines whether the time difference is within a third predetermined time, which is longer than the second predetermined time (step S37). The third predetermined time is, for example, about 10,000 times the period corresponding to the reference frequency of the inverter circuit 312, which is about 2 seconds to 10 seconds.

[0128] In step S37, if the time difference is not within the third predetermined time (step S37: NO), the process returns to step S10, and the control circuit 35 sets the number of times of unsteady state to 0 (see FIG. 5). In other words, if a sufficient amount of time has passed since the detection of the unsteady state, the possibility of the occurrence of a discharge phenomenon is considered low, and therefore the number of times of unsteady state is reset to 0.

[0129] In step S37, if the time difference is within the third predetermined time (step S37: YES), the control circuit 35 determines whether the number of times of non-steady state is 2 or less (S38).

[0130] If the number of unsteady states is two or less in step S38 (S38: YES), the control circuit 35 sets the first protection device 33 to the OFF state and stops the output of AC output power (S39). The control circuit 35 outputs a third unsteady state notification (S40). The third unsteady state notification indicates that an unsteady state in which a disproportionation reaction may occur is occurring in the refrigeration cycle apparatus 1. The third unsteady state notification is output to, for example, the control circuit of the indoor unit 1b and a remote controller. The control circuit 35 determines whether a second standby time has elapsed since the output of AC output power was stopped (S41). The second standby time is longer than the first standby time. The second standby time is, for example, 10 seconds. When the second standby time has elapsed (S41: YES), the control circuit 35 sets the first protection device 33 to the ON state to resume output of AC output power (S42), switches the switching device 13 from the second path R12 to the first path R11, resumes operation of the compressor 4, and resumes operation of the refrigeration cycle circuit 2 (S43). After that, the process returns to step S11.

[0131] In this way, when the detected voltage becomes less than the second voltage before a predetermined time (third predetermined time) has elapsed since the resumption of output of AC output power after the first standby time (S18), the control circuit 35 switches from the first path R11 to the second path R12 using the switching device 13, and circulates the working medium 20 so that hydrogen fluoride is captured by compound (A) in the refrigeration cycle circuit 2. In this way, the operating method includes generating hydrogen fluoride from the working medium 20 in the refrigeration cycle circuit 2, reacting the hydrogen fluoride with compound (A), and circulating the working medium 20. Furthermore, the control circuit 35 stops output of AC output power. The control circuit 35 resumes output of AC output power when a second standby time longer than the first standby time has elapsed since the stop of output of AC output power (S42).

[0132] In step S38, if the number of times the unsteady state has occurred is not two or less (S38: NO), that is, if the number of times the unsteady state has occurred is three or more, the control circuit 35 sets the first protection device 33 to the off state to stop the output of AC output power (S44). The control circuit 35 changes the switching control of the semiconductor switching elements of the drive circuit 31 so that the set value of the amplitude of the AC output power decreases from E to E / 2 (S45). The control circuit 35 outputs a second unsteady state notification (S46).

[0133] The control circuit 35 determines whether a third standby time has elapsed since the output of the AC output power was stopped (S47). The third standby time is longer than the second standby time. The third standby time is, for example, 60 seconds. When the third standby time has elapsed (S47: YES), as shown in FIG. 10 , the control circuit 35 sets the first protection device 33 to the ON state to resume the output of the AC output power (S48), switches the switching device 13 from the second path R12 to the first path R11, resumes operation of the compressor 4, and resumes operation of the refrigeration cycle circuit 2 (S49). In this case, the set value of the amplitude of the AC output power remains lowered from E to E / 2.

[0134] In this manner, when the detected voltage becomes less than the second voltage before a predetermined time (third predetermined time) has elapsed since the resumption of output of AC output power after the second standby time (S42), the control circuit 35 switches from the first path R11 to the second path R12 using the switching device 13, and circulates the working medium 20 so that hydrogen fluoride is captured by compound (A) in the refrigeration cycle circuit 2. In this manner, the operating method includes generating hydrogen fluoride from the working medium 20 in the refrigeration cycle circuit 2, reacting the hydrogen fluoride with compound (A), and circulating the working medium 20. Furthermore, the control circuit 35 stops output of the AC output power (S44) and reduces the set value of the amplitude of the AC output power (S45). When a third standby time, which is longer than the second standby time, has elapsed since the stop of output of the AC output power, the control circuit 35 resumes output of the AC output power while maintaining the set value of the amplitude of the AC output power reduced (S48).

[0135] Thereafter, the control circuit 35 acquires the detected voltage from the state detection circuit 32 (S50). The control circuit 35 determines whether the detected voltage is less than the second voltage (S51).

[0136] In step S51, if the detected voltage is lower than the second voltage (S51: YES), the control circuit 35 switches from the first route R11 to the second route R12 by the switching device 13 (S52), and proceeds to step S21 in FIG.

[0137] In step S51, if the detected voltage is not less than the second voltage (S51: NO), the control circuit 35 determines whether the first monitoring time has elapsed since the operation of the compressor 4 was restarted (S53). The first monitoring time may be the same as or different from the second monitoring time in step S35.

[0138] In step S53, if the first monitoring time has elapsed since the operation of the compressor 4 was restarted (S53: YES), the control circuit 35 cancels the reduction in the set value of the amplitude of the AC output power, returns the set value of the amplitude of the AC output power to E (S54), and proceeds to step S11 in FIG. 5.

[0139] In step S53, if the first monitoring time has not elapsed since the operation of the compressor 4 was restarted (S53: NO), the process returns to step S50.

[0140] In steps S50 to S53, if the detected voltage becomes less than the second voltage between the time when the compressor 4 restarts operation and the time when the first monitoring time has elapsed, the process proceeds to step S21 in FIG. 6, and if the detected voltage does not become less than the second voltage between the time when the compressor 4 restarts operation and the time when the first monitoring time has elapsed, the process proceeds to step S54.

[0141] Thus, if the detected voltage does not become less than the second voltage during the first monitoring time period from when the output of AC output power is resumed after the third waiting time period has elapsed (S48) (YES in S53), the control circuit 35 cancels the reduction in the set value of the amplitude of the AC output power (S54). If the detected voltage becomes less than the second voltage during the first monitoring time period from when the output of AC output power is resumed after the third waiting time period has elapsed (S48) (YES in S51), the control circuit 35 switches from the first path R11 to the second path R12 using the switching device 13, and circulates the working medium 20 within the refrigeration cycle circuit 2 so that hydrogen fluoride is captured by the compound (A). Thus, the operating method includes generating hydrogen fluoride from the working medium 20 within the refrigeration cycle circuit 2, reacting the hydrogen fluoride with the compound (A), and circulating the working medium 20. Furthermore, the control circuit 35 stops the output of AC output power (S21) and stops the input of input power (S22).

[0142] [1.1.2 Effects, etc.] The above-described method for operating the refrigeration cycle circuit 2 is a method for operating the refrigeration cycle circuit 2, which includes the compressor 4, the condenser (first heat exchanger 5, second heat exchanger 7), the expansion valve 6, and the evaporator (first heat exchanger 5, second heat exchanger 7), and through which the working medium 20 circulates. The working medium 20 contains a refrigerant component that can produce hydrogen fluoride. The operating method includes producing hydrogen fluoride from the working medium 20 in the refrigeration cycle circuit 2, reacting the hydrogen fluoride with the compound (A) represented by formula (1) or formula (2), and circulating the working medium 20. This configuration enables improvement in the durability of the refrigeration cycle circuit 2.

[0143]

[0144]

[0145] R in formula (1) １ ~R ４ At least one of R is selected from a hydroxy group, an alkoxy group, or an acyl group; １ ~R ４ The remainder of R is selected from an alkyl group, a vinyl group, an aryl group, a substituent derived from any of these, and a halogeno group. ５ , R６ is selected from a hydroxy group, an alkoxy group, an acyl group, an alkyl group, a vinyl group, an aryl group, and substituents derived from these groups, and a halogeno group.

[0146] In a method for operating a refrigeration cycle circuit 2, an adsorption tube 12 is disposed within the refrigeration cycle circuit 2. The adsorption tube 12 contains a compound as an adsorbent. The operating method includes switching a path between the compressor 4 and the condenser or evaporator (second heat exchanger 7) from a first path R11 that does not pass through the adsorption tube 12 to a second path R12 that passes through the adsorption tube 12. This configuration makes it possible to dispose the adsorption tube 12 in the refrigeration cycle circuit 2 only when hydrogen fluoride needs to be captured, thereby reducing the impact on normal operation of the refrigeration cycle circuit 2.

[0147] The operating method of the refrigeration cycle circuit 2 includes switching from the first route R11 to the second route R12 in response to detection of an unsteady state of at least one of the compressor 4 and the drive circuit 31 that drives the compressor 4. This configuration makes it possible to arrange the adsorption tube 12 in the refrigeration cycle circuit 2 only when it is necessary to capture hydrogen fluoride, thereby reducing the impact on normal operation of the refrigeration cycle circuit 2.

[0148] The above-described composition for a refrigeration cycle contains a compound represented by formula (1) or formula (2). This configuration enables the durability of the refrigeration cycle circuit 2 to be improved.

[0149] The refrigeration cycle device 1 described above includes the refrigeration cycle circuit 2 and the refrigeration cycle composition present in the refrigeration cycle circuit 2. This configuration makes it possible to improve the durability of the refrigeration cycle circuit 2.

[0150] The refrigeration cycle apparatus 1 further includes a hydrogen fluoride capture mechanism 11. The refrigeration cycle circuit 2 includes a compressor 4, a condenser (first heat exchanger 5, second heat exchanger 7), an expansion valve 6, and an evaporator (first heat exchanger 5, second heat exchanger 7), and a working medium 20 circulates through the refrigeration cycle circuit 2. The working medium 20 contains a refrigerant component that can generate hydrogen fluoride. The hydrogen fluoride capture mechanism 11 contains a refrigeration cycle composition and captures hydrogen fluoride within the refrigeration cycle circuit 2. This configuration enables the durability of the refrigeration cycle circuit 2 to be improved.

[0151] In the refrigeration cycle device 1, the refrigeration cycle circuit 2 includes a first heat exchanger 5 that functions as an evaporator or a condenser, and a plurality of second heat exchangers 7 that function as condensers when the first heat exchanger 5 functions as an evaporator. The plurality of second heat exchangers 7 are connected in parallel to the first heat exchanger. This configuration enables improvement in the durability of the refrigeration cycle circuit 2.

[0152] In the refrigeration cycle device 1, the hydrogen fluoride capture mechanism 11 includes an adsorption tube 12 disposed in the refrigeration cycle circuit 2, and the adsorption tube 12 contains a refrigeration cycle composition as an adsorbent. This configuration can reduce the influence on the operation of the refrigeration cycle circuit 2.

[0153] In the refrigeration cycle apparatus 1, the hydrogen fluoride capture mechanism 11 includes a switching device 13 that can switch the path between the compressor 4 and the condenser or evaporator (second heat exchanger 7) between a first path R11 that does not pass through the adsorption tube 12 and a second path R12 that passes through the adsorption tube 12. This configuration makes it possible to arrange the adsorption tube 12 in the refrigeration cycle circuit 2 only when it is necessary to capture hydrogen fluoride, thereby reducing the effect on the normal operation of the refrigeration cycle circuit 2.

[0154] The refrigeration cycle apparatus 1 includes a control device 3 that controls the refrigeration cycle circuit 2 and the hydrogen fluoride capture mechanism 11. The control device 3 includes a drive circuit 31 that drives the compressor 4, a state detection circuit 32 that detects the state of at least one of the compressor 4 and the drive circuit 31, and a control circuit 35 that controls the drive circuit 31 and the switching device 13. The control circuit 35 switches from the first path R11 to the second path R12 using the switching device 13 in response to detection of an unsteady state of at least one of the compressor 4 and the drive circuit 31. This configuration makes it possible to arrange the adsorption tube 12 in the refrigeration cycle circuit 2 only when hydrogen fluoride needs to be captured, thereby reducing the impact on normal operation of the refrigeration cycle circuit 2.

[0155] In the refrigeration cycle apparatus 1, the control circuit 35 stops or limits the operation of the refrigeration cycle circuit 2 in response to detection of an unsteady state of at least one of the compressor 4 and the drive circuit 31. This configuration enables improved suppression of the disproportionation reaction of the working medium 20.

[0156] In the refrigeration cycle apparatus 1, the drive circuit 31 includes a converter circuit 311 that outputs DC output power based on input power from the power source 10 so that the voltage becomes a first voltage, and an inverter circuit 312 that outputs AC output power to the compressor 4 based on the DC output power. The state detection circuit 32 detects the DC output power and outputs a detected voltage indicative of the voltage of the DC output power. The unsteady state includes a state in which the detected voltage is less than a second voltage that is equal to or less than the first voltage. This configuration enables earlier detection of a sign of a disproportionation reaction of the working medium 20 and enables improved suppression of the disproportionation reaction of the working medium 20.

[0157] In the refrigeration cycle apparatus 1, the second voltage is 0.3 to 0.8 times the first voltage. This configuration enables the suppression of the disproportionation reaction of the working medium 20 to be improved.

[0158] In the refrigeration cycle device 1, the refrigerant components capable of generating hydrogen fluoride include ethylene-based fluoroolefins that undergo a disproportionation reaction. This configuration enables improved suppression of the disproportionation reaction of the working fluid 20.

[0159] In the refrigeration cycle device 1, the working fluid 20 contains a haloalkane having 1 or 2 carbon atoms as a disproportionation inhibitor that suppresses the disproportionation reaction of ethylene-based fluoroolefins. This configuration enables improved suppression of the disproportionation reaction of the working fluid 20.

[0160] In the refrigeration cycle device 1, the refrigerant components capable of generating hydrogen fluoride are 1,1,2-trifluoroethylene, trans-1,2-difluoroethylene, cis-1,2-difluoroethylene, 1,1-difluoroethylene, tetrafluoroethylene, or monofluoroethylene. This configuration enables improved suppression of the disproportionation reaction of the working fluid 20.

[0161] In the refrigeration cycle device 1, the working fluid 20 further contains difluoromethane as a refrigerant component. This configuration enables the suppression of the disproportionation reaction of the working fluid 20 to be improved.

[0162] In the refrigeration cycle device 1, the working fluid 20 further contains saturated hydrocarbons. This configuration enables the suppression of the disproportionation reaction of the working fluid 20 to be improved.

[0163] In the refrigeration cycle device 1, the saturated hydrocarbons include n-propane. This configuration enables improved suppression of the disproportionation reaction of the working medium 20.

[0164] The control device 3 described above can be said to execute the following control method. The control method is executed by the control device 3, which controls the refrigeration cycle circuit 2, which includes the compressor 4, the condenser (first heat exchanger 5, second heat exchanger 7), the expansion valve 6, and the evaporator (first heat exchanger 5, second heat exchanger 7), and through which the working fluid 20 circulates, and the hydrogen fluoride capture mechanism 11. The working fluid 20 contains a refrigerant component that can generate hydrogen fluoride. The hydrogen fluoride capture mechanism 11 includes an adsorption tube 12 arranged in the refrigeration cycle circuit 2 and a switching device 13. The adsorption tube 12 contains compound (A) as an adsorbent. The switching device 13 is capable of switching the path between the compressor 4 and the condenser or evaporator (second heat exchanger 7) between a first path R11 that does not pass through the adsorption tube 12 and a second path R12 that passes through the adsorption tube 12. The control device 3 includes a drive circuit 31 that drives the compressor 4 and a control circuit 35 that controls the drive circuit 31 and the switching device 13. In the control method, the switching device 13 switches from the first route R11 to the second route R12 in response to detection of an unsteady state of at least one of the compressor 4 and the drive circuit 31. This configuration makes it possible to improve the durability of the refrigeration cycle circuit 2.

[0165] The control method executed by the control device 3 can be realized by a computer system executing a program. The program is executed by a computer system included in the control device 3, which controls a refrigeration cycle circuit 2 including a compressor 4, a condenser (first heat exchanger 5, second heat exchanger 7), an expansion valve 6, and an evaporator (first heat exchanger 5, second heat exchanger 7), through which a working fluid 20 circulates, and a hydrogen fluoride capture mechanism 11. The working fluid 20 contains a refrigerant component capable of generating hydrogen fluoride. The hydrogen fluoride capture mechanism 11 includes an adsorption tube 12 disposed in the refrigeration cycle circuit 2 and a switching device 13. The adsorption tube 12 contains compound (A) as an adsorbent. The switching device 13 is capable of switching the path between the compressor 4 and the condenser or evaporator (second heat exchanger 7) between a first path R11 that does not pass through the adsorption tube 12 and a second path R12 that passes through the adsorption tube 12. The control device 3 includes a drive circuit 31 that drives the compressor 4, and a control circuit 35 that controls the drive circuit 31 and the switching device 13. The program causes the computer system to execute switching from the first path R11 to the second path R12 by the switching device 13 in response to detection of an unsteady state of at least one of the compressor 4 and the drive circuit 31. This configuration enables improvement in durability of the refrigeration cycle circuit 2.

[0166] 11 is a block diagram of a refrigeration cycle apparatus 1A according to this embodiment. The refrigeration cycle apparatus 1A is an air conditioner (a so-called room air conditioner (RAC)) having a configuration in which one outdoor unit 1a is connected to one indoor unit 1b.

[0167] The refrigeration cycle device 1A includes a refrigeration cycle circuit 2A, a hydrogen fluoride capturing mechanism 11A, and a control device 3A.

[0168] The refrigeration cycle circuit 2A includes a compressor 4, a first heat exchanger 5, an expansion valve 6, a second heat exchanger 7, a four-way valve 8, and an accumulator 9. For the compressor 4, the reference numerals in FIG. 3 will be used as necessary.

[0169] The hydrogen fluoride capture mechanism 11A includes an adsorption tube 12 and a switching device 13A.

[0170] The switching device 13A constitutes a part of the refrigeration cycle circuit 2A. The switching device 13A is capable of switching between a first route R11 and a second route R12. The first route R11 is a route that does not pass through the adsorption pipe 12, and the second route R12 is a route that passes through the adsorption pipe 12. In this embodiment, the switching device 13A includes a four-way valve 13c and a three-way valve 13d. The four-way valve 13c is connected to a discharge pipe 402 of the compressor 4. A first output port of the four-way valve 13c is directly connected to the four-way valve 8, and a first route R11 is formed between the four-way valve 13c and the four-way valve 8. A second output port of the four-way valve 13c is connected to the four-way valve 8 via the adsorption pipe 12 and the three-way valve 13d, and a second route R12 is formed between the four-way valve 13c and the four-way valve 8.

[0171] When the second path R12 is formed, the three-way valve 13d is connected to the outlet 14, which is connected to the atmosphere. The outlet 14 releases the working medium 20 into the atmosphere together with products (e.g., silicon tetrafluoride, water, etc.) generated during the capture of hydrogen fluoride. At this time, the concentration of hydrogen fluoride in the working medium is sufficiently reduced, so the toxicity can be reduced when released into the atmosphere. In addition, the pressure loss is lower than when the products generated during the capture of hydrogen fluoride are returned to the refrigeration cycle, so the pressure of the compressor 4 can be reduced quickly.

[0172] As described above, the switching device 13A is located between the discharge pipe 402 of the compressor 4 and the four-way valve 8. The switching device 13A is connected to the first heat exchanger 5 during cooling operation and to the second heat exchanger 7 during heating operation by the four-way valve 8. The first heat exchanger 5 during cooling operation and the second heat exchanger 7 during heating operation both function as condensers. Thus, the switching device 13A is located between the compressor 4 and the condenser. Thus, the switching device 13A can switch the path between the discharge pipe 402 of the compressor 4 and the condenser between a first path R11 that does not pass through the adsorption pipe 12 and a second path R12 that passes through the adsorption pipe 12.

[0173] The control device 3A includes a drive circuit 31, a state detection circuit 32, a first protection device 33, a second protection device 34, and a control circuit 35A. When the detected voltage falls below a second voltage that is equal to or lower than the first voltage, the control circuit 35A switches from the first path R11 to the second path R12 using the switching device 13A. This causes the working medium 20 to circulate within the refrigeration cycle circuit 2A so that hydrogen fluoride is captured by the compound (A) that is reactive with hydrogen fluoride.

[0174] [1.2.2 Effects, etc.] In the refrigeration cycle apparatus 1A described above, the switching device 13A is located between the compressor 4 and the condenser (the first heat exchanger 5 during cooling operation and the second heat exchanger 7 during heating operation). The switching device 13A can switch the path between the discharge pipe 402 of the compressor 4 and the condenser between a first path R11 that does not pass through the adsorption tube 12 and a second path R12 that passes through the adsorption tube 12. This configuration makes it possible to arrange the adsorption tube 12 in the refrigeration cycle circuit 2 only when hydrogen fluoride needs to be captured, thereby reducing the effect on normal operation of the refrigeration cycle circuit 2.

[0175] 12 is a block diagram of a refrigeration cycle apparatus 1B according to this embodiment. The refrigeration cycle apparatus 1B is an air conditioner (a so-called room air conditioner (RAC)) having a configuration in which one outdoor unit 1a is connected to one indoor unit 1b.

[0176] The refrigeration cycle device 1B includes a refrigeration cycle circuit 2B, a hydrogen fluoride capturing mechanism 11B, and a control device 3B.

[0177] The refrigeration cycle circuit 2B includes a compressor 4, a first heat exchanger 5, an expansion valve 6, a second heat exchanger 7, a four-way valve 8, and an accumulator 9. For the compressor 4, the reference numerals in FIG. 3 will be used as necessary.

[0178] Hydrogen fluoride capture mechanism 11B is configured using compressor 4. More specifically, compound (A) of hydrogen fluoride capture mechanism 11B is silicone oil. Silicone oil is dissolved in refrigeration oil of compressor 4. As a result, in the present embodiment, compressor 4 functions as hydrogen fluoride capture mechanism 11B.

[0179] The hydrogen fluoride capture mechanism 11B described above contains a compound (A) (silicone oil in this embodiment) that is reactive with hydrogen fluoride, and captures hydrogen fluoride within the refrigeration cycle circuit 2B. Therefore, when the working fluid 20 circulates through the refrigeration cycle circuit 2B, the hydrogen fluoride within the refrigeration cycle circuit 2B is captured by the silicone oil dissolved in the refrigeration oil of the compressor 4.

[0180] Therefore, in the method of operating the refrigeration cycle circuit 2B, the working medium 20 is circulated in the refrigeration cycle circuit 2B so that the hydrogen fluoride is captured by the compound (A) having reactivity with hydrogen fluoride.

[0181] Silicone oil has a kinematic viscosity of 20 to 100 mm at 40°C. ２ Preferably, the silicone oil has compatibility with polyvinyl ether or polyol ester synthetic oil, which can reduce the influence of the silicone oil on the operation of the refrigeration cycle circuit 2B.

[0182] In this embodiment, silicone oil is dissolved in the refrigeration oil of the compressor 4. Therefore, the silicone oil can circulate through the refrigeration cycle circuit 2B together with the working medium 20. If a semiconductor gas detector is used to detect leaks in the refrigeration cycle device 1B, the silicone oil may reduce the sensitivity of the gas detector. Therefore, it is preferable to use a non-dispersive infrared (NDIR) type, catalytic combustion type, or electrochemical type gas detector to detect leaks of the working medium 20. This is expected to improve the accuracy of detecting leaks of the working medium 20.

[0183] The control device 3B includes a drive circuit 31, a state detection circuit 32, a first protection device 33, a second protection device 34, and a control circuit 35B. The control circuit 35B stops or limits the operation of the refrigeration cycle circuit 2 in response to detection of an unsteady state of at least one of the compressor 4 and the drive circuit 31.

[0184] [1.3.2 Effects, etc.] In the above-described method for operating the refrigeration cycle circuit 2B, the compound (A) is silicone oil. The silicone oil is dissolved in the refrigeration oil of the compressor 4. This configuration makes it possible to capture hydrogen fluoride without changing the configuration of the refrigeration cycle circuit 2B.

[0185] In the operation method of the refrigeration cycle circuit 2B, the silicone oil has a kinematic viscosity of 20 to 100 mm at 40°C. ２ / s, and is compatible with polyvinyl ether or polyol ester synthetic oil. This configuration makes it possible to capture hydrogen fluoride while reducing the influence on the operation of the refrigeration cycle circuit 2B.

[0186] In the refrigeration cycle apparatus 1B described above, the compound (A) is silicone oil. The silicone oil is dissolved in the refrigeration oil of the compressor 4. This configuration makes it possible to capture hydrogen fluoride without changing the configuration of the refrigeration cycle circuit 2B.

[0187] [2. Modifications] The embodiments of the present disclosure are not limited to the above-described embodiments. The above-described embodiments can be modified in various ways depending on the design, etc., as long as the object of the present disclosure can be achieved. Modifications of the above-described embodiments are listed below. The modifications described below can be applied in appropriate combinations.

[0188] In the following, although the symbols used in the first embodiment are applicable to any of the above-mentioned first to third embodiments, this is merely to simplify the description and is not intended to exclude application to the second and third embodiments.

[0189] In one modification, the configuration of the suction tube 12 is not limited to the above embodiment.

[0190] FIG. 13 is a schematic diagram of an adsorption tube 12C according to a modified example. The adsorption tube 12C uses a solid compound (A), for example, a compound (A) that solidifies at 150°C or below. The adsorption tube 12C includes a tube 1210, diffusion layers 1211 and 1212, and an adsorption layer 1213. The tube 1210 is, for example, cylindrical, and has an inlet 1210a through which the working medium flows and an outlet 1210b through which the working medium flows, respectively, at both ends. Inside the tube 1210, the diffusion layer 1211, the adsorption layer 1213, and the diffusion layer 1212 are arranged in this order from the inlet 1210a toward the outlet 1210b. The diffusion layers 1211 and 1212 are composed of a plurality of balls that diffuse the working medium. The balls may be coarse balls, for example, ceramic balls of approximately 1 / 4 to 1 inch. The adsorption layer 1213 contains the compound (A). The adsorption layer 1213 is formed by immobilizing the compound (A) on a carrier (support). As an example, the adsorption layer 1213 can be obtained by impregnating a non-silica porous ceramic carrier with a solvent containing the compound (A) and drying the impregnated ceramic carrier. The adsorption layer 1213 may also support a hydrogen fluoride trapping agent that captures hydrogen fluoride.

[0191] FIG. 14 is a schematic diagram of an adsorption tube 12D according to a modified example. The adsorption tube 12D uses a solid compound (A), for example, a compound (A) that solidifies at 150°C or below. The adsorption tube 12D includes a tube 1220 and multiple adsorbents 1221. The tube 1220 is, for example, cylindrical, and has an inlet 1220a through which the working medium flows and an outlet 1220b through which the working medium flows, respectively, at both ends. Multiple adsorbents 1221 are arranged inside the tube 1220 from the inlet 1220a toward the outlet 1220b. The adsorbents 1221 contain the compound (A). The adsorbents 1221 are formed by fixing the compound (A) to a carrier (support). As an example, the adsorbents 1221 can be obtained by impregnating a (thick) plate-shaped porous material holder as a carrier with a solution containing the compound (A) and then drying the resulting solution. The adsorbent 1221 can be obtained by impregnating a glass fiber filter as a carrier with a solvent containing the compound (A) and drying it. The adsorbent 1221 may also support a hydrogen fluoride trapping agent that captures hydrogen fluoride.

[0192] FIG. 15 is a schematic diagram of an adsorption tube 12E according to a modified example. The adsorption tube 12E employs a solution containing a compound (A). The solution containing the compound (A) may be a solution in which a liquid compound (A) or a solid compound (A) is dispersed. The adsorption tube 12E includes a pipe 1230, a tank 1231, and a spray device 1232. The pipe 1230 is, for example, cylindrical and has an inlet 1230a through which the working medium flows and an outlet 1230b through which the working medium flows, respectively, at both ends. The tank 1231 stores a solution 1233 containing the compound (A) and refrigerating machine oil. The spray device 1232 sprays the solution 1233 containing the compound (A) and refrigerating machine oil from the tank 1231 into the pipe 1230. A portion of the solution 1233 sprayed from the spray device 1232 into the pipe 1230 remains in the pipe 1230 and returns to the tank 1231 via a passage 1234 connecting the pipe 1230 and the tank 1231. The spray device 1232 can include, for example, a suction nozzle, in which case a power source such as a pump is not required.

[0193] FIG. 16 is a schematic diagram of an adsorption tube 12F according to a modified example. The adsorption tube 12F employs a solution containing compound (A). The solution containing compound (A) may be a solution in which liquid compound (A) or solid compound (A) is dispersed. The adsorption tube 12E includes a tube 1240, a trap 1241, a gas-liquid separation membrane 1242, and filters 1243 and 1244. The tube 1240 is cylindrical and has an inlet 1240a for the working medium, to which the trap 1241 is connected via a connecting tube 1240b. The gas-liquid separation membrane 1242 is located within the tube 1240 between the inlet 1240a and the connecting tube 1240b. The gas-liquid separation membrane 1242 allows the working medium 1245 to pass through. The trap 1241 has a liquid return tube 1241a and an outlet 1241b through which the working medium flows out. Filters 1243 and 1244 are disposed within trap 1241. Filter 1243 is located between connecting pipe 1240b and liquid return pipe 1241a, and filter 1244 is located between connecting pipe 1240b and outlet 1241b. Filters 1243 and 1244 separate the working medium from compound (A). Trap 1241 receives working medium 1245 containing droplets of compound (A) from connecting pipe 1240b, separates solution 1246 from working medium 1245 using filters 1243 and 1244, and discharges only working medium 1245 from outlet 1241b. To prevent the solution 1246 in pipe 1240 from being depleted, the solution 1246 separated within trap 1241 is returned to pipe 1240 through liquid return pipe 1241a. In this manner, the solution 1246 circulates between the tube 1240 and the trap 1241 .

[0194] In one modified example, the configuration of the switching device 13 is not limited to the above embodiment. For example, the switching device 13 can be configured using various valves and pipes other than a three-way valve or a four-way valve, as long as the second route R12 can be switched as a bypass for the first route R11.

[0195] In one modified example, in the control circuit 35, stopping the operation of the drive circuit 31 may include one or more of stopping the output of AC output power, stopping the output of DC output power, or stopping the input of input power. Restricting the operation of the drive circuit 31 may include one or more of reducing the set value of the amplitude of the AC output power or reducing the set value of the frequency of the AC output power.

[0196] In one modified example, the control circuit 35 may stepwise stop or decelerate the electric motor 42. As an example, the control circuit 35 may stepwise reduce at least one of the amplitude and frequency of the AC output power, thereby stepwise reducing the effective value of the AC output power supplied to the electric motor 42.

[0197] In this modification, the operation of the control circuit 35 is not necessarily limited to the operations shown in the flowcharts of Figures 5 to 10. The flowcharts of Figures 5 to 10 are merely examples.

[0198] For example, the processing of steps S20 to S24, i.e., the processing of stopping the output of AC output power and stopping the input of input power, is not essential in the operation of the control circuit 35. The processing of steps S25 to S29, i.e., the processing of stopping the output of AC output power and reducing the set value of the amplitude of the AC output power after the standby time has elapsed, is not essential in the operation of the control circuit 35. Similarly, the processing of steps S30 to S36, steps S37 to S43, or steps S42 to S51 is not essential in the operation of the control circuit 35.

[0199] The control circuit 35 does not necessarily have to stop or restrict the operation of the refrigeration cycle circuit 2 in different ways depending on the time difference between the first time when the detected voltage first becomes less than the second voltage and the second time when the detected voltage next becomes less than the second voltage, or the number of times the detected voltage becomes less than the second voltage.

[0200] In one modified example, the first protection device 33 is not limited to a circuit configuration including the switches Su, Sv, and Sw, and may include a circuit configuration that adjusts the magnitude of the AC output power, for example, the magnitude of the voltage, output from the drive circuit 31 to the electric motor 42. The first protection device 33 may be disposed within the drive circuit 31.

[0201] In one modified example, the second protection device 34 is not limited to a circuit configuration including the switches S1 and S2, and may include a circuit configuration that adjusts the magnitude of the input power, for example, the magnitude of the voltage, input from the power source 10 to the drive circuit 31. The second protection device 34 may be disposed within the drive circuit 31.

[0202] In one modified example, the control device 3 does not necessarily include both the first protection device 33 and the second protection device 34, and may include either the first protection device 33 or the second protection device 34, or the first and second protection devices 33, 34 may be omitted if the drive circuit 31 has a function of adjusting the AC output power. For example, the control circuit 35 may stop the output of AC output power to the motor 42 by turning on the semiconductor switching elements V1 to V4 of the inverter circuit 312 and turning off the remaining semiconductor switching elements U1 to U4, W1 to W4. In this case, the first protection device 33 may be omitted.

[0203] FIG. 17 shows a modified control device 3G. In FIG. 17, the control device 3G includes a third protection device 37. The third protection device 37 is provided to stop the output of DC output power. The third protection device 37 includes switches S3, S4, and S5 interposed between the converter circuit 311 and the inverter circuit 312 of the drive circuit 31. The switch S3 is commonly connected between the first output point P1 and the semiconductor switching elements U1, V1, and W1. The switch S4 is commonly connected between the second output point P2 and the semiconductor switching elements U4, V4, and W4. The switch S5 is commonly connected between the third output point P3 and the connection point between diodes D5 and D6, the connection point between diodes D7 and D8, and the connection point between diodes D9 and D10. The switches S3, S4, and S5 may be controllable switches such as semiconductor switches or electromagnetic relays. The third protection device 37 allows the output of DC output power from the converter circuit 311 to the inverter circuit 312 when the switches S3, S4, and S5 are closed in the on state, and stops the output of DC output power from the converter circuit 311 to the inverter circuit 312 when the switches S3, S4, and S5 are open in the off state.

[0204] When stopping the output of power to the compressor 4, the safety level increases in the order of stopping the input of input power, stopping the output of DC output power, and stopping the output of AC output power. Therefore, after the operation of the first protection device 33, the third protection device 37 may be operated before the operation of the second protection device 34. Note that if the third protection device 37 is present, the second protection device 34 may be omitted.

[0205] In one variant, the third protection device 37 is not limited to a circuit configuration including switches S3, S4, and S5, but may include a circuit configuration that adjusts the magnitude of the DC output power, for example, the magnitude of the voltage, output from the converter circuit 311 to the inverter circuit 312.

[0206] In one modified example, the state detection circuit 32 is not limited to a configuration that detects the voltage value of the DC output power of the converter circuit 311. The state detection circuit 32 may be configured to detect the state of at least one of the compressor 4 and the drive circuit 31.

[0207] For example, the state of the drive circuit 31 may be the current value of the current flowing through the connection lines corresponding to the three phases of the AC output power output from the inverter circuit 312 to the compressor 4. In other words, the state detection circuit 32 may detect the AC output power. In this case, the unsteady state of the drive circuit 31 may include an unsteady state related to a leakage current detected between the connection lines corresponding to the three phases of the AC output power. Since the method of detecting an unsteady state related to a leakage current is well known, a detailed description thereof will be omitted. In another example, the state of the drive circuit 31 may be the current value of the current flowing through the drive circuit 31. As an example, the current value of the current flowing through the drive circuit 31 may include at least one of the current values ​​of the output AC current of the U-phase, V-phase, and W-phase legs of the drive circuit 31. In this case, the unsteady state of the drive circuit 31 is a current abnormality. The control circuit 35 may detect a current abnormality in response to the current value of the current flowing through the drive circuit 31 detected by the state detection circuit 32 exceeding a predetermined current value. As another example, the current value of the current flowing in the drive circuit 31 may include the current value of the direct current flowing between the converter circuit 311 and the inverter circuit 312 of the drive circuit 31. In this case, the control circuit 35 may determine that a current abnormality has occurred in the drive circuit 31 if the current value of the direct current flowing between the converter circuit 311 and the inverter circuit 312 of the drive circuit 31 exceeds a predetermined current value.

[0208] For example, the state of the compressor 4 may include at least one of the phase current of the compressor 4 and the rotation speed of the motor 42 of the compressor 4. The current value of the phase current of the compressor 4 may include the current values ​​of the U phase, the V phase, and the W phase. In this case, the unsteady state of the compressor 4 may include an abnormality related to a layer short of the compressor 4. An abnormality related to a layer short of the compressor 4 may include the layer short of the compressor 4 itself, an abnormality that may cause the layer short of the compressor 4, and an abnormality that may be caused by the layer short of the compressor 4. Specific examples of abnormalities related to a layer short of the compressor 4 include a layer short of the compressor 4, a ground fault of the compressor 4, and open-phase operation of the compressor 4. If an imbalance in the phase currents of the compressor 4 occurs, an abnormality related to a layer short of the compressor 4 may have occurred. The control circuit 35 may determine whether an unsteady state of the compressor 4 has occurred based on the state of the compressor 4 detected by the state detection circuit 32. For example, if an imbalance in the phase currents of the compressor 4 occurs, the control circuit 35 may determine that an abnormality related to a layer short in the compressor 4 has occurred. Furthermore, if a deviation in the rotation speed of the motor 42 of the compressor 4 occurs, there is a possibility that an abnormality related to a layer short in the compressor 4 has occurred.

[0209] In one variant, the power supply 10 may be any of a variety of AC power sources, particularly a commercial power source. The voltage and frequency of the commercial power source vary depending on the country, and the drive circuit 31 may be configured to be able to drive the motor 42 using any of a variety of commercial power sources.

[0210] In one modified example, the drive circuit 31 may be configured to supply AC output power corresponding to the type of the electric motor 42. The AC output power is not limited to three-phase AC power, but may be single-phase AC power.

[0211] In one variation, the converter circuit 311 may have a plurality of third output points. The plurality of third output points may output different voltages. The inverter circuit 312 may have a plurality of third semiconductor switching element groups connected between the plurality of third output points and the electric motor 42. If the total number of the first output point P1, the second output point P2, and the plurality of third output points P3 is n, the drive circuit 31 can provide voltages at (2×n−1) levels. By increasing n, the voltage waveform applied to the electric motor 42 by the drive circuit 31 can be made closer to a sine wave.

[0212] In one modified example, the circuit configuration of the inverter circuit 312 is not limited to the circuit configuration shown in FIG. 3 . The circuit configuration of the inverter circuit 312 shown in FIG. 3 is a so-called NPC (Neutral-Point-Clamped) type, but may also be an A-NPC (Advanced-NPC) type. The inverter circuit 312 only needs to have multiple semiconductor switching element groups connected between multiple output points with different voltages and the electric motor. The multiple semiconductor switching elements constituting the multiple semiconductor switching element groups may include semiconductor switching elements that are common to two or more semiconductor switching element groups. The inverter circuit 312 does not necessarily have to be a multilevel inverter.

[0213] In one variant, the unsteady state notifications, such as the first to third unsteady state notifications, may be issued directly or indirectly. Direct issuance refers to outputting the unsteady state notification directly from the air conditioner using the outdoor unit 1a, indoor unit 1b, remote controller, or the like. For example, the unsteady state notification may be output using light from a light source device (such as an LED, red light, or warning indicator lamp) provided in the outdoor unit 1a, indoor unit 1b, or remote controller of the air conditioner, sound from a sound generating device (such as a speaker, buzzer, alarm, sound generator, or alarm), or visual display (such as a message display or a flashing backlight) from a display device (such as a display or display panel). Indirect issuance refers to outputting and / or storing the unsteady state notification outside the air conditioner via a communication network such as the Internet or a server. Indirect notifications include push notifications (notifications to mobile phones and smartphones), notifications to voice assistants (Alexa echo, Google home, etc.), automatic notifications to manufacturers or maintenance companies, sending messages to monitoring equipment of management companies, notifications to service centers, etc., notifications to fire engines or security companies, and saving in the history of non-steady states in storage devices.

[0214] In one modified example, the refrigeration cycle device 1 is not limited to an air conditioner, but may be a freezing or refrigeration device such as a refrigerator or a freezer.

[0215] [3. Aspects] As is clear from the above-described embodiment and modifications, the present disclosure includes the following aspects.

[0216] [Aspect 1] A method for operating a refrigeration cycle circuit including a compressor, a condenser, an expansion valve, and an evaporator, and through which a working medium circulates, wherein the working medium contains a refrigerant component capable of producing hydrogen fluoride, the operating method comprising: producing the hydrogen fluoride from the working medium in the refrigeration cycle circuit; reacting the hydrogen fluoride with a compound represented by formula (1) or formula (2); and circulating the working medium, R in formula (1) １ ~R ４ At least one of R is selected from a hydroxy group, an alkoxy group, or an acyl group; １~R ４ The remainder of R is selected from an alkyl group, a vinyl group, an aryl group, a substituent derived from any of these, and a halogeno group; ５ , R ６ is selected from a hydroxy group, an alkoxy group, an acyl group, an alkyl group, a vinyl group, an aryl group, and substituents derived therefrom, and a halogeno group.

[0217] [Aspect 2] The operating method of Aspect 1, wherein an adsorption tube is disposed in the refrigeration cycle circuit, the adsorption tube contains the compound as an adsorbent, and the operating method includes switching a path between the compressor and the condenser or the evaporator from a first path that does not pass through the adsorption tube to a second path that passes through the adsorption tube.

[0218] [Aspect 3] The operating method according to Aspect 1 or 2, wherein the operating method includes switching from the first path to the second path in response to detection of an unsteady state of at least one of the compressor and a drive circuit that drives the compressor.

[0219] [Aspect 4] The operating method of Aspect 1, wherein the compound represented by formula (2) is silicone oil, and the silicone oil is dissolved in refrigeration oil for the compressor.

[0220] [Aspect 5] The silicone oil has a kinematic viscosity of 20 to 100 mm at 40°C. ２ / s and has compatibility with polyvinyl ether or polyol ester based synthetic oil.

[0221] [Aspect 6] A compound represented by formula (1) or formula (2), R in formula (1) １ ~R ４ At least one of R is selected from a hydroxy group, an alkoxy group, or an acyl group; １ ~R ４ The remainder of R is selected from an alkyl group, a vinyl group, an aryl group, a substituent derived from any of these, and a halogeno group; ５ , R ６is selected from a hydroxy group, an alkoxy group, an acyl group, an alkyl group, a vinyl group, an aryl group, and substituents derived from these groups, and a halogeno group.

[0222] [Aspect 7] A refrigeration cycle device comprising: a refrigeration cycle circuit; and the refrigeration cycle composition of Aspect 6 present in the refrigeration cycle circuit.

[0223] [Aspect 8] The refrigeration cycle device of Aspect 7, further comprising a hydrogen fluoride capture mechanism, wherein the refrigeration cycle circuit includes a compressor, a condenser, an expansion valve, and an evaporator, and a working medium circulates therethrough, the working medium including a refrigerant component capable of generating hydrogen fluoride, and the hydrogen fluoride capture mechanism includes the refrigeration cycle composition and captures hydrogen fluoride within the refrigeration cycle circuit.

[0224] [Aspect 9] The refrigeration cycle device of Aspect 8, wherein the refrigeration cycle circuit includes a first heat exchanger that functions as the evaporator or the condenser, and a plurality of second heat exchangers that function as the condensers when the first heat exchanger functions as the evaporator, and the plurality of second heat exchangers are connected in parallel to the first heat exchanger.

[0225] [Aspect 10] The refrigeration cycle device according to Aspect 8 or 9, wherein the hydrogen fluoride capture mechanism includes an adsorption tube disposed in the refrigeration cycle circuit, and the adsorption tube contains the refrigeration cycle composition as an adsorbent.

[0226] [Aspect 11] The refrigeration cycle apparatus of Aspect 10, wherein the hydrogen fluoride capture mechanism includes a switching device, and the switching device is capable of switching a path between the compressor and the condenser or the evaporator between a first path that does not pass through the adsorption tube and a second path that passes through the adsorption tube.

[0227] Aspect 12: The refrigeration cycle apparatus of Aspect 11, further comprising: a control device that controls the refrigeration cycle circuit and the hydrogen fluoride capturing mechanism, wherein the control device comprises: a drive circuit that drives the compressor; a state detection circuit that detects a state of at least one of the compressor and the drive circuit; and a control circuit that controls the drive circuit and the switching device, wherein the control circuit switches from the first path to the second path using the switching device in response to detection of an unsteady state of at least one of the compressor and the drive circuit.

[0228] [Aspect 13] The refrigeration cycle device according to Aspect 8 or 9, wherein the compound is silicone oil, and the silicone oil is dissolved in refrigerating machine oil for the compressor.

[0229] [Aspect 14] The refrigeration cycle device according to Aspect 12, wherein the control circuit stops or limits operation of the refrigeration cycle circuit in response to detection of an unsteady state of at least one of the compressor and the drive circuit.

[0230] [Aspect 15] The refrigeration cycle apparatus of Aspect 14, wherein the drive circuit includes an inverter circuit that outputs AC output power to the compressor, the state detection circuit detects the AC output power, and the unsteady state includes an abnormality related to leakage current detected between connection lines corresponding to three phases of the AC output power.

[0231] [Aspect 16] The refrigeration cycle apparatus of Aspect 14, wherein the drive circuit includes: a converter circuit that outputs DC output power based on input power from a power source so that the voltage becomes a first voltage; and an inverter circuit that outputs AC output power to the compressor based on the DC output power; the state detection circuit detects the DC output power and outputs a detection voltage indicating the voltage of the DC output power; and the unsteady state includes a state in which the detection voltage is less than a second voltage that is equal to or less than the first voltage.

[0232] [Aspect 17] The refrigeration cycle apparatus of Aspect 16, wherein the second voltage is 0.3 to 0.8 times the first voltage.

[0233] [Aspect 18] The refrigeration cycle device of any one of Aspects 8 to 17, wherein the refrigerant component capable of producing hydrogen fluoride includes an ethylene-based fluoroolefin that undergoes a disproportionation reaction. [Aspect 19] The refrigeration cycle device of Aspect 18, wherein the working fluid includes a C1 or C2 haloalkane as a disproportionation inhibitor that suppresses the disproportionation reaction of the ethylene-based fluoroolefin.

[0234] [Aspect 20] The refrigeration cycle apparatus according to Aspect 18 or 19, wherein the refrigerant component capable of producing hydrogen fluoride is 1,1,2-trifluoroethylene, trans-1,2-difluoroethylene, cis-1,2-difluoroethylene, 1,1-difluoroethylene, tetrafluoroethylene, or monofluoroethylene.

[0235] [Aspect 21] The refrigeration cycle device according to any one of Aspects 18 to 20, wherein the working fluid further contains difluoromethane as the refrigerant component.

[0236] [Aspect 22] The refrigeration cycle device according to any one of Aspects 18 to 21, wherein the working medium further contains a saturated hydrocarbon.

[0237] [Aspect 23] The refrigeration cycle device of Aspect 22, wherein the saturated hydrocarbon includes n-propane.

[0238] [Aspect 24] A control method executed by a control device that controls a refrigeration cycle circuit including a compressor, a condenser, an expansion valve, and an evaporator, through which a working medium circulates, and a hydrogen fluoride capture mechanism, wherein the working medium includes a refrigerant component capable of generating hydrogen fluoride, the hydrogen fluoride capture mechanism includes an adsorption tube disposed in the refrigeration cycle circuit and a switching device, the adsorption tube includes a compound represented by formula (1) or formula (2) as an adsorbent, R in formula (1) １ ~R ４ At least one of R is selected from a hydroxy group, an alkoxy group, or an acyl group; １ ~R ４The remainder of R is selected from an alkyl group, a vinyl group, an aryl group, a substituent derived from any of these, and a halogeno group; ５ , R ６ is selected from a hydroxy group, an alkoxy group, an acyl group, an alkyl group, a vinyl group, an aryl group, and substituents derived therefrom, and a halogeno group; the switching device is capable of switching a path between the compressor and the condenser or the evaporator between a first path that does not pass through the adsorption tube and a second path that passes through the adsorption tube; the control device comprises: a drive circuit that drives the compressor; and a control circuit that controls the drive circuit and the switching device; and the control method switches the first path to the second path by the switching device in response to detection of an unsteady state of at least one of the compressor and the drive circuit.

[0239] [Aspect 25] A program executed by a computer system provided in a control device that controls a refrigeration cycle circuit including a compressor, a condenser, an expansion valve, and an evaporator, through which a working medium circulates, and a hydrogen fluoride capture mechanism, wherein the working medium is a refrigerant component capable of generating hydrogen fluoride, the hydrogen fluoride capture mechanism includes an adsorption tube and a switching device that are disposed in the refrigeration cycle circuit, and the adsorption tube includes a compound represented by formula (1) or formula (2) as an adsorbent, R in formula (1) １ ~R ４ At least one of R is selected from a hydroxy group, an alkoxy group, or an acyl group; １ ~R ４ The remainder of R is selected from an alkyl group, a vinyl group, an aryl group, a substituent derived from any of these, and a halogeno group; ５ , R ６is selected from a hydroxy group, an alkoxy group, an acyl group, an alkyl group, a vinyl group, an aryl group, and substituents derived therefrom, and a halogeno group; the switching device is capable of switching a path between the compressor and the condenser or the evaporator between a first path that does not pass through the adsorption tube and a second path that passes through the adsorption tube; the control device comprises: a drive circuit that drives the compressor; and a control circuit that controls the drive circuit and the switching device; and the program causes the computer system to switch from the first path to the second path by the switching device in response to detection of an unsteady state of at least one of the compressor and the drive circuit.

[0240] Aspects 2 to 5 and 8 to 23 are optional elements and are not essential.

[0241] The present disclosure is applicable to a method for operating a refrigeration cycle circuit, a refrigeration cycle composition, a refrigeration cycle device, a control method, and a program. Specifically, the present disclosure is applicable to a method for operating a refrigeration cycle circuit in which a working fluid contains an ethylene-based fluoroolefin as a refrigerant component, a refrigeration cycle composition used in the refrigeration cycle circuit, a refrigeration cycle device including the refrigeration cycle circuit, a control method executed by a control device of the refrigeration cycle device, and a program (computer program) used in the control device.

[0242] REFRIGERATION CYCLE DEVICE 1, 1A, 1B REFRIGERATION CYCLE DEVICE 2, 2A, 2B REFRIGERATION CYCLE CIRCUIT 3, 3A, 3B, 3G CONTROL DEVICE 4 COMPRESSOR 5 FIRST HEAT EXCHANGER (CONDENSER, EVAPORATIVE) 6 EXPANSION VALVE 7 SECOND HEAT EXCHANGER (CONDENSER, EVAPORATIVE) 10 POWER SUPPLY 11, 11A, 11B HYDROGEN FLUORIDE CAPTURE MECHANISM 12, 12C, 12D, 12E, 12F ABSORBING TUBE 13, 13A SWITCHING DEVICE 13a, 13b THREE-WAY VALVE 13c FOUR-WAY VALVE 13d THREE-WAY VALVE R11 FIRST PATH R12 SECOND PATH 20 WORKING MEDIUM 31 DRIVE CIRCUIT 32 STATUS DETECTION CIRCUIT 35, 35A, 35B control circuit

Claims

1. A method for operating a refrigeration cycle circuit including a compressor, a condenser, an expansion valve, and an evaporator, and through which a working medium circulates, wherein the working medium includes a refrigerant component capable of generating hydrogen fluoride, the operating method includes: generating the hydrogen fluoride from the working medium in the refrigeration cycle circuit; reacting the hydrogen fluoride with a compound represented by formula (1) or formula (2); and circulating the working medium, R in formula (1) １ ~R ４ At least one of R is selected from a hydroxy group, an alkoxy group, or an acyl group; １ ~R ４ The remainder of R is selected from an alkyl group, a vinyl group, an aryl group, a substituent derived therefrom, and a halogeno group; ５ , R ６ is selected from a hydroxy group, an alkoxy group, an acyl group, an alkyl group, a vinyl group, an aryl group and substituents derived therefrom, and a halogeno group.

2. The operating method according to claim 1, wherein an adsorption tube is disposed within the refrigeration cycle circuit, the adsorption tube contains the compound as an adsorbent, and the operating method includes switching a path between the compressor and the condenser or the evaporator from a first path that does not pass through the adsorption tube to a second path that passes through the adsorption tube.

3. The operating method according to claim 2, further comprising switching from the first path to the second path in response to detection of an unsteady state of at least one of the compressor and a drive circuit that drives the compressor.

4. The operating method according to claim 1, wherein the compound represented by formula (2) is silicone oil, and the silicone oil is dissolved in refrigeration oil for the compressor.

5. The silicone oil has a kinetic viscosity of 20 to 100 mm at 40°C. ２ 5. The method of claim 4, wherein the composition is a polyvinyl ether or polyol ester synthetic oil.

6. A compound represented by formula (1) or formula (2), R in formula (1) １ ~R ４ At least one of R is selected from a hydroxy group, an alkoxy group, or an acyl group; １ ~R ４ The remainder of R is selected from an alkyl group, a vinyl group, an aryl group, a substituent derived therefrom, and a halogeno group; ５ , R ６ is selected from a hydroxy group, an alkoxy group, an acyl group, an alkyl group, a vinyl group, an aryl group, or a substituent derived therefrom, and a halogeno group.

7. A refrigeration cycle device comprising: a refrigeration cycle circuit; and the composition for a refrigeration cycle according to claim 6 present in the refrigeration cycle circuit.

8. The refrigeration cycle device of claim 7, further comprising a hydrogen fluoride capture mechanism, wherein the refrigeration cycle circuit includes a compressor, a condenser, an expansion valve, and an evaporator, and a working medium circulates, the working medium containing a refrigerant component capable of generating hydrogen fluoride, and the hydrogen fluoride capture mechanism contains the refrigeration cycle composition and captures the hydrogen fluoride within the refrigeration cycle circuit.

9. The refrigeration cycle device of claim 8, wherein the refrigeration cycle circuit comprises a first heat exchanger functioning as the evaporator or the condenser, and a plurality of second heat exchangers functioning as the condensers when the first heat exchanger functions as the evaporator, and the plurality of second heat exchangers are connected in parallel to the first heat exchanger.

10. The refrigeration cycle device according to claim 8, wherein the hydrogen fluoride capture mechanism includes an adsorption tube disposed in the refrigeration cycle circuit, and the adsorption tube contains the refrigeration cycle composition as an adsorbent.

11. The refrigeration cycle apparatus of claim 10, wherein the hydrogen fluoride capture mechanism includes a switching device that is capable of switching a path between the compressor and the condenser or the evaporator between a first path that does not pass through the adsorption tube and a second path that passes through the adsorption tube.

12. The refrigeration cycle device according to claim 8, wherein the refrigerant component capable of generating hydrogen fluoride includes an ethylene-based fluoroolefin that undergoes a disproportionation reaction.

13. The refrigeration cycle device according to claim 12, wherein the working fluid contains a haloalkane having 1 or 2 carbon atoms as a disproportionation inhibitor for suppressing the disproportionation reaction of the ethylene-based fluoroolefin.

14. A control method executed by a control device that controls a refrigeration cycle circuit including a compressor, a condenser, an expansion valve, and an evaporator, in which a working medium circulates, and a hydrogen fluoride capture mechanism, wherein the working medium includes a refrigerant component capable of generating hydrogen fluoride, the hydrogen fluoride capture mechanism includes an adsorption tube disposed in the refrigeration cycle circuit, and a switching device, the adsorption tube includes a compound represented by formula (1) or formula (2) as an adsorbent, R in formula (1) １ ~R ４ At least one of R is selected from a hydroxy group, an alkoxy group, or an acyl group; １ ~R ４ The remainder of R is selected from an alkyl group, a vinyl group, an aryl group, a substituent derived therefrom, and a halogeno group; ５ , R ６ is selected from a hydroxy group, an alkoxy group, an acyl group, an alkyl group, a vinyl group, an aryl group, and substituents derived therefrom, and a halogeno group; the switching device is capable of switching a path between the compressor and the condenser or the evaporator between a first path that does not pass through the adsorption tube and a second path that passes through the adsorption tube; the control device comprises: a drive circuit that drives the compressor; and a control circuit that controls the drive circuit and the switching device; and the control method comprises switching the first path to the second path by the switching device in response to detection of an unsteady state of at least one of the compressor and the drive circuit.

15. A program executed by a computer system equipped with a control device that controls a refrigeration cycle circuit including a compressor, a condenser, an expansion valve, and an evaporator, in which a working medium circulates, and a hydrogen fluoride capture mechanism, wherein the working medium includes a refrigerant component capable of generating hydrogen fluoride, the hydrogen fluoride capture mechanism includes an adsorption tube disposed in the refrigeration cycle circuit, and a switching device, the adsorption tube includes a compound represented by formula (1) or formula (2) as an adsorbent, R in formula (1) １ ~R ４ At least one of R is selected from a hydroxy group, an alkoxy group, or an acyl group; １ ~R ４ The remainder of R is selected from an alkyl group, a vinyl group, an aryl group, a substituent derived therefrom, and a halogeno group; ５ , R ６ is selected from a hydroxy group, an alkoxy group, an acyl group, an alkyl group, a vinyl group, an aryl group, and substituents derived therefrom, and a halogeno group; the switching device is capable of switching a path between the compressor and the condenser or the evaporator between a first path that does not pass through the adsorption tube and a second path that passes through the adsorption tube; the control device comprises: a drive circuit that drives the compressor; and a control circuit that controls the drive circuit and the switching device; and the program causes the computer system to switch from the first path to the second path by the switching device in response to detection of an unsteady state of at least one of the compressor and the drive circuit.

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