JP2014061787A - Cooling device of electric apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a cooling device of an electric apparatus which stably cools the electric apparatus.SOLUTION: A cooling device of an electric apparatus comprises a cooling part 30 for cooling an inverter element 110. The cooling part 30 comprises: a thermal mass 130 which transmits heat generated by the inverter element 110; an air cooling fin 140 which radiates the heat transmitted through the thermal mass 130; and an air conditioner refrigerant pipeline 120 which forms a refrigerant passage 32 in which a refrigerant for vehicle compartment air conditioner circulates. A thermal mass internal tank 150 in which a coolant is disposed is formed in the thermal mass 130. The cooling part 30 further includes: a tank 156 which is provided so as to connect with the thermal mass internal tank 150 and may store the coolant; and a piston pump 170 which utilizes a pressure of the refrigerant for the vehicle compartment air conditioner to discharge the coolant from the thermal mass internal tank 150 to the tank 156.

Description

  TECHNICAL FIELD The present invention generally relates to a cooling device for an electrical device, and more specifically, to a cooling device for an electrical device that uses both cooling using a refrigerant for air conditioning in a passenger compartment and cooling using a fin structure. is there.

  With respect to a conventional cooling device for electric equipment, for example, Japanese Patent Application Laid-Open No. 2007-69733 discloses a vehicle air conditioner for efficiently cooling a heating element such as a battery and improving heating performance. A heating element cooling system using the above has been disclosed (Patent Document 1). In the heating element cooling system disclosed in Patent Document 1, a heat exchanger that exchanges heat with air-conditioning air and a heat exchanger that exchanges heat with the heating element are arranged in parallel in a refrigerant passage from an expansion valve to a compressor. And the heating element is cooled using the refrigerant for the air conditioner.

  In addition, JP 2005-90862 A (Patent Document 2), JP 2008-109131 A (Patent Document 3), JP 2002-270748 A (Patent Document 4), and JP 60-204986 A. (Patent Document 5) also discloses a cooling device for various electric devices.

JP 2007-69733 A JP-A-2005-90862 JP 2008-109131 A JP 2002-270748 A JP-A-60-204986

  As disclosed in the above-mentioned patent document, a technique using a vapor compression refrigeration cycle for air conditioning in a passenger compartment has been proposed as a cooling device for cooling an electric device mounted on a vehicle. However, in such a cooling device, the refrigerant for the air conditioning of the passenger compartment does not circulate sufficiently when the refrigeration cycle system is not stable, such as when the vehicle is started, and the cooling efficiency of the electrical equipment can be temporarily reduced. There is sex.

  Accordingly, an object of the present invention is to solve the above-described problem and to provide a cooling device for an electric device that stably cools the electric device.

  The cooling device for electric equipment according to the present invention is a cooling device for electric equipment mounted on a vehicle. The cooling device for an electric device includes a cooling unit for cooling a heat source included in the electric device. The cooling unit has a first surface on which the heat generation source is provided and a second surface disposed on the back side of the first surface, and is provided on the second surface with a heat transfer member that transmits heat generated by the heat generation source. The fin part which radiates the heat transmitted through the heat transfer member, and the refrigerant passage forming member which is provided on the first surface and forms a refrigerant passage through which the refrigerant for air conditioning of the passenger compartment flows. The heat transfer member is provided with a heat transfer medium space provided between the first surface and the second surface and in which a heat transfer medium different from the refrigerant flowing through the refrigerant passage is disposed. The cooling unit is connected to the heat transfer medium space and discharges the heat transfer medium from the heat transfer medium space to the tank using the tank capable of storing the heat transfer medium and the pressure of the refrigerant for air conditioning in the passenger compartment. And a discharge mechanism section.

  According to the cooling device for an electrical device configured as described above, the cooling unit is provided with the discharge mechanism unit that discharges the heat transfer medium from the heat transfer medium space to the tank using the pressure of the refrigerant for the vehicle compartment air conditioning. Thus, a cooling mode in which heat is radiated from the heat source while the heat transfer medium is disposed in the heat transfer medium space and a cooling mode in which the heat is radiated from the heat source while the heat transfer medium is discharged from the heat transfer medium space are selectively adopted. be able to. Thereby, an electric equipment can be cooled stably.

  Preferably, the discharge mechanism section includes a piston pump that is provided in connection with the heat transfer medium space and on which the pressure of the refrigerant for vehicle air is applied. The piston pump operates so as to push out the heat transfer medium from the heat transfer medium space when the pressure of the refrigerant for air conditioning in the passenger compartment exceeds a predetermined value.

  According to the cooling device for an electrical device configured in this way, when the refrigerant pressure for the passenger compartment air conditioning is low, the circulation of the refrigerant for the passenger compartment air conditioning in the refrigerant passage is not sufficient. A cooling mode is adopted in which heat is dissipated from the heat source in a state where the is disposed. On the other hand, when the refrigerant pressure for vehicle compartment air conditioning is high, the refrigerant passage for vehicle compartment air conditioning in the refrigerant passage is sufficiently distributed, so that the heat transfer medium radiates heat from the heat generation medium while the heat transfer medium is discharged from the heat transfer medium space. Take. As a result, the electric device can be cooled in an optimum cooling mode corresponding to the cooling capacity of the refrigerant for air conditioning in the passenger compartment.

  Preferably, the cooling unit further includes a valve mechanism that temporarily reduces the pressure of the refrigerant for air conditioning in the passenger compartment transmitted to the discharge mechanism unit.

  According to the cooling device for electric equipment configured as described above, the flow of the refrigerant for vehicle compartment air conditioning in the refrigerant passage is sufficient, but when it is desired to temporarily increase the cooling capacity of the electric equipment, the heat transfer medium space It is possible to adopt a cooling mode in which heat is radiated from the heat source in a state where the heat transfer medium is disposed on the surface.

  Preferably, the electrical device cooling apparatus includes a temperature measuring unit for measuring the temperature of the heat transfer member, and a control unit for controlling the operation of the valve mechanism based on the temperature T1 measured by the temperature measuring unit. Further prepare. When the value of T1 is equal to or greater than θ1 (θ1 is a preset threshold value), the control unit operates the valve mechanism so as to reduce the pressure of the refrigerant for vehicle compartment air conditioning transmitted to the discharge mechanism unit. Let

  According to the cooling device for an electric device configured as described above, it is possible to detect a lack of cooling capacity of the electric device based on the temperature of the heat transfer member measured by the temperature measuring unit.

  Preferably, the tank has a heat radiating section that radiates heat from the heat transfer medium stored in the tank to the periphery of the tank.

  According to the cooling device for an electrical device configured as described above, when the heat transfer medium whose temperature has increased in the heat transfer medium space is transferred to the tank, the heat transfer medium can dissipate heat from the heat transfer medium to the periphery of the tank. it can.

  As described above, according to the present invention, it is possible to provide a cooling device for an electric device that stably cools the electric device.

1 is a schematic diagram showing a vehicle to which a cooling device for an electrical device in an embodiment of the present invention is applied. It is a figure which shows typically the structure of the cooling device of the electric equipment in embodiment of this invention. It is a Mollier diagram which shows the state of the refrigerant | coolant in the vapor compression refrigeration cycle in FIG. It is a schematic diagram which shows the flow of the refrigerant | coolant which cools EV apparatus during the driving | operation of a vapor compression refrigeration cycle. It is a schematic diagram which shows the flow of the refrigerant | coolant which cools EV apparatus during the stop of a vapor compression refrigeration cycle. It is a figure which shows the opening-and-closing state of a flow regulating valve and a switching valve in the cooling device of the electric equipment in embodiment of this invention. It is a structure of the cooling unit in FIG. 2, Comprising: It is sectional drawing which shows heat mass cooling mode. It is a structure of the cooling part in FIG. 2, Comprising: It is sectional drawing which shows an air-conditioner refrigerant | coolant cooling mode. It is sectional drawing which shows the 1st modification of the cooling device of the electric equipment in embodiment of this invention. It is sectional drawing which shows the 2nd modification of the cooling device of the electric equipment in embodiment of this invention. It is another sectional view showing the 2nd modification of the cooling device of the electric equipment in an embodiment of this invention. It is a block diagram which shows the control system in the modification in FIG. 10 and FIG. It is sectional drawing which shows the structure of the cooling part for a comparison.

  Embodiments of the present invention will be described with reference to the drawings. In the drawings referred to below, the same or corresponding members are denoted by the same reference numerals.

  FIG. 1 is a schematic diagram showing a vehicle to which a cooling device for electrical equipment according to an embodiment of the present invention is applied.

  A vehicle 1000 includes an engine 100 that is an internal combustion engine, a drive unit 200 that is an electric motor, a PCU (Power Control Unit) 700, and a traveling battery 400. The hybrid uses the engine 100 and the drive unit 200 as power sources. It is a car.

  Engine 100 may be a gasoline engine or a diesel engine. Drive unit 200 generates a driving force for driving vehicle 1000 together with engine 100. Engine 100 and drive unit 200 are both provided in the engine room of vehicle 1000. The drive unit 200 is electrically connected to the PCU 700 by a cable 500. PCU 700 is electrically connected to traveling battery 400 by cable 600.

  FIG. 2 is a diagram schematically showing a configuration of a cooling device for an electric device in the embodiment of the present invention.

  Referring to FIG. 2, the cooling device for electric equipment in the present embodiment includes a vapor compression refrigeration cycle 10. The vapor compression refrigeration cycle 10 is mounted on the vehicle 1000, for example, for cooling the passenger compartment. For cooling using the vapor compression refrigeration cycle 10, for example, when a switch for performing cooling is turned on, or an automatic control mode for automatically adjusting the temperature in the passenger compartment to a set temperature is selected. And when the temperature in the passenger compartment is higher than the set temperature.

  The vapor compression refrigeration cycle 10 includes a compressor 12, a heat exchanger 14 as a first heat exchanger, a heat exchanger 15, an expansion valve 16 as an example of a decompressor, and a second heat exchanger. And a heat exchanger 18. The vapor compression refrigeration cycle 10 includes a gas-liquid separator 40 disposed on a refrigerant path between the heat exchanger 14 and the heat exchanger 15.

  The compressor 12 operates using a motor or engine mounted on the vehicle as a power source, and compresses the refrigerant gas in an adiabatic manner to form an overheated refrigerant gas. The compressor 12 sucks and compresses the refrigerant flowing from the heat exchanger 18 when the vapor compression refrigeration cycle 10 is operated, and discharges a high-temperature and high-pressure gas-phase refrigerant into the refrigerant passage 21. The compressor 12 circulates the refrigerant in the vapor compression refrigeration cycle 10 by discharging the refrigerant into the refrigerant passage 21.

  The heat exchangers 14 and 15 dissipate the superheated refrigerant gas compressed in the compressor 12 isothermally to an external medium to obtain a refrigerant liquid. The high-pressure gas-phase refrigerant discharged from the compressor 12 is condensed (liquefied) by releasing heat to the surroundings in the heat exchangers 14 and 15 and being cooled. The heat exchangers 14 and 15 have tubes that circulate the refrigerant, and fins for exchanging heat between the refrigerant that circulates in the tubes and the air around the heat exchangers 14 and 15.

  The heat exchangers 14 and 15 exchange heat between the cooling air and the refrigerant. The cooling air may be supplied to the heat exchangers 14 and 15 by natural ventilation generated by traveling of the vehicle. The cooling air may be supplied to the heat exchangers 14 and 15 by forced ventilation from a cooling fan such as the condenser fan 42 or a radiator fan for cooling the engine. By the heat exchange in the heat exchangers 14 and 15, the temperature of the refrigerant is lowered and the refrigerant is liquefied.

  The expansion valve 16 expands by injecting a high-pressure liquid-phase refrigerant flowing through the refrigerant passage 25 from a small hole, and changes it into a low-temperature / low-pressure mist refrigerant. The expansion valve 16 depressurizes the refrigerant liquid condensed by the heat exchangers 14 and 15 to obtain wet steam in a gas-liquid mixed state. Note that the decompressor for decompressing the refrigerant liquid is not limited to the expansion valve 16 that is squeezed and expanded, and may be a capillary tube.

  The heat exchanger 18 absorbs heat of ambient air introduced so as to come into contact with the heat exchanger 18 by vaporizing the mist refrigerant flowing through the heat exchanger 18. The heat exchanger 18 uses the refrigerant decompressed by the expansion valve 16 to absorb the heat of vaporization when the refrigerant's wet vapor evaporates into the refrigerant gas from the air-conditioning air flowing into the vehicle interior. Cool the room. The air-conditioning air whose temperature has been lowered by the heat being absorbed by the heat exchanger 18 is returned to the passenger compartment, thereby cooling the passenger compartment. The refrigerant absorbs heat from the surroundings in the heat exchanger 18 and is heated.

  The heat exchanger 18 has a tube that circulates the refrigerant, and fins that exchange heat between the refrigerant that circulates in the tube and the air around the heat exchanger 18. A wet steam refrigerant circulates in the tube. When the refrigerant circulates in the tube, the refrigerant evaporates by absorbing the heat of the air in the vehicle interior as latent heat of evaporation via the fins, and further becomes superheated steam by sensible heat. The vaporized refrigerant flows to the compressor 12 via the refrigerant passage 27. The compressor 12 compresses the refrigerant flowing from the heat exchanger 18.

  The vapor compression refrigeration cycle 10 includes a refrigerant passage 21 that communicates the compressor 12 and the heat exchanger 14, refrigerant passages 22, 23, and 24 that communicate the heat exchanger 14 and the heat exchanger 15, and a heat exchanger. 15 and a refrigerant passage 25 that communicates the expansion valve 16, a refrigerant passage 26 that communicates the expansion valve 16 and the heat exchanger 18, and a refrigerant passage 27 that communicates the heat exchanger 18 and the compressor 12.

  The refrigerant passage 21 is a passage for circulating the refrigerant from the compressor 12 to the heat exchanger 14. The refrigerant flows between the compressor 12 and the heat exchanger 14 from the outlet of the compressor 12 toward the inlet of the heat exchanger 14 via the refrigerant passage 21. The refrigerant passages 22 to 25 are passages for circulating the refrigerant from the heat exchanger 14 to the expansion valve 16. The refrigerant flows between the heat exchanger 14 and the expansion valve 16 from the outlet of the heat exchanger 14 toward the inlet of the expansion valve 16 via the refrigerant passages 22 to 25.

  The refrigerant passage 26 is a passage for circulating the refrigerant from the expansion valve 16 to the heat exchanger 18. The refrigerant flows between the expansion valve 16 and the heat exchanger 18 from the outlet of the expansion valve 16 toward the inlet of the heat exchanger 18 via the refrigerant passage 26. The refrigerant passage 27 is a passage for circulating the refrigerant from the heat exchanger 18 to the compressor 12. The refrigerant flows between the heat exchanger 18 and the compressor 12 from the outlet of the heat exchanger 18 toward the inlet of the compressor 12 via the refrigerant passage 27.

  The vapor compression refrigeration cycle 10 is configured by connecting a compressor 12, heat exchangers 14 and 15, an expansion valve 16, and a heat exchanger 18 through refrigerant passages 21 to 27. As the refrigerant of the vapor compression refrigeration cycle 10, for example, carbon dioxide, hydrocarbons such as propane and isobutane, ammonia, chlorofluorocarbons or water can be used.

  The gas-liquid separator 40 is provided on the refrigerant path between the heat exchanger 14 and the heat exchanger 15. The gas-liquid separator 40 separates the refrigerant flowing out from the heat exchanger 14 into a gas phase refrigerant and a liquid phase refrigerant. Inside the gas-liquid separator 40, a refrigerant liquid that is a liquid phase refrigerant and a refrigerant vapor that is a gas phase refrigerant are stored. Refrigerant passages 22 and 23 and a refrigerant passage 34 are connected to the gas-liquid separator 40.

  On the outlet side of the heat exchanger 14, the refrigerant is in a gas-liquid two-phase wet steam state in which a saturated liquid and a saturated steam are mixed. The refrigerant that has flowed out of the heat exchanger 14 is supplied to the gas-liquid separator 40 through the refrigerant passage 22. The gas-liquid two-phase refrigerant flowing into the gas-liquid separator 40 from the refrigerant passage 22 is separated into a gas phase and a liquid phase inside the gas-liquid separator 40. The gas-liquid separator 40 separates the refrigerant condensed by the heat exchanger 14 into a liquid refrigerant liquid and a gaseous refrigerant vapor and temporarily stores them.

  The separated refrigerant liquid flows out of the gas-liquid separator 40 via the refrigerant passage 34. The end of the refrigerant passage 34 disposed in the liquid phase in the gas-liquid separator 40 forms an outlet for the liquid-phase refrigerant from the gas-liquid separator 40. The separated refrigerant vapor flows out of the gas-liquid separator 40 via the refrigerant passage 23. An end portion of the refrigerant passage 23 arranged in the gas phase in the gas-liquid separator 40 forms an outlet from the gas-liquid separator 40 for the gas-phase refrigerant. The vapor-phase refrigerant vapor derived from the gas-liquid separator 40 is condensed by releasing heat to the surroundings and cooling in the heat exchanger 15 as the third heat exchanger.

  Inside the gas-liquid separator 40, the refrigerant liquid accumulates on the lower side and the refrigerant vapor accumulates on the upper side. The end portion of the refrigerant passage 34 for leading the refrigerant liquid from the gas-liquid separator 40 is connected to the bottom of the gas-liquid separator 40. Only the refrigerant liquid is sent out of the gas-liquid separator 40 from the bottom side of the gas-liquid separator 40 via the refrigerant passage 34. The end portion of the refrigerant passage 23 for leading the refrigerant vapor from the gas-liquid separator 40 is connected to the ceiling portion of the gas-liquid separator 40. Only the refrigerant vapor is sent out of the gas-liquid separator 40 from the ceiling side of the gas-liquid separator 40 via the refrigerant passage 23. As a result, the gas-liquid separator 40 can reliably separate the gas-phase refrigerant and the liquid-phase refrigerant.

  The path through which the refrigerant flowing from the outlet of the heat exchanger 14 toward the inlet of the expansion valve 16 flows is the refrigerant passage 22 extending from the outlet side of the heat exchanger 14 to the gas-liquid separator 40 and from the gas-liquid separator 40 to the refrigerant. The refrigerant flows into the expansion valve 16 from the outlet side of the heat exchanger 15, the refrigerant passage 23 connected to the inlet side of the heat exchanger 15, and the refrigerant passage 23 through which the steam flows out and flows through the flow rate adjusting valve 28 described later. And a refrigerant passage 25 to be made. The refrigerant passage 23 is a passage through which the gas-phase refrigerant separated by the gas-liquid separator 40 flows.

  The refrigerant path that flows between the heat exchanger 14 and the heat exchanger 15 includes a refrigerant passage 34 that communicates the gas-liquid separator 40 and the cooling unit 30, and a refrigerant that communicates the cooling unit 30 and the refrigerant passage 24. And a passage 36. The refrigerant liquid flows from the gas-liquid separator 40 to the cooling unit 30 via the refrigerant passage 34. The refrigerant that has passed through the cooling unit 30 returns to the refrigerant passage 24 via the refrigerant passage 36. The cooling unit 30 is provided on a refrigerant path that flows from the heat exchanger 14 toward the heat exchanger 15.

  A point D shown in FIG. 2 indicates a connection point of the refrigerant passage 23, the refrigerant passage 24, and the refrigerant passage 36. That is, point D is an end on the downstream side (side close to the heat exchanger 15) of the refrigerant passage 23, an end on the upstream side (side close to the heat exchanger 14) of the refrigerant passage 24, and the refrigerant passage. The downstream end of 36 is shown. The refrigerant passage 23 forms a part of the path through which the refrigerant from the gas-liquid separator 40 to the expansion valve 16 flows, from the gas-liquid separator 40 to the point D.

  The electric device cooling apparatus according to the present embodiment includes a refrigerant path arranged in parallel with the refrigerant path 23, and the cooling unit 30 is provided on the refrigerant path. The cooling unit 30 is provided in one of a plurality of passages connected in parallel in the path of the refrigerant flowing between the heat exchanger 14 and the expansion valve 16 from the gas-liquid separator 40 toward the heat exchanger 15. It has been. The cooling unit 30 includes an EV (Electric Vehicle) device 31 that is an electric device mounted on the vehicle, and a refrigerant passage 32 through which a refrigerant for air conditioning of the passenger compartment flows. The EV device 31 includes a heat source that generates heat during the exercise. One end of the refrigerant passage 32 is connected to the refrigerant passage 34. The other end of the refrigerant passage 32 is connected to the refrigerant passage 36.

  The refrigerant path connected in parallel to the refrigerant passage 23 between the gas-liquid separator 40 and the point D shown in FIG. 2 is the refrigerant on the upstream side (the side close to the gas-liquid separator 40) from the cooling unit 30. The passage 34, the refrigerant passage 32 included in the cooling unit 30, and the refrigerant passage 36 on the downstream side (side closer to the heat exchanger 15) than the cooling unit 30. The refrigerant passage 34 is a passage through which a liquid-phase refrigerant flows from the gas-liquid separator 40 to the cooling unit 30. The refrigerant passage 36 is a passage for circulating the refrigerant from the cooling unit 30 to the point D. Point D is a branch point between the refrigerant passages 23 and 24 and the refrigerant passage 36.

  The refrigerant liquid that has flowed out of the gas-liquid separator 40 flows through the refrigerant passage 34 toward the cooling unit 30. The refrigerant flowing to the cooling unit 30 and flowing via the refrigerant passage 32 takes heat from the heat source included in the EV device 31 as an electric device, and cools the EV device 31. The cooling unit 30 cools the EV device 31 using a liquid-phase refrigerant separated in the gas-liquid separator 40 and flowing to the refrigerant passage 32 via the refrigerant passage 34. In the cooling unit 30, the refrigerant flowing through the refrigerant passage 32 and the heat source included in the EV device 31 exchange heat, whereby the EV device 31 is cooled and the refrigerant is heated. The refrigerant further flows from the cooling unit 30 toward the point D via the refrigerant passage 36 and reaches the heat exchanger 15 via the refrigerant passage 24.

  The cooling unit 30 is provided so as to have a structure capable of exchanging heat between the EV device 31 and the refrigerant in the refrigerant passage 32. The structure of the cooling unit 30 will be described later in detail.

  The EV device 31 is disposed outside the cooling passage 32. In this case, the EV device 31 does not interfere with the flow of the refrigerant flowing through the refrigerant passage 32. For this reason, since the pressure loss of the vapor compression refrigeration cycle 10 does not increase, the EV device 31 can be cooled without increasing the power of the compressor 12.

  The EV device 31 is an electrical device that generates heat when power is transferred. The electrical equipment includes, for example, an inverter for converting DC power to AC power, a motor generator that is a rotating electrical machine, a battery that is a power storage device, a boost converter that boosts the voltage of the battery, and a voltage that lowers the voltage of the battery. It includes at least one of a DC / DC converter and the like. The battery is a secondary battery such as a lithium ion battery or a nickel metal hydride battery. A capacitor may be used instead of the battery.

  The heat exchanger 18 is disposed inside a duct 90 through which air flows. The heat exchanger 18 exchanges heat between the refrigerant and the air-conditioning air flowing through the duct 90 to adjust the temperature of the air-conditioning air. The duct 90 has a duct inlet 91 that is an inlet through which air-conditioning air flows into the duct 90 and a duct outlet 92 that is an outlet through which air-conditioning air flows out from the duct 90. A fan 93 is disposed in the vicinity of the duct inlet 91 inside the duct 90.

  When the fan 93 is driven, air flows in the duct 90. When the fan 93 is in operation, air for air conditioning flows into the duct 90 via the duct inlet 91. The air flowing into the duct 90 may be outside air or air in the vehicle interior. An arrow 95 in FIG. 2 indicates the flow of air-conditioning air that circulates through the heat exchanger 18 and exchanges heat with the refrigerant of the vapor compression refrigeration cycle 10. During the cooling operation, the air-conditioning air is cooled in the heat exchanger 18, and the refrigerant is heated by receiving heat transfer from the air-conditioning air. An arrow 96 indicates the flow of air-conditioning air that is temperature-adjusted by the heat exchanger 18 and flows out of the duct 90 via the duct outlet 92.

  The refrigerant passes through the refrigerant circulation passage in which the compressor 12, the heat exchangers 14 and 15, the expansion valve 16, and the heat exchanger 18 are sequentially connected by the refrigerant passages 21 to 27, and passes through the vapor compression refrigeration cycle 10. Circulate. The refrigerant flows through the vapor compression refrigeration cycle 10 through the points A, B, C, D, E, and F shown in FIG. 2 in order, and the compressor 12 and the heat exchangers 14 and 15 The refrigerant circulates through the expansion valve 16 and the heat exchanger 18.

  FIG. 3 is a Mollier diagram showing the state of the refrigerant in the vapor compression refrigeration cycle in FIG. 2. The horizontal axis in FIG. 3 indicates the specific enthalpy of the refrigerant, and the vertical axis indicates the absolute pressure of the refrigerant. The unit of specific enthalpy is kJ / kg, and the unit of absolute pressure is MPa. The curves in the figure are the saturated vapor line and saturated liquid line of the refrigerant.

  In FIG. 3, the refrigerant flows from the refrigerant passage 22 at the outlet of the heat exchanger 14 into the refrigerant passage 34 via the gas-liquid separator 40, cools the EV device 31, and passes through the point D from the refrigerant passage 36. The thermodynamic state of the refrigerant at each point in the vapor compression refrigeration cycle 10 (ie, points A, B, C, D, E, and F) returning to the refrigerant passage 24 at the inlet of the heat exchanger 15 is shown. The path through which the refrigerant flows, that is, the refrigerant path 21, the refrigerant path 22, the refrigerant path 34, the refrigerant path 36, and the refrigerant paths 24 to 27 form a first path.

  Referring to FIG. 3, the superheated vapor refrigerant (point A) sucked into compressor 12 is adiabatically compressed along isoentropic lines in compressor 12. As the compressor is compressed, the pressure and temperature of the refrigerant rise and become high-temperature and high-pressure superheated steam with a high degree of superheat (point B), and the refrigerant flows to the heat exchanger 14. The gas-phase refrigerant discharged from the compressor 12 is condensed (liquefied) by releasing heat to the surroundings in the heat exchanger 14 and being cooled. By the heat exchange with the outside air in the heat exchanger 14, the temperature of the refrigerant is lowered and the refrigerant is liquefied. The high-pressure refrigerant vapor that has entered the heat exchanger 14 changes from superheated steam to dry saturated vapor while maintaining the same pressure in the heat exchanger 14, releases latent heat of condensation, gradually liquefies, and becomes wet vapor in a gas-liquid mixed state. . Of the refrigerant in the gas-liquid two-phase state, the condensed refrigerant is in a saturated liquid state (point C).

  The refrigerant is separated into a gas phase refrigerant and a liquid phase refrigerant in the gas-liquid separator 40. Among the gas-liquid separated refrigerant, the liquid-phase refrigerant liquid flows from the gas-liquid separator 40 through the refrigerant passage 34 to the refrigerant passage 32 of the cooling unit 30 to cool the EV device 31. In the cooling unit 30, the EV device 31 is cooled by releasing heat to the liquid refrigerant in the saturated liquid state that is condensed after passing through the heat exchanger 14. By the heat exchange with the EV device 31, the refrigerant is heated and the dryness of the refrigerant increases. The refrigerant receives the latent heat from the EV device 31 and partially evaporates to become wet steam in which the saturated liquid and saturated steam are mixed (point D).

  Thereafter, the refrigerant flows into the heat exchanger 15. The wet steam of the refrigerant is condensed again by exchanging heat with the outside air in the heat exchanger 15 and is condensed again. When all of the refrigerant is condensed, it becomes a saturated liquid and further subcooled by releasing sensible heat. Become liquid (point E). Thereafter, the refrigerant flows into the expansion valve 16 via the refrigerant passage 25. In the expansion valve 16, the refrigerant in the supercooled liquid state is squeezed and expanded, the specific enthalpy does not change, the temperature and pressure are reduced, and the low temperature and low pressure gas-liquid mixed vapor is obtained (point F).

  The wet steam refrigerant that has flowed out of the expansion valve 16 flows into the heat exchanger 18 via the refrigerant passage 26. A wet steam refrigerant flows into the tube of the heat exchanger 18. When the refrigerant circulates in the tube of the heat exchanger 18, it absorbs the heat of the air in the vehicle interior via the fins as latent heat of vaporization, and evaporates at a constant pressure. When all the refrigerants are dry and become saturated vapor, the temperature of the refrigerant vapor further rises due to sensible heat and becomes superheated vapor (point A). Thereafter, the refrigerant is sucked into the compressor 12 via the refrigerant passage 27. The compressor 12 compresses the refrigerant flowing from the heat exchanger 18.

  In accordance with such a cycle, the refrigerant continuously repeats the compression, condensation, throttle expansion, and evaporation state changes. In the above description of the vapor compression refrigeration cycle, the theoretical refrigeration cycle is described. However, in the actual vapor compression refrigeration cycle 10, it is necessary to consider the loss in the compressor 12, the pressure loss of the refrigerant, and the heat loss. Of course there is.

  During the operation of the vapor compression refrigeration cycle 10, the refrigerant absorbs heat of vaporization from the air in the vehicle interior when evaporating in the heat exchanger 18 acting as an evaporator, thereby cooling the vehicle interior. In addition, the high-pressure liquid refrigerant that has flowed out of the heat exchanger 14 and separated into gas and liquid by the gas-liquid separator 40 flows to the cooling unit 30, and heat-exchanges with the EV device 31 to cool the EV device 31. The electric device cooling apparatus according to the present embodiment cools an EV device 31 that is a heat source mounted on a vehicle by using a vapor compression refrigeration cycle 10 for air conditioning in a passenger compartment. The temperature required for cooling the EV device 31 is desirably a temperature lower than the upper limit value of the target temperature range as the temperature range of the EV device 31.

  Since the EV equipment 31 is cooled using the vapor compression refrigeration cycle 10 provided to cool the part to be cooled in the heat exchanger 18, a dedicated water circulation pump is used to cool the EV equipment 31. Or it is not necessary to provide equipment, such as a cooling fan. For this reason, since a structure required for the cooling device of the EV equipment 31 can be reduced and the device structure can be simplified, the manufacturing cost of the cooling device can be reduced. In addition, it is not necessary to operate a power source such as a pump or a cooling fan for cooling the EV device 31, and power consumption for operating the power source is not required. Therefore, power consumption for cooling the EV device 31 can be reduced.

  In the heat exchanger 14, it is only necessary to cool the refrigerant to a wet steam state, the refrigerant in the gas-liquid mixed state is separated by the gas-liquid separator 40, and only the refrigerant liquid in the saturated liquid state is supplied to the cooling unit 30. . The refrigerant in the state of wet steam that has received the latent heat of vaporization from the EV device 31 and is partially vaporized is cooled again by the heat exchanger 15. The refrigerant changes its state at a constant temperature until the wet vapor state refrigerant is condensed and completely saturated. The heat exchanger 15 further subcools the liquid refrigerant to a degree of supercooling necessary for cooling the vehicle interior. Since it is not necessary to excessively increase the degree of supercooling of the refrigerant, the capacity of the heat exchangers 14 and 15 can be reduced. Therefore, the cooling capacity for the passenger compartment can be ensured, and the size of the heat exchangers 14 and 15 can be reduced, so that a cooling device for electric equipment that is downsized and advantageous for in-vehicle use can be obtained.

  A refrigerant passage 23 that forms a part of the refrigerant path from the outlet of the heat exchanger 14 to the inlet of the expansion valve 16 is provided between the heat exchanger 14 and the heat exchanger 15. The refrigerant flow from the gas-liquid separator 40 to the expansion valve 16 is a refrigerant path 23 that is a path that does not pass through the cooling unit 30 and a refrigerant path that cools the EV device 31 via the cooling unit 30. The refrigerant passages 34 and 36 and the refrigerant passage 32 are provided in parallel. The cooling system of the EV device 31 including the refrigerant passages 34 and 36 is connected in parallel with the refrigerant passage 23. For this reason, only a part of the refrigerant that has flowed out of the heat exchanger 14 flows to the cooling unit 30. An amount of refrigerant necessary for cooling the EV device 31 is circulated to the cooling unit 30, and the EV device 31 is appropriately cooled. Therefore, it is possible to prevent the EV device 31 from being overcooled.

  A refrigerant path flowing directly from the heat exchanger 14 to the heat exchanger 15 and a refrigerant path flowing from the heat exchanger 14 to the heat exchanger 15 via the cooling unit 30 are provided in parallel, and only a part of the refrigerant is provided. Is allowed to flow through the refrigerant passages 34 and 36, so that pressure loss when the refrigerant flows into the cooling system of the EV device 31 can be reduced. Since all the refrigerant does not flow to the cooling unit 30, it is possible to reduce pressure loss related to the circulation of the refrigerant passing through the cooling unit 30, and accordingly, consumption necessary for the operation of the compressor 12 for circulating the refrigerant. Electric power can be reduced.

  When the low-temperature and low-pressure refrigerant that has passed through the expansion valve 16 is used for cooling the EV device 31, the cooling capacity of the air in the passenger compartment in the heat exchanger 18 decreases, and the cooling capacity for the passenger compartment decreases. In contrast, in the electrical apparatus cooling apparatus according to the present embodiment, in the vapor compression refrigeration cycle 10, the high-pressure refrigerant discharged from the compressor 12 is converted into a heat exchanger 14 as a first condenser, It is condensed by both the heat exchanger 15 as a second condenser. The two-stage heat exchangers 14 and 15 are disposed between the compressor 12 and the expansion valve 16, and the cooling unit 30 that cools the EV device 31 is provided between the heat exchanger 14 and the heat exchanger 15. ing. The heat exchanger 15 is provided on the path of the refrigerant that flows from the cooling unit 30 toward the expansion valve 16.

  The refrigerant heated by receiving the latent heat of vaporization from the EV device 31 is sufficiently cooled in the heat exchanger 15, so that the refrigerant at the outlet of the expansion valve 16 has a temperature originally required for cooling the vehicle interior. And having pressure. For this reason, the amount of heat received from the outside when the refrigerant evaporates in the heat exchanger 18 can be sufficiently increased. Thus, by defining the heat dissipation capability of the heat exchanger 15 that can sufficiently cool the refrigerant, the EV device 31 can be cooled without affecting the cooling capability of cooling the air in the passenger compartment. Therefore, both the cooling capacity of the EV device 31 and the cooling capacity for the passenger compartment can be reliably ensured.

  The refrigerant flowing from the heat exchanger 14 to the cooling unit 30 receives heat from the EV device 31 and is heated when the EV device 31 is cooled. When the refrigerant is heated to the saturated vapor temperature or higher in the cooling unit 30 and the entire amount of the refrigerant is vaporized, the amount of heat exchange between the refrigerant and the EV device 31 is reduced, and the EV device 31 cannot be efficiently cooled. Pressure loss during flow increases. For this reason, it is desirable to cool the refrigerant sufficiently in the heat exchanger 14 so that the entire amount of the refrigerant is not vaporized after the EV device 31 is cooled.

  Specifically, the state of the refrigerant at the outlet of the heat exchanger 14 is brought close to the saturated liquid, and typically, the refrigerant is on the saturated liquid line at the outlet of the heat exchanger 14. As a result of the heat exchanger 14 having the ability to sufficiently cool the refrigerant in this way, the heat dissipating ability for releasing heat from the refrigerant of the heat exchanger 14 is higher than the heat dissipating ability of the heat exchanger 15. By sufficiently cooling the refrigerant in the heat exchanger 14 having a relatively large heat dissipation capability, the refrigerant that has received heat from the EV device 31 can be kept in a wet steam state, and heat exchange between the refrigerant and the EV device 31 can be achieved. Since the decrease in the amount can be avoided, the EV device 31 can be cooled sufficiently efficiently. The refrigerant in the state of wet steam after cooling the EV device 31 is efficiently cooled again in the heat exchanger 15 and cooled to the state of the supercooled liquid below the saturation temperature. Therefore, it is possible to provide a cooling device for an electric device that secures both the cooling capability for the passenger compartment and the cooling capability of the EV device 31.

  The refrigerant in a gas-liquid two-phase state at the outlet of the heat exchanger 14 is separated into a gas phase and a liquid phase in the gas-liquid separator 40. The gas-phase refrigerant separated by the gas-liquid separator 40 flows through the refrigerant passages 23 and 24 and is directly supplied to the heat exchanger 15. The liquid phase refrigerant separated by the gas-liquid separator 40 flows through the refrigerant passage 34 and is supplied to the cooling unit 30 to cool the EV device 31. This liquid-phase refrigerant is a truly saturated liquid refrigerant with no excess or deficiency. By extracting only the liquid-phase refrigerant from the gas-liquid separator 40 and flowing it to the cooling unit 30, the EV device 31 can be cooled by utilizing the capacity of the heat exchanger 14 to the maximum, so that the EV device 31 is cooled. It is possible to provide a cooling device for electric equipment with improved performance.

  By introducing the refrigerant in a saturated liquid state at the outlet of the gas-liquid separator 40 into the refrigerant passage 32 that cools the EV device 31, the refrigerant flows through the cooling system of the EV device 31 including the refrigerant passages 34 and 36 and the refrigerant passage 32. Among the refrigerants, the gas-phase refrigerant can be minimized. For this reason, since the flow velocity of the refrigerant vapor flowing through the cooling system of the EV device 31 can be prevented from increasing and the pressure loss can be suppressed, and the power consumption of the compressor 12 for circulating the refrigerant can be reduced. 10 performance degradation can be avoided.

  A refrigerant liquid in a saturated liquid state is stored inside the gas-liquid separator 40. The gas-liquid separator 40 functions as a liquid accumulator that temporarily stores a liquid refrigerant that is a liquid refrigerant. By storing a predetermined amount of the refrigerant liquid in the gas-liquid separator 40, the flow rate of the refrigerant flowing from the gas-liquid separator 40 to the cooling unit 30 can be maintained even when the load changes. Since the gas-liquid separator 40 has a liquid reservoir function and becomes a buffer against load fluctuations and can absorb the load fluctuations, the cooling performance of the EV device 31 can be stabilized.

  Referring to FIG. 2, the cooling device for electrical equipment in the present embodiment includes a flow rate adjustment valve 28. The flow regulating valve 28 is disposed in the refrigerant passage 23 that forms one of the paths connected in parallel in the refrigerant path from the heat exchanger 14 to the expansion valve 16. The flow rate adjusting valve 28 varies the valve opening degree and increases or decreases the pressure loss of the refrigerant flowing through the refrigerant passage 23, whereby the flow rate of the refrigerant flowing through the refrigerant passage 23 and the cooling system of the EV device 31 including the refrigerant passage 32. The flow rate of the refrigerant flowing through is arbitrarily adjusted.

  For example, when the flow rate adjustment valve 28 is fully closed and the valve opening degree is 0%, the entire amount of the refrigerant that has exited the heat exchanger 14 flows from the gas-liquid separator 40 into the refrigerant passage 34. If the valve opening degree of the flow rate adjustment valve 28 is increased, the flow rate of the refrigerant flowing from the heat exchanger 14 to the refrigerant passage 22 directly flowing to the heat exchanger 15 via the refrigerant passage 23 increases, and the refrigerant passage 34 is The flow rate of the refrigerant that flows to the refrigerant passage 32 via the cooling line and cools the EV device 31 is reduced. If the valve opening degree of the flow rate adjusting valve 28 is reduced, the flow rate of the refrigerant flowing from the heat exchanger 14 to the refrigerant passage 22 directly flowing to the heat exchanger 15 via the refrigerant passage 23 is reduced, and the refrigerant passage 32 is The flow rate of the refrigerant that cools the EV device 31 through the flow increases.

  When the valve opening degree of the flow rate adjusting valve 28 is increased, the flow rate of the refrigerant that cools the EV device 31 is decreased, and the cooling capacity of the EV device 31 is decreased. When the valve opening degree of the flow rate adjusting valve 28 is reduced, the flow rate of the refrigerant that cools the EV device 31 is increased, and the cooling capacity of the EV device 31 is improved. Since the amount of the refrigerant flowing to the EV device 31 can be optimally adjusted using the flow rate adjusting valve 28, the overcooling of the EV device 31 can be reliably prevented, and in addition, the refrigerant of the cooling system of the EV device 31 It is possible to reliably reduce the pressure loss and the power consumption of the compressor 12 for circulating the refrigerant.

  The electric device cooling apparatus according to the present embodiment further includes a refrigerant passage 51. The refrigerant passage 51 is a refrigerant downstream of the cooling unit 30 among the refrigerant passage 21 through which the refrigerant flows between the compressor 12 and the heat exchanger 14 and the refrigerant passages 34 and 36 through which the refrigerant flows through the cooling unit 30. The passage 36 communicates. The refrigerant passage 36 is divided into a refrigerant passage 36 a upstream from the branch with the refrigerant passage 51 and a refrigerant passage 36 b downstream from the branch with the refrigerant passage 51.

  The refrigerant passage 36 and the refrigerant passage 51 are provided with a switching valve 52 that switches the communication state between the refrigerant passage 51 and the refrigerant passages 21 and 36. The switching valve 52 enables or disables the circulation of the refrigerant through the refrigerant passage 51 by switching its opening and closing. By switching the refrigerant path using the switching valve 52, the refrigerant after cooling the EV device 31 passes through the refrigerant passages 36 b and 24 to the heat exchanger 15, or the refrigerant passage 51 and the refrigerant passage 21. Any route to the heat exchanger 14 via can be arbitrarily selected and distributed.

  More specifically, two valves 57 and 58 are provided as the switching valve 52. During the cooling operation of the vapor compression refrigeration cycle 10, the valve 57 is fully opened (valve opening degree 100%), the valve 58 is fully closed (valve opening degree 0%), and the valve opening degree of the flow control valve 28 is set to the cooling unit. 30 is adjusted so that sufficient refrigerant flows. Thereby, the refrigerant | coolant which distribute | circulates the refrigerant path 36a after cooling the EV apparatus 31 can be reliably distribute | circulated to the heat exchanger 15 via the refrigerant path 36b.

  On the other hand, while the vapor compression refrigeration cycle 10 is stopped, the valve 58 is fully opened, the valve 57 is fully closed, and the flow rate adjustment valve 28 is fully closed. As a result, the refrigerant flowing through the refrigerant passage 36 a after cooling the EV device 31 is circulated to the heat exchanger 14 via the refrigerant passage 51, and the cooling unit 30 and the heat exchanger without passing through the compressor 12. 14 can form an annular path for circulating the refrigerant.

  FIG. 4 is a schematic diagram showing a flow of a refrigerant for cooling the EV equipment during operation of the vapor compression refrigeration cycle. FIG. 5 is a schematic diagram showing a flow of a refrigerant that cools the EV equipment while the vapor compression refrigeration cycle is stopped. FIG. 6 is a diagram showing an open / close state of the flow rate adjustment valve and the switching valve in the cooling apparatus for electric equipment according to the embodiment of the present invention.

  Among the operation modes shown in FIG. 6, the “air conditioner operation mode” refers to a case where the vapor compression refrigeration cycle 10 shown in FIG. 4 is operated, that is, the compressor 12 is operated and Is shown. On the other hand, the “heat pipe operation mode” refers to a case where the vapor compression refrigeration cycle 10 shown in FIG. 5 is stopped, that is, the compressor 12 is stopped and an annular path connecting the cooling unit 30 and the heat exchanger 14 is passed. In this case, the refrigerant is circulated.

  Referring to FIGS. 4 and 6, when in the “air conditioner operation mode” in which the compressor 12 is driven and the vapor compression refrigeration cycle 10 is operating, the flow rate adjusting valve 28 allows sufficient refrigerant to flow through the cooling unit 30. Thus, the valve opening is adjusted. The switching valve 52 is operated so that the refrigerant flows from the cooling unit 30 to the expansion valve 16 via the heat exchanger 15. That is, when the valve 57 is fully opened and the valve 58 is fully closed, the refrigerant path is selected so that the refrigerant flows through the entire cooling device. For this reason, while being able to ensure the cooling capacity of the vapor compression refrigeration cycle 10, the EV equipment 31 can be efficiently cooled.

  With reference to FIGS. 5 and 6, when in the “heat pipe operation mode” in which the compressor 12 is stopped and the vapor compression refrigeration cycle 10 is stopped, the refrigerant is circulated from the cooling unit 30 to the heat exchanger 14. The switching valve 52 is operated. That is, the valve 57 is fully closed, the valve 58 is fully opened, and the flow rate adjustment valve 28 is fully closed, whereby the refrigerant flows through the refrigerant passage 51 without flowing from the refrigerant passage 36a to the refrigerant passage 36b. Accordingly, the heat exchanger 14 reaches the cooling unit 30 through the refrigerant passage 22 and the refrigerant passage 34 in order, and further passes through the refrigerant passage 36a, the refrigerant passage 51, and the refrigerant passage 21 in order to the heat exchanger 14. A closed, closed circular path is formed. The path through which the refrigerant flows, that is, the refrigerant path 21, the refrigerant path 22, the refrigerant path 34, the refrigerant path 36a, and the refrigerant path 51 form a second path.

  Via this annular path, the refrigerant can be circulated between the heat exchanger 14 and the cooling unit 30 without operating the compressor 12. When the EV device 31 is cooled, the refrigerant receives evaporation latent heat from the EV device 31 and evaporates. The refrigerant vapor evaporated by heat exchange with the EV device 31 flows to the heat exchanger 14 through the refrigerant passage 36a, the refrigerant passage 51, and the refrigerant passage 21 in order. In the heat exchanger 14, the refrigerant vapor is cooled and condensed by the running air of the vehicle or the ventilation from the condenser fan 42 or the radiator fan for cooling the engine. The refrigerant liquid liquefied by the heat exchanger 14 returns to the cooling unit 30 via the refrigerant passages 22 and 34.

  In this way, a heat pipe is formed by the annular path passing through the cooling unit 30 and the heat exchanger 14, with the EV device 31 as a heating unit and the heat exchanger 14 as a cooling unit. Therefore, even when the vapor compression refrigeration cycle 10 is stopped, that is, when cooling for the vehicle is stopped, the EV device 31 can be reliably cooled without having to start the compressor 12. Since it is not necessary to always operate the compressor 12 for cooling the EV equipment 31, the power consumption of the compressor 12 can be reduced and the fuel consumption of the vehicle can be improved. In addition, the compressor 12 has a long service life. Therefore, the reliability of the compressor 12 can be improved.

  4 and 5 show the ground surface 60. The cooling unit 30 is disposed below the heat exchanger 14 in the vertical direction perpendicular to the ground 60. In an annular path for circulating the refrigerant between the heat exchanger 14 and the cooling unit 30, the cooling unit 30 is disposed below and the heat exchanger 14 is disposed above. The heat exchanger 14 is disposed at a position higher than the cooling unit 30.

  In this case, the refrigerant vapor heated and vaporized in the cooling unit 30 rises in the annular path and reaches the heat exchanger 14, is cooled in the heat exchanger 14, is condensed and becomes a liquid refrigerant, and acts by gravity. It descends in the annular path and returns to the cooling unit 30. That is, the thermosiphon heat pipe is formed by the cooling unit 30, the heat exchanger 14, and the refrigerant path (that is, the second passage) connecting them. Since the heat transfer efficiency from the EV device 31 to the heat exchanger 14 can be improved by forming the heat pipe, the EV can be applied without applying power even when the vapor compression refrigeration cycle 10 is stopped. The device 31 can be cooled more efficiently.

  As the switching valve 52 for switching the communication state between the refrigerant passage 51 and the refrigerant passages 21, 36, the above-described pair of valves 57, 58 may be used, or arranged at a branch between the refrigerant passage 36 and the refrigerant passage 51. It is also possible to use a three-way valve. In any case, the EV apparatus 31 can be efficiently cooled both when the vapor compression refrigeration cycle 10 is operated and when it is stopped. The valves 57 and 58 are inexpensive because they only need to have a simple structure capable of opening and closing the refrigerant passage. By using the two valves 57 and 58, it is possible to provide a cooling structure for electric equipment at a lower cost. it can. On the other hand, it is considered that the space required for the arrangement of the three-way valve may be smaller than the arrangement of the two valves 57 and 58. By using the three-way valve, the electric device having a smaller size and excellent vehicle mountability can be obtained. A cooling structure can be provided.

  The cooling structure for electrical equipment in the present embodiment further includes a check valve 54. The check valve 54 is disposed on the refrigerant passage 21 between the compressor 12 and the heat exchanger 14 on the side closer to the compressor 12 than the connection point between the refrigerant passage 21 and the refrigerant passage 51. The check valve 54 allows the refrigerant flow from the compressor 12 to the heat exchanger 14 and prohibits the reverse refrigerant flow. In this way, in the heat pipe operation mode shown in FIG. 5, a closed loop refrigerant path for circulating the refrigerant between the heat exchanger 14 and the cooling unit 30 can be reliably formed.

  If the check valve 54 is not provided, the refrigerant may flow from the refrigerant passage 51 to the refrigerant passage 21 on the compressor 12 side. Since the check valve 54 is provided, the flow of the refrigerant from the refrigerant passage 51 toward the compressor 12 can be surely prohibited. Therefore, the stop of the vapor compression refrigeration cycle 10 using the heat pipe formed by the annular refrigerant path is used. It is possible to prevent a decrease in the cooling capacity of the EV device 31 at the time. Therefore, the EV device 31 can be efficiently cooled even when the cooling for the passenger compartment of the vehicle is stopped.

  In addition, when the amount of refrigerant in the closed loop refrigerant path is insufficient while the vapor compression refrigeration cycle 10 is stopped, the compressor 12 is operated only for a short time, thereby passing through the check valve 54. Thus, the refrigerant can be supplied to the closed loop path. Thereby, the refrigerant | coolant amount in a closed loop can be increased and the heat exchange processing amount of a heat pipe can be increased. Therefore, since the amount of refrigerant in the heat pipe can be secured, it is possible to avoid insufficient cooling of the EV device 31 due to an insufficient amount of refrigerant.

  That is, the cooling device for electric equipment in the present embodiment constitutes a vapor compression refrigeration cycle, and includes refrigerant passages 21 to 27 as circulation passages through which refrigerant for air conditioning in the passenger compartment circulates, and refrigerant passages 21 to 27. Refrigerant passages 34, 36, 51 serving as communication passages communicating with the refrigerant passage 32, and refrigerant between the refrigerant passages 21 to 27 and the refrigerant passage 32, provided on the passages of the refrigerant passages 34, 36, 51. And a switching valve 52 (valve 57 and valve 58) for allowing or blocking the flow.

  FIG. 7 is a cross-sectional view showing the structure of the cooling unit in FIG. 2 and showing the heat mass cooling mode. FIG. 8 is a cross-sectional view showing the air-conditioner refrigerant cooling mode, which is the structure of the cooling unit in FIG.

  Referring to FIG. 7, the cooling unit 30 includes a heat mass 130, air cooling fins 140, and an A / C (Air Conditioner) refrigerant pipe 120.

  The heat mass 130 is formed of a material having excellent thermal conductivity. The heat mass 130 is made of a metal such as aluminum or copper. The heat mass 130 is formed in a substantially rectangular parallelepiped shape. The heat mass 130 has a front surface 131 and a back surface 136 disposed on the back side thereof. The front surface 131 and the back surface 136 extend in parallel to each other. However, the present invention is not limited to this, and the front surface 131 and the back surface 136 may be formed so as to cross each other on an extension in which the front surfaces extend.

  A plurality of inverter elements 110 are provided on the surface 131. When the EV device 31 in FIG. 2 is an inverter, the inverter element 110 is provided as a heat source included in the inverter. The plurality of inverter elements 110 are arranged on the surface 131 at intervals from each other. The plurality of inverter elements 110 are arranged at equal intervals. The plurality of inverter elements 110 may be arranged at random intervals depending on the heat generation condition of the inverter elements 110. The plurality of inverter elements 110 are provided on the side opposite to the air cooling fins 140 with the heat mass 130 interposed therebetween.

  A plurality of air conditioner refrigerant pipes 120 are further provided on the surface 131. The air conditioner refrigerant pipe 120 forms a refrigerant passage 32 in FIG. 2 through which a refrigerant for air conditioning in the passenger compartment (hereinafter also referred to as an air conditioner refrigerant) flows. The air conditioner refrigerant pipe 120 is disposed between the inverter elements 110 adjacent to each other. The air conditioner refrigerant pipe 120 is disposed at a position equidistant from the two inverter elements 110 provided on both sides thereof.

  Air cooling fins 140 are provided on the back surface 136. The air cooling fin 140 is made of a material having excellent heat conductivity. The air-cooling fin 140 is made of a metal such as aluminum or copper. The air cooling fin 140 protrudes from the back surface 136 and extends in a direction away from the heat mass 130. When the back surface 136 is viewed from the front, the air cooling fins 140 are provided in a region overlapping the region where the plurality of inverter elements 110 are provided. The air cooling fins 140 are supplied with driving air from the vehicle or air from a fan (not shown) as cooling air.

  The inverter element 110 and the air cooling fin 140 are provided on opposite sides of the heat mass 130, and the air conditioner refrigerant pipe 120 and the air cooling fin 140 are provided on the opposite sides of the heat mass 130. The air conditioner refrigerant pipe 120 and the air cooling fin 140 are provided on the opposite side with the heat mass 130 interposed therebetween, and the air conditioner refrigerant pipe 120 and the inverter element 110 are provided on the same side. It is desirable that the distance between the inverter element 110 and the air conditioner refrigerant pipe 120 is smaller than the distance between the air cooling fin 140 and the air conditioner refrigerant pipe 120.

  A heat mass tank 150 is formed in the heat mass 130. The heat mass inner tank 150 is formed by a hollow portion between the front surface 131 and the rear surface 136. When the back surface 136 is viewed from the front, the heat-mass internal tank 150 is provided in a region overlapping the region in which the plurality of inverter elements 110 are provided. A heat transfer medium is disposed in the heat mass tank 150. A heat transfer medium different from the air-conditioner refrigerant flowing in the refrigerant passage 32 is disposed in the heat mass inner tank 150. A heat transfer medium having a specific heat larger than that of the air conditioner refrigerant flowing in the refrigerant passage 32 is disposed in the heat mass inner tank 150. In the present embodiment, cooling water (LLC: long life coolant) is disposed in the heat mass inner tank 150.

  The cooling unit 30 further includes a piston pump 170 and a tank 156. The piston pump 170 discharges the cooling water from the heat mass inner tank 150 to the tank 156 using the pressure of the refrigerant for passenger compartment air conditioning that flows through the refrigerant passage 32 in FIG. The tank 156 is provided in connection with the heat mass tank 150 and stores cooling water.

  The piston pump 170 is connected to the heat mass inner tank 150 and the refrigerant passage 32. The piston pump 170 has a piston 170p that can reciprocate within the cylinder. The air-conditioner refrigerant guided from the refrigerant passage 32 to the piston pump 170 applies pressure to the piston 170p, and when the pressure exceeds a certain value, the piston 170p causes the air-conditioner refrigerant in the heat mass inner tank 150 to be transferred to the tank 156. Operates to extrude. That is, the piston pump 170 is provided so as to operate by detecting the system internal pressure through which the air-conditioning refrigerant circulates.

  The tank 156 has a shape capable of storing cooling water. In the present embodiment, the tank 156 has a bottomed cylindrical shape. The tank 156 may be provided in a vehicle interior in which air-conditioning air whose temperature is adjusted can flow, or may be provided outside the vehicle compartment partitioned from the vehicle interior in which air-conditioning air can flow. As an example of the former, the tank 156 is provided in a cabin that is a passenger space of the vehicle. As an example of the latter, the tank 156 is provided in an engine compartment in which the engine 100 in FIG. 1 is accommodated. In this case, it is preferable that the tank 156 is disposed on the path of the traveling wind flowing into the engine compartment.

  The tank 156 has air cooling fins 157. The air cooling fins 157 are formed in a pleat shape so as to increase the contact area between the tank 156 and the surrounding space. The air cooling fin 157 is provided as a heat radiating part for radiating heat from the cooling water stored in the tank 156 to the space around the tank 156.

  The cooling unit 30 further includes a spring 176 that is an elastic body and a piston 177. The spring 176 and the piston 177 are provided as a supply mechanism that supplies the cooling water stored in the tank 156 to the heat mass tank 150.

  The piston 177 is provided so as to reciprocate within the tank 156. The piston 177 is in contact with the cooling water stored in the tank 156. As the piston 177 reciprocates, the capacity of the cooling water in the tank 156 increases or decreases. The spring 176 applies an elastic force to the piston 177 in a direction in which the piston 177 pushes cooling water from the tank 156.

  In order to avoid the EV device 31 from becoming high temperature and to operate the hybrid system stably, it is necessary to satisfy the cooling capacity of the EV device 31 (inverter in the present embodiment) from the start of the vehicle. However, in the cooling unit 30 that uses air-conditioner refrigerant for cooling the inverter, sufficient refrigerant capacity is obtained until the compressor (compressor) 12 sufficiently compresses the refrigerant and the system of the vapor compression refrigeration cycle 10 is stabilized. May not be secured. In particular, in the heat pipe operation mode, since the inverter is mounted in the upper part of the engine compartment, the refrigerant in the cooling unit 30 is naturally depleted when left for a long period of time, and is long before the start of cooling (refrigerant circulation). It may take time.

  On the other hand, in the cooling apparatus for electrical equipment in the present embodiment, as described above, the piston pump 170 that discharges the cooling water from the heat mass inner tank 150 to the tank 156 using the pressure of the air conditioner refrigerant is provided. Yes. With such a configuration, the heat mass cooling mode in which heat is dissipated from the inverter element 110 in a state in which the heat mass inner tank 150 is filled with cooling water according to the flow state of the air conditioner refrigerant in the refrigerant passage 32, and the inverter element 110 The inverter can be efficiently cooled by selectively using the air-conditioner refrigerant cooling mode in which heat dissipation is performed in a state where the heat mass tank 150 is emptied.

  More specifically, as shown in FIG. 7, the pressure of the air-conditioner refrigerant flowing through the refrigerant passage 32 is low from when the vehicle is started until the system of the vapor compression refrigeration cycle 10 is stabilized. For this reason, the piston pump 170 does not operate and the heat mass inner tank 150 is filled with cooling water. At this time, the heat generated in the inverter element 110 is mainly transmitted through the heat mass 130 and absorbed by the cooling water disposed in the heat mass inner tank 150, and further air-cooled using the cooling water disposed in the heat mass inner tank 150 as a medium. The heat is transmitted to the fin 140 and is radiated to the cooling air supplied to the air cooling fin 140 (heat mass cooling mode).

  Next, as shown in FIG. 8, when the pressure of the air-conditioner refrigerant in the refrigerant passage 32 rises and becomes equal to or higher than a certain value, the piston pump 170 is activated. Thus, while resisting the elastic force of the spring 176 installed in the tank 156, the cooling water is pushed out from the heat mass inner tank 150 to the tank 156, and the heat mass inner tank 150 becomes empty. At this time, the heat generated in the inverter element 110 is mainly transmitted through the heat mass 130 and the air conditioner refrigerant pipe 120 to be radiated to the refrigerant flowing through the refrigerant passage 32 (air conditioner refrigerant cooling mode).

  The cooling water transferred from the heat mass inner tank 150 to the tank 156 radiates heat to the surrounding space of the tank 156 through the air cooling fins 157. When the pressure of the air-conditioner refrigerant in the refrigerant passage 32 decreases, the cooling water in the tank 156 that has become low temperature is pushed out to the heat mass tank 150 by the elastic force of the spring 176 installed in the tank 156. Thereby, the heat mass cooling mode is obtained again.

  As described above, in the present embodiment, since the cooling performance by the air conditioner refrigerant is not sufficient from the time of starting the vehicle until the system of the vapor compression refrigeration cycle 10 is stabilized, the cooling water in the heat mass inner tank 150 is supplied from the inverter element 110. You can earn time by heat dissipation. On the other hand, when the system pressure of the vapor compression refrigeration cycle 10 is increased, cooling with an air-conditioning refrigerant is possible, and thus cooling water is not necessary. For this reason, the cooling water in the heat mass tank 150 is returned to the tank 156 using the pressure of the air conditioner refrigerant.

  FIG. 9 is a cross-sectional view showing a first modification of the cooling apparatus for electric equipment in the embodiment of the present invention. Referring to FIG. 9, in the present modification, a tank 156 </ b> A and a tank 156 </ b> B as a plurality of tanks are provided instead of the tank 156 as compared with the cooling unit 30 in FIGS. 7 and 8. Instead, a plurality of springs 176A and springs 176B as elastic bodies are provided.

  The tank 156B is provided in connection with the tank 150 in the heat mass, and the tank 156A is provided in connection with the tank 156B. The tanks 156A and 156B are provided with pistons 177 that can reciprocate within the tanks. The spring 176A applies an elastic force in a direction in which the piston 177 pushes out the cooling water from the tank 156A to the piston 177 in the tank 156A. The spring 176B applies an elastic force in a direction in which the piston 177 pushes out the cooling water from the tank 156B to the piston 177 in the tank 156B.

  The spring 176A and the spring 176B have different spring constants. The spring constant of the spring 176B is higher than the spring constant of the spring 176A.

  According to this configuration, a relatively large elastic force is applied to the cooling water stored in the tank 156B, and a relatively small elastic force is applied to the cooling water stored in the tank 156A. The cooling water stored in the tank 156B is sent to the heat mass inner tank 150, and then the cooling water stored in the tank 156A is sent to the heat mass inner tank 150. Therefore, the cooling water in the plurality of tanks placed at the ambient temperature can be supplied to the heat mass tank 150 step by step.

  10 and 11 are cross-sectional views showing a second modification of the cooling device for electric equipment in the embodiment of the present invention. FIG. 12 is a block diagram showing a control system in the modification in FIGS. 10 and 11.

  Referring to FIGS. 10 to 12, the cooling device for an electric device according to this modification includes an A / C_ECU (Electronic Control Unit) 190 and a heat mass temperature sensor 160.

  The A / C_ECU 190 controls an air conditioner (A / C, Air Conditioner) mounted on the vehicle, and controls air conditioner refrigerant cooling for cooling the EV device 31. The heat mass temperature sensor 160 is provided as a temperature measurement unit for measuring the temperature of the heat mass 130.

  In the present modification, the heat mass temperature sensor 160 is provided in the heat mass 130 and measures the temperature of the heat mass 130. The heat mass temperature sensor 160 is provided in the vicinity of the surface 131. The distance between the heat mass temperature sensor 160 and the front surface 131 is smaller than the distance between the heat mass temperature sensor 160 and the back surface 136.

  The cooling unit 30 further includes a high-pressure cut valve 181 as a valve mechanism. The high pressure cut valve 181 is provided in the piston pump 170. The high-pressure cut valve 181 operates in response to a command from the A / C_ECU 190 to temporarily reduce the pressure of the air-conditioner refrigerant transmitted to the piston pump 170.

  More specifically, the control of the high-pressure cut valve 181 will be described. First, in the air-conditioner refrigerant cooling mode in which the heat mass tank 150 shown in FIG. taking measurement. A / C_ECU 190 determines whether or not temperature T1 of heat mass 130 is equal to or higher than a predetermined θ1. θ1 is a temperature at which it is determined from the temperature increase rate of the heat mass 130 that the current air-conditioner refrigerant cooling is not in time.

  When T1 <θ1, the temperature of the heat mass 130 is measured again by the heat mass temperature sensor 160 after a predetermined time. On the other hand, when T1 ≧ θ1, the A / C_ECU 190 issues an operation command to the high-pressure cut valve 181. By the operation of the high-pressure cut valve 181, the pressure of the air-conditioner refrigerant transmitted to the piston pump 170 is temporarily reduced. As a result, the piston 170 p is pushed back, and the cooling water flows into the heat mass inner tank 150. As a result, the heat dissipation from the inverter element 110 to the air conditioner refrigerant is added to the cooling water disposed in the heat mass tank 150 and the cooling air supplied to the air cooling fins 140, thereby efficiently cooling the inverter element 110. be able to.

  FIG. 13 is a cross-sectional view showing a structure of a cooling unit for comparison. Referring to FIG. 13, in this comparative example, air conditioner refrigerant pipe 120 is built in heat mass 130. A plurality of inverter elements 110 are provided on the front surface 131, and air cooling fins 140 are provided on the back surface 136. An air conditioner refrigerant pipe 120 is disposed between the inverter element 110 and the air cooling fin 140.

  In the comparative example having such a configuration, the air conditioner refrigerant pipe 120 and the air cooling fin 140 are arranged on the same side as viewed from the inverter element 110. Since the temperature of the refrigerant flowing through the air-conditioner refrigerant pipe 120 is lower than the temperature of the cooling air supplied to the air-cooling fins 140, in this case, the refrigerant flowing through the air-conditioner refrigerant pipe 120 absorbs heat generated by the inverter element 110. In addition to this, a large amount of heat is also absorbed from the cooling air (air) supplied to the air-cooling fins 140. As a result, there is a concern that the heat radiation effect of the heat generated in the inverter element 110 by the air conditioner refrigerant is impaired.

  On the other hand, in the cooling apparatus for electric equipment according to the present embodiment, air conditioner refrigerant pipe 120 and air cooling fin 140 are provided on opposite sides with heat mass 130 interposed therebetween, and air conditioner refrigerant pipe 120 and inverter element 110 are the same. On the side. With such a configuration, it is possible to promote heat dissipation from the inverter element 110 to the air conditioner refrigerant flowing through the air conditioner refrigerant pipe 120 while suppressing heat dissipation from the air cooling fin 140 to the air conditioner refrigerant flowing through the air conditioner refrigerant pipe 120. Thereby, the cooling efficiency of the EV equipment 31 by the air conditioner refrigerant can be improved.

  The structure of the electric device cooling apparatus according to the embodiment of the present invention described above will be described together. The electric device cooling apparatus according to the present embodiment is an EV apparatus 31 as an electric apparatus mounted on a vehicle. It is a cooling device. The electric device cooling apparatus includes a cooling unit 30 for cooling the inverter element 110 as a heat source included in the EV device 31. The cooling unit 30 has a surface 131 as a first surface on which the inverter element 110 is provided and a back surface 136 as a second surface disposed on the back side of the surface 131, and transfers heat generated in the inverter element 110. A heat mass 130 as a heat member, an air cooling fin 140 as a fin portion that is provided on the back surface 136 and dissipates heat transmitted through the heat mass 130, and a refrigerant passage that is provided on the surface 131 and through which a refrigerant for air conditioning of the vehicle compartment flows. And an air conditioner refrigerant pipe 120 as a refrigerant passage forming member for forming the refrigerant. In the heat mass 130, a tank 150 in the heat mass is formed as a heat transfer medium space provided between the front surface 131 and the back surface 136 and in which cooling water as a heat transfer medium different from the refrigerant flowing through the refrigerant passage 32 is arranged. Is done. The cooling unit 30 is provided in connection with the heat mass tank 150 and uses the tank 156 capable of storing the cooling water and the pressure of the refrigerant for the passenger compartment air conditioning to supply the cooling water from the heat mass tank 150 to the tank 156. It further includes a piston pump 170 as a discharge mechanism for discharging.

  According to the electrical apparatus cooling device in the embodiment of the present invention configured as described above, the heat mass cooling mode is used until the air conditioner refrigerant circulates through the refrigerant passage 32, and then the air conditioner refrigerant cooling mode is set. By utilizing, the inverter element 110 can be cooled stably. Further, in the present embodiment, since the pressure of the air conditioner refrigerant is used to discharge the cooling water from the heat mass tank 150, it is possible to switch from the heat mass cooling mode to the air conditioner refrigerant cooling mode without using a water pump. it can.

  In addition, the cooling device of the electric equipment using the air-conditioner refrigerant to which the present invention is applied is not limited to the cooling system shown in FIG. For example, a cooling system in which the heat exchanger 15 is omitted by allowing the heat exchanger 14 to wait for a cooling performance for supercooling the refrigerant may be used, or the heat of the surrounding air may be used for a purpose other than the heat exchanger 18. The heat exchanger that absorbs heat may be a cooling system provided in parallel with the heat exchanger 18.

  Moreover, the cooling device for electric equipment according to the present invention is applicable not only to a hybrid vehicle using an engine and an electric motor as power sources, but also to an electric vehicle using only an electric motor as a power source.

  The embodiment disclosed this time should be considered as illustrative in all points and not restrictive. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

  The present invention is applied to a vehicle such as a hybrid vehicle or an electric vehicle on which electric devices such as a motor generator and an inverter are mounted.

  10 Vapor compression refrigeration cycle, 12 compressor, 14, 15, 18 heat exchanger, 16 expansion valve, 21, 22, 23, 24, 25, 26, 27, 32, 34, 36, 36a, 36b, 51 refrigerant Passage, 28 Flow control valve, 30 Cooling unit, 31 EV equipment, 40 Gas-liquid separator, 42 Condenser fan, 52 Switching valve, 54 Check valve, 57, 58 Valve, 60 Ground, 90 Duct, 91 Duct inlet, 92 Duct outlet, 93 fan, 100 engine, 110 inverter element, 120 air conditioner refrigerant piping, 130 heat mass, 131 front surface, 136 back surface, 140,157 air cooling fin, 150 heat mass tank, 156, 156A, 156B tank, 160 heat mass temperature sensor , 170 piston pump, 170p, 177 piston, 1 6,176A, 176B spring, 181 a high-pressure cut valve 200 drive unit, 400 running battery, 500, 600 cable, 1000 vehicles.

Claims (5)

A cooling device for electric equipment mounted on a vehicle,
It has a cooling part for cooling the heat source included in the electrical equipment,
The cooling part is
A heat transfer member having a first surface on which the heat generation source is provided and a second surface disposed on the back side of the first surface, and transferring heat generated by the heat generation source;
A fin portion provided on the second surface for radiating heat transferred through the heat transfer member;
A refrigerant passage forming member that is provided on the first surface and forms a refrigerant passage through which a refrigerant for vehicle compartment air conditioning flows.
The heat transfer member is provided with a heat transfer medium space provided between the first surface and the second surface and in which a heat transfer medium different from the refrigerant flowing through the refrigerant passage is disposed,
The cooling part is
A tank provided in connection with the heat transfer medium space and capable of storing the heat transfer medium;
A cooling device for an electrical device, further comprising: a discharge mechanism that discharges the heat transfer medium from the heat transfer medium space to the tank using a pressure of a refrigerant for air conditioning in the passenger compartment. The discharge mechanism includes a piston pump that is connected to the heat transfer medium space and is acted on by a refrigerant pressure for vehicle compartment air conditioning.
2. The cooling device for an electric device according to claim 1, wherein the piston pump operates to push out a heat transfer medium from the heat transfer medium space when a pressure of a refrigerant for air conditioning in the passenger compartment reaches a predetermined value or more. .   The cooling device for an electric device according to claim 1, wherein the cooling unit further includes a valve mechanism that temporarily reduces a pressure of a refrigerant for passenger compartment air conditioning transmitted to the discharge mechanism unit. A temperature measuring unit for measuring the temperature of the heat transfer member;
A control unit for controlling the operation of the valve mechanism based on the temperature T1 measured by the temperature measurement unit;
When the value of T1 is equal to or greater than θ1 (θ1 is a preset threshold value), the control unit reduces the pressure of the refrigerant for vehicle compartment air conditioning transmitted to the discharge mechanism unit. The apparatus for cooling an electric device according to claim 3, wherein the mechanism is operated.   5. The cooling device for an electric device according to claim 1, wherein the tank includes a heat radiating portion that radiates heat from a heat transfer medium stored in the tank to the periphery of the tank. 6.

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