Electric compressor and thermal management system

Abstract

An electric compressor is provided with a casing (19), an electric motor (11), a refrigerant compression unit (12), an electric control unit (26), a refrigerant flow path (25), and a cooling water flow path (2). The motor (11) is rotationally driven by energizing the winding (32). The refrigerant compression unit (12) sucks in, compresses, and discharges refrigerant by being driven by the electric motor (11). The electrical control unit (26) has an electronic component (27) that generates heat by energization, and controls energization to the winding (32) of the motor (11). A refrigerant flow path (25) provided inside the casing (19) is provided so as to enable heat exchange between the low-temperature and low-pressure refrigerant before being sucked into the refrigerant compression unit (12), the winding (32), and the electronic component (27). A cooling water flow path (20) provided on the inside of the housing (19) is provided so as to enable heat exchange between the cooling water flowing through the cooling water flow path (20), the winding (32), and the electronic component (27).

Description

[0001] Cross-reference to related applications

[0002] This application is based on Japanese Patent Application No. 2022-120624 filed on July 28, 2022, and the contents thereof are incorporated by reference. Technical Field

[0003] The present disclosure relates to an electric compressor used in a refrigeration cycle device, and a thermal management system including the refrigeration cycle device and a cooling water circuit. Background Art

[0004] Conventionally, electric compressors used in refrigeration cycle devices are known.

[0005] The electric compressor described in Patent Document 1 has a structure in which a motor and a refrigerant compression unit are provided inside a casing, and an electric control unit for driving and controlling the motor is provided outside the casing. The electric compressor cools the winding of the motor by low-temperature and low-pressure refrigerant flowing inside the casing, and further cools the switching elements and the like of the inverter circuit of the electric control unit through the casing by the refrigerant.

[0006] Prior art literature

[0007] Patent Literature

[0008] Patent Document 1: Japanese Patent Application Publication No. 2003-322082

[0009] However, in a configuration in which the electric motor and the electric control unit are cooled only by the refrigerant as in the electric compressor described in Patent Document 1, there are the following technical problems.

[0010] First, when the heat of the refrigerant flowing through the condenser of the refrigeration cycle device is used for heating when the outside air is extremely low, the temperature of the refrigerant must be lower than the outside air temperature in order to absorb heat from the outside air to the refrigerant in the evaporator. For this reason, when the temperature of the refrigerant sucked from the evaporator to the electric compressor is lower than the low-temperature side allowable temperature (e.g. -40°C) of the electronic components of the electrical control unit, there is a concern that the electronic components may malfunction. In addition, there is a concern that the use of the refrigeration cycle for heating, etc., may be hindered in order to protect the electronic components.

[0011] Next, when the electric compressor is rotated at a low speed under the operating conditions of the refrigeration cycle device, the refrigerant flow rate decreases, and the cooling capacity of the refrigerant relative to the motor windings decreases. At this time, under the operating conditions where the motor needs to output torque at a high load, the temperature of the windings rises due to the increase in current, and there is a concern that the temperature of the windings will be higher than the protection temperature of the windings themselves. For this reason, it is necessary to change the operating point of the electric compressor, or to perform control such as temporarily stopping the electric compressor so that the temperature of the windings does not exceed its protection temperature, and there is a concern that the operating range of the electric compressor will be limited.

[0012] Furthermore, in general, the refrigerant used in the refrigeration cycle has a large temperature difference between low temperature and high temperature. Therefore, when the temperature change of the electronic components that exchange heat with the refrigerant becomes large, there is a concern that the life of the electronic components will be shortened. Summary of the invention

[0013] The purpose of the present disclosure is to prevent the temperature of electronic components from falling below the allowable temperature on the low temperature side when the outside air is extremely low in an electric compressor and a thermal management system, and to suppress the situation where the operating area is limited for winding protection when the electric compressor rotates at a low speed and under a high load.

[0014] According to one aspect of the present disclosure, an electric compressor used in a refrigeration cycle device includes a casing, an electric motor, a refrigerant compression unit, an electrical control unit, a refrigerant flow path, and a cooling water flow path. The casing constitutes an outer shell. The electric motor is disposed on the inner side of the casing and is rotationally driven by energizing the windings. The refrigerant compression unit sucks in, compresses, and discharges refrigerant by being driven by the electric motor. The electrical control unit has electronic components that generate heat by energizing, and controls the energization of the windings of the motor. The refrigerant flow path disposed on the inner side of the casing is configured to enable heat exchange between the low-temperature and low-pressure refrigerant, the windings, and the electronic components before being sucked into the refrigerant compression unit. The cooling water flow path disposed on the inner side of the casing is configured to enable heat exchange between the cooling water, the windings, and the electronic components flowing in the cooling water flow path.

[0015] Based on this, the windings and electronic components can exchange heat with the refrigerant flowing in the refrigerant flow path, and can also exchange heat with the cooling water flowing in the cooling water flow path. Therefore, when the outside air is extremely low temperature and the refrigeration cycle device is used for heating, even if the refrigerant temperature in the refrigerant flow path is lower than the low temperature side allowable temperature of the electronic components, the heat exchange between the cooling water and the electronic components can prevent the temperature of the electronic components from being lower than the low temperature side allowable temperature.

[0016] Furthermore, when the electric compressor rotates at a low speed and under a high load in the operating conditions of the refrigeration cycle device, even if the refrigerant flow rate is reduced to reduce the cooling capacity of the refrigerant to the winding, the temperature of the winding can be prevented from being higher than its own protection temperature through heat exchange between the cooling water and the winding. For this reason, the control of changing the working point of the electric compressor can be suppressed in such a way that the temperature of the winding does not exceed its own protection temperature, or the control of temporarily stopping or intermittently operating the electric compressor can be suppressed. Therefore, the situation where the operating area of ​​the electric compressor is limited can be suppressed.

[0017] Furthermore, generally, the temperature difference between the cooling water flowing in the cooling water flow path at low temperature and high temperature is smaller than the temperature difference between the refrigerant flowing in the refrigerant flow path at low temperature and high temperature. Therefore, the structure in which the cooling water flowing in the cooling water flow path and the electronic components perform heat exchange can suppress the temperature change of the electronic components. Therefore, the life of the electronic components can be extended.

[0018] In the present disclosure, the electric compressor is not limited to the one including the above-mentioned electric motor and refrigerant compression unit, and may be an electric compressor including various components of a refrigeration cycle device such as an accumulator and an oil separator as a whole, for example.

[0019] Furthermore, another aspect of the present disclosure relates to a thermal management system having a refrigeration cycle device and a cooling water circuit (4). The refrigeration cycle device is configured to connect the electric compressor described in one aspect of the present disclosure, a high-temperature side refrigerant-cooling water heat exchanger for performing heat exchange between the refrigerant discharged from the refrigerant compression unit of the electric compressor and the cooling water, an expansion valve for decompressing and expanding the refrigerant flowing out of the high-temperature side refrigerant-cooling water heat exchanger, and a low-temperature side refrigerant-heat medium heat exchanger for performing heat exchange between the refrigerant flowing out of the expansion valve and the heat medium through a refrigerant piping, so that the refrigerant circulates. The cooling water circuit connects the high-temperature side cooling water-air heat exchanger for performing heat exchange between the cooling water and the air, the high-temperature side refrigerant-cooling water heat exchanger, and a cooling water pump through a cooling water piping, so that the cooling water flow path of the electric compressor is a flow path for cooling water to flow from the high-temperature side cooling water-air heat exchanger to the high-temperature side refrigerant-cooling water heat exchanger.

[0020] Based on this, the cooling water flowing from the "high-temperature side cooling water-air heat exchanger" to the "high-temperature side refrigerant-cooling water heat exchanger" is the cooling water before it dissipates heat to the air in the "high-temperature side cooling water-air heat exchanger" and absorbs heat from the refrigerant in the "high-temperature side refrigerant-cooling water heat exchanger". For this reason, by using cooling water on the upstream side of the "high-temperature side refrigerant-cooling water heat exchanger", the cooling efficiency of the cooling water on the winding can be improved compared to using cooling water on the downstream side of the "high-temperature side refrigerant-cooling water heat exchanger", and the amount of heat absorbed by the cooling water from the winding can be increased. Therefore, the winding can be cooled, and the efficiency of the thermal management system can be improved by making the temperature of the cooling water circulating in the cooling water circuit higher.

[0021] In addition, the reference symbols in parentheses given to each component etc. show an example of the correspondence relationship between the component etc. and the specific component etc. described in the embodiment described later. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 It is a diagram showing a schematic configuration of a thermal management system including an electric compressor according to the first embodiment.

[0023] Figure 2 It is a cross-sectional view showing a schematic structure of an electric compressor.

[0024] Figure 3 yes Figure 2 Cross-sectional view along line III-III.

[0025] Figure 4 This is a graph showing the relationship between the refrigerant temperature and the temperature of electronic components immediately after startup in an extremely low temperature environment in an electric compressor of a comparative example.

[0026] Figure 5 This is a graph showing the relationship among the refrigerant temperature, the cooling water temperature, and the temperature of the electronic components immediately after startup in an extremely low temperature environment in the electric compressor according to the first embodiment.

[0027] Figure 6 This is a graph showing the relationship between the winding temperature of the electric motor and the refrigerant temperature under the operating conditions of low-speed rotation and high load in the electric compressor of the comparative example.

[0028] Figure 7 This is a graph showing the relationship between the winding temperature of the electric motor and the refrigerant temperature under the operating conditions of low-speed rotation and high load in the electric compressor according to the first embodiment.

[0029] Figure 8 This is a graph for explaining the operating range of the electric compressor.

[0030] Fig. 9This is a flowchart showing an example of control processing executed by the electronic control device when the thermal management system is started.

[0031] Fig.10 This is a flowchart showing an example of control processing executed by the electronic control device when the thermal management system is stopped.

[0032] Fig.11 This is a flowchart showing an example of a control process executed by the electronic control device of the thermal management system according to the second embodiment. DETAILED DESCRIPTION

[0033] Hereinafter, embodiments of the present disclosure will be described with reference to the drawings. In the following embodiments, identical or equivalent parts are denoted by the same reference numerals and their descriptions are omitted.

[0034] (First Embodiment)

[0035] The first embodiment will be described with reference to the accompanying drawings. Figure 1 As shown, the electric compressor 1 according to the first embodiment is used in a thermal management system 2 mounted on a vehicle.

[0036] <Structure of thermal management system 2>

[0037] First, the structure of the thermal management system 2 is described. Figure 1 As shown, the thermal management system 2 includes a refrigeration cycle device 3, a first cooling water circuit 4, a second cooling water circuit 5, and an electronic control unit 6 (hereinafter referred to as "ECU 6"). ECU is an abbreviation of Electronic Control Unit. In addition, the first cooling water circuit 4 is equivalent to an example of a "cooling water circuit".

[0038] The refrigeration cycle device 3 is a vapor compression refrigeration cycle composed of a refrigerant pipe 10 that connects an electric compressor 1, a high-temperature side refrigerant-cooling water heat exchanger 7, an expansion valve 8, and a low-temperature side refrigerant-cooling water heat exchanger 9, etc., so as to circulate the refrigerant. The low-temperature side refrigerant-cooling water heat exchanger 9 is an example of a "low-temperature side refrigerant-heat medium heat exchanger". As the refrigerant circulating in the refrigeration cycle device 3, for example, an HFC refrigerant (for example, R134a) or an HFO refrigerant (for example, R1234yf) is used. In addition, a natural refrigerant (for example, carbon dioxide) or the like can also be used as the refrigerant. Figure 1 The arrow RF indicates the direction in which the refrigerant flows in the refrigerant pipe 10 .

[0039] The electric compressor 1 includes an electric motor 11 and a refrigerant compression unit 12. The electric motor 11 is driven to rotate by power supply. The refrigerant compression unit 12 is driven by the electric motor 11 to compress the refrigerant sucked from the refrigerant suction port 13 and discharge it from the refrigerant discharge port 14. As the refrigerant compression unit 12, either a fixed capacity type or a variable capacity type may be adopted. The specific structure of the electric compressor 1 will be described later.

[0040] The high-temperature and high-pressure refrigerant discharged from the electric compressor 1 flows into the high-temperature side refrigerant-cooling water heat exchanger 7. The high-temperature side refrigerant-cooling water heat exchanger 7 is a heat exchanger that performs heat exchange with the cooling water circulating in the refrigerant and the first cooling water circuit 4. The high-temperature side refrigerant-cooling water heat exchanger 7 is also called a water-cooled condenser. The refrigerant flowing in the high-temperature side refrigerant-cooling water heat exchanger 7 dissipates heat to the cooling water and condenses.

[0041] The refrigerant flowing out of the high-temperature side refrigerant-cooling water heat exchanger 7 is decompressed and expanded when passing through the expansion valve 8, becomes a gas-liquid two-phase state, and flows into the low-temperature side refrigerant-cooling water heat exchanger 9. As the expansion valve 8, a variable throttle valve such as a temperature expansion valve or an electronic expansion valve or a fixed throttle valve may be used.

[0042] The low-temperature side refrigerant-cooling water heat exchanger 9 is a heat exchanger that performs heat exchange between the refrigerant and the cooling water circulating in the second cooling water circuit 5. In addition, the cooling water flowing in the low-temperature side refrigerant-cooling water heat exchanger 9 (that is, the cooling water circulating in the second cooling water circuit 5) is equivalent to an example of "heat medium". The low-temperature side refrigerant-cooling water heat exchanger 9 is also called a cooler. The refrigerant flowing in the low-temperature side refrigerant-cooling water heat exchanger 9 absorbs heat from the cooling water and evaporates. The refrigerant flowing out of the low-temperature side refrigerant-cooling water heat exchanger 9 is sucked into the refrigerant suction port 13 of the electric compressor 1.

[0043] The first cooling water circuit 4 is a circuit formed by connecting the high-temperature side refrigerant-cooling water heat exchanger 7, the high-temperature side cooling water-air heat exchanger 16, the first cooling water pump 17, etc. by a cooling water pipe 18 so as to circulate cooling water. The first cooling water pump 17 is an example of a "cooling water pump". Antifreeze solution (i.e., LLC) is used as cooling water circulating in the first cooling water circuit 4. LLC is the abbreviation of Long Life Coolant. Figure 1 The arrow WF indicates the direction in which the cooling water flows in the cooling water pipe 18 .

[0044] The high temperature side refrigerant-cooling water heat exchanger 7 has been described in the refrigeration cycle device 3. The cooling water flowing through the high temperature side refrigerant-cooling water heat exchanger 7 absorbs heat from the refrigerant and is heated.

[0045] The high-temperature side cooling water-air heat exchanger 16 is a heat exchanger that performs heat exchange between cooling water and air. The air heated in the high-temperature side cooling water-air heat exchanger 16 is used, for example, in vehicle interior air conditioning (specifically, heating, etc.). This high-temperature side cooling water-air heat exchanger 16 is also called a heater core. In addition, the cooling water flowing in the high-temperature side cooling water-air heat exchanger 16 dissipates heat to the air and is cooled. The cooling water flowing out of the high-temperature side cooling water-air heat exchanger 16 flows in the cooling water flow path 20 provided on the inner side of the casing 19 of the electric compressor 1, and then flows into the high-temperature side refrigerant-cooling water heat exchanger 7. The structure and function effect of the cooling water flow path 20 will be described later.

[0046] The first cooling water pump 17 is an electric water pump. When the first cooling water pump 17 is driven, cooling water circulates in the first cooling water circuit 4 .

[0047] The second cooling water circuit 5 is configured to circulate cooling water by connecting the low-temperature side refrigerant-cooling water heat exchanger 9, the low-temperature side cooling water-air heat exchanger 22, the second cooling water pump 23, etc., by a cooling water pipe 24. An antifreeze solution (i.e., LLC) is used as the cooling water circulating in the second cooling water circuit 5.

[0048] The low-temperature-side refrigerant-cooling water heat exchanger 9 has been described in the refrigeration cycle device 3. The cooling water flowing through the low-temperature-side refrigerant-cooling water heat exchanger 9 transfers heat to the refrigerant to be cooled.

[0049] The low temperature side coolant-air heat exchanger 22 is a heat exchanger for performing heat exchange between coolant and air. The air cooled by the low temperature side coolant-air heat exchanger 22 is used in, for example, a vehicle interior air conditioner (specifically, a cooling room, etc.).

[0050] The second cooling water pump 23 is an electric water pump. The second cooling water pump 23 is driven to circulate cooling water in the second cooling water circuit 5 .

[0051] ECU6 has a microcomputer and its peripheral circuits. The microcomputer has a processor for performing control processing and calculation processing, and a memory for storing programs, data, etc. The processor is composed of a CPU and an MPU. The memory has various non-transient physical storage media such as ROM, RAM, and non-volatile rewritable memory. ECU6 controls the driving of the electric compressor 1, the first cooling water pump 17, the second cooling water pump 23, etc. by executing the program stored in the memory through the processor. The control processing performed by this ECU6 will be described later.

[0052] Although not shown in the figure, the thermal management system 2 may include another cooling water circuit or heat medium circuit in addition to the first cooling water circuit 4 and the second cooling water circuit 5. Furthermore, the battery or host of the vehicle may be cooled or heated by the cooling water circuit or heat medium circuit.

[0053] <Structure of the electric compressor 1>

[0054] Next, the specific structure of the electric compressor 1 will be described. Figure 2 and Figure 3 As shown, the electric compressor 1 includes a casing 19 , a refrigerant flow path 25 , a cooling water flow path 20 , an electric motor 11 , a refrigerant compression unit 12 , an electric control unit 26 , and the like.

[0055] The housing 19 is formed of metal or the like, and constitutes the outer shell of the electric compressor 1. The housing 19 is a closed container structure in which a plurality of components are joined. A refrigerant flow path 25, a cooling water flow path 20, the motor 11, and the refrigerant compression unit 12 are provided inside the housing 19.

[0056] As described above, the refrigerant flow path 25 is a flow path for the low-temperature and low-pressure gas-phase refrigerant that flows out from the low-temperature side refrigerant-cooling water heat exchanger 9 of the refrigeration cycle device 3 and is sucked into the refrigerant compression part 12. The refrigerant flow path 25 is formed as a space for the motor 11 to be arranged inside the casing 19. Therefore, the refrigerant flowing in the refrigerant flow path 25 flows in the gaps between the various structural components of the motor 11, and can cool the motor 11 by directly exchanging heat with the various structural components of the motor 11. In addition, the refrigerant flowing in the refrigerant flow path 25 can cool the electronic components 27 by exchanging heat with the electronic components 27 of the electrical control part 26 through the casing 19. The refrigerant flow path 25 is configured so that the refrigerant flowing in the refrigerant flow path 25 is sucked into the refrigerant compression part 12.

[0057] As described above, the cooling water flow path 20 is a flow path for the cooling water that flows out of the high-temperature side cooling water-air heat exchanger 16 of the first cooling water circuit 4 and flows before flowing into the high-temperature side refrigerant-cooling water heat exchanger 7. The cooling water flow path 20 is formed so that the cooling water flows to a hole formed on the inner side of the casing 19. The hole constituting the cooling water flow path 20 is formed in a portion between the motor 11 and the electrical control unit 26 in the casing 19. Therefore, the cooling water flowing in the cooling water flow path 20 can perform heat exchange with the various structural components of the motor 11 via the casing 19. Moreover, the cooling water flowing in the cooling water flow path 20 can perform heat exchange with the electronic components 27 and the like of the electrical control unit 26 via the casing 19.

[0058] The motor 11 is provided inside the refrigerant flow path 25 formed inside the housing 19. As the motor 11, various types of motors such as a DC motor or an AC motor can be used. In this embodiment, for example, a brushless motor is used. The motor 11 has a stator 28, a rotor 29, and a shaft 30.

[0059] The stator 28 includes a stator core 31 and a winding 32. The stator core 31 includes a cylindrical outer peripheral portion 33 and a plurality of teeth 34 extending radially inward from the outer peripheral portion 33. The stator core 31 is fixed to the inner wall 251 of the refrigerant flow path 25. The winding 32 is wound in the slits formed between the plurality of teeth 34. The winding 32 is a three-phase winding such as a Δ connection or a Y connection.

[0060] The rotor 29 has a rotor core 35 and a plurality of magnets 36, and is arranged to be rotatable together with the shaft 30 inside the stator 28. The shaft 30 is provided at the center of the rotor 29. An end portion 37 of the shaft 30 extending from the rotor 29 to the side opposite to the refrigerant compression section 12 is rotatably supported on a first bearing 38 provided in the casing 19. A portion 39 of the shaft 30 extending from the rotor 29 to the refrigerant compression section 12 side is rotatably supported on a second bearing 41 provided in an intermediate support portion 40 fixed in the casing 19.

[0061] An eccentric portion 42 is provided at a portion of the shaft 30 that extends further toward the refrigerant compression section 12 than the second bearing 41. The eccentric portion 42 is formed in a cylindrical shape whose center position is offset relative to the axis CL of the shaft 30, and is slidably engaged with a bearing portion 44 having a movable scroll 43 provided in the refrigerant compression section 12. For this reason, the torque output by the motor 11 is transmitted from the shaft 30 to the movable scroll 43, and the movable scroll 43 performs an orbital motion with the axis CL of the shaft 30 as the center of the orbit.

[0062] As described above, the refrigerant flowing in the refrigerant flow path 25 flows in the gaps between the components of the motor 11 (for example, the gaps between the stator 28 and the rotor 29). Although not shown in the figure, the refrigerant flow path 25 may be a flow path for the refrigerant to flow toward the outer periphery of the stator 28, or a flow path for the refrigerant to flow toward the rotor 29 or the shaft 30.

[0063] The refrigerant compression unit 12 is driven by the motor 11. As the refrigerant compression unit 12, various types such as rotary, reciprocating, and variable capacity can be adopted. In the present embodiment, for example, a scroll compressor among rotary types is adopted. Therefore, the refrigerant compression unit 12 has a fixed scroll 45 and a movable scroll 43.

[0064] The fixed scroll 45 includes a fixed disk 46 and a spiral fixed wrap 47 provided on the fixed disk 46. The fixed disk 46 is fixed to the casing 19. The fixed wrap 47 is provided so as to protrude from the fixed disk 46 toward a movable disk 48 of the movable scroll 43.

[0065] The movable scroll 43 has a movable disk 48 arranged opposite to the fixed disk 46, and a spiral movable wrap 49 provided on the movable disk 48. The movable wrap 49 is provided to protrude from the movable disk 48 to the fixed disk 46 side. The fixed wrap 47 and the movable wrap 49 are provided to be fitted with each other. The movable scroll 43 is provided with a non-illustrated self-rotation prevention mechanism for preventing self-rotation. For this reason, the movable scroll 43 does not rotate but revolves around the axis CL of the shaft 30 as the center of the revolution.

[0066] A working chamber 50 is formed between the fixed scroll 45 and the movable scroll 43. Moreover, a refrigerant suction port 13 is formed on the radially outer side of the movable scroll 43 on the inner side of the outer peripheral wall of the fixed scroll 45. The refrigerant suction port 13 is connected to the refrigerant flow path 25. When the movable scroll 43 revolves by the drive of the motor 11, the refrigerant is sucked into the working chamber 50 from the refrigerant suction port 13, and the refrigerant is compressed by the reduction of the volume of the working chamber 50.

[0067] A refrigerant discharge port 14 is provided at the fixed disk 46 of the fixed scroll 45, through which the refrigerant compressed in the working chamber 50 is discharged. The refrigerant discharge port 14 is communicated with the discharge space 51. A discharge check valve 52 is provided between the refrigerant discharge port 14 and the discharge space 51. The refrigerant discharged from the refrigerant discharge port 14 to the discharge space 51 is discharged from a discharge port 53 provided in the casing 19.

[0068] The electric control unit 26 controls the energization of the motor 11 to the winding 32. The electric control unit 26 has a substrate 55, an IC (i.e., integrated circuit) 56, a filter 57, and a plurality of switching elements 58 on the inner side of a housing 54. The circuit including the IC 56 is mounted relative to the substrate 55. The filter 57 is composed of, for example, a smoothing capacitor, etc., and suppresses the fluctuation of the voltage supplied from the battery of the vehicle not shown. The plurality of switching elements 58, for example, constitute an inverter circuit for making a three-phase AC supplied from the motor 11 to the winding 32.

[0069] like Figure 2As shown, in the electrical control unit 26, the filter 57 and the switch element 58, etc., which are the electronic components 27 that generate heat when energized, are arranged at a position closer to the cooling water flow path 20 than the center position CP of the electrical control unit 26. In addition, the electronic components 27 that generate heat when energized (i.e., the filter 57 and the switch element 58, etc.) are directly connected to the housing 19, or indirectly connected via a heat conduction component not shown. For this reason, the electronic components 27 that generate heat when energized can exchange heat with the refrigerant flowing in the refrigerant flow path 25, and can exchange heat with the cooling water flowing in the cooling water flow path 20.

[0070] Moreover, if Figure 2 and Figure 3 As shown in FIG. 1 , the electronic component 27 that generates heat by energizing and the cooling water flow path 20 formed in the housing 19 are arranged in a manner facing each other. Figure 2 As shown, the distance D1 between the electronic component 27 generating heat by energization and the cooling water flow path 20 is closer than the distance D2 between the electronic component 27 generating heat by energization and the refrigerant flow path 25. Thus, the heat exchange efficiency between the plurality of electronic components 27 generating heat by energization and the cooling water flowing in the cooling water flow path 20 can be improved.

[0071] In the above configuration, when the electric control unit 26 supplies power to the winding 32 of the motor 11, a rotating magnetic field is generated in the stator 28, and the rotor 29 and the shaft 30 are driven to rotate. The rotational motion of the shaft 30 is transmitted to the movable scroll 43. The refrigerant sucked into the working chamber 50 of the refrigerant compression unit 12 from the refrigerant flow path 25 is compressed due to the reduction in the volume of the working chamber 50 by the orbital motion of the movable scroll 43, and is discharged from the refrigerant discharge port 14 through the discharge space 51 and from the discharge port 53. Thus, the refrigeration cycle device 3 is operated.

[0072] <Function and Effect of Cooling Water Flow Path 20>

[0073] Next, the effect of providing the cooling water flow path 20 on the inner side of the housing 19 in the electric compressor 1 of this embodiment will be described while comparing it with the electric compressor of the comparative example. In addition, the electric compressor of the comparative example has the same structure as the first embodiment except that the cooling water flow path 20 is not provided for the electric compressor 1 of the first embodiment.

[0074] <Temperature of electronic components 27>

[0075] Figure 4 and Figure 5 The graph shows the relationship between the refrigerant temperature and the temperature of the electronic component 27 immediately after the electric compressor is started (i.e., immediately after the refrigeration cycle device 3 is started) when the outside air is extremely low temperature (eg, -35°C) and the heat management system 2 is used for heating or the like.

[0076] Figure 4 (A) Figure 5 The solid lines A and D in (A) represent the temperature of the electronic component 27, specifically, the temperature of the switching element 58 constituting the inverter circuit in the electric control unit 26. Figure 4 (A) Figure 5 The dashed lines B and F in (A) represent the temperature of the refrigerant flowing in the refrigerant flow path 25 of the electric compressor, that is, the temperature of the refrigerant flowing out of the low-temperature side refrigerant-cooling water heat exchanger 9 of the refrigeration cycle device 3 and before being sucked into the refrigerant compression unit 12. Figure 5 The dotted line E in (A) represents the temperature of the refrigerant flowing in the cooling water flow path 20 of the electric compressor 1 in the first embodiment, that is, the temperature of the cooling water flowing out of the high-temperature side cooling water-air heat exchanger 16 of the first cooling water circuit 4 and before flowing into the high-temperature side refrigerant-cooling water heat exchanger 7. Figure 4 (B) Figure 5 Solid lines C and G in (B) indicate the rotation speed of the electric compressor 1 .

[0077] Figure 4 denoted as a comparative example of an electric compressor. Figure 4 As shown in (A), the period from time T0 to T1 is the state before the electric compressor of the comparative example is started, and the temperature of the electronic component 27 shown by the solid line A and the temperature of the refrigerant shown by the single-dot chain line B are at the same level as the outside air temperature (for example, -35°C). Figure 4 As shown by the solid line C in (B), the electric compressor starts at time T1 (i.e., the refrigeration cycle starts at time T1), and operates at a constant speed after time T2. Figure 4 As shown by the dashed line B in (A), the refrigerant temperature drops significantly (eg, about -50°C) from the outside air temperature from time T1 to time T3, and then remains substantially constant after time T3. Thus, the refrigeration cycle device 3 can absorb heat from the outside air to the refrigerant.

[0078] At this time, if Figure 4 As shown by the solid line A in (A), the temperature of the electronic component 27 drops significantly from the time T1 to the time T4 compared to the outside air temperature (for example, less than -40°C), and gradually rises after the time T4. Thus, the reason why the temperature of the electronic component 27 drops significantly from the time T1 to the time T4 compared to the outside air temperature is that the electronic component 27 is cooled by the refrigerant through heat exchange between the electronic component 27 and the refrigerant. At this time, if the temperature of the electronic component 27 is lower than the allowable temperature on the low temperature side (for example, -40°C), there is a concern that the electronic component 27 may malfunction. In addition, the reason why the temperature of the electronic component 27 gradually rises after the time T4 is that the electronic component 27 generates heat itself due to power-on.

[0079] on the other hand, Figure 5 1 shows an electric compressor 1 according to a first embodiment. Figure 5 As shown in (A), the period from time T10 to time T11 is the state before the electric compressor 1 is started, and the temperature of the electronic component 27 shown by the solid line D, the temperature of the refrigerant shown by the single-point chain line F, and the temperature of the cooling water shown by the dotted line E are the same as the outdoor air temperature (for example, -35°C). Figure 5 As shown by the solid line G in (B), the electric compressor 1 starts at time T11 (i.e., the refrigeration cycle starts at time T11), and operates at a constant speed after time T12. At this time, in the electric compressor 1 of the first embodiment, as in the comparative example, Figure 5 As indicated by the dashed line F in (A), the refrigerant temperature drops significantly (eg, about -50°C) from the outside air temperature from time T11 to time T13, and changes to a substantially constant temperature after time T13.

[0080] At this time, if Figure 5 As shown by the dotted line E in (A), the temperature of the cooling water gradually rises from the outside air temperature after time T11. This is because the high-temperature and high-pressure refrigerant output by the compression operation of the electric compressor 1 heats the cooling water flowing in the first cooling water circuit 4 via the high-temperature side refrigerant-cooling water heat exchanger 7, so that the temperature of the cooling water gradually rises.

[0081] Moreover, if Figure 5 As shown by the solid line D in (A), the temperature of the electronic component 27 gradually rises after the time T11. This is because the electric compressor 1 of the first embodiment suppresses the electronic component 27 from being cooled by the refrigerant by the cooling water flowing in the cooling water flow path 20 and the electronic component 27, and further, the temperature of the electronic component 27 rises by the self-heating of the electronic component 27 due to the power supply. Therefore, in the structure of the first embodiment, even if the refrigerant temperature drops significantly below the outside air temperature just after the refrigeration cycle is started in an extremely low temperature environment, the cooling water flowing in the cooling water flow path 20 and the electronic component 27 exchange heat, thereby preventing the temperature of the electronic component 27 from becoming less than the allowable temperature on the low temperature side.

[0082] <Regarding the temperature of the winding 32 (hereinafter referred to as “winding temperature”)>

[0083] then, Figure 6 and Figure 7 This is a graph showing the relationship between the winding temperature of the electric motor 11 and the refrigerant temperature when the operating conditions of the electric compressor 1 included in the refrigeration cycle device 3 are low-speed rotation operation and high load.

[0084] Figure 6 (A) Figure 7 The solid lines H and K in (A) represent the winding temperature of the motor 11. Figure 6 (A) Figure 7 The dashed lines I and M in (A) represent the temperature of the refrigerant flowing in the refrigerant flow path 25 of the electric compressor. Figure 7 A broken line L in (A) indicates the temperature of the cooling water flowing through the cooling water flow path 20 of the electric compressor 1 according to the first embodiment.

[0085] and, Figure 6 (B) Figure 7 Solid lines J and O in (B) represent the cooling capacity of the refrigerant flowing through the refrigerant flow path 25 . Figure 7 The two-dot chain line N in (B) represents the cooling capacity of the cooling water flowing in the cooling water flow path 20 .

[0086] Figure 6 denoted as a comparative example of an electric compressor. Figure 6 As shown in (A), the period from time T20 to T21 is the state before the electric compressor of the comparative example is started, and the winding temperature shown by the solid line H and the refrigerant temperature shown by the one-dot chain line I are about the same as the outdoor air temperature.

[0087] The electric compressor starts at time T21 (i.e., the refrigeration cycle starts at time T21), and operates at a constant low speed after time T22. Figure 6 As shown by the dashed line I in (A), the refrigerant temperature drops significantly from the outside air temperature from time T21 to time T23, and then remains at a substantially constant temperature after time T23. Figure 6 As shown by the solid line J in (B), the cooling capacity of the refrigerant flowing in the refrigerant flow path 25 gradually increases from time T21 and becomes a constant capacity after time T22. However, the operating condition of the electric compressor 1 is low-speed rotation operation, and the refrigerant flow rate is small, so the cooling capacity of the refrigerant flowing in the refrigerant flow path 25 is small.

[0088] At this time, if Figure 6As shown by the solid line H in (A), the winding temperature gradually rises after time T21 due to the self-heating of the winding 32 caused by the power supply. At this time, since the operating condition of the electric compressor is high load, the amount of current flowing to the winding 32 is large, and the self-heating of the winding 32 is also large. However, since the cooling capacity of the refrigerant flowing in the refrigerant flow path 25 is small as mentioned above, there is a concern that the winding temperature exceeds its own protection temperature (for example, about 140°C). In this case, in order to prevent the winding temperature from exceeding the protection temperature, the electric compressor of the comparative example must take measures such as changing the operating point of the electric compressor 1, or temporarily stopping or intermittently operating the electric compressor 1.

[0089] on the other hand, Figure 7 1 shows the electric compressor 1 of the first embodiment. In the first embodiment, the first cooling water circuit 4 is operated from before time T31 (that is, before the electric compressor 1 is started). Figure 7 As shown in (A), the period from time T30 to T31 is the state before the electric compressor 1 is started, and the winding temperature shown by the solid line K and the refrigerant temperature shown by the dashed line M are at the same level as the cooling water temperature shown by the dotted line L.

[0090] The electric compressor 1 starts at time T31 (i.e., the refrigeration cycle starts at time T31), and operates at a constant rotation speed after time T32. Figure 7 As shown by the dashed line M in (A), the refrigerant temperature drops below the outside air temperature from time T31 to time T33, and then remains at a substantially constant temperature after time T33. Figure 7 As shown by the solid line O in (B), the cooling capacity of the refrigerant flowing in the refrigerant flow path 25 gradually increases from time T31 and becomes a constant capacity after time T32. However, in the first embodiment, since the operating condition of the electric compressor 1 is also low-speed rotation operation, the cold refrigerant flow rate is small, and thus the cooling capacity of the refrigerant flowing in the refrigerant flow path 25 is also small.

[0091] On the other hand, Figure 7 As shown by the double dotted line N in (B), in the first embodiment, since the amount of cooling water flowing in the first cooling water circuit 4 is relatively large, the cooling capacity of the cooling water flowing in the cooling water flow path 20 is greater than the cooling capacity of the refrigerant flowing in the refrigerant flow path 25.

[0092] At this time, if Figure 7As shown by the solid line K in (A), the winding temperature gradually rises after the time T31. In the first embodiment, the operating condition of the electric compressor 1 is also high load, so the amount of current flowing to the winding 32 is large, and the self-heating of the winding 32 is also large. On the other hand, since the operating condition of the electric compressor 1 is low-speed rotation operation, the refrigerant flow rate is small, and thus the cooling capacity of the refrigerant flowing in the refrigerant flow path 25 is small. However, in the first embodiment, since the cooling water flowing in the cooling water flow path 20, the winding 32, and the refrigerant flowing in the refrigerant flow path 25 perform heat exchange, the winding 32 is fully cooled by the cooling water, thereby preventing the winding 32 from exceeding its own protection temperature. Therefore, in the first embodiment, the limitation of the operating area can be suppressed, and the limitation of the operating area is used for winding protection caused by insufficient refrigerant cooling of the winding 32 when the electric compressor 1 rotates at a low speed and has a high load.

[0093] Here, refer to Figure 8 The operating range of the electric compressor 1 will be described.

[0094] The operating area of ​​the electric compressor 1 is a range of possible operation expressed by the rotation speed and torque of the motor 11, or the rotation speed and motor current (i.e., the current supplied to the motor 11). Figure 8 In FIG. 1 , the horizontal axis represents the rotation speed, and the vertical axis represents the torque or the motor current. P on the horizontal axis represents the lowest rotation speed of the motor 11 when the motor 11 is stable. Q on the vertical axis represents the maximum torque or the maximum motor current. Therefore, the electric compressor 1 operates in an operating range of more than P and less than Q.

[0095] The cooling performance of the refrigerant in the refrigerant flow path 25 increases as the rotation speed of the electric compressor 1 increases, and the cooling performance of the refrigerant in the refrigerant flow path 25 decreases as the rotation speed of the electric compressor 1 decreases. The electric compressor of the comparative example is a structure in which no cooling water flow path 20 is provided in the casing 19, and the electric motor 11 is cooled only by the refrigerant in the refrigerant flow path 25. For this reason, in the case of the electric compressor of the comparative example, in an operating area where the rotation speed of the electric motor 11 is low, that is, in an area where the cooling performance of the refrigerant in the refrigerant flow path 25 is low, when the torque or the motor current is large, a problem occurs that the winding temperature of the electric motor 11 exceeds the protection temperature. As a result, a limitation of the operating area is generated, and the limitation of the operating area means that the cooling performance cannot be utilized in the Figure 8 The upper left portion of the range indicated by hatching (hereinafter referred to as "operating region R"). Therefore, as the performance of the refrigeration cycle, although it is sufficient to be able to operate in the operating region R, when it is not possible to operate in the operating region R, it is necessary to increase the rotation speed and perform intermittent operation.

[0096] In contrast, the electric compressor 1 of the first embodiment is configured to cool the electric motor 11 through both the refrigerant flow path 25 and the cooling water flow path 20 provided in the housing 19. Thus, in contrast to the problem of insufficient cooling of the electric motor 11 during low-speed rotation caused by cooling by only the refrigerant, as in the electric compressor of the comparative example, the electric compressor of the first embodiment can maintain the winding temperature of the electric motor 11 and expand the operating range by cooling through the cooling water flow path 20.

[0097] <Control processing performed by ECU 6>

[0098] Next, refer to Fig. 9 and Fig.10 The flowchart of FIG. 1 illustrates a control process executed by the ECU 6 included in the thermal management system 2 .

[0099] Fig. 9 This is a diagram showing an example of a control process executed by the ECU 6 when the thermal management system 2 is activated.

[0100] First, in step S100 , the ECU 6 activates the first coolant circuit 4 . Specifically, the ECU 6 activates the first coolant pump 17 provided in the first coolant circuit 4 .

[0101] Next, in step S101, the ECU 6 activates the refrigeration cycle device 3. Specifically, the ECU 6 activates the electric compressor 1 of the refrigeration cycle device 3 after a predetermined time has elapsed since the first cooling water pump 17 was activated.

[0102] Thus, the cooling water flowing in the cooling water flow path 20 can perform heat exchange with the electronic components 27 and the winding 32 before the operation of the refrigeration cycle device 3 starts. In addition, the specified time of step S101 is the time during which the cooling water flowing in the cooling water flow path 20 can perform heat exchange with the electronic components 27 and the winding 32, which is set through experiments, etc. and stored in the ECU 6.

[0103] on the other hand, Fig.10 1 is a diagram showing an example of a control process executed by the ECU 6 when the heat management system 2 is stopped.

[0104] First, in step S200 , the ECU 6 stops the refrigeration cycle device 3 . Specifically, the ECU 6 stops the electric compressor 1 of the refrigeration cycle device 3 .

[0105] Next, in step S201, the ECU 6 stops the first coolant circuit 4. Specifically, after a predetermined time has elapsed since the electric compressor 1 was stopped, the ECU 6 stops the first coolant pump 17 provided in the first coolant circuit 4.

[0106] Thus, even after the operation of the refrigeration cycle device 3 is stopped, the cooling water flowing in the cooling water flow path 20 can exchange heat with the electronic components 27 and the winding 32. In addition, the specified time of step S201 is also the time during which the cooling water flowing in the cooling water flow path 20 can exchange heat with the electronic components 27 and the winding 32, which is set through experiments and the like and stored in the ECU 6.

[0107] The electric compressor 1 and the heat management system 2 according to the first embodiment described above provide the following operational effects.

[0108] (1) The electric compressor 1 of the first embodiment includes a refrigerant flow path 25 and a cooling water flow path 20 inside the housing 19. The refrigerant flow path 25 is provided so that the low-temperature and low-pressure refrigerant before being sucked into the refrigerant compression unit 12 can exchange heat with the winding 32 and the electronic components 27. The cooling water flow path 20 is provided so that the cooling water flowing in the cooling water flow path 20 can exchange heat with the winding 32 and the electronic components 27.

[0109] Based on this, the winding 32 and the electronic component 27 can exchange heat with the refrigerant flowing in the refrigerant flow path 25, and can also exchange heat with the cooling water flowing in the cooling water flow path 20. Therefore, when the refrigeration cycle device 3 is used for heating when the outside air is extremely low temperature, even if the refrigerant temperature is lower than the low temperature side allowable temperature of the electronic component 27, the heat exchange between the cooling water and the electronic component 27 can prevent the temperature of the electronic component 27 from being lower than the low temperature side allowable temperature.

[0110] Moreover, when the electric compressor 1 is rotating at a low speed and under a high load in the operating conditions of the refrigeration cycle device 3, the refrigerant flow rate is reduced, and the cooling capacity of the refrigerant relative to the winding 32 is reduced. At this time, the temperature of the winding 32 can be prevented from being higher than its own protection temperature by heat exchange between the cooling water and the winding 32. For this reason, the control of changing the operating point of the electric compressor 1 can be suppressed in a manner that the temperature of the winding 32 does not exceed its own protection temperature, or the control of temporarily stopping or intermittently operating the electric compressor 1 can be suppressed. Therefore, the situation where the operating area of ​​the electric compressor 1 is limited can be suppressed.

[0111] Furthermore, generally, the temperature difference between the low temperature and high temperature of the cooling water flowing in the cooling water flow path 20 is smaller than the temperature difference between the low temperature and high temperature of the refrigerant flowing in the refrigerant flow path 25. For this reason, by forming a structure in which the cooling water flowing in the cooling water flow path 20 and the electronic component 27 perform heat exchange, the temperature change of the electronic component 27 can be suppressed. Therefore, the life of the electronic component 27 can be extended.

[0112] (2) In the first embodiment, the refrigerant flow path 25 is configured so that the refrigerant flows at least between the stator 28 and the rotor 29 of the motor 11. Therefore, the refrigerant flowing in the refrigerant flow path 25 can directly exchange heat with the motor 11, and the refrigerant flowing in the refrigerant flow path 25 can exchange heat with the electronic components 27 through the housing 19.

[0113] The cooling water flow path 20 is configured to allow cooling water to flow to a hole formed in the housing 19 between the motor 11 and the electric control unit 26. Therefore, the cooling water flowing in the cooling water flow path 20 can exchange heat with the motor 11 and the electronic components 27 through the housing 19.

[0114] Based on this, the winding 32 and the electronic components 27 can exchange heat with the refrigerant flowing in the refrigerant flow path 25 , and can also exchange heat with the cooling water flowing in the cooling water flow path 20 .

[0115] (3) In the first embodiment, the electronic components 27 (eg, the filter 57 , the switching element 58 , etc.) that generate heat when energized are arranged closer to the cooling water flow path 20 than the center position CP of the electric control unit 26 .

[0116] Based on this, in the structure of the electric control unit 26, the heat exchange efficiency between the electronic component 27 that generates heat by powering on and the cooling water can be made higher than the heat exchange efficiency between the other components in the electric control unit 26 and the cooling water. In addition, the temperature change of the electronic component 27 can be suppressed, and the life of the electronic component 27 can be extended.

[0117] (4) In the thermal management system 2 of the first embodiment, the cooling water flow path 20 provided in the electric compressor 1 is a flow path through which cooling water flows from the high temperature side cooling water-air heat exchanger 16 to the high temperature side refrigerant-cooling water heat exchanger 7 .

[0118] Based on this, the cooling water flowing from the high-temperature side cooling water-air heat exchanger 16 to the high-temperature side refrigerant-cooling water heat exchanger 7 is the cooling water before the high-temperature side cooling water-air heat exchanger 16 dissipates heat to the air and absorbs heat from the refrigerant in the high-temperature side refrigerant-cooling water heat exchanger 7. For this reason, compared with the use of cooling water on the downstream side of the high-temperature side refrigerant-cooling water heat exchanger 7, by using cooling water on the upstream side of the high-temperature side refrigerant-cooling water heat exchanger 7, the cooling efficiency of the winding 32 by the cooling water can be improved, and the amount of heat absorbed by the cooling water from the winding 32 can be increased. Therefore, the winding 32 can be cooled, and the efficiency of the thermal management system 2 can be improved by making the temperature of the cooling water circulating in the cooling water circuit higher.

[0119] (5) The ECU 6 included in the thermal management system 2 of the first embodiment is configured to execute control to activate the first cooling water pump 17 a predetermined time before the electric compressor 1 is activated. Furthermore, the ECU 6 is configured to execute control to stop the first cooling water pump 17 after a predetermined time has passed since the electric compressor 1 was stopped.

[0120] Therefore, by operating the first cooling water pump 17 a predetermined time before operating the electric compressor 1 , the cooling water flowing in the cooling water flow path 20 can exchange heat with the electronic components 27 and the winding 32 before the operation of the refrigeration cycle device 3 starts.

[0121] Furthermore, by stopping the first cooling water pump 17 after a predetermined time has passed since the electric compressor 1 was stopped, the cooling water flowing in the cooling water flow path 20 can exchange heat with the winding 32 and the electronic components 27 even after the operation of the refrigeration cycle device 3 is stopped or temporarily stopped.

[0122] Therefore, when the refrigeration cycle device 3 is used for heating when the outside air is extremely low, even if the refrigerant temperature is lower than the allowable temperature on the low temperature side of the electronic component 27, heat exchange between the cooling water and the electronic component 27 can prevent the temperature of the electronic component 27 from being lower than the allowable temperature on the low temperature side.

[0123] Furthermore, even after the operation of the refrigeration cycle device 3 is stopped or temporarily stopped, the winding 32 and the electronic components 27 can be cooled by heat exchange between the cooling water and the winding 32 and the electronic components 27. Therefore, it is possible to suppress the operating range of the electric compressor 1 from being limited.

[0124] (Second Embodiment)

[0125] The second embodiment will be described. The second embodiment will describe an example of a control process executed by the ECU 6 included in the thermal management system 2. Since the rest is the same as the first embodiment, only the parts different from the first embodiment will be described.

[0126] Reference Fig.11 The control process executed by the ECU 6 included in the thermal management system 2 of the second embodiment will be described with reference to the flowchart of FIG. This process is repeatedly executed during the operation of the thermal management system 2.

[0127] exist Fig.11 In step S300, the ECU 6 determines whether the rotation speed of the electric compressor 1 of the refrigeration cycle device 3 is equal to or less than a predetermined rotation speed threshold. If the rotation speed of the electric compressor 1 is equal to or less than the predetermined rotation speed threshold, the process proceeds to step S301.

[0128] In step S301, ECU 6 determines whether the load of electric compressor 1 of refrigeration cycle device 3 is equal to or greater than a predetermined load threshold. If the load of electric compressor 1 is equal to or greater than the predetermined load threshold, the process proceeds to step S302.

[0129] In step S302 , the ECU 6 executes control to increase the flow rate of the coolant flowing in the first coolant circuit 4 , such as increasing the rotation speed of the first coolant pump 17 in the first coolant circuit 4 .

[0130] On the other hand, if the rotation speed of the electric compressor 1 is greater than the predetermined rotation speed threshold in the above step S300, the process proceeds to step S303. Also, if the load of the electric compressor 1 is less than the predetermined load threshold in the step S301, the process proceeds to step S303.

[0131] In step S303 , the ECU 6 sets the rotation speed of the first coolant pump 17 of the first coolant circuit 4 to a normal value, thereby setting the flow rate of the coolant flowing in the first coolant circuit 4 to a normal flow rate.

[0132] In the second embodiment described above, when the electric compressor 1 operates at a speed lower than a predetermined rotational speed threshold and at a load higher than a predetermined load threshold, the ECU 6 included in the thermal management system 2 controls the flow rate of the coolant flowing through the first coolant circuit 4 to increase.

[0133] Based on this, under the condition of low speed rotation and high load, which is a heat resistance problem of the electric compressor 1, the cooling capacity of the first cooling water circuit 4 is increased, thereby further improving the cooling effect of the cooling water flowing in the cooling water flow path 20 provided in the electric compressor 1.

[0134] (Variation 1 of the Second Embodiment)

[0135] In the above description of the second embodiment, the ECU 6 determines in step S301 whether the load of the electric compressor 1 of the refrigeration cycle device 3 is equal to or greater than a predetermined load threshold, but the present invention is not limited thereto.

[0136] For example, instead of the process of step S301, the ECU 6 may determine whether the pressure of the refrigerant discharged from the electric compressor 1 is above a predetermined pressure threshold. And, if the refrigerant pressure is above the predetermined pressure threshold, the ECU 6 advances the process to step S302. On the other hand, if the refrigerant pressure is less than the predetermined pressure threshold, the process advances to step S303. In this way, the same effects as those of the second embodiment can be achieved.

[0137] (Variation 2 of the Second Embodiment)

[0138] Moreover, for example, instead of the process of step S301, the ECU 6 may determine whether the current supplied to the motor 11 is equal to or greater than a predetermined current threshold. Furthermore, when the ECU 6 determines that the current supplied to the motor 11 is equal to or greater than the predetermined current threshold, the process proceeds to step S302. On the other hand, when the current supplied to the motor 11 is less than the predetermined current threshold, the process proceeds to step S303. In this way, the same effects as those of the second embodiment can be achieved.

[0139] (Third Embodiment)

[0140] The third embodiment will also describe an example of a control process executed by the ECU 6 included in the thermal management system 2 , and since the rest is the same as the first embodiment, only the parts different from the first embodiment will be described.

[0141] In the third embodiment, the ECU 6 may mediate between the refrigeration cycle device 3 and the first coolant circuit 4 to control the electric motor 11 and the electronic components 27 of the electric control unit 26 to be appropriately cooled.

[0142] When the outside air is extremely low temperature, for example, the control of the refrigeration cycle device 3 is adjusted so that the temperature of the refrigerant flowing out of the low temperature side refrigerant-cooling water heat exchanger 9 and sucked into the refrigerant compression part 12 of the electric compressor 1 becomes high. Moreover, for example, it is adjusted so that the temperature of the cooling water flowing in the cooling water flow path 20 becomes a predetermined temperature or higher before the refrigeration cycle device 3 is operated. Through these controls, when the outside air is extremely low temperature, the electric control unit 26 and the electric motor 11 can be controlled so that they become appropriate temperatures.

[0143] On the other hand, under the condition that the protection temperature of the winding 32 of the electric motor 11 becomes a problem at low speed rotation and high load, for example, the control of the refrigeration cycle device 3 is adjusted in such a way that the temperature of the refrigerant flowing out of the low-temperature side refrigerant-cooling water heat exchanger 9 and sucked into the refrigerant compression part 12 of the electric compressor 1 is reduced. Moreover, for example, the control of the refrigeration cycle device 3 is adjusted in such a way that the cooling performance of the refrigerant to the electric motor 11 is improved by only slightly increasing the rotation speed of the electric compressor 1. Moreover, for example, the control of the first cooling water circuit 4 is adjusted in such a way that the heat dissipation capacity of the high-temperature side cooling water-air heat exchanger 16 of the first cooling water circuit 4 to the cooling water is increased, so that the temperature of the cooling water flowing in the cooling water flow path 20 is reduced and the cooling performance of the cooling water to the electric motor 11 is improved. Moreover, for example, the control of the first cooling water circuit 4 is adjusted in such a way that the flow rate of the cooling water flowing in the cooling water flow path 20 is increased and the cooling performance of the cooling water to the electric motor 11 is improved. Through these controls, when the protection temperature of the winding 32 becomes a problem at low speed rotation and high load, the electric motor 11 and the electrical control unit 26 can be controlled to be at appropriate temperatures.

[0144] (Other Embodiments)

[0145] (1) In the above-mentioned embodiments, the electric compressor 1 is provided with the housing 19, the refrigerant flow path 25, the cooling water flow path 20, the motor 11, the refrigerant compression unit 12, the electric control unit 26, etc., but the present invention is not limited thereto. For example, in addition to the above-mentioned structure, the electric compressor 1 may be formed by integrating various parts of the refrigeration cycle device such as the accumulator and the oil separator.

[0146] (2) In the above-mentioned embodiments, the ECU 6 controls the driving of the electric compressor 1, the first cooling water pump 17, and the second cooling water pump 23 of the thermal management system 2, but the present invention is not limited thereto. For example, the driving of the electric compressor 1, the first cooling water pump 17, and the second cooling water pump 23 may be controlled by the electrical control unit 26 of the electric compressor 1, or by an electronic control device different therefrom.

[0147] The present disclosure is not limited to the above-mentioned embodiments and can be appropriately changed. Moreover, the above-mentioned embodiments and a part thereof are not unrelated to each other, and can be appropriately combined except for the case where it is obviously impossible to combine. Moreover, in the above-mentioned embodiments, the elements constituting the embodiments are of course not necessary, except for the case where it is clearly indicated that it is particularly necessary and the case where it is obviously necessary in principle. Moreover, in the above-mentioned embodiments, when referring to the numerical values ​​of the number, value, amount, range, etc. of the structural elements of the embodiments, except for the case where it is clearly indicated that it is necessary and the case where it is obviously limited to a specific number in principle, it is not limited to the specific number. Moreover, in the above-mentioned embodiments, when referring to the shape, positional relationship, etc. of the constituent elements, etc., except for the case where it is particularly clearly indicated and the case where it is limited to a specific shape, positional relationship, etc. in principle, it is not limited to the shape, positional relationship, etc.

[0148] The control unit and its methods described in the present disclosure may also be implemented by a special-purpose computer, which is provided by a processor and a memory programmed in a manner to execute one or more functions concretized by a computer program. Alternatively, the control unit and its methods described in the present disclosure may also be implemented by a special-purpose computer, which is provided by a processor composed of one or more special-purpose hardware logic circuits. Alternatively, the control unit and its methods described in the present disclosure may also be implemented by one or more special-purpose computers, which are composed of a combination of a processor and a memory programmed in a manner to execute one or more functions and a processor composed of one or more hardware logic circuits. Moreover, the computer program, as an instruction executed by a computer, may also be stored in a computer-readable non-transient tangible recording medium.

[0149] (Viewpoints of this publication)

[0150] The present disclosure described above can be understood as, for example, the following viewpoints.

[0151] [First point of view]

[0152] An electric compressor, used in a refrigeration cycle device (3), characterized by comprising:

[0153] a casing (19), the casing constituting the outer shell;

[0154] An electric motor (11) is arranged inside the housing and is driven to rotate by supplying electricity to the winding (32);

[0155] a refrigerant compression unit (12) which sucks in, compresses and discharges refrigerant through the drive of the electric motor;

[0156] An electrical control unit (26) having an electronic component (27) that generates heat when energized, and controls energization of the winding of the motor;

[0157] a refrigerant flow path (25), the refrigerant flow path being arranged inside the casing, the refrigerant flow path being arranged so that the low-temperature and low-pressure refrigerant before being sucked into the refrigerant compression part can exchange heat with the motor and the electrical control part;

[0158] and a cooling water flow path (20) provided inside the housing, the cooling water flow path being configured so that cooling water flowing in the cooling water flow path can perform heat exchange with the motor and the electrical control unit.

[0159] [Second point of view]

[0160] In the electric compressor according to the first aspect,

[0161] The refrigerant flow path is configured so that the refrigerant flows at least between a stator (28) and a rotor (29) of the motor, the refrigerant in the refrigerant flow path can directly exchange heat with the motor, and the refrigerant in the refrigerant flow path can exchange heat with the electrical control unit via the casing.

[0162] The cooling water flow path is configured to allow cooling water to flow through a hole formed in the casing at a location between the electric motor and the electric control unit, and the cooling water in the cooling water flow path can exchange heat with the electric motor and the electric control unit via the casing.

[0163] [Third point of view]

[0164] In the electric compressor according to the first or second aspect,

[0165] The electronic component that generates heat when energized is disposed at a position closer to the cooling water flow path than a center position (CP) of the electric control unit.

[0166] [Fourth Viewpoint]

[0167] A thermal management system comprising:

[0168] A refrigeration cycle device, the refrigeration cycle device being configured to connect the electric compressor described in the first aspect, a high-temperature side refrigerant-cooling water heat exchanger (7) for performing heat exchange between the refrigerant discharged from the refrigerant compression section of the electric compressor and cooling water, an expansion valve (8) for decompressing and expanding the refrigerant flowing out of the high-temperature side refrigerant-cooling water heat exchanger, and a low-temperature side refrigerant-heat medium heat exchanger (9) for performing heat exchange between the refrigerant flowing out of the expansion valve and a heat medium through a refrigerant piping so as to circulate the refrigerant; and

[0169] A cooling water circuit (4) is provided, wherein the high-temperature side cooling water-air heat exchanger (16) for heat exchange between air and cooling water, the high-temperature side refrigerant-cooling water heat exchanger, and a cooling water pump (17) are connected through cooling water piping to circulate cooling water, wherein:

[0170] The cooling water flow path included in the electric compressor is a flow path through which cooling water flows from the high-temperature-side cooling water-air heat exchanger to the high-temperature-side refrigerant-cooling water heat exchanger.

[0171] [Fifth Viewpoint]

[0172] A thermal management system according to a fourth aspect, wherein:

[0173] The thermal management system further comprises an electronic control device (6) for controlling the operation of the cooling water pump and the electric compressor.

[0174] The electronic control device is configured as follows:

[0175] The control for operating the cooling water pump is performed a predetermined time before the electric compressor is operated,

[0176] The control for stopping the cooling water pump is performed after a predetermined time has elapsed since the electric compressor was stopped.

Claims

1. An electric compressor used in a refrigeration cycle device (3), characterized in that: have: a casing (19), the casing constituting the outer shell; An electric motor (11) is arranged inside the housing and is driven to rotate by supplying electricity to the winding (32); a refrigerant compression unit (12) which sucks in, compresses and discharges refrigerant through the drive of the electric motor; An electrical control unit (26) having an electronic component (27) that generates heat when energized, and controls energization of the winding of the motor; a refrigerant flow path (25), the refrigerant flow path being arranged inside the casing, the refrigerant flow path being arranged so that the low-temperature and low-pressure refrigerant before being sucked into the refrigerant compression part can exchange heat with the motor and the electrical control part; as well as A cooling water flow path (20) is provided inside the housing, and the cooling water flow path is configured so that cooling water flowing in the cooling water flow path can exchange heat with the motor and the electrical control unit.

2. The electric compressor according to claim 1, characterized in that: The refrigerant flow path is configured so that the refrigerant flows at least between a stator (28) and a rotor (29) of the motor, the refrigerant in the refrigerant flow path can directly exchange heat with the motor, and the refrigerant in the refrigerant flow path can exchange heat with the electrical control unit via the casing. The cooling water flow path is configured to allow cooling water to flow through a hole formed in the casing at a location between the electric motor and the electric control unit, and the cooling water in the cooling water flow path can exchange heat with the electric motor and the electric control unit via the casing.

3. The electric compressor according to claim 1 or 2, characterized in that: The electronic component that generates heat when energized is disposed at a position closer to the cooling water flow path than a center position (CP) of the electric control unit.

4. A thermal management system, characterized in that: have: A refrigeration cycle device, the refrigeration cycle device being configured to connect the electric compressor according to claim 1, a high-temperature side refrigerant-cooling water heat exchanger (7) for performing heat exchange between the refrigerant discharged from the refrigerant compression section of the electric compressor and cooling water, an expansion valve (8) for decompressing and expanding the refrigerant flowing out of the high-temperature side refrigerant-cooling water heat exchanger, and a low-temperature side refrigerant-heat medium heat exchanger (9) for performing heat exchange between the refrigerant flowing out of the expansion valve and a heat medium through a refrigerant piping (10) so as to circulate the refrigerant; and A cooling water circuit (4) is provided, wherein the cooling water circuit connects a high-temperature side cooling water-air heat exchanger (16) for performing heat exchange between air and cooling water, the high-temperature side refrigerant-cooling water heat exchanger, and a cooling water pump (17) through a cooling water pipe (18) to circulate cooling water. The cooling water flow path included in the electric compressor is a flow path through which cooling water flows from the high-temperature-side cooling water-air heat exchanger to the high-temperature-side refrigerant-cooling water heat exchanger.

5. The thermal management system according to claim 4, characterized in that: The thermal management system further comprises an electronic control device (6) for controlling the operation of the cooling water pump and the electric compressor. The electronic control device is configured as follows: The control for operating the cooling water pump is performed a predetermined time before the electric compressor is operated, The control for stopping the cooling water pump is performed after a predetermined time has elapsed since the electric compressor was stopped.

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