Electric vehicle thermal management system

Abstract

The application provides an electric vehicle thermal management system in the field of electric vehicle thermal management, which relates to a refrigerant circuit, a coolant circuit and a battery circuit, wherein the coolant circuit is connected with the refrigerant circuit and the battery circuit respectively, and the refrigerant circuit is connected with the battery circuit; the refrigerant circuit comprises a high-pressure cooling circuit, a first throttling mechanism, a first heat exchange device, a second throttling mechanism and an evaporator, one end of the high-pressure cooling circuit is connected with the first heat exchange device and the evaporator respectively, the other end of the high-pressure cooling circuit is connected with the first throttling mechanism and the second throttling mechanism respectively, the first throttling mechanism is connected with the first heat exchange device, and the second throttling mechanism is connected with the evaporator. The application uses a heat pump to heat the battery, is more energy-saving, fully utilizes waste heat or heat dissipation, further improves the energy efficiency of the thermal management system, the structure of the refrigerant circuit is very simple, the reliability is high, and the refrigerant circuit is easy to control; the structure of the coolant circuit is flexible, and different working modes can be conveniently configured to make the system energy efficiency at the optimal level.

Description

Technical Field

[0001] This invention relates to the field of thermal management of electric vehicles, and more specifically, to a thermal management system for electric vehicles. Background Technology

[0002] Compared to traditional gasoline vehicles, all the heat in electric vehicles comes from the output of the battery. Therefore, how to make full and reasonable use of the waste heat generated by various components during vehicle operation and the heat from the external environment, thereby improving the energy efficiency of the battery, is of great significance for the thermal management of electric vehicles.

[0003] Heat pump air conditioning technology effectively utilizes ambient heat, resulting in an energy efficiency 2-3 times higher than traditional electric heating methods, making it highly suitable for electric vehicle thermal management. However, existing heat pump air conditioning systems primarily use heat pump technology to heat the passenger compartment, while battery heating in winter generally still relies on electric heating. Furthermore, current electric vehicle thermal management systems typically struggle to fully utilize the waste heat generated by the motor and electronic control system during operation, failing to achieve optimal energy utilization.

[0004] A search of existing patent literature revealed Chinese invention patent publication number CN111645511A, which discloses an electric vehicle thermal management system and an electric vehicle, belonging to the automotive field. This system improves the energy utilization efficiency of the electric vehicle thermal management system and reduces its manufacturing cost, thereby lowering the overall manufacturing cost of the electric vehicle. It includes an electric drive temperature control system, a battery temperature control system, and an air conditioning system. All three systems are communicatively connected to the vehicle's controller, which controls their operating states. This design utilizes the vehicle controller to simultaneously control all three systems, unlike the previous method of using separate controllers for each system. Summary of the Invention

[0005] In view of the deficiencies in the prior art, the purpose of this invention is to provide a thermal management system for electric vehicles.

[0006] According to the present invention, an electric vehicle thermal management system includes a refrigerant circuit, a coolant circuit, and a battery circuit, wherein the coolant circuit is connected to the refrigerant circuit and the battery circuit, and the refrigerant circuit is connected to the battery circuit. The refrigerant circuit includes a high-pressure cooling circuit, a first throttling mechanism, a first heat exchange device, a second throttling mechanism, and an evaporator. One end of the high-pressure cooling circuit is connected to the first heat exchange device and the evaporator, respectively, and the other end of the high-pressure cooling circuit is connected to the first throttling mechanism and the second throttling mechanism, respectively. The first throttling mechanism is connected to the first heat exchange device, and the second throttling mechanism is connected to the evaporator. The refrigerant in the high-pressure cooling circuit flows into the first throttling mechanism and / or the second throttling mechanism. After being depressurized by the first throttling mechanism, the refrigerant flows into the first heat exchanger, where it absorbs heat from the coolant circuit. Alternatively, the refrigerant after being depressurized by the second throttling mechanism flows into the evaporator, where it absorbs heat from the passenger compartment. The refrigerant that has absorbed heat from the first heat exchanger and / or the evaporator then flows back into the high-pressure cooling circuit for refrigerant circulation.

[0007] In some embodiments, the high-pressure cooling circuit includes a gas-liquid separator, a compressor, and a water-cooled condenser. One end of the gas-liquid separator is connected to a first heat exchange device and an evaporator, respectively. The other end of the gas-liquid separator is connected to the compressor, and the compressor is connected to one end of the water-cooled condenser. The other end of the water-cooled condenser is connected to a first throttling mechanism and a second throttling mechanism, respectively.

[0008] In some embodiments, the high-pressure cooling circuit includes a compressor, a water-cooled condenser, and a liquid storage tank. One end of the compressor is connected to a first heat exchange device and an evaporator, and the other end of the compressor is connected to the water-cooled condenser. The water-cooled condenser is connected to one end of the liquid storage tank, and the other end of the liquid storage tank is connected to a first throttling mechanism and a second throttling mechanism.

[0009] In some embodiments, the battery circuit includes a drive battery, a second heat exchange device, a first water valve, a third water valve, and a first water pump. One end of the drive battery is connected to the second heat exchange device, and the other end of the drive battery is connected to the first water pump. The first water pump is connected to the third water valve, the third water valve is connected to the first water valve, the first water valve is connected to the second heat exchange device, the first water valve is connected to both the refrigerant circuit and the coolant circuit, and the third water valve is connected to the coolant circuit.

[0010] In some embodiments, the coolant circuit includes a drive motor, a motor control unit, a second water pump, a fourth water valve, a heater core, a sixth water valve, a third water pump, an electric heater, a second water valve, a fifth water valve, and a third heat exchange device. The motor control unit is connected to the drive motor, the drive motor is connected to the fifth water valve, the third heat exchange device is connected to both the drive motor and the fifth water valve, the fifth water valve is connected to the third water valve, the third water valve is connected to the second water valve, the second water valve is connected to the fourth water valve, the fourth water valve is connected to a water-cooled condenser, the water-cooled condenser is connected to the electric heater, the electric heater is connected to the third water pump, the third water pump is connected to the sixth water valve, the sixth water valve is connected to the heater core, the heater core is connected to the fourth water valve, the fourth water valve is connected to the second water pump, and the second water pump is connected to the motor control unit.

[0011] In some embodiments, the motor control unit is connected to the refrigerant circuit, the coolant circuit, and the battery circuit.

[0012] In some embodiments, the first water valve, the second water valve, the third water valve, and the fourth water valve are four-way water valves; The first water valve is connected to the first heat exchanger, the second heat exchanger, the third water valve, and the second water valve respectively; The second water valve is connected to the first water valve, the third water valve, the fourth water valve, and the first heat exchange device. The third water valve is connected to the first water valve, the first water pump, the fifth water valve, and the second water valve respectively; The fourth water valve is connected to the heating core, the water-cooled condenser, the second water valve, and the second water pump.

[0013] In some embodiments, the fifth and sixth water valves are three-way water valves; The fifth water valve is connected to the third heat exchanger, the drive motor, and the third water valve. The sixth water valve is connected to the third water pump, the second heat exchanger, and the heating core.

[0014] In some embodiments, a temperature damper is also included, wherein the temperature damper, the warm air core, and the evaporator are connected inside the air conditioning unit.

[0015] In some embodiments, the first water valve, the second water valve, the third water valve, the fourth water valve, the fifth water valve, and the sixth water valve are controlled by the motor control unit to switch the coolant circuit between cooling mode, heating mode, dehumidification mode, external heat exchanger defrosting mode, motor heating battery mode, motor heating passenger compartment mode, motor and battery heating passenger compartment mode, motor cooling mode, and motor and battery cooling mode.

[0016] Compared with the prior art, the present invention has the following beneficial effects: (1) The present invention can use a heat pump to heat the battery, which is more energy-efficient than the commonly used electric heating method; (2) The present invention can make full and reasonable use of the waste heat generated by the motor, motor control unit and even the battery during operation to provide heat for the vehicle; (3) The present invention can also directly use a fan and a heat sink to dissipate heat from the battery without turning on the compressor, thereby further improving the energy efficiency of the thermal management system; (4) The refrigerant circuit structure of the present invention is very simple, highly reliable and easy to control; the coolant circuit structure is flexible and can be easily configured into different working modes to make the system energy efficiency optimal. Attached Figure Description

[0017] Other features, objects, and advantages of the present invention will become more apparent from the following detailed description of non-limiting embodiments with reference to the accompanying drawings: Figure 1 A schematic diagram of a thermal management system provided in Embodiment 1 of the present invention; Figure 2 A schematic diagram of the refrigerant circuit provided in Embodiment 1 of the present invention; Figure 3 A schematic diagram of operation in cooling mode provided in Embodiment 1 of the present invention; Figure 4 A schematic diagram of operation in heating mode provided in Embodiment 1 of the present invention; Figure 5 A schematic diagram of operation in dehumidification mode provided in Embodiment 1 of the present invention; Figure 6 A schematic diagram of the operation of the external heat exchanger in defrosting mode provided in Embodiment 1 of the present invention; Figure 7 The present invention provides a schematic diagram of the operation of the coolant circuit in the motor-heated battery mode; Figure 8 A schematic diagram of the operation of the coolant circuit in the motor-heated passenger compartment mode provided by the present invention; Figure 9 The present invention provides a schematic diagram of the operation of the coolant circuit in the motor and battery heated occupant compartment mode; Figure 10 The present invention provides a schematic diagram of the operation of the coolant circuit in motor cooling mode; Figure 11 The present invention provides a schematic diagram of the operation of the coolant circuit in the motor and battery heat dissipation modes; Figure 12 The thermal management system diagram provided in Embodiment 2 of the present invention; Figure 13 A schematic diagram of the refrigerant circuit provided in Embodiment 2 of the present invention.

[0018] Numbering on the map: 1. First throttling mechanism; 2. First heat exchange device; 3. Second throttling mechanism; 4. Evaporator; 5. Gas-liquid separator; 6. Compressor; 7. Water-cooled condenser; 8. Liquid storage tank; 9. Drive battery; 10. Second heat exchange device; 11. First water valve (ends 111, 112, 113, and 114); 12. Third water valve (ends 121, 122, 123, and 124); 13. First water pump; 14. Drive motor; 15. Motor control unit; 16. Second first water pump; 17. Fourth water valve (ends 171, 172, 173, and 174); 18. Warm air core; 19. Sixth water valve; 20. Third water pump; 21. Electric heater; 22. Second water valve (ends 221, 222, 223, and 224); 23. Fifth water valve; 24. Third heat exchange device; 25. Temperature damper. Detailed Implementation

[0019] The present invention will now be described in detail with reference to specific embodiments. These embodiments will help those skilled in the art to further understand the present invention, but do not limit the invention in any way. It should be noted that those skilled in the art can make several changes and improvements without departing from the concept of the present invention. These all fall within the protection scope of the present invention.

[0020] Example 1 This invention provides a thermal management system for electric vehicles, such as... Figure 1-11 As shown, it includes a refrigerant circuit, a coolant circuit, and a battery circuit. The coolant circuit is connected to both the refrigerant circuit and the battery circuit, and the refrigerant circuit is connected to the battery circuit. It also includes a temperature damper 25, and the temperature damper 25, the heater core 18 in the coolant circuit, and the evaporator 4 in the refrigerant circuit are connected inside the air conditioning unit.

[0021] like Figure 2As shown, the refrigerant circuit includes a first throttling mechanism 1, a first heat exchange device 2, a second throttling mechanism 3, an evaporator 4, a gas-liquid separator 5, a compressor 6, and a water-cooled condenser 7. One end of the gas-liquid separator 5 is connected to both the first heat exchange device 2 and the evaporator 4, and the other end is connected to the compressor 6. The compressor 6 is connected to one end of the water-cooled condenser 7, and the other end is connected to both the first throttling mechanism 1 and the second throttling mechanism 3. The first throttling mechanism 1 is connected to the first heat exchange device 2, and the second throttling mechanism 3 is connected to the evaporator 4. High-temperature, high-pressure superheated gaseous refrigerant flows out from the compressor 6 and exchanges heat with the coolant in the coolant circuit in the water-cooled condenser 7, thus becoming a subcooled liquid refrigerant. After flowing out of the water-cooled condenser 7, the refrigerant, depending on the system's operating mode, passes through the first throttling mechanism 1 to reduce its pressure, becoming a saturated gas-liquid two-phase refrigerant and absorbing heat from the coolant circuit in the first heat exchanger 2; or, after being throttled and depressurized by the second throttling mechanism 3, it becomes a saturated gas-liquid two-phase refrigerant and absorbs heat from the passenger compartment in the evaporator 4; or, it simultaneously flows through the first throttling mechanism 1 and the second throttling mechanism 3, simultaneously absorbing heat in both the first heat exchanger 2 and the evaporator 4. The refrigerant flowing through the first heat exchanger 2 or the evaporator 4 then returns to the compressor 6 via the gas-liquid separator 5, thus completing the refrigerant cycle.

[0022] The battery circuit includes a drive battery 9, a second heat exchange device 10, a first water valve 11, a third water valve 12, and a first water pump 13. One end of the drive battery 9 is connected to the second heat exchange device 10, and the other end of the drive battery 9 is connected to the first water pump 13. The first water pump 13 is connected to the third water valve 12, and the third water valve 12 is connected to the first water valve 11. The first water valve 11 is connected to the second heat exchange device 10. The first water valve 11 is connected to both the refrigerant circuit and the coolant circuit, and the third water valve 12 is connected to the coolant circuit.

[0023] The coolant circuit includes a drive motor 14, a motor control unit 15, a second water pump 136, a fourth water valve 17, a heater core 18, a sixth water valve 19, a third water pump 20, an electric heater 21, a second water valve 22, a fifth water valve 23, and a third heat exchanger 24. The motor control unit 15 is connected to the drive motor 14, the drive motor 14 is connected to the fifth water valve 23, the third heat exchanger 24 is connected to both the drive motor 14 and the fifth water valve 23, and the fifth water valve 23 is connected to the third water pump 20. Valve 12, the third water valve 12 is connected to the second water valve 22, the second water valve 22 is connected to the fourth water valve 17, the fourth water valve 17 is connected to the water-cooled condenser 7, the water-cooled condenser 7 is connected to the electric heater 21, the electric heater 21 is connected to the third water pump 20, the third water pump 20 is connected to the sixth water valve 19, the sixth water valve 19 is connected to the heater core 18, the heater core 18 is connected to the fourth water valve 17, the fourth water valve 17 is connected to the second first water pump 136, the second first water pump 136 is connected to the motor control unit 15.

[0024] The motor control unit 15 connects to the refrigerant circuit, the coolant circuit, and the battery circuit. The first water valve 11, the second water valve 22, the third water valve 12, and the fourth water valve 17 are four-way valves, while the fifth water valve 23 and the sixth water valve 19 are three-way valves. The four-way connection terminals of the first water valve 11 are designated as terminals 111, 112, 113, and 114, respectively. Terminal 114 connects to the first heat exchanger 2, terminal 112 connects to the second water valve 22, terminal 113 connects to the third water valve 12, and terminal 114 connects to the second heat exchanger 10. The four-way connection terminals of the second water valve 22 are designated as terminals 221, 222, 223, and 224, respectively. Terminal 221 connects to the first heat exchanger 2, terminal 222 connects to the fourth water valve 17, terminal 223 connects to the third water valve 12, and terminal 224 connects to the first water valve 11. The four-way connection terminals of the third water valve 12 are designated as terminals 121, 122, 123, and 124. Terminal 121 connects to the first water valve 11, terminal 122 connects to the second water valve 22, terminal 123 connects to the fifth water valve 23, and terminal 124 connects to the first water pump 13. The four-way connection terminals of the fourth water valve 17 are designated as terminals 171, 172, 173, and 174. Terminal 171 connects to the heater core 18, terminal 172 connects to the second first water pump 136, terminal 173 connects to the second water valve 22, and terminal 174 connects to the water-cooled condenser 7. The three-way connection terminals of the fifth water valve 23 are designated as terminals 231, 232, and 233. Terminal 231 connects to the third heat exchange device 24, terminal 232 connects to the drive motor 14, and terminal 233 connects to the third water valve 12. The three-way connection ends of the sixth water valve 19 are respectively designated as end 191, end 192 and end 193. End 191 is connected to the third water pump 20, end 192 is connected to the second heat exchange device 10, and end 193 is connected to the warm air core 18.

[0025] The first water valve 11, the second water valve 22, the third water valve 12, the fourth water valve 17, the fifth water valve 23, and the sixth water valve 19 are controlled by the motor control unit 15 to switch the coolant circuit between cooling mode, heating mode, dehumidification mode, external heat exchanger defrosting mode, motor-heated battery mode, motor-heated passenger compartment mode, motor and battery-heated passenger compartment mode, motor cooling mode, and motor and battery cooling mode. All components are connected by connecting pipes.

[0026] like Figure 3As shown, in cooling mode, terminals 222 and 223 of the second water valve 22 are connected, terminals 122 and 123 of the third water valve 12 are connected, terminals 173 and 174, and terminals 171 and 172 of the fourth water valve 17 are connected, terminals 231 and 233 of the fifth water valve 23 are connected, and terminals 191 and 193 of the sixth water valve 19 are connected. The second water pump 16 and the third water pump 20 are also activated. This allows the coolant circuit to dissipate the heat from the refrigerant in the water-cooled condenser 7 into the outside air through the third heat exchanger 24. The first throttling mechanism 1 can be activated as needed, allowing the coolant circuit to cool the refrigerant in the water-cooled condenser 7 within the first heat exchanger 2. At this time, terminals 111 and 114 of the first water valve 11 are connected, terminals 112 and 113 are connected, terminals 221 and 224 of the second water valve 22 are connected, and terminals 121 and 124 of the third water valve 12 are connected. The coolant, cooled and de-temperatured in the first heat exchanger 2, can flow through the drive battery to achieve battery cooling. The second throttling mechanism 3 can also be opened, allowing the refrigerant to absorb heat from the passenger compartment in the evaporator 4, thus achieving passenger compartment cooling. At this time, the temperature damper 25 is generally in the fully cold position, preventing the heater core 18 from effectively exchanging heat with the air in the air conditioning unit, thereby avoiding affecting the cooling effect of the air conditioning unit.

[0027] like Figure 4 As shown, in heating mode, terminals 111 and 112 of the first water valve 11 are connected, and terminals 113 and 114 are connected; terminals 221 and 222 of the second water valve 22 are connected, and terminals 223 and 224 are connected; terminals 121 and 124 of the third water valve 12 are connected, and terminals 122 and 123 are connected; terminals 171 and 174 of the fourth water valve 17 are connected, and terminals 172 and 173 are connected; and terminals 231 and 233 of the fifth water valve 23 are connected. The first throttling mechanism 1 is open, allowing the refrigerant circuit to absorb heat from the cooling circuit in the first heat exchanger 2, while the cooling circuit absorbs heat from the ambient air through the third heat exchanger 24 and simultaneously absorbs waste heat generated by the drive motor 14 and the motor control unit 15. The second throttling mechanism 3 is closed, preventing refrigerant from passing through the evaporator 4. As needed, terminals 191 and 192, 191 and 193, or both 191 and 192 and 193 of the sixth water valve 19 can be connected, allowing heat from the refrigerant in the water-cooled condenser 7 to be released into the passenger compartment via the heater core 18 for heating, or to heat the drive battery 9 by heating the coolant in the battery circuit via the second heat exchanger 10. When heating the passenger compartment, the third water pump 20 is activated, and the temperature damper 25 is in a fully heated state. When heating the drive battery 9, the first water pump 13 is activated.

[0028] like Figure 5As shown, in dehumidification mode, the second throttling mechanism 3 is activated, and the refrigerant exchanges heat with the air flowing through the evaporator 4 in the air conditioning unit, thereby cooling and dehumidifying the passenger compartment. In this mode, terminals 111 and 112 of the first water valve 11 are connected, terminals 221 and 222, and terminals 223 and 224 of the second water valve 22 are connected, terminals 122 and 123 of the third water valve 12 are connected, terminals 171 and 174, and terminals 172 and 173 of the fourth water valve 17 are connected, terminals 231 and 233 of the fifth water valve 23 are connected, and terminals 191 and 193 of the sixth water valve 19 are connected. The second water pump 16 and the third water pump 20 are activated. The air, which is cooler after passing through the evaporator 4, is reheated by the heater core 18 to become air with a suitable temperature and lower humidity before entering the passenger compartment. The first throttling mechanism 1 can be opened as needed, and the refrigerant circuit absorbs the waste heat generated by the drive motor 14 and motor control unit 15 during operation through the first heat exchange device 2. At this time, the temperature damper 25 can be adjusted according to the heating needs of the passenger compartment.

[0029] like Figure 6 As shown, when the ambient humidity is high, the system is prone to frost formation on the external heat exchanger when operating in heat pump mode. If the frost is severe, defrosting is required. When in defrosting mode for the external heat exchanger, compressor 6 is not working, and the refrigerant circuit is closed. Terminals 222 and 223 of the second water valve 22 are connected; terminals 122 and 123 of the third water valve 12 are connected; terminals 171 and 172, 173 and 174, and 171 and 172 of the fourth water valve 17 are connected; terminals 231 and 233 of the fifth water valve 23 are connected; and terminals 191 and 193 of the sixth water valve 19 are connected. The second water pump 16 and the third water pump 20 are activated. The electric heater 21 activates to heat the coolant, and the hot coolant flows through the third heat exchanger 24 to remove the surface frost. Simultaneously, the hot air passing through the heater core 18 heats the passenger compartment, ensuring passenger comfort in defrosting mode.

[0030] The electric vehicle drive motor 14, motor control unit 15 and drive battery 9 generate heat when they are working. When the passenger compartment or drive battery 9 needs to be heated, the reasonable use of this heat can effectively improve thermal management efficiency, because it can reduce the energy consumption of electric heater 21 or compressor 6. Figure 7 , Figure 8 and Figure 9 The operation modes of the coolant circuit are shown respectively: heating the drive battery 9 using the drive motor 14 and motor control unit 15, heating the passenger compartment using the drive motor 14 and motor control unit 15, and heating the passenger compartment using the drive motor 14, motor control unit 15, and drive battery 9.

[0031] like Figure 7As shown, when in motor-heated battery mode, terminals 113 and 114 of the first water valve 11, terminals 222 and 223 of the second water valve 22, terminals 121 and 122, 123 and 124 of the third water valve 12, terminals 172 and 173 of the fourth water valve 17 are connected, and terminals 232 and 233 of the fifth water valve 23 are connected, and the first water pump 13 and the second water pump 16 are turned on.

[0032] like Figure 8 As shown, when in the motor-heated passenger compartment mode, the 222 and 223 terminals of the second water valve 22, the 122 and 123 terminals of the third water valve 12, the 171 and 172 terminals, the 173 and 174 terminals of the fourth water valve 17 are connected, and the 191 and 193 terminals of the sixth water valve 19 are connected, thus activating the second water pump 16 and the third water pump 20.

[0033] like Figure 9 As shown, when in the motor and battery heated occupant cabin mode, the 113 and 114 terminals of the first water valve 11, the 221 and 224, 222 and 223 terminals of the second water valve 22, the 121 and 122, 123 and 124 terminals of the third water valve 12, the 171 and 172, 173 and 174 terminals of the fourth water valve 17 are connected, the 232 and 233 terminals of the fifth water valve 23, and the 191 and 193 terminals of the sixth water valve 19 are connected, and the first water pump 13, the second water pump 16 and the third water pump 20 are activated.

[0034] When components such as the drive motor 14, motor control unit 15, and drive battery 9 become too hot, they need to be cooled to ensure their normal operation. Figure 10 As shown, when in motor cooling mode, cooling of the drive motor 14 is achieved through the third heat exchange device 24. Terminals 113 and 114 of the first water valve 11, terminals 222 and 223 of the second water valve 22, terminals 122 and 123 of the third water valve 12, terminals 172 and 173 of the fourth water valve 17, and terminals 231 and 233 of the fifth water valve 23 are connected, and the second water pump 16 is turned on.

[0035] There are two ways to cool the battery, one is as follows: Figure 3 As shown, the drive battery is cooled by refrigerant flowing through the first heat exchanger 2. This method is generally used when the ambient temperature is high. When the ambient temperature is low, heat can be dissipated directly to the outside environment through the third heat exchanger 24, such as... Figure 11As shown, compressor 6 does not need to be turned on at this time, thus achieving energy saving. When in motor and battery cooling mode, terminals 113 and 114 of the first water valve 11, terminals 222 and 223 of the second water valve 22, terminals 121 and 122, 123 and 124 of the third water valve 12, terminals 172 and 173 of the fourth water valve 17 are connected, and terminals 231 and 233 of the fifth water valve 23 are connected, turning on the first water pump 13 and the second water pump 16.

[0036] Example 2 This embodiment 2 is based on embodiment 1, except that the gas-liquid separator 5 in the refrigerant circuit of embodiment 1 is replaced with a liquid storage tank 8, as detailed below: like Figure 12-13 The high-pressure cooling circuit includes a compressor 6, a water-cooled condenser 7, and a liquid storage tank 8. One end of the compressor 6 is connected to the first heat exchange device 2 and the evaporator 4, respectively. The other end of the compressor 6 is connected to the water-cooled condenser 7. The water-cooled condenser 7 is connected to one end of the liquid storage tank 8, and the other end of the liquid storage tank 8 is connected to the first throttling mechanism 1 and the second throttling mechanism 3, respectively.

[0037] The main difference between this system and the thermal management system in Example 1 is that the gas-liquid separator 5 in the refrigerant circuit of Example 1 is replaced with a liquid storage tank 8, and the position is adjusted from before the compressor 6 to after the water-cooled condenser 7, before the first throttling mechanism 1 and the second throttling mechanism 3. The coolant circuit remains unchanged, and the system operation mode is the same as in Example 1.

[0038] In the description of this application, it should be understood that the terms "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application.

[0039] Specific embodiments of the present invention have been described above. It should be understood that the present invention is not limited to the specific embodiments described above, and those skilled in the art can make various changes or modifications within the scope of the claims, which do not affect the essence of the present invention. Unless otherwise specified, the embodiments and features described in this application can be arbitrarily combined with each other.

Claims

1. A thermal management system for electric vehicles, characterized in that, It includes a refrigerant circuit, a coolant circuit, and a battery circuit. The coolant circuit is connected to both the refrigerant circuit and the battery circuit, and the refrigerant circuit is connected to the battery circuit. The refrigerant circuit includes a high-pressure cooling circuit, a first throttling mechanism (1), a first heat exchange device (2), a second throttling mechanism (3), and an evaporator (4). One end of the high-pressure cooling circuit is connected to the first heat exchange device (2) and the evaporator (4), and the other end of the high-pressure cooling circuit is connected to the first throttling mechanism (1) and the second throttling mechanism (3). The first throttling mechanism (1) is connected to the first heat exchange device (2), and the second throttling mechanism (3) is connected to the evaporator (4). The refrigerant in the high-pressure cooling circuit flows into the first throttling mechanism (1) and / or the second throttling mechanism (3). After being depressurized by the first throttling mechanism (1), the refrigerant flows into the first heat exchange device (2) to absorb heat from the coolant circuit. Alternatively, the refrigerant after being depressurized by the second throttling mechanism (3) flows into the evaporator (4) to absorb heat from the passenger compartment. The refrigerant that absorbs heat from the first heat exchange device (2) and / or the evaporator (4) then flows back into the high-pressure cooling circuit for refrigerant circulation. The high-pressure cooling circuit includes a gas-liquid separator (5), a compressor (6), and a water-cooled condenser (7). One end of the gas-liquid separator (5) is connected to the first heat exchange device (2) and the evaporator (4), respectively. The other end of the gas-liquid separator (5) is connected to the compressor (6), and the compressor (6) is connected to one end of the water-cooled condenser (7). The other end of the water-cooled condenser (7) is connected to the first throttling mechanism (1) and the second throttling mechanism (3), respectively. The high-pressure cooling circuit includes a compressor (6), a water-cooled condenser (7), and a liquid storage tank (8). One end of the compressor (6) is connected to the first heat exchange device (2) and the evaporator (4), respectively. The other end of the compressor (6) is connected to the water-cooled condenser (7). The water-cooled condenser (7) is connected to one end of the liquid storage tank (8), and the other end of the liquid storage tank (8) is connected to the first throttling mechanism (1) and the second throttling mechanism (3), respectively. The coolant circuit includes a drive motor (14) and a motor control unit (15). When in cooling mode, the first throttling mechanism (1) can be opened as needed, and the coolant circuit will cool the refrigerant in the water-cooled condenser (7) in the first heat exchange device (2); the second throttling mechanism (3) can also be opened, so that the refrigerant absorbs the heat in the passenger compartment in the evaporator (4), thereby realizing the function of cooling the passenger compartment. When in heating mode, the first throttling mechanism (1) is open, so that the refrigerant circuit absorbs heat from the cooling circuit in the first heat exchange device (2), while the cooling circuit absorbs heat from the ambient air through the third heat exchange device (24) and simultaneously absorbs the waste heat generated by the drive motor (14) and the motor control unit (15); the second throttling mechanism (3) is closed, and the refrigerant cannot pass through the evaporator (4). When in dehumidification mode, the second throttling mechanism (3) is turned on, and the refrigerant exchanges heat with the air flowing through the evaporator (4) in the air conditioning unit to cool and dehumidify the passenger compartment; if necessary, the first throttling mechanism (1) can be turned on, and the refrigerant circuit absorbs the waste heat generated by the drive motor (14) and motor control unit (15) during operation through the first heat exchange device (2); The battery circuit includes a drive battery (9), a second heat exchange device (10), a first water valve (11), a third water valve (12), and a first water pump (13). One end of the drive battery (9) is connected to the second heat exchange device (10), and the other end of the drive battery (9) is connected to the first water pump (13). The first water pump (13) is connected to the third water valve (12), and the third water valve (12) is connected to the first water valve (11). The first water valve (11) is connected to the second heat exchange device (10). The first water valve (11) is connected to the refrigerant circuit and the coolant circuit respectively, and the third water valve (12) is connected to the coolant circuit. The coolant circuit includes a second water pump (16), a fourth water valve (17), a heater core (18), a sixth water valve (19), a third water pump (20), an electric heater (21), a second water valve (22), a fifth water valve (23), and a third heat exchanger (24). The motor control unit (15) is connected to the drive motor (14), the drive motor (14) is connected to the fifth water valve (23), the third heat exchanger (24) is connected to the drive motor (14) and the fifth water valve (23), the fifth water valve (23) is connected to the third water valve (12), and the third water valve (12) is connected to the... The second water valve (22) is connected to the fourth water valve (17), the fourth water valve (17) is connected to the water-cooled condenser (7), the water-cooled condenser (7) is connected to the electric heater (21), the electric heater (21) is connected to the third water pump (20), the third water pump (20) is connected to the sixth water valve (19), the sixth water valve (19) is connected to the heater core (18), the heater core (18) is connected to the fourth water valve (17), the fourth water valve (17) is connected to the second water pump (16), and the second water pump (16) is connected to the motor control unit (15). The first water valve (11), the second water valve (22), the third water valve (12) and the fourth water valve (17) are four-way water valves; The first water valve (11) is connected to the first heat exchange device (2), the second heat exchange device (10), the third water valve (12) and the second water valve (22) respectively. The second water valve (22) is connected to the first water valve (11), the third water valve (12), the fourth water valve (17) and the first heat exchange device (2) respectively. The third water valve (12) is connected to the first water valve (11), the first water pump (13), the fifth water valve (23) and the second water valve (22) respectively. The fourth water valve (17) is connected to the warm air core (18), the water-cooled condenser (7), the second water valve (22), and the second water pump (16).

2. The electric vehicle thermal management system according to claim 1, characterized in that, The motor control unit (15) is connected to the refrigerant circuit, the coolant circuit and the battery circuit.

3. The electric vehicle thermal management system according to claim 1, characterized in that, The fifth water valve (23) and the sixth water valve (19) are three-way water valves; The fifth water valve (23) is connected to the third heat exchange device (24), the drive motor (14) and the third water valve (12) respectively. The sixth water valve (19) is connected to the third water pump (20), the second heat exchange device (10), and the warm air core (18).

4. The electric vehicle thermal management system according to claim 3, characterized in that, It also includes a temperature damper (25), the temperature damper (25), the warm air core (18) and the evaporator (4) connected inside the air conditioning unit.

5. The electric vehicle thermal management system according to any one of claims 1-4, characterized in that, The first water valve (11), the second water valve (22), the third water valve (12), the fourth water valve (17), the fifth water valve (23), and the sixth water valve (19) control the valve opening and closing through the motor control unit (15), thereby driving the coolant circuit to switch between cooling mode, heating mode, dehumidification mode, external heat exchanger defrosting mode, motor heating battery mode, motor heating passenger compartment mode, motor and battery heating passenger compartment mode, motor cooling mode, and motor and battery cooling mode.

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