Thermal management system, thermal management method and electric vehicle

Abstract

The present application provides a thermal management system, a thermal management method and an electric vehicle. The thermal management system includes an air conditioning refrigerant circuit and a secondary refrigerant circuit, the air conditioning refrigerant circuit includes a compressor, an enthalpy increasing device, a first heat exchanger and an intermediate heat exchanger, the secondary refrigerant circuit includes a regulating branch, a battery branch, a motor branch and an off-vehicle branch, the off-vehicle branch includes a first pipeline and a second pipeline in parallel, an off-vehicle heat exchanger is arranged on the first pipeline, the first end of the secondary refrigerant heat exchange pipeline can be selectively connected to the first pipeline or the second pipeline, the second end of the secondary refrigerant heat exchange pipeline can be selectively connected to the regulating branch or the motor branch, the regulating branch, the battery branch, the motor branch and the off-vehicle branch are connected through a first four-way valve, and the enthalpy increasing device is connected to the air supply port of the compressor through an air supply pipeline. According to the thermal management system of the present application, the thermal energy of the whole vehicle can be reasonably distributed, the energy utilization rate of the whole vehicle can be improved, and the cruising range can be improved.

Description

Technical Field

[0001] The present application relates to the technical field of electric vehicles, and in particular to a thermal management system, a thermal management method and an electric vehicle. Background Art

[0002] Pure electric vehicles are green and environmentally friendly, have low operating costs, and have good market prospects, and are favored by many companies. The current problem with pure electric vehicles is that their driving range is short. The fundamental reason is that the operating temperature of the battery affects the battery's charging and discharging capacity and life. Especially under low temperature conditions, the performance decays severely and cannot output enough power to drive the motor to work normally. At the same time, the temperature of the drive motor cannot be too high. If the internal temperature of the motor is too high, the motor efficiency will decrease. In severe cases, it will cause the coil inside the motor to burn or even cause the coil to short-circuit and damage the motor. On the other hand, the heating capacity of automotive air conditioners in the form of air source heat pumps will also decrease as the ambient temperature drops. Therefore, it is urgent to develop an efficient vehicle thermal management system that can reasonably distribute the thermal energy of the vehicle, improve the energy utilization rate of the vehicle, and increase the driving range. Summary of the invention

[0003] Therefore, the technical problem to be solved by the present application is to provide a thermal management system, a thermal management method and an electric vehicle, which can reasonably distribute the thermal energy of the entire vehicle, improve the energy utilization rate of the entire vehicle, and increase the cruising range.

[0004] In order to solve the above problems, the present application provides a thermal management system, including an air-conditioning refrigerant circuit and a coolant circuit. The air-conditioning refrigerant circuit includes a compressor, an enthalpy increasing device, a first heat exchanger and an intermediate heat exchanger. The coolant circuit includes a coolant heat exchange pipeline, a regulating branch, a battery branch, a motor branch and an off-vehicle branch. The off-vehicle branch includes a first pipeline and a second pipeline in parallel. The coolant heat exchange pipeline is heat-exchangedly connected to the first heat exchanger. The off-vehicle heat exchanger is arranged on the first pipeline. The first end of the coolant heat exchange pipeline can be selectively connected to the first end of the first pipeline or the second pipeline through a first three-way valve. The second end of the coolant heat exchange pipeline can be selectively connected to the first end of the regulating branch or the motor branch through a second three-way valve. The regulating branch, the battery branch, the motor branch and the second ends of the off-vehicle branch are connected through a first four-way valve. The regulating branch is connected to the battery branch through a heat exchange branch. The heat exchange branch is heat-exchangedly connected to the intermediate heat exchanger. The enthalpy increasing device is connected to the air supply port of the compressor through an air supply pipeline.

[0005] Preferably, a first pump is provided on the regulating branch, and the heat exchange branch is connected to the pipeline between the second three-way valve and the first pump.

[0006] Preferably, a motor controller and / or a motor is provided on the motor branch, and a second pump is provided on the pipeline connecting the motor controller and / or the motor and the first four-way valve.

[0007] Preferably, a battery assembly is provided on the battery branch, and the heat exchange branch is connected to an end of the battery assembly away from the first four-way valve.

[0008] A first two-way valve is provided on a pipeline connected to the second three-way valve at one end of the battery assembly away from the first four-way valve; and / or a second two-way valve is provided on the heat exchange branch.

[0009] Preferably, the off-vehicle branch further includes an expansion water tank, and the first pipeline and the second pipeline are connected in parallel and then connected to the first four-way valve, and the expansion water tank is arranged on the pipeline between the parallel pipeline and the first four-way valve.

[0010] Preferably, the air-conditioning refrigerant circuit further includes a second four-way valve, and the compressor, the first heat exchanger and the intermediate heat exchanger are connected to the second four-way valve.

[0011] Preferably, the air conditioning refrigerant circuit also includes a second heat exchanger, the second heat exchanger is connected in parallel with the intermediate heat exchanger, a first electronic expansion valve is provided on the branch where the second heat exchanger is located, and a second electronic expansion valve is provided on the branch where the intermediate heat exchanger is located.

[0012] Preferably, a gas-liquid separator is provided at the suction end of the compressor.

[0013] Preferably, when the air conditioning refrigerant circuit is in a cooling state, the refrigerant flow direction in the intermediate heat exchanger is the same as the coolant flow direction, and when the air conditioning refrigerant circuit is in a heating state, the refrigerant flow direction in the intermediate heat exchanger is opposite to the coolant flow direction.

[0014] Preferably, the enthalpy increasing device is arranged on the pipeline between the first heat exchanger and the intermediate heat exchanger, and a third electronic expansion valve is arranged on the pipeline between the enthalpy increasing device and the first heat exchanger.

[0015] Preferably, the enthalpy increasing device includes a subcooler, a fourth electronic expansion valve is arranged on the inlet pipe of the subcooler, and the outlet pipe of the subcooler is connected to the air supply pipeline; or, the enthalpy increasing device includes a flasher, and the air outlet of the flasher is connected to the air supply pipeline.

[0016] According to another aspect of the present application, an electric vehicle is provided, comprising a thermal management system, which is the thermal management system described above.

[0017] According to another aspect of the present application, a thermal management method of the thermal management system is provided, comprising:

[0018] Select the thermal management mode;

[0019] The thermal management system is controlled according to the selected thermal management mode.

[0020] Preferably, the step of controlling the thermal management system according to the selected thermal management mode includes:

[0021] Control the air conditioning refrigerant circuit to be in cooling mode;

[0022] Control the first three-way valve to be connected to the first pipeline, control the second three-way valve to be connected to the motor branch, control the heat exchange branch to be connected to the battery branch, control the battery branch to be disconnected from the motor branch, control the adjustment branch to be connected to the battery branch, and control the motor branch to be connected to the branch outside the vehicle.

[0023] Preferably, the step of controlling the thermal management system according to the selected thermal management mode includes:

[0024] Control the air conditioning refrigerant circuit to be in heating mode;

[0025] Control the first three-way valve to be connected to the first pipeline, control the second three-way valve to be connected to the motor branch, control the heat exchange branch to be connected to the battery branch, control the battery branch to be disconnected from the motor branch, control the adjustment branch to be connected to the battery branch, and control the motor branch to be connected to the branch outside the vehicle.

[0026] Preferably, the step of controlling the thermal management system according to the selected thermal management mode includes:

[0027] Control the air conditioner refrigerant circuit to be in cooling mode, and control the first electronic expansion valve to be closed;

[0028] Control the first three-way valve to be connected to the first pipeline, control the second three-way valve to be connected to the motor branch, control the heat exchange branch to be connected to the battery branch, control the battery branch to be disconnected from the motor branch, control the adjustment branch to be connected to the battery branch, and control the motor branch to be connected to the branch outside the vehicle.

[0029] Preferably, the step of controlling the thermal management system according to the selected thermal management mode includes:

[0030] Control the air conditioner refrigerant circuit to be in heating mode, and control the first electronic expansion valve to be closed;

[0031] Control the first three-way valve to be connected to the first pipeline, control the second three-way valve to be connected to the motor branch, control the heat exchange branch to be connected to the battery branch, control the battery branch to be disconnected from the motor branch, control the adjustment branch to be connected to the battery branch, and control the motor branch to be connected to the branch outside the vehicle.

[0032] Preferably, the step of controlling the thermal management system according to the selected thermal management mode includes:

[0033] Control the air conditioner refrigerant circuit to be in heating mode, and control the first electronic expansion valve to be closed;

[0034] Control the first three-way valve to be connected with the second pipeline, control the second three-way valve to be connected with the motor branch, control the heat exchange branch to be connected with the battery branch, control the battery branch to be disconnected from the motor branch, control the adjustment branch to be connected with the battery branch, and control the motor branch to be connected with the branch outside the vehicle.

[0035] Preferably, the step of controlling the thermal management system according to the selected thermal management mode includes:

[0036] Control the air conditioning refrigerant circuit to be in heating mode;

[0037] Control the first three-way valve to be connected with the second pipeline, control the second three-way valve to be connected with the motor branch, control the heat exchange branch to be connected with the battery branch, control the battery branch to be disconnected from the motor branch, control the adjustment branch to be connected with the battery branch, and control the motor branch to be connected with the branch outside the vehicle.

[0038] Preferably, the step of controlling the thermal management system according to the selected thermal management mode includes:

[0039] Control the air conditioner refrigerant circuit to be in heating mode, and control the second electronic expansion valve to be closed;

[0040] Control the first three-way valve to be connected to the first pipeline, control the second three-way valve to be connected to the motor branch, control the heat exchange branch to be connected to the battery branch, control the battery branch to be disconnected from the motor branch, control the adjustment branch to be connected to the off-vehicle branch, and control the motor branch to be connected to the battery branch.

[0041] Preferably, the step of controlling the thermal management system according to the selected thermal management mode includes:

[0042] Control the air conditioner refrigerant circuit to be in heating mode, and control the second electronic expansion valve to be closed;

[0043] Control the first three-way valve to be connected to the first pipeline, control the second three-way valve to be connected to the regulating branch, control the heat exchange branch to be disconnected from the battery branch, control the battery branch to be connected to the motor branch, control the regulating branch to be connected to the battery branch, and control the motor branch to be connected to the branch outside the vehicle.

[0044] Preferably, the step of controlling the thermal management system according to the selected thermal management mode includes:

[0045] Control the air conditioner refrigerant circuit to be in heating mode, and control the second electronic expansion valve to be closed;

[0046] Control the first three-way valve to be connected with the second pipeline, control the second three-way valve to be connected with the regulating branch, control the heat exchange branch to be disconnected from the battery branch, control the battery branch to be connected with the motor branch, control the regulating branch to be connected with the battery branch, and control the motor branch to be connected with the branch outside the vehicle.

[0047] Preferably, the step of controlling the thermal management system according to the selected thermal management mode includes:

[0048] Control the air conditioning refrigerant circuit to be in shutdown state;

[0049] Control the first three-way valve to be connected to the first pipeline, control the second three-way valve to be connected to the regulating branch, control the heat exchange branch to be disconnected from the battery branch, control the battery branch to be connected to the motor branch, control the regulating branch to be connected to the battery branch, and control the motor branch to be connected to the branch outside the vehicle.

[0050] Preferably, the step of controlling the thermal management system according to the selected thermal management mode includes:

[0051] Control the air conditioning refrigerant circuit to be in shutdown state;

[0052] Control the first three-way valve to be connected with the second pipeline, control the second three-way valve to be connected with the motor branch, control the heat exchange branch to be connected with the battery branch, control the battery branch to be disconnected from the motor branch, control the adjustment branch to be connected with the off-vehicle branch, and control the motor branch to be connected with the battery branch.

[0053] The thermal management system provided in the present application includes an air-conditioning refrigerant circuit and a coolant circuit. The air-conditioning refrigerant circuit includes a first heat exchanger and an intermediate heat exchanger. The coolant circuit includes a coolant heat exchange pipeline, a regulating branch, a battery branch, a motor branch and an off-vehicle branch. The off-vehicle branch includes a first pipeline and a second pipeline connected in parallel. The coolant heat exchange pipeline is connected to the first heat exchanger for heat exchange. The off-vehicle heat exchanger is arranged on the first pipeline. The first end of the coolant heat exchange pipeline can be selectively connected to the first end of the first pipeline or the second pipeline through a first three-way valve. The second end of the coolant heat exchange pipeline can be selectively connected to the first end of the regulating branch or the motor branch through a second three-way valve. The second ends of the regulating branch, the battery branch, the motor branch and the off-vehicle branch are connected through a first four-way valve. The regulating branch is connected to the battery branch through a heat exchange branch, and the heat exchange branch is connected to the intermediate heat exchanger for heat exchange. The thermal management system of the present application can integrate the air-conditioning system, the battery thermal management system and the drive motor cooling system into a complete vehicle thermal management system, realize the temperature control of the vehicle compartment, battery components, motors, etc., make full use of and reasonably distribute the heat of each part, so that the operating temperature of the battery system and the motor system is maintained within the operating temperature range, the vehicle heat distribution is more efficient, the energy utilization is more reasonable, and the thermal management of the whole vehicle can be effectively realized, the energy utilization rate of the whole vehicle is improved, and the cruising range is increased. BRIEF DESCRIPTION OF THE DRAWINGS

[0054] Figure 1 A cycle structure diagram of a thermal management system according to a first embodiment of the present application;

[0055] Figure 2A cycle structure diagram of a thermal management system according to a second embodiment of the present application;

[0056] Figure 3 A first thermal management mode diagram of the thermal management system of an embodiment of the present application;

[0057] Figure 4 A second thermal management mode diagram of the thermal management system of an embodiment of the present application;

[0058] Figure 5 A third thermal management mode diagram of the thermal management system of an embodiment of the present application;

[0059] Figure 6 This is a fourth thermal management mode diagram of the thermal management system of an embodiment of the present application;

[0060] Figure 7 This is a fifth thermal management mode diagram of the thermal management system of the embodiment of the present application;

[0061] Figure 8 This is a sixth thermal management mode diagram of the thermal management system of an embodiment of the present application;

[0062] Fig. 9 This is a seventh thermal management mode diagram of the thermal management system of the embodiment of the present application;

[0063] Fig.10 This is an eighth thermal management mode diagram of the thermal management system of the embodiment of the present application;

[0064] Fig.11 This is a ninth thermal management mode diagram of the thermal management system of an embodiment of the present application;

[0065] Fig.12 This is a tenth thermal management mode diagram of the thermal management system of an embodiment of the present application;

[0066] Fig.13 This is a diagram of the eleventh thermal management mode of the thermal management system according to an embodiment of the present application.

[0067] The reference numerals are:

[0068] 1. First heat exchanger; 2. Intermediate heat exchanger; 3. First pipeline; 4. Second pipeline; 5. External heat exchanger; 6. First three-way valve; 7. Second three-way valve; 8. First four-way valve; 9. First pump; 10. Second pump; 11. Motor; 12. Motor controller; 13. Battery assembly; 14. First two-way valve; 15. Second two-way valve; 16. Expansion water tank; 17. Compressor; 18. Second four-way valve; 19. Second heat exchanger; 20. First electronic expansion valve; 21. Second electronic expansion valve; 22. Gas-liquid separator; 23. Subcooler; 24. Flasher; 25. Third electronic expansion valve; 26. Fourth electronic expansion valve. DETAILED DESCRIPTION

[0069] See also Figures 1 to 13 As shown, according to an embodiment of the present application, the thermal management system includes an air-conditioning refrigerant circuit and a secondary coolant circuit, the air-conditioning refrigerant circuit includes a compressor 17, an enthalpy increasing device, a first heat exchanger 1 and an intermediate heat exchanger 2, the secondary coolant circuit includes a secondary coolant heat exchange pipeline, a regulating branch, a battery branch, a motor branch and an off-vehicle branch, the off-vehicle branch includes a first pipeline 3 and a second pipeline 4 connected in parallel, the secondary coolant heat exchange pipeline is connected to the first heat exchanger 1 for heat exchange, the first pipeline 3 is provided with an off-vehicle heat exchanger 5, the first pipeline 3 is provided with a first pipeline 4, and the secondary coolant heat exchange pipeline is connected to the first heat exchanger 1 for heat exchange. One end can be selectively connected to the first end of the first pipeline 3 or the second pipeline 4 through the first three-way valve 6, the second end of the refrigerant heat exchange pipeline can be selectively connected to the first end of the regulating branch or the motor branch through the second three-way valve 7, the second ends of the regulating branch, the battery branch, the motor branch and the vehicle external branch are connected through the first four-way valve 8, the regulating branch is connected to the battery branch through the heat exchange branch, the heat exchange branch is connected to the intermediate heat exchanger 2 for heat exchange, and the enthalpy increasing device is connected to the air supply port of the compressor 17 through the air supply pipeline. The above-mentioned compressor is, for example, a variable frequency compressor, which can adjust the refrigerant flow in the refrigerant circuit in real time, thereby controlling the output of cooling capacity or heating capacity.

[0070] The thermal management system of the present application can integrate the air-conditioning system, the battery thermal management system and the drive motor cooling system into a complete vehicle thermal management system, realize the temperature control of the vehicle compartment, battery components, motors, etc., make full use of and reasonably distribute the heat of each part, so that the operating temperature of the battery system and the motor system is maintained within the operating temperature range, the vehicle heat distribution is more efficient, the energy utilization is more reasonable, and the thermal management of the whole vehicle can be effectively realized, the energy utilization rate of the whole vehicle is improved, and the cruising range is increased.

[0071] The present application adopts a two-stage compression jet enthalpy increase system to improve the capacity output of the heat pump under overload conditions, reduce dependence on compressor displacement, reduce system costs, and improve the operating temperature range and adaptability to working conditions.

[0072] In this embodiment, the coolant circuit is divided into two modes, namely phase change mode and non-phase change mode. The phase change mode refers to the battery branch coolant and the air conditioning refrigerant exchanging heat through the intermediate heat exchanger 2, and the coolant further cools and heats the battery assembly 13, that is, the battery branch and the motor branch are not connected; the non-phase change heat exchange mode is to connect the battery branch coolant and the motor branch coolant in series, and the coolant exchanges heat at the first heat exchanger 1 in the air conditioning system or the external heat exchanger 5 to adjust the temperature of the coolant, and further adjust the temperature of the battery and the motor system. The phase change heat exchange mode responds to the battery thermal management in severe weather, improves the battery cooling efficiency or heating efficiency, and improves the battery charging and discharging efficiency; at the same time, when the phase change cooling system fails in severe weather, the non-phase change heat exchange cycle is started to maintain the battery temperature within a reasonable range, and improve the safety and reliability of the battery; the non-phase change heat exchange mode responds to the battery thermal management in transition seasons. The transition seasons here mainly refer to spring and autumn.

[0073] The air-conditioning refrigerant circuit and the coolant circuit in this embodiment cooperate with each other to form a variety of circulation circuits, which can cover the whole vehicle's thermal management mode throughout the year. It not only realizes the dual management of battery thermal management throughout the year, but also realizes waste heat recovery when heating the cabin in winter, and fully utilizes the heat dissipation of the heat source motor system to heat the battery assembly 13 and the cabin, reducing the power consumption of the air-conditioning system; when the battery generates a lot of heat, the heat dissipation of the battery assembly 13 can also be fully utilized to heat the cabin.

[0074] The enthalpy increasing device is arranged on the pipeline between the first heat exchanger 1 and the intermediate heat exchanger 2 , and a third electronic expansion valve 25 is arranged on the pipeline between the enthalpy increasing device and the first heat exchanger 1 .

[0075] In one embodiment, the enthalpy increasing device includes a subcooler 23, a fourth electronic expansion valve 26 is provided on the inlet pipe of the subcooler 23, and an outlet pipe of the subcooler 23 is connected to the air supply pipe.

[0076] In another embodiment, the enthalpy increasing device includes a flash generator 24, and the gas outlet of the flash generator 24 is connected to the gas supplement pipeline.

[0077] When the system uses the subcooler 23, there is a heat exchange temperature difference, the efficiency is lower than that of the flash igniter 24, the cost is relatively high, but the reliability is good; when the system uses the flash igniter 24, the efficiency is relatively high and the cost is low, but the liquid level is easy to shake during the driving of the car, resulting in the replenishment of gas with liquid, so the reliability is relatively low. When selecting the enthalpy increase device, comprehensive consideration can be given according to the actual situation, so that the system's working energy efficiency can be guaranteed while taking into account the cost.

[0078] The regulating branch is provided with a first pump 9, and the heat exchange branch is connected to the pipeline between the second three-way valve 7 and the first pump 9. In this embodiment, by adding the first pump 9, a coolant circulation motor mechanism can be added to the regulating branch, and the first pump 9 is used to provide circulation power for the coolant in the regulating branch.

[0079] The motor branch is provided with a motor controller 12 and / or a motor 11, and a second pump 10 is provided on the pipeline connecting the motor controller 12 and / or the motor 11 and the first four-way valve 8. In this embodiment, the motor controller 12 and the motor 11 are arranged in series on the motor branch, and the second pump 10 is located on the motor branch to provide circulation power for the coolant located on the motor branch.

[0080] The first pump 9 and the second pump 10 are, for example, variable speed pumps, so that the flow rate of the brine can be accurately controlled.

[0081] A battery assembly 13 is arranged on the battery branch, the heat exchange branch is connected to the end of the battery assembly 13 away from the first four-way valve 8, and a first two-way valve 14 is arranged on the pipeline connecting the end of the battery assembly 13 away from the first four-way valve 8 and the second three-way valve 7; and / or a second two-way valve 15 is arranged on the heat exchange branch.

[0082] By providing the first two-way valve 14 on the battery branch, the connection state between the battery branch and the motor branch can be adjusted by controlling the on-off of the first two-way valve 14, thereby adjusting the coolant flow path.

[0083] By arranging the second two-way valve 15 on the heat exchange branch, the connection state between the heat exchange branch and the battery branch can be adjusted by controlling the on-off of the second two-way valve 15, thereby adjusting the heat exchange mode of the battery branch. The first two-way valve 14 and the second two-way valve 15 are both solenoid valves.

[0084] The off-vehicle branch also includes an expansion water tank 16. After the first pipeline 3 and the second pipeline 4 are connected in parallel, they are connected to the first four-way valve 8. The expansion water tank 16 is arranged on the pipeline between the parallel pipeline and the first four-way valve 8. The expansion water tank 16 can improve the stability of the brine in the brine circuit, stabilize the system pressure, and improve the stability of system operation.

[0085] The air conditioning refrigerant circuit also includes a second four-way valve 18, and the compressor 17, the first heat exchanger 1 and the intermediate heat exchanger 2 are connected to the second four-way valve 18. The second four-way valve 18 is used to achieve the refrigerant flow reversal regulation of the air conditioning refrigerant circuit, thereby achieving the conversion of the cooling and heating working conditions of the air conditioning refrigerant circuit.

[0086] The air conditioning refrigerant circuit also includes a second heat exchanger 19, which is connected in parallel with the intermediate heat exchanger 2. A first electronic expansion valve 20 is provided on the branch where the second heat exchanger 19 is located, and a second electronic expansion valve 21 is provided on the branch where the intermediate heat exchanger 2 is located. The first electronic expansion valve 20 can control whether the second heat exchanger 19 works or not, and the second electronic expansion valve 21 can control whether the intermediate heat exchanger 2 works or not. By providing the first electronic expansion valve 20 and the second electronic expansion valve 21, the working state of the intermediate heat exchanger 2 or the second heat exchanger 19 can be adjusted without affecting the work of other branches.

[0087] In this embodiment, the first heat exchanger 1 is an outdoor heat exchanger of the air-conditioning refrigerant circuit, and the second heat exchanger 19 is an indoor heat exchanger of the air-conditioning refrigerant circuit. The air-conditioning refrigerant circuit mainly realizes the function of regulating the temperature in the vehicle compartment through the second heat exchanger 19.

[0088] A gas-liquid separator 22 is provided at the suction end of the compressor 17 .

[0089] When the air-conditioning refrigerant circuit is in a cooling state, the refrigerant flow direction in the intermediate heat exchanger 2 is the same as the coolant flow direction. When the air-conditioning refrigerant circuit is in a heating state, the refrigerant flow direction in the intermediate heat exchanger 2 is opposite to the coolant flow direction. This enables the refrigerant flow direction and the coolant flow direction to match the operating conditions of the air-conditioning refrigerant circuit, thereby effectively improving the heat exchange efficiency between the refrigerant and the coolant.

[0090] The above-mentioned coolant is, for example, water.

[0091] According to an embodiment of the present application, an electric vehicle includes a thermal management system, which is the thermal management system described above.

[0092] See also Figures 3 to 13 As shown, according to an embodiment of the present application, the thermal management method of the thermal management system includes: selecting a thermal management mode; and controlling the thermal management system according to the selected thermal management mode.

[0093] The present application can select a suitable thermal management mode according to the relationship between the battery temperature and the preset battery temperature or the season, so that the heat of the car, battery and motor can be managed in a unified manner, and the heat can be redistributed and adjusted according to the different working conditions, so as to achieve complementary utilization of heat, achieve waste heat utilization, precise temperature control, and improve the efficiency of the vehicle thermal management system. The system of the present application is described below by taking the enthalpy increase device including the supercooler 23 as an example.

[0094] For the air conditioning refrigerant circuit, when it is in cooling mode, starting from the air intake port of the compressor 17, the refrigerant flows as follows: compressor 17 → second four-way valve 18 → first heat exchanger 1 → third electronic expansion valve 25 → (fourth electronic expansion valve 26 → subcooler 23 → air supply port of compressor 17) subcooler 23 → first electronic expansion valve 20 and second electronic expansion valve 21 → second heat exchanger 19 and intermediate heat exchanger 2 → second four-way valve 18 → gas-liquid separator 22 → air intake port of compressor 17.

[0095] When the air-conditioning refrigerant circuit is in a cooling state, the first electronic expansion valve 20 can be closed so that the second heat exchanger 19 does not participate in the heat exchange work and only the intermediate heat exchanger 2 works.

[0096] When the air conditioning refrigerant circuit is in cooling mode, starting from the air intake port of the compressor 17, the refrigerant flows as follows: compressor 17 → second four-way valve 18 → second heat exchanger 19 and intermediate heat exchanger 2 → first electronic expansion valve 20 and second electronic expansion valve 21 → subcooler 23 → (fourth electronic expansion valve 26 → subcooler 23 → air supply port of compressor 17) third electronic expansion valve 25 → first heat exchanger 1 → second four-way valve 18 → gas-liquid separator 22 → air intake port of compressor 17.

[0097] When the air-conditioning refrigerant circuit is in the heating condition, the openings of the first electronic expansion valve 20 and the second electronic expansion valve 21 can be controlled so that the second heat exchanger 19 and the intermediate heat exchanger 2 do not work simultaneously.

[0098] In addition, the air conditioning refrigerant circuit can also be in a shutdown state, so that the first heat exchanger 1, the second heat exchanger 19 and the intermediate heat exchanger 2 do not exchange heat.

[0099] For the refrigerant circuit, it can be divided into phase change heat transfer mode and non-phase change heat transfer mode.

[0100] The phase change heat transfer mode is divided into two loops, namely the inner loop and the outer loop. The inner loop performs thermal management on the battery assembly 13, with the inlet of the first pump 9 as the starting point, and the coolant flows in the direction of the first pump 9 → the first four-way valve 8 → the battery assembly 13 → the second two-way valve 15 → the intermediate heat exchanger 2 → the first pump 9; the outer loop performs thermal management on the motor system, with the inlet of the second pump 10 as the starting point, and the coolant flows in the direction of the second pump 10 → the first four-way valve 8 → the expansion water tank 16 → the external heat exchanger 5 (or bypass) → the first three-way valve 6 → the first heat exchanger 1 → the second three-way valve 7 → the motor controller 12 → the motor 11 → the second pump 10. (such as Figure 3 , Figure 4 , Figure 5 , Figure 6 , Figure 7 , Figure 8 )

[0101] The non-phase-change heat transfer mode connects the battery and the motor system in series, that is, the intermediate heat exchanger 2 does not work, the first four-way valve 8 and the second three-way valve 7 are reversed, and the difference between the battery temperature and the motor system temperature is used to utilize the waste heat. For the purpose of heating the battery, with the inlet of the first pump 9 as the starting point, the flow direction of the refrigerant in the non-phase-change heat transfer mode is the first pump 9 → the first four-way valve 8 → the expansion tank 16 off-vehicle heat exchanger 5 (or bypass) → the first three-way valve 6 → the first heat exchanger 1 → the second three-way valve 7 → the motor controller 12 → the motor 11 → the second pump 10 → the first four-way valve 8 → the battery assembly 13 → the second two-way valve 15 → the intermediate heat exchanger 2 → the first pump 9, as shown in FIG. Fig. 9 and Fig.13 For the purpose of cooling the battery, with the inlet of the first pump 9 as the starting point, the flow direction of the coolant in the non-phase-change heat transfer mode is the first pump 9 → the first four-way valve 8 → the battery assembly 13 → the solenoid valve 9a → the motor controller 12 → the motor 11 → the second pump 10 → the first four-way valve 8 → the expansion water tank 16 → the external heat exchanger 5 (or bypass) → the first three-way valve 6 → the first heat exchanger 1 → the second three-way valve 7 → the first pump 9, as shown in FIG. Fig.10 , Fig.11 and Fig.12 .

[0102] The air conditioning refrigerant circuit and the secondary refrigerant circuit cooperate with each other. There are 11 circulation circuits in total, covering the vehicle's year-round thermal management mode. The following table gives Figure 3 — Fig.13 The corresponding 11 circulation loops are applicable to the thermal management mode of the whole vehicle.

[0103] Table 1 Temperature control mode of thermal management system of pure electric vehicle

[0104]

[0105] — represents not working, no cooling or heating demand; H represents heating demand; C represents cooling demand.

[0106] Some thermal management modes in the table have two or more cycle solutions, such as the transition season HCC corresponding to Fig.10 The eighth thermal management mode and Fig.11 The ninth thermal management mode is switched according to the heating demand of the cabin. For example, if the cabin heating demand is large, in addition to the waste heat from the battery and motor system, the heat source outside the vehicle is also required to provide heat, that is, select Fig.10 The eighth thermal management mode; if the cabin heating demand is small, select Fig.11 The ninth thermal management mode does not require heating from an external heat exchanger. Instead, the refrigerant recovers waste heat from the battery and motor system in the first heat exchanger 1 and heats the cabin through compression.

[0107] In addition, some cycle schemes in the table correspond to two or more thermal management modes, such as Fig.10 The second thermal management mode corresponds to the thermal management mode winter heating HHC and the thermal management mode winter preheating HH—. The difference between the two thermal management modes is that the motor system does not work and there is no cooling demand. For the thermal management mode winter heating HHC, the heat source of the air conditioning refrigerant circuit is the heat dissipation of the outdoor heat exchanger and the motor system, that is, the refrigerant in the first heat exchanger 1 absorbs the heat absorbed by the coolant from the outdoor heat exchanger 5 and the motor system, recovers the waste heat, and is compressed by the compressor to heat the car and the battery to meet the heating demand. For the thermal management mode winter preheating HH—, the heat source of the air conditioning refrigerant circuit is only the outdoor heat exchanger, that is, the refrigerant in the first heat exchanger 1 absorbs the heat absorbed by the coolant from the outdoor heat exchanger 5, and is compressed by the compressor to heat the car and the battery to meet the heating demand.

[0108] The control process of each management mode of this application is described below:

[0109] See also Figure 3 As shown, in the first thermal management mode of the present embodiment, the steps of controlling the thermal management system according to the selected thermal management mode include: controlling the air-conditioning refrigerant circuit to be in cooling mode; controlling the first three-way valve 6 to be connected to the first pipeline 3, controlling the second three-way valve 7 to be connected to the motor branch, controlling the heat exchange branch to be connected to the battery branch, controlling the battery branch to be disconnected from the motor branch, controlling the regulating branch to be connected to the battery branch, and controlling the motor branch to be connected to the branch outside the vehicle.

[0110] See also Figure 4 As shown, in the second thermal management mode of the present embodiment, the steps of controlling the thermal management system according to the selected thermal management mode include: controlling the air-conditioning refrigerant circuit to be in the heating mode; controlling the first three-way valve 6 to be connected to the first pipeline 3, controlling the second three-way valve 7 to be connected to the motor branch, controlling the heat exchange branch to be connected to the battery branch, controlling the battery branch to be disconnected from the motor branch, controlling the regulating branch to be connected to the battery branch, and controlling the motor branch to be connected to the branch outside the vehicle.

[0111] See also Figure 5 As shown, in the third thermal management mode of the present embodiment, the steps of controlling the thermal management system according to the selected thermal management mode include: controlling the air-conditioning refrigerant circuit to be in cooling mode, controlling the first electronic expansion valve 20 to be closed; controlling the first three-way valve 6 to be connected with the first pipeline 3, controlling the second three-way valve 7 to be connected with the motor branch, controlling the heat exchange branch to be connected with the battery branch, controlling the battery branch to be disconnected from the motor branch, controlling the adjustment branch to be connected with the battery branch, and controlling the motor branch to be connected with the branch outside the vehicle.

[0112] See also Figure 6As shown, in the fourth thermal management mode of the present embodiment, the steps of controlling the thermal management system according to the selected thermal management mode include: controlling the air-conditioning refrigerant circuit to be in heating mode, controlling the first electronic expansion valve 20 to be closed; controlling the first three-way valve 6 to be connected with the first pipeline 3, controlling the second three-way valve 7 to be connected with the motor branch, controlling the heat exchange branch to be connected with the battery branch, controlling the battery branch to be disconnected from the motor branch, controlling the adjustment branch to be connected with the battery branch, and controlling the motor branch to be connected with the branch outside the vehicle.

[0113] See also Figure 7 As shown, in the fifth thermal management mode of the present embodiment, the steps of controlling the thermal management system according to the selected thermal management mode include: controlling the air-conditioning refrigerant circuit to be in heating mode, controlling the first electronic expansion valve 20 to be closed; controlling the first three-way valve 6 to be connected with the second pipeline 4, controlling the second three-way valve 7 to be connected with the motor branch, controlling the heat exchange branch to be connected with the battery branch, controlling the battery branch to be disconnected from the motor branch, controlling the adjustment branch to be connected with the battery branch, and controlling the motor branch to be connected with the branch outside the vehicle.

[0114] See also Figure 8 As shown, in the sixth thermal management mode of the present embodiment, the steps of controlling the thermal management system according to the selected thermal management mode include: controlling the air-conditioning refrigerant circuit to be in heating mode; controlling the first three-way valve 6 to be connected with the second pipeline 4, controlling the second three-way valve 7 to be connected with the motor branch, controlling the heat exchange branch to be connected with the battery branch, controlling the battery branch to be disconnected from the motor branch, controlling the regulating branch to be connected with the battery branch, and controlling the motor branch to be connected with the branch outside the vehicle.

[0115] See also Fig. 9 As shown, in the seventh thermal management mode of the present embodiment, the steps of controlling the thermal management system according to the selected thermal management mode include: controlling the air-conditioning refrigerant circuit to be in heating mode, controlling the second electronic expansion valve 21 to be closed; controlling the first three-way valve 6 to be connected with the first pipeline 3, controlling the second three-way valve 7 to be connected with the motor branch, controlling the heat exchange branch to be connected with the battery branch, controlling the battery branch to be disconnected from the motor branch, controlling the regulating branch to be connected with the branch outside the vehicle, and controlling the motor branch to be connected with the battery branch.

[0116] See also Fig.10 As shown, in the eighth thermal management mode of the present embodiment, the steps of controlling the thermal management system according to the selected thermal management mode include: controlling the air-conditioning refrigerant circuit to be in heating mode, controlling the second electronic expansion valve 21 to be closed; controlling the first three-way valve 6 to be connected to the first pipeline 3, controlling the second three-way valve 7 to be connected to the regulating branch, controlling the heat exchange branch to be disconnected from the battery branch, controlling the battery branch to be connected to the motor branch, controlling the regulating branch to be connected to the battery branch, and controlling the motor branch to be connected to the branch outside the vehicle.

[0117] See also Fig.11 As shown, in the ninth thermal management mode of the present embodiment, the steps of controlling the thermal management system according to the selected thermal management mode include: controlling the air-conditioning refrigerant circuit to be in heating mode, controlling the second electronic expansion valve 21 to be closed; controlling the first three-way valve 6 to be connected with the second pipeline 4, controlling the second three-way valve 7 to be connected with the regulating branch, controlling the heat exchange branch to be disconnected from the battery branch, controlling the battery branch to be connected with the motor branch, controlling the regulating branch to be connected with the battery branch, and controlling the motor branch to be connected with the branch outside the vehicle.

[0118] See also Fig.12 As shown, in the tenth thermal management mode of the present embodiment, the steps of controlling the thermal management system according to the selected thermal management mode include: controlling the air-conditioning refrigerant circuit to be in a shutdown state; controlling the first three-way valve 6 to be connected to the first pipeline 3, controlling the second three-way valve 7 to be connected to the regulating branch, controlling the heat exchange branch to be disconnected from the battery branch, controlling the battery branch to be connected to the motor branch, controlling the regulating branch to be connected to the battery branch, and controlling the motor branch to be connected to the branch outside the vehicle.

[0119] See also Fig.13 As shown, in the eleventh thermal management mode of the present embodiment, the steps of controlling the thermal management system according to the selected thermal management mode include: controlling the air-conditioning refrigerant circuit to be in a shutdown state; controlling the first three-way valve 6 to be connected with the second pipeline 4, controlling the second three-way valve 7 to be connected with the motor branch, controlling the heat exchange branch to be connected with the battery branch, controlling the battery branch to be disconnected from the motor branch, controlling the adjustment branch to be connected with the branch outside the vehicle, and controlling the motor branch to be connected with the battery branch.

[0120] It is easy for those skilled in the art to understand that, under the premise of no conflict, the above-mentioned advantageous methods can be freely combined and superimposed.

[0121] The above are only preferred embodiments of the present application and are not intended to limit the present application. Any modifications, equivalent replacements and improvements made within the spirit and principles of the present application shall be included in the protection scope of the present application. The above are only preferred implementations of the present application. It should be pointed out that for ordinary technicians in this technical field, several improvements and variations can be made without departing from the technical principles of the present application, and these improvements and variations should also be regarded as the protection scope of the present application.

Claims

1. A thermal management system, characterized in that: The invention comprises an air conditioning refrigerant circuit and a secondary refrigerant circuit, wherein the air conditioning refrigerant circuit comprises a compressor (17), an enthalpy increasing device, a first heat exchanger (1) and an intermediate heat exchanger (2), wherein the secondary refrigerant circuit comprises a secondary refrigerant heat exchange pipeline, a regulating branch, a battery branch, a motor branch and an off-vehicle branch, wherein the off-vehicle branch comprises a first pipeline (3) and a second pipeline (4) connected in parallel, wherein the secondary refrigerant heat exchange pipeline is connected to the first heat exchanger (1) for heat exchange, wherein the first pipeline (3) is provided with an off-vehicle heat exchanger (5), and wherein the first end of the secondary refrigerant heat exchange pipeline can be connected to the first heat exchanger (1) via a first three-way valve (6). The first end of the second pipeline (3) or the second pipeline (4) is selectively connected to the first end of the first pipeline (3) or the second pipeline (4); the second end of the coolant heat exchange pipeline can be selectively connected to the first end of the regulating branch or the motor branch through a second three-way valve (7); the second ends of the regulating branch, the battery branch, the motor branch and the off-vehicle branch are connected through a first four-way valve (8); the regulating branch is connected to the battery branch through a heat exchange branch; the heat exchange branch is connected to the intermediate heat exchanger (2) in heat exchange; and the enthalpy increasing device is connected to the air supply port of the compressor through an air supply pipeline; A battery assembly (13) is arranged on the battery branch, the heat exchange branch is connected to an end of the battery assembly (13) away from the first four-way valve (8), a first two-way valve (14) is arranged on a pipeline connecting an end of the battery assembly (13) away from the first four-way valve (8) and the second three-way valve (7); and / or a second two-way valve (15) is arranged on the heat exchange branch.

2. The thermal management system according to claim 1, characterized in that: The regulating branch is provided with a first pump (9), and the heat exchange branch is connected to the pipeline between the second three-way valve (7) and the first pump (9).

3. The thermal management system according to claim 1, characterized in that: The motor branch is provided with a motor controller (12) and / or a motor (11), and a second pump (10) is provided on a pipeline connecting the motor controller (12) and / or the motor (11) and the first four-way valve (8).

4. The thermal management system according to claim 1, characterized in that: The off-vehicle branch further comprises an expansion water tank (16); the first pipeline (3) and the second pipeline (4) are connected in parallel and then connected to the first four-way valve (8); the expansion water tank (16) is arranged on the pipeline between the parallel pipeline and the first four-way valve (8).

5. The thermal management system according to claim 1, characterized in that: The air-conditioning refrigerant circuit further comprises a second four-way valve (18), and the compressor (17), the first heat exchanger (1) and the intermediate heat exchanger (2) are connected to the second four-way valve (18).

6. The thermal management system according to claim 5, characterized in that: The air-conditioning refrigerant circuit also includes a second heat exchanger (19), the second heat exchanger (19) is connected in parallel with the intermediate heat exchanger (2), a first electronic expansion valve (20) is provided on the branch where the second heat exchanger (19) is located, and a second electronic expansion valve (21) is provided on the branch where the intermediate heat exchanger (2) is located.

7. The thermal management system according to claim 5, characterized in that: A gas-liquid separator (22) is provided at the air intake end of the compressor (17).

8. The thermal management system according to claim 1, characterized in that: When the air-conditioning refrigerant circuit is in a cooling state, the refrigerant flow direction in the intermediate heat exchanger (2) is the same as the coolant flow direction; when the air-conditioning refrigerant circuit is in a heating state, the refrigerant flow direction in the intermediate heat exchanger (2) is opposite to the coolant flow direction.

9. The thermal management system according to any one of claims 1 to 8, characterized in that: The enthalpy increasing device is arranged on the pipeline between the first heat exchanger (1) and the intermediate heat exchanger (2), and a third electronic expansion valve (25) is arranged on the pipeline between the enthalpy increasing device and the first heat exchanger (1).

10. The thermal management system according to claim 9, characterized in that: The enthalpy increasing device comprises a subcooler (23), a fourth electronic expansion valve (26) is arranged on the inlet pipe of the subcooler (23), and the outlet pipe of the subcooler (23) is connected to the air supply pipeline; or, the enthalpy increasing device comprises a flasher (24), and the air outlet of the flasher (24) is connected to the air supply pipeline.

11. An electric vehicle, comprising a thermal management system, characterized in that: The thermal management system is the thermal management system according to any one of claims 1 to 10.

12. A thermal management method for a thermal management system according to any one of claims 1 to 10, characterized in that: include: Select the thermal management mode; The thermal management system is controlled according to the selected thermal management mode.

13. The thermal management method of the thermal management system according to claim 12, characterized in that: The steps of controlling the thermal management system according to the selected thermal management mode include: Control the air conditioning refrigerant circuit to be in cooling mode; The first three-way valve (6) is controlled to be connected to the first pipeline (3), the second three-way valve (7) is controlled to be connected to the motor branch, the heat exchange branch is controlled to be connected to the battery branch, the battery branch is controlled to be disconnected from the motor branch, the regulating branch is controlled to be connected to the battery branch, and the motor branch is controlled to be connected to the off-vehicle branch.

14. The thermal management method of the thermal management system according to claim 12, characterized in that: The steps of controlling the thermal management system according to the selected thermal management mode include: Control the air conditioning refrigerant circuit to be in heating mode; The first three-way valve (6) is controlled to be connected to the first pipeline (3), the second three-way valve (7) is controlled to be connected to the motor branch, the heat exchange branch is controlled to be connected to the battery branch, the battery branch is controlled to be disconnected from the motor branch, the regulating branch is controlled to be connected to the battery branch, and the motor branch is controlled to be connected to the off-vehicle branch.

15. The thermal management method of the thermal management system according to claim 12, characterized in that: The steps of controlling the thermal management system according to the selected thermal management mode include: Controlling the air-conditioning refrigerant circuit to be in a cooling mode, and controlling the first electronic expansion valve (20) to be closed; The first three-way valve (6) is controlled to be connected to the first pipeline (3), the second three-way valve (7) is controlled to be connected to the motor branch, the heat exchange branch is controlled to be connected to the battery branch, the battery branch is controlled to be disconnected from the motor branch, the regulating branch is controlled to be connected to the battery branch, and the motor branch is controlled to be connected to the off-vehicle branch.

16. The thermal management method of the thermal management system according to claim 12, characterized in that: The steps of controlling the thermal management system according to the selected thermal management mode include: Controlling the air-conditioning refrigerant circuit to be in a heating mode, and controlling the first electronic expansion valve (20) to be closed; The first three-way valve (6) is controlled to be connected to the first pipeline (3), the second three-way valve (7) is controlled to be connected to the motor branch, the heat exchange branch is controlled to be connected to the battery branch, the battery branch is controlled to be disconnected from the motor branch, the regulating branch is controlled to be connected to the battery branch, and the motor branch is controlled to be connected to the off-vehicle branch.

17. The thermal management method of a thermal management system according to claim 12, characterized in that: The steps of controlling the thermal management system according to the selected thermal management mode include: Controlling the air-conditioning refrigerant circuit to be in a heating mode, and controlling the first electronic expansion valve (20) to be closed; The first three-way valve (6) is controlled to be connected to the second pipeline (4), the second three-way valve (7) is controlled to be connected to the motor branch, the heat exchange branch is controlled to be connected to the battery branch, the battery branch is controlled to be disconnected from the motor branch, the regulating branch is controlled to be connected to the battery branch, and the motor branch is controlled to be connected to the vehicle external branch.

18. The thermal management method of a thermal management system according to claim 12, characterized in that: The steps of controlling the thermal management system according to the selected thermal management mode include: Control the air conditioning refrigerant circuit to be in heating mode; The first three-way valve (6) is controlled to be connected to the second pipeline (4), the second three-way valve (7) is controlled to be connected to the motor branch, the heat exchange branch is controlled to be connected to the battery branch, the battery branch is controlled to be disconnected from the motor branch, the regulating branch is controlled to be connected to the battery branch, and the motor branch is controlled to be connected to the vehicle external branch.

19. The thermal management method of a thermal management system according to claim 12, characterized in that: The steps of controlling the thermal management system according to the selected thermal management mode include: Controlling the air-conditioning refrigerant circuit to be in a heating mode, and controlling the second electronic expansion valve (21) to be closed; The first three-way valve (6) is controlled to be connected to the first pipeline (3), the second three-way valve (7) is controlled to be connected to the motor branch, the heat exchange branch is controlled to be connected to the battery branch, the battery branch is controlled to be disconnected from the motor branch, the regulating branch is controlled to be connected to the off-vehicle branch, and the motor branch is controlled to be connected to the battery branch.

20. The thermal management method of a thermal management system according to claim 12, characterized in that: The steps of controlling the thermal management system according to the selected thermal management mode include: Controlling the air-conditioning refrigerant circuit to be in a heating mode, and controlling the second electronic expansion valve (21) to be closed; The first three-way valve (6) is controlled to be connected to the first pipeline (3), the second three-way valve (7) is controlled to be connected to the regulating branch, the heat exchange branch is controlled to be disconnected from the battery branch, the battery branch is controlled to be connected to the motor branch, the regulating branch is controlled to be connected to the battery branch, and the motor branch is controlled to be connected to the off-vehicle branch.

21. The thermal management method of a thermal management system according to claim 12, characterized in that: The steps of controlling the thermal management system according to the selected thermal management mode include: Controlling the air-conditioning refrigerant circuit to be in a heating mode, and controlling the second electronic expansion valve (21) to be closed; The first three-way valve (6) is controlled to be connected to the second pipeline (4), the second three-way valve (7) is controlled to be connected to the regulating branch, the heat exchange branch is controlled to be disconnected from the battery branch, the battery branch is controlled to be connected to the motor branch, the regulating branch is controlled to be connected to the battery branch, and the motor branch is controlled to be connected to the branch outside the vehicle.

22. The thermal management method of the thermal management system according to claim 12, characterized in that: The steps of controlling the thermal management system according to the selected thermal management mode include: Control the air conditioning refrigerant circuit to be in shutdown state; The first three-way valve (6) is controlled to be connected to the first pipeline (3), the second three-way valve (7) is controlled to be connected to the regulating branch, the heat exchange branch is controlled to be disconnected from the battery branch, the battery branch is controlled to be connected to the motor branch, the regulating branch is controlled to be connected to the battery branch, and the motor branch is controlled to be connected to the off-vehicle branch.

23. The thermal management method of a thermal management system according to claim 12, characterized in that: The steps of controlling the thermal management system according to the selected thermal management mode include: Control the air conditioning refrigerant circuit to be in shutdown state; The first three-way valve (6) is controlled to be connected to the second pipeline (4), the second three-way valve (7) is controlled to be connected to the motor branch, the heat exchange branch is controlled to be connected to the battery branch, the battery branch is controlled to be disconnected from the motor branch, the regulating branch is controlled to be connected to the off-vehicle branch, and the motor branch is controlled to be connected to the battery branch.

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