An electric vehicle whole vehicle thermal management system and method

Abstract

The application discloses an electric vehicle whole vehicle thermal management system, comprising: a heat pump module, a motor and a driving unit thermal management module, a battery thermal management module and a cabin thermal management module; a water-cooled condenser 5 is arranged in the heat pump module; a total circulating liquid loop is formed between the motor and the driving unit thermal management module, the battery thermal management module, the cabin thermal management module and the water-cooled condenser 5; a plurality of isolation valve bodies are arranged on the total circulating liquid loop, and are used for disconnecting and connecting between at least two of the motor and the driving unit thermal management module, the battery thermal management module, the cabin thermal management module and the water-cooled condenser 5. The application can comprehensively utilize the heat energy of the whole vehicle, reduce the battery power attenuation and improve the operation efficiency of the whole vehicle.

Description

Technical Field

[0001] This invention belongs to the field of thermal management technology for electric vehicles, specifically relating to a thermal management system and method for an electric vehicle. Background Technology

[0002] The biggest pain points for electric vehicles, especially electric heavy-duty trucks, are the severe reduction in driving range under high and low temperature conditions and the significantly extended fast charging time. There are many conflicting issues related to battery heat dissipation, motor heat dissipation, drive unit heat dissipation, and cabin heating.

[0003] Firstly, in practice, a battery can discharge when its temperature is between -20℃ and 18℃. However, its capacity decreases when the temperature drops below 0℃. The ideal discharge temperature range for a battery is 18℃-36℃. Once the battery temperature falls below 18℃, it needs to be heated. The battery's heating film raises its temperature by consuming its own energy. While the battery has a large heat capacity, the theoretical efficiency of the heating film is 1. However, considering heat loss, the actual efficiency is less than 1. This results in a long heating time and a significant waste of battery energy. For example, heating a lithium battery pack in an electric heavy-duty truck from -15℃ to 18℃ consumes 30-40 kWh of energy, accounting for 10%-15% of the total capacity of the lithium battery pack.

[0004] Secondly, when the cabin of an electric heavy-duty truck needs heating and air supply, PTC heating is used, with a theoretical efficiency of 1 and a power consumption of 5kW·h-7kW·h.

[0005] Finally, lithium battery packs need to be limited in capacity, reserving at least 20% of the capacity to avoid irreversible capacity degradation caused by over-discharge of the lithium battery pack.

[0006] In summary, during driving, the cabin may need to be heated, and the lithium battery pack may also need to be heated. Therefore, very little of the stored energy is actually used for the motor and its drive unit for driving, which severely limits the driving range. Summary of the Invention

[0007] In view of this, the present invention provides a thermal management system and method for electric vehicles, which comprehensively utilizes the thermal energy of the vehicle to reduce battery capacity degradation and improve the overall operating efficiency of the vehicle.

[0008] This invention is achieved through the following technical solution:

[0009] An electric vehicle thermal management system includes: a heat pump module, a motor and its drive unit thermal management module, a battery thermal management module, and a cabin thermal management module;

[0010] The heat pump module is equipped with a water-cooled condenser and an evaporator. The evaporator is installed in the cabin and is used for cabin cooling.

[0011] A total circulating liquid loop is formed between the motor and its drive unit thermal management module, the battery thermal management module, the cabin thermal management module, and the water-cooled condenser; the total circulating liquid loop is equipped with several isolation valves for disconnecting and connecting at least two of the motor and its drive unit thermal management module, the battery thermal management module, the cabin thermal management module, and the water-cooled condenser;

[0012] The motor and its drive unit thermal management module is used to heat or cool the motor and its drive unit. The motor and its drive unit thermal management module is equipped with a second chiiller, and the water-cooled condenser can exchange heat with the second chiiller.

[0013] The battery thermal management module is used to heat or cool the battery. The battery thermal management module is equipped with a first chiller, and the water-cooled condenser can exchange heat with the first chiller.

[0014] A method for thermal management of an electric vehicle, and a thermal management system for an electric vehicle, including control of the vehicle's thermal management system under the following operating conditions:

[0015] Operating Condition 1: When the waste heat from the motor and its drive unit is directly supplied to the cabin for heating, the first and third reversing ports of the first three-way reversing valve are open, the second three-way reversing valve is closed, the first and third reversing ports of the third three-way reversing valve are open, the first and third reversing ports of the fourth three-way reversing valve are open, the first and third reversing ports of the fifth three-way reversing valve are open, at least one of the second reversing port and the second water circuit solenoid valve is closed, and the first, second, and third refrigerant circuit solenoid valves are all closed; the first water circuit solenoid valve is open, the first and second electronic expansion valves are both inactive, and the third water pump is started;

[0016] Operating Condition 2: When the waste heat from the motor and its drive unit is supplied to the cabin for heating via the heat pump, the second and third reversing ports of the first three-way reversing valve are open, the first and third reversing ports of the second three-way reversing valve are open, the first and second reversing ports of the third three-way reversing valve are open, the first and second reversing ports of the fourth three-way reversing valve are open, the first and second reversing ports of the fifth three-way reversing valve are open, the first refrigerant circuit solenoid valve is open, the second and third refrigerant circuit solenoid valves are both closed, the first water circuit solenoid valve is closed, the second water circuit solenoid valve is open, the first electronic expansion valve is not working, the second electronic expansion valve is working, the compressor is working, the third water pump is working, and the first water pump is not working.

[0017] Operating Condition 3: When the waste heat from the motor and its drive unit is directly supplied to the battery for heating, the first and third reversing ports of the first three-way reversing valve are open, the second three-way reversing valve is closed, the first and third reversing ports of the third three-way reversing valve are open, the first and second reversing ports of the fourth three-way reversing valve are open, the second reversing port of the fifth three-way reversing valve and at least one of the second water circuit solenoid valves are closed, the first, second, and third refrigerant circuit solenoid valves are all closed, the first water circuit solenoid valve is open, the first and second electronic expansion valves are all inactive, and the second water pump is turned on.

[0018] Operating Condition 4: When the waste heat from the motor and its drive unit is used to heat the battery through the heat pump, the second and third reversing ports of the first three-way reversing valve open, the first and third reversing ports of the second three-way reversing valve open, the third three-way reversing valve closes, the second and third reversing ports of the fourth three-way reversing valve open, the second and third reversing ports of the fifth three-way reversing valve open, the first refrigerant circuit solenoid valve opens, the second and third refrigerant circuit solenoid valves are both closed, the first water circuit solenoid valve closes, the second water circuit solenoid valve opens, the second electronic expansion valve operates, the first electronic expansion valve does not operate, and the compressor, the first water pump, and the second water pump operate.

[0019] Operating Condition 5: When the waste heat from the motor and its drive unit is directly supplied to the battery and cabin heating, the first and third reversing ports of the first three-way reversing valve are open, the first and third reversing ports of the second three-way reversing valve are open, the first and third reversing ports of the third three-way reversing valve are open, the first, second, and third reversing ports of the fourth three-way reversing valve are open, the first and third reversing ports of the fifth three-way reversing valve are open, the first, second, and third reversing ports of the reversing valve are all closed, the first water circuit solenoid valve is open, at least one of the second reversing port and the second water circuit solenoid valve is closed, the first and second electronic expansion valves are all inactive, and the third, second, and first water pumps are operational.

[0020] Operating Condition 6: When the waste heat from the motor and its drive unit simultaneously heats the battery and the cabin through the heat pump, the second and third reversing ports of the first three-way reversing valve are open, and at least one of the first reversing port of the first three-way reversing valve and the third reversing port of the third three-way reversing valve is closed; the first and third reversing ports of the second three-way reversing valve are open, the third reversing port of the fourth three-way reversing valve is open, and all three reversing ports of the fifth three-way reversing valve are open; the first refrigerant circuit solenoid valve is open, and all two refrigerant circuit solenoid valves are closed; the first water circuit solenoid valve is closed, and the second water circuit solenoid valve is open; the first electronic expansion valve is not working, the second electronic expansion valve is working, and the third, second, and first water pumps are all turned on.

[0021] Operating Condition 7: When the motor and its drive unit, and the waste heat from the battery are simultaneously supplied to the cabin for heating via the heat pump, the second and third reversing ports of the first three-way reversing valve are open, the first and third reversing ports of the second three-way reversing valve are open, the first and second reversing ports of the third three-way reversing valve are open, at least one of the third reversing port of the third three-way reversing valve and the first reversing port of the first three-way reversing valve is closed, the first and second reversing ports of the fourth three-way reversing valve are open, the first and second reversing ports of the fifth three-way reversing valve are open, the third reversing port is closed, the first refrigerant circuit solenoid valve is open, both the second and third refrigerant circuit solenoid valves are closed, the first water circuit solenoid valve is closed, the second water circuit solenoid valve is open, both the first and second electronic expansion valves are working, and the compressor, the third water pump, the second water pump, and the first water pump are all working.

[0022] Beneficial effects:

[0023] (1) The present invention provides a whole vehicle thermal management system for electric vehicles, which, except for the evaporator, can be integrated into a certain area of ​​the electric vehicle. In addition, the whole vehicle thermal management system can, on the one hand, use the water-cooled condenser of the heat pump module to cool the motor and its drive unit thermal management module, the battery thermal management module and the cabin thermal management module separately; on the other hand, a number of isolation valves are provided on the main circulating liquid circuit, which can realize the disconnection and connection between at least two of the motor and its drive unit thermal management module, the battery thermal management module, the cabin thermal management module and the water-cooled condenser, thereby realizing heat exchange between modules. For example, the heat generated by the battery and the electric drive and its drive unit can be used to heat the cabin directly or through the heat pump, or the waste heat of the motor and its drive unit can be used to heat the battery directly or through the heat pump, or the waste heat of the motor and its drive unit can be used to heat the battery and the cabin simultaneously, thereby improving the operating efficiency of the whole vehicle, making full use of thermal energy and electrical energy, increasing the driving range of the electric vehicle and making the electric vehicle operate safely.

[0024] (2) The electric vehicle thermal management system provided by the present invention can also cool the battery and electric drive through the air-cooled radiator, and can also introduce PTC to heat the battery and cabin at low temperatures to make up for the disadvantage of low heat pump efficiency at low temperatures.

[0025] (3) The present invention provides a thermal management system for an electric vehicle, wherein an air-cooled condenser, an air-cooled radiator, and a fan are arranged side by side. The fan is configured such that when it rotates in a preset direction, the air blown out flows sequentially through the air-cooled radiator and the air-cooled condenser, or the air flows sequentially through the air-cooled radiator and the air-cooled condenser and is then blown out by the fan. The air-cooled radiator and the air-cooled condenser share a single fan, which not only saves costs but also makes the thermal management system for the electric vehicle smaller in size.

[0026] (4) The present invention provides a whole vehicle thermal management system for electric vehicles. The battery thermal management module further includes a second expansion tank to replenish water to the second internal circulation liquid circuit. When the cooling demand of the battery is low, the second water pump can be used to draw water from the second expansion tank to cool the battery without activating the heat pump module, thereby reducing energy consumption.

[0027] (5) The present invention provides a thermal management system for an electric vehicle, comprising several temperature sensors and temperature and pressure sensors, which can accurately detect the temperature or temperature and pressure at corresponding locations, facilitating system optimization, energy saving, and fault early warning and diagnosis. Temperature sensors are installed both before and after the battery to ensure it operates within a safe temperature range, extending battery life and improving its performance.

[0028] (6) The present invention provides a whole vehicle thermal management method for electric vehicles, which utilizes several valve bodies to realize the flow of heat energy between various modules, which can reduce energy consumption under various working conditions, improve the operating efficiency of the whole vehicle, and has the advantages of high operating efficiency, high reliability and high safety. Attached Figure Description

[0029] Figure 1 This is a schematic diagram of the electric vehicle thermal management system provided in a specific embodiment of the present invention.

[0030] Figure 2 This is a schematic diagram showing the flow direction of refrigerant and circulating fluid when the cabin requires separate cooling.

[0031] Figure 3 This is a schematic diagram showing the flow direction of refrigerant and circulating fluid under the condition that the waste heat of the motor and its drive unit is directly supplied to the cabin for heating.

[0032] Figure 4 This is a schematic diagram showing the flow direction of refrigerant and circulating fluid when the waste heat of the motor and its drive unit is supplied to the cabin for heating via a heat pump.

[0033] Figure 5 This is a schematic diagram showing the flow direction of refrigerant and circulating fluid when the cabin requires PTC water heating.

[0034] Figure 6 This is a schematic diagram showing the flow direction of refrigerant and circulating fluid when the motor and its drive unit require air cooling.

[0035] Figure 7 This is a schematic diagram showing the flow direction of the refrigerant and circulating fluid when the battery requires air cooling.

[0036] Figure 8 This is a schematic diagram showing the flow direction of refrigerant and circulating fluid when the motor, its drive unit, and battery all require air cooling.

[0037] Figure 9This is a schematic diagram showing the flow direction of the refrigerant and circulating fluid when the battery requires separate cooling.

[0038] Figure 10 This is a schematic diagram showing the flow direction of refrigerant and circulating fluid under the condition that the waste heat of the motor and its drive unit is directly supplied to the battery for heating.

[0039] Figure 11 This is a schematic diagram showing the flow direction of refrigerant and circulating fluid when the waste heat of the motor and its drive unit is supplied to the battery via a heat pump.

[0040] Figure 12 This is a schematic diagram showing the flow direction of refrigerant and circulating fluid when the battery requires water heating PTC heating.

[0041] Figure 13 This is a schematic diagram showing the flow direction of refrigerant and circulating fluid when both the cabin and battery require cooling.

[0042] Figure 14 It is a schematic diagram showing the flow direction of refrigerant and circulating fluid under the conditions of direct supply of waste heat from the motor and its drive unit to the battery and cabin heating.

[0043] Figure 15 This is a schematic diagram showing the flow direction of refrigerant and circulating fluid when the waste heat of the motor and its drive unit is used by the heat pump to heat the battery and the cabin simultaneously.

[0044] Figure 16 This is a schematic diagram showing the flow direction of refrigerant and circulating fluid when the motor and its drive unit, battery waste heat, and heat pump are simultaneously supplied to the cabin for heating.

[0045] Among them, 1-compressor, 2-first temperature and pressure sensor, 3-first refrigerant circuit solenoid valve, 4-second refrigerant circuit solenoid valve, 5-water-cooled condenser, 6-air-cooled condenser, 7-first electronic expansion valve, 8-second temperature and pressure sensor, 9-third refrigerant circuit solenoid valve, 10-thermal expansion valve, 11-evaporator, 12-third water pump, 13-first PTC, 14-heater core, 15-second water circuit solenoid valve, 16-fifth three-way reversing valve, 1601-first reversing port V, 1602-second reversing port V, 1603-third reversing port V, 17-first chiiller, 18-fourth three-way reversing valve, 1801-first reversing port IV, 1802-second reversing port IV, 1803-third reversing port IV, 19-third three-way reversing valve, 1901-first reversing port IV Ⅲ, 1902-Second reversing port Ⅲ, 1903-Third reversing port Ⅲ, 20-Second expansion tank, 21-Second water pump, 22-Second PTC, 23-Second temperature sensor, 24-Battery, 25-Third temperature sensor, 26-Second electronic expansion valve, 27-Third temperature and pressure sensor, 28-Second chiller, 29-Motor and its drive unit, 30-First temperature sensor, 31-First three-way reversing valve, 3101-First reversing port Ⅰ, 3102-Second reversing port Ⅰ, 3103-Third reversing port Ⅰ, 32-First water pump, 33-Second three-way reversing valve, 3301-First reversing port Ⅱ, 3302-Second reversing port Ⅱ, 3303-Third reversing port Ⅱ, 34-Air-cooled radiator, 35-First water circuit solenoid valve, 36-First expansion tank. Detailed Implementation

[0046] The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0047] Example 1:

[0048] This embodiment provides a thermal management system for an electric vehicle. The electric vehicle includes a battery, a cabin, a motor, and its drive unit. See attached diagram. Figure 1 The vehicle thermal management system includes: a heat pump module, a motor and its drive unit thermal management module, a battery thermal management module, and a cabin thermal management module;

[0049] The heat pump module is equipped with a water-cooled condenser 5 and an evaporator 11. The evaporator 11 is installed in the cabin and is used for cabin cooling.

[0050] A total circulating liquid loop is formed between the thermal management module of the motor and its drive unit, the thermal management module of the battery, the thermal management module of the cabin, and the water-cooled condenser 5; a number of isolation valves are provided on the total circulating liquid loop for disconnection and connection between at least two of the thermal management modules of the motor and its drive unit, the thermal management module of the battery, the thermal management module of the cabin, and the water-cooled condenser 5.

[0051] The motor and its drive unit thermal management module is used to heat or cool the motor and its drive unit 29. The motor and its drive unit thermal management module is equipped with a second chiiller 28. The water-cooled condenser 5 can exchange heat with the second chiiller 28.

[0052] The battery thermal management module is used to heat or cool the battery 24. The battery thermal management module is equipped with a first chiller 17, and the water-cooled condenser 5 can exchange heat with the first chiller 17.

[0053] This embodiment provides a vehicle thermal management system for electric vehicles. On one hand, the water-cooled condenser 5 of the heat pump module can be used to individually cool the thermal management modules of the motor and its drive unit, the battery thermal management module, and the cabin thermal management module. On the other hand, several isolation valves are provided on the main circulating liquid circuit, which can realize the disconnection and connection between at least two of the thermal management modules of the motor and its drive unit, the battery thermal management module, the cabin thermal management module, and the water-cooled condenser 5, thereby realizing heat exchange between modules, improving heat utilization, reducing battery power decay, and improving the overall vehicle operating efficiency.

[0054] It should be noted that the heat pump module contains refrigerant, while the cabin thermal management module, the motor and its drive unit thermal management module, and the battery thermal management module all contain circulating fluid. The freezing temperature of the circulating fluid is relatively low. Generally speaking, the freezing temperature of the circulating fluid is required to be below -30°C. The type of circulating fluid is selected according to actual needs, and this embodiment does not limit it.

[0055] In this embodiment, all components of the electric vehicle thermal management system (except for the evaporator 11) are integrated into one area, which can be installed outside the vehicle body or in other places, making it convenient for assembly, maintenance and operation.

[0056] The heat pump module also includes a compressor 1, an air-cooled condenser 6, a thermal expansion valve 10, a first electronic expansion valve 7, and a second electronic expansion valve 26; the compressor 1, the water-cooled condenser 5, the thermal expansion valve 10, and the evaporator 11 are connected in series to form a loop through refrigerant piping; the air-cooled condenser 6 and the water-cooled condenser 5 are connected in parallel; the first electronic expansion valve 7 is located on the refrigerant piping between the heat pump module and the first chiller 17, and is located upstream of the first chiller 17; the second electronic expansion valve 26 is located on the refrigerant piping between the heat pump module and the second chiller 28, and is located upstream of the second chiller 28;

[0057] Specifically, the first chiller 17 is connected to the heat pump module through two refrigerant lines. The first electronic expansion valve 7 is installed on one refrigerant line, and one end is connected to the downstream refrigerant line of the water-cooled condenser 5 and the air-cooled condenser 6, and the other end is connected to the first chiller 17. One end of the other refrigerant line is connected to the refrigerant line at the compressor inlet, and the other end is connected to the first chiller 17.

[0058] The second chiller 28 is connected to the heat pump module through two refrigerant lines. The second electronic expansion valve 26 is installed on one refrigerant line, and one end is connected to the downstream refrigerant line of the water-cooled condenser 5 and the air-cooled condenser 6, and the other end is connected to the second chiller 28. One end of the other refrigerant line is connected to the refrigerant line at the compressor inlet, and the other end is connected to the second chiller 28.

[0059] Furthermore, the heat pump module also includes a first refrigerant circuit solenoid valve 3, a second refrigerant circuit solenoid valve 4, and a third refrigerant circuit solenoid valve 9;

[0060] One end of the first refrigerant circuit solenoid valve 3 is connected to the compressor 1, and the other end is connected to the inlet of the water-cooled condenser 5;

[0061] One end of the second refrigerant circuit solenoid valve 4 is connected to the compressor 1, and the other end is connected to the inlet of the air-cooled condenser 6;

[0062] The third refrigerant circuit solenoid valve 9 is connected in series upstream of the thermal expansion valve 10 and downstream of the refrigerant inlet of the first chiller 17 and the refrigerant inlet of the second chiller 28.

[0063] The thermal management module of the motor and its drive unit also includes a first water pump 32. The first water pump 32, the air-cooled radiator 34, the second chiiller 28 and the motor and its drive unit 29 are connected in series to form a first circulating fluid loop through the circulating fluid pipeline.

[0064] The battery thermal management module also includes a second water pump 21 and a second PTC 22; the second water pump 21, the second PTC 22, the battery 24 and the first chiller 17 are connected in series through a circulating fluid pipeline to form a second external circulating fluid loop;

[0065] Furthermore, the battery thermal management module also includes a second expansion tank 20. The outlet of the second expansion tank 20 is connected to the upstream of the second water pump 21 through a pipeline, and the inlet of the second expansion tank 20 is connected to the downstream of the first chiller 17 through a pipeline. The second expansion tank 20, the second water pump 21, the second PTC 22, the battery 24 and the first chiller 17 are connected in series to form a second internal circulation liquid loop.

[0066] The second expansion tank 20 is used for water replenishment and venting of the second internal circulation liquid circuit. When the cooling demand of the battery 24 is low, the second water pump 21 can be used to draw water from the second expansion tank 20 to cool the battery 24 without activating the heat pump module, thus reducing energy consumption.

[0067] The cabin thermal management module also includes a third water pump 12, a first PTC 13, and a heater core 14; the third water pump 12, the first PTC 13, and the heater core 14 are connected in series through a circulating liquid pipeline to form a third circulating liquid loop; the evaporator 11 operates in cabin cooling mode, and the heater core 14 operates in cabin heating mode.

[0068] The first circulating fluid circuit, the second external circulating fluid circuit, and the third circulating fluid circuit can be connected to form the aforementioned total circulating fluid circuit.

[0069] The vehicle thermal management system also includes one or more first expansion tanks 36, which are connected to the first circulating fluid circuit, the second external circulating fluid circuit, the third circulating fluid circuit and the water-cooled condenser 5 through circulating fluid pipelines.

[0070] In one specific embodiment, the third water pump 12, the first PTC 13 and the warm air core 14 are connected in series with the condenser 5 to form the aforementioned third circulating liquid circuit; the first expansion tank 36 is connected to the first circulating liquid circuit, the second external circulating liquid circuit and the third circulating liquid circuit through the circulating liquid pipeline.

[0071] Several isolation valve bodies include a first three-way reversing valve 31, a second three-way reversing valve 33, a third three-way reversing valve 19, a fourth three-way reversing valve 18, a fifth three-way reversing valve 16, a first water circuit solenoid valve 35, and a second water circuit solenoid valve 15; the three reversing ports of each of the aforementioned three-way reversing valves can be interconnected.

[0072] The first reversing port I 3101 of the first three-way reversing valve 31 is connected to the third reversing port III 1903 of the third three-way reversing valve 19, the second reversing port I 3102 is connected to the first water pump 32, and the third reversing port I 3103 is connected to the motor and its drive unit 29.

[0073] The second three-way reversing valve 33 is installed on the first circulating fluid circuit. The first reversing port II 3301 of the second three-way reversing valve 33 is connected to the first water pump 32, the second reversing port II 3302 is connected to the air-cooled radiator 34, and the third reversing port II 3303 is connected to the circulating fluid pipeline between the air-cooled radiator 34 and the first chiiller 17.

[0074] The first water circuit solenoid valve 35 includes two ports, namely port I and port II. Port I is connected to the first circulating fluid circuit through a pipeline and is located between the third reversing port II 3303 of the second three-way reversing valve 33 and the second chiiller 28. The second reversing port III 1902 of the third three-way reversing valve 19 is connected to port II of the first water circuit solenoid valve 35. The first reversing port III 1901 of the third three-way reversing valve 19 is connected to the third reversing port V 1603 of the fifth three-way reversing valve 16.

[0075] The first reversing port IV1801 of the fourth three-way reversing valve 18 is connected to the interface II of the first water circuit solenoid valve 35, the second reversing port IV1802 is connected to the first chiiller 17, and the third reversing port IV1803 is connected to the third circulating liquid circuit and is located between the warm air core 14 and the water-cooled condenser 5.

[0076] The second reversing port V1602 of the fifth three-way reversing valve 16 is connected to the water-cooled condenser 5, and the first reversing port V1601 is connected to the third water pump 12; the second water circuit solenoid valve 15 is connected and installed between the second reversing port V1602 and the water-cooled condenser 5.

[0077] The vehicle thermal management system also includes a fan, an air-cooled condenser 6, an air-cooled radiator 34, and the fan arranged side by side. The fan is configured such that when it rotates in a preset direction, the air blown out flows sequentially through the air-cooled radiator 34 and the air-cooled condenser 6, or the air flows sequentially through the air-cooled radiator 34 and the air-cooled condenser 6 before being blown out by the fan. The air-cooled radiator 34 and the air-cooled condenser 6 share a single fan, which not only saves costs but also makes the overall thermal management system of the electric vehicle smaller.

[0078] The vehicle thermal management system also includes a first temperature sensor 30, a second temperature sensor 23, a third temperature sensor 25, a first temperature and pressure sensor 2, a second temperature and pressure sensor 8, and a third temperature and pressure sensor 27;

[0079] The first temperature sensor 30 is installed on the pipeline between the motor and its drive unit 29 and the third reversing port I 3103 of the first three-way reversing valve 31; the second temperature sensor 23 is installed on the pipeline between the second PTC 22 and the battery 24; the third temperature sensor 25 is installed on the pipeline between the battery 24 and the first chiller 17; the first temperature and pressure sensor 2 is installed on the pipeline at the outlet of the compressor 1; the second temperature and pressure sensor 8 is installed on the pipeline between the first chiller 17 and the heat pump module, and is located downstream of the first chiller 17; the third temperature and pressure sensor 27 is installed on the pipeline between the second chiller 28 and the heat pump module, and is located downstream of the second chiller 28.

[0080] Example 2:

[0081] Based on Example 1, this embodiment provides a method for thermal management of an electric vehicle, including control of the vehicle thermal management system under the following fifteen operating conditions:

[0082] First operating condition: See appendix Figure 2 When the cabin requires separate cooling, the first three-way reversing valve 31, the second three-way reversing valve 33, the third three-way reversing valve 19, the fourth three-way reversing valve 18, and the fifth three-way reversing valve 16 are all closed; the first refrigerant circuit solenoid valve 3 is closed, and the second refrigerant circuit solenoid valve 4 and the third refrigerant circuit solenoid valve 9 are open; the first water circuit solenoid valve 35 and the second water circuit solenoid valve 15 are all closed; the first electronic expansion valve 7 and the second electronic expansion valve 26 are all inactive, and the compressor starts.

[0083] Working principle: The circulating liquid does not flow. After the refrigerant flows out of the compressor 1, it flows in sequence through the first temperature and pressure sensor 2, the second refrigerant circuit solenoid valve 4, the air-cooled condenser 6, the third refrigerant circuit solenoid valve 9, the thermal expansion valve 10 and the evaporator 11, and then flows back into the compressor 1 to form a refrigerant circuit, so that the evaporator 11 cools the cabin.

[0084] Second operating condition: See appendix Figure 3 When the waste heat from the motor and its drive unit is directly supplied to the cabin for heating, the first reversing port 3101 and the third reversing port 3103 of the first three-way reversing valve 31 are opened, the second three-way reversing valve 33 is closed, the first reversing port 1901 and the third reversing port 1903 of the third three-way reversing valve 19 are opened, the first reversing port 1801 and the third reversing port 1803 of the fourth three-way reversing valve 18 are opened, the first reversing port 1601 and the third reversing port 1603 of the fifth three-way reversing valve 16 are opened, at least one of the second reversing port 1602 and the second water circuit solenoid valve 15 is closed, the first refrigerant circuit solenoid valve 3, the second refrigerant circuit solenoid valve 4, and the third refrigerant circuit solenoid valve 9 are all closed; the first water circuit solenoid valve 35 is opened, the first electronic expansion valve 7 and the second electronic expansion valve 26 are all inactive, and the third water pump 12 is started.

[0085] Working principle: The third water pump 12, the first PTC 13, the heater core 14, the third commutator IV 1803, the first commutator IV 1801, the second chiller 28, the motor and its drive unit 29, the first temperature sensor 30, the third commutator I 3103, the first commutator I 3101, the third commutator III 1903, the first commutator III 1901, the third commutator V 1603, and the first commutator V 1601 form a circulating fluid loop, which can use the waste heat of the motor and its drive unit to directly supply cabin heating.

[0086] Third operating condition: See appendix Figure 4When the waste heat of the motor and its drive unit 29 is supplied to the cabin for heating through the heat pump, the second reversing port 3102 and the third reversing port 3103 of the first three-way reversing valve 31 are opened, the first reversing port 3301 and the third reversing port 3303 of the second three-way reversing valve 33 are opened, the first reversing port 1901 and the second reversing port 1902 of the third three-way reversing valve 19 are opened, the first reversing port 1801 and the second reversing port 1802 of the fourth three-way reversing valve 18 are opened, the first reversing port 1601 and the second reversing port 1602 of the fifth three-way reversing valve 16 are opened, the first refrigerant circuit solenoid valve 3 is opened, the second refrigerant circuit solenoid valve 4 and the third refrigerant circuit solenoid valve 9 are both closed, the first water circuit solenoid valve 35 is closed, the second water circuit solenoid valve 15 is opened, the first electronic expansion valve 7 is not working, the second electronic expansion valve 26 is working, the compressor 1 is working, the third water pump 12 is working, and the first water pump 32 is not working.

[0087] Working principle: The first water pump 32, the first reversing port 3301 of the second three-way reversing valve 33, the third reversing port 3303 of the second three-way reversing valve 33, the second chiiller 28, the motor and its drive unit 29, the first temperature sensor 30, the third reversing port 3103 of the first three-way reversing valve 31, the second reversing port 3102 of the first three-way reversing valve 31, and the first water pump 32 form a circulating liquid circuit A;

[0088] Compressor 1, second temperature and pressure sensor 2, first refrigerant circuit solenoid valve 3, water-cooled condenser 5, second electronic expansion valve 26, second chiller 28, third temperature and pressure sensor 27, and compressor 1 form refrigerant circuit III; refrigerant circuit III and circulating liquid circuit A exchange heat through second chiller 28;

[0089] The third water pump 12, the first PTC 13, the heater core 14, the water-cooled condenser 5, the second water circuit solenoid valve 15, the second reversing port 1602 and the first reversing port 1601 of the fifth three-way reversing valve 16, and the third water pump 12 form a circulating liquid circuit B; the circulating liquid circuit B and the refrigerant circuit exchange heat through the water-cooled condenser 5.

[0090] Fourth operating condition: See appendix Figure 5When the cabin requires PTC heating, the third reversing port 1803 of the fourth three-way reversing valve 18 is closed; the first reversing port 1601 and the second reversing port 1602 of the fifth three-way reversing valve 16 are open, and the third reversing port 1603 is closed; the first three-way reversing valve 31, the second three-way reversing valve 33, and the third three-way reversing valve 19 are all closed; the first refrigerant circuit solenoid valve 3, the second refrigerant circuit solenoid valve 4, and the third refrigerant circuit solenoid valve 9 are all closed; the first water circuit solenoid valve 35 is closed; the second water circuit solenoid valve 15 is open; the first electronic expansion valve 7 and the second electronic expansion valve 26 are both inactive; the third water pump 12 is on; the first PTC 13 is on; and the compressor 1 is off.

[0091] Working principle: The third water pump 12, the first PTC 13, the heater core 14, the water-cooled condenser 5, the second water circuit solenoid valve 15, the second reversing port V1602, and the first reversing port V1601 form a circulating liquid circuit. When the first PTC 13 is started, the cabin can be heated.

[0092] Fifth operating condition: See appendix Figure 6 When the motor and its drive unit require air cooling, the second reversing port 3102 and the third reversing port 3103 of the first three-way reversing valve 31 are opened, the first reversing port 3301 and the second reversing port 3302 of the second three-way reversing valve 33 are opened, the third three-way reversing valve 19, the fourth three-way reversing valve 18 and the fifth three-way reversing valve 16 are closed, the first refrigerant circuit solenoid valve 3, the second refrigerant circuit solenoid valve 4 and the third refrigerant circuit solenoid valve 9 are all closed, the first water circuit solenoid valve 35 and the second water circuit solenoid valve 15 are closed, and the first electronic expansion valve 7 and the second electronic expansion valve 26 are all inactive.

[0093] Working principle: The first water pump 32, the first reversing port 3301 and the second reversing port 3302 of the second three-way reversing valve 33, the air-cooled radiator 34, the second chiller 28, the motor and its drive unit 29, the first temperature sensor 30, the third reversing port 3103 of the first three-way reversing valve 31, the second reversing port 3102 of the first three-way reversing valve 31, and the first water pump 32 form a circulating liquid circuit; the air-cooled radiator 34 is used for heat dissipation.

[0094] Sixth operating condition: See appendix Figure 7When battery 24 requires air cooling, the first reversing port 3101 and the second reversing port 3102 of the first three-way reversing valve 31 open; the first reversing port 3301 and the second reversing port 3302 of the second three-way reversing valve 33 open; the first reversing port 1901 and the third reversing port 1903 of the third three-way reversing valve 19 open; the first reversing port 1801 and the second reversing port 1802 of the fourth three-way reversing valve 18 open; the fifth three-way reversing valve 16 closes; the first refrigerant circuit solenoid valve 3, the second refrigerant circuit solenoid valve 4, and the third refrigerant circuit solenoid valve 9 all close; the first water circuit solenoid valve 35 opens; the second water circuit solenoid valve 15 closes; and the first electronic expansion valve 7 and the second electronic expansion valve 26 are both inactive. The second water pump 21 starts, and the first water pump 32 stops.

[0095] Working principle: The second water pump 21, the second PTC 22, the second temperature sensor 23, the battery 24, the third temperature sensor 25, the first chiller 17, the second reversing port 1802 of the fourth three-way reversing valve 18, the first reversing port 1801 of the fourth three-way reversing valve 18, the first water circuit solenoid valve 35, the air-cooled radiator 34, the second reversing port 3302 of the second three-way reversing valve 33, the first reversing port 3301 of the second three-way reversing valve 33, the first water pump 32, the second reversing port 3102 of the first three-way reversing valve 31, the first reversing port 3101 of the first three-way reversing valve 31, the third reversing port 1903 of the third three-way reversing valve 19, and the first reversing port 1901 of the third three-way reversing valve 19, together with the second water pump 21, form a circulating liquid circuit, and the battery 24 is air-cooled by the air-cooled radiator 34.

[0096] Seventh operating condition: See appendix Figure 8 When the motor, its drive unit 29, and the battery 24 all require air cooling, the first reversing port 3101, the second reversing port 3102, and the third reversing port 3103 of the first three-way reversing valve 31 open; the first reversing port 3301 and the second reversing port 3302 of the second three-way reversing valve 33 open; the first reversing port 1901 and the third reversing port 1903 of the third three-way reversing valve 19 open; the first reversing port 1801 and the second reversing port 1802 of the fourth three-way reversing valve 18 open; the second reversing port 1602 of the fifth three-way reversing valve 16 closes; at least one of the second water circuit solenoid valve 15 closes; the first refrigerant circuit solenoid valve 3, the second refrigerant circuit solenoid valve 4, and the third refrigerant circuit solenoid valve 9 all close; the first water circuit solenoid valve 35 opens; and the first electronic expansion valve 7 and the second electronic expansion valve 26 both cease operation. The second water pump 21 ceases operation, and the first water pump 32 operates.

[0097] Working principle: After the first water pump 32, the first reversing port 3301 of the second three-way reversing valve 33, the second reversing port 3302 of the second three-way reversing valve 33, and the air-cooled radiator 34, the circuit splits into two branches. Branch 1: Second chiller 28, motor and its drive unit 29, first temperature sensor 30, third reversing port 3103 of the first three-way reversing valve 31, second reversing port 3102 of the first three-way reversing valve 31, and first water pump 32. Branch 2: First water circuit solenoid valve 35, first reversing port 1801 of the fourth three-way reversing valve 18, and fourth three-way... The second reversing port 1802 of the reversing valve 18, the first chiller 17, the third temperature sensor 25, the second temperature and pressure sensor 2, the second temperature sensor 23, the second PTC 22, the second water pump 21, the first reversing port 1901 of the third three-way reversing valve 19, the third reversing port 1903 of the third three-way reversing valve 19, the first reversing port 3101 of the first three-way reversing valve 31, the second reversing port 3102 of the first three-way reversing valve 31, and the first water pump 32; the battery 24 and the motor and its drive unit 29 are all cooled by heat exchange through the air-cooled radiator 34.

[0098] Eighth operating condition: See appendix Figure 9 When the battery needs to be cooled separately, the first three-way reversing valve 31 and the second three-way reversing valve 33 are both closed, the first reversing port 1901 and the second reversing port 1902 of the third three-way reversing valve 19 are open, the first reversing port 1801 and the second reversing port 1802 of the fourth three-way reversing valve 18 are open, at least one of the second reversing port 1602 of the fifth three-way reversing valve 16 and the second water circuit solenoid valve 15 is closed, the first refrigerant circuit solenoid valve 3 and the third refrigerant circuit solenoid valve 9 are both closed, the second refrigerant circuit solenoid valve 4 is open, the first water circuit solenoid valve 35 is closed, the first electronic expansion valve 7 is working, the second electronic expansion valve 26 is not working, the second water pump 21 is working, and the compressor 1 is working.

[0099] Working principle: The second water pump 21, the second PTC 22, the second temperature sensor 23, the battery 24, the third temperature sensor 25, the first chiller 17, the second reversing port 1802 of the fourth three-way reversing valve 18, the first reversing port 1801 of the fourth three-way reversing valve 18, the second reversing port 1902 of the third three-way reversing valve 19, the first reversing port 1901 of the third three-way reversing valve 19, and the second water pump 21 form a circulating liquid circuit C;

[0100] Compressor 1, second temperature and pressure sensor 2, second refrigerant circuit solenoid valve 4, air-cooled condenser 6, first electronic expansion valve 7, first chiller 17, second temperature and pressure sensor 8, and compressor 1 form a refrigerant circuit; the refrigerant circuit and circulating liquid circuit C exchange heat through the first chiller 17 to achieve independent cooling of battery 24.

[0101] Ninth operating condition: See appendix Figure 10 When the waste heat from the motor and its drive unit is directly supplied to the battery for heating, the first reversing port 3101 and the third reversing port 3103 of the first three-way reversing valve 31 are opened, the second three-way reversing valve 33 is closed, the first reversing port 1901 and the third reversing port 1903 of the third three-way reversing valve 19 are opened, the first reversing port 1801 and the second reversing port 1802 of the fourth three-way reversing valve 18 are opened, the second reversing port 1602 of the fifth three-way reversing valve 16 and at least one of the second water circuit solenoid valve 15 are closed, the first refrigerant circuit solenoid valve 3, the second refrigerant circuit solenoid valve 4 and the third refrigerant circuit solenoid valve 9 are all closed, the first water circuit solenoid valve 35 is opened, the first electronic expansion valve 7 and the second electronic expansion valve 26 are all inactive, and the second water pump 21 is turned on.

[0102] Working principle: The second water pump 21, the second PTC 22, the second temperature sensor 23, the battery 24, the third temperature sensor 25, the first chiller 17, the second reversing port 1802 of the fourth three-way reversing valve 18, the first reversing port 1801 of the fourth three-way reversing valve 18, the first water circuit solenoid valve 35, the second chiller 28, the motor and its drive unit 29, the first temperature sensor 30, the third reversing port 3103 of the first three-way reversing valve 31, the first reversing port 3101 of the first three-way reversing valve 31, the third reversing port 1903 of the third three-way reversing valve 19, and the first reversing port 1901 of the third three-way reversing valve 19, together with the second water pump 21, form a circulating liquid circuit D. The motor and its drive unit 29 and the battery 24 are directly connected through the circulating liquid circuit D, and the waste heat of the motor and its drive unit 29 can be directly used to heat the battery 24.

[0103] The tenth operating condition: When the waste heat from the motor and its drive unit is used to heat the battery via the heat pump, the second reversing port 3102 and the third reversing port 3103 of the first three-way reversing valve 31 open; the first reversing port 3301 and the third reversing port 3303 of the second three-way reversing valve 33 open; the third three-way reversing valve 19 closes; the second reversing port 1802 and the third reversing port 1803 of the fourth three-way reversing valve 18 open; the second reversing port 1602 and the third reversing port 1603 of the fifth three-way reversing valve 16 open; the first refrigerant circuit solenoid valve 3 opens; the second refrigerant circuit solenoid valve 4 and the third refrigerant circuit solenoid valve 9 are both closed; the first water circuit solenoid valve 35 closes; the second water circuit solenoid valve 15 opens; the second electronic expansion valve 26 operates; and the first electronic expansion valve 7 does not operate. The compressor 1, the first water pump 32, and the second water pump 21 operate.

[0104] Working principle:

[0105] The first water pump 32, the first reversing port 3301 of the second three-way reversing valve 33, the third reversing port 3303 of the second three-way reversing valve 33, the second chiiller 28, the motor and its drive unit 29, the first temperature sensor 30, the third reversing port 3103 of the first three-way reversing valve 31, the second reversing port 3102 of the first three-way reversing valve 31, and the first water pump 32 form a circulating liquid circuit A;

[0106] Compressor 1, second temperature and pressure sensor 2, first refrigerant circuit solenoid valve 3, water-cooled condenser 5, second electronic expansion valve 26, second chiller 28, third temperature and pressure sensor 27, and compressor 1 form a refrigerant circuit; the refrigerant circuit and circulating liquid circuit A exchange heat through the second chiller 28;

[0107] The second water pump 21, the second PTC 22, the second temperature sensor 23, the battery 24, the third temperature sensor 25, the first chiller 17, the second reversing port 1802 of the fourth three-way reversing valve 18, the third reversing port 1803 of the fourth three-way reversing valve 18, the water-cooled condenser 5, the second water circuit solenoid valve 15, the second reversing port 1602 of the fifth three-way reversing valve 16, the third reversing port 1603 of the fifth three-way reversing valve 16, and the second water pump 21 form a circulating liquid circuit E, and the circulating liquid circuit E exchanges heat with the refrigerant circuit through the water-cooled condenser 5.

[0108] Eleventh operating condition: See Figure 12 When the battery requires water-heated PTC heating, the first three-way reversing valve 31 and the second three-way reversing valve 33 are both closed, the first reversing port 1901 and the second reversing port 1902 of the third three-way reversing valve 19 are open, the first reversing port 1801 and the second reversing port 1802 of the fourth three-way reversing valve 18 are open, the third reversing port 1603 of the fifth three-way reversing valve 16 is closed, the first refrigerant circuit solenoid valve 3, the second refrigerant circuit solenoid valve 4 and the third refrigerant circuit solenoid valve 9 are all closed, the first water circuit solenoid valve 35 is closed, the second water circuit solenoid valve 15 is closed, the first electronic expansion valve 7 and the second electronic expansion valve 26 are both inactive, the second PTC 22 is turned on, and the second water pump 21 is turned on.

[0109] The second water pump 21, the second PTC 22, the second temperature sensor 23, the battery 24, the third temperature sensor 25, the first chiller 17, the second reversing port 1802 of the fourth three-way reversing valve 18, the first reversing port 1801 of the fourth three-way reversing valve 18, the second reversing port 1902 of the third three-way reversing valve 19, and the first reversing port 1901 of the third three-way reversing valve 19, together with the second water pump 21, form a circulating liquid circuit C, and the second PTC 22 is turned on to heat the battery 24.

[0110] The twelfth operating condition: See Figure 13When both the cabin and the battery require cooling, the first three-way reversing valve 31, the second three-way reversing valve 33, and the fifth three-way reversing valve 16 are all closed, the first reversing port 1901 and the second reversing port 1902 of the third three-way reversing valve 19 are open, the first reversing port 1801 and the second reversing port 1802 of the fourth three-way reversing valve 18 are open, the first refrigerant circuit solenoid valve 3 is closed, the second refrigerant circuit solenoid valve 4 and the third refrigerant circuit solenoid valve 9 are all open, the first water circuit solenoid valve 35 and the second water circuit solenoid valve 15 are all closed, the first electronic expansion valve 7 is working, the second electronic expansion valve 26 is not working, and the second water pump 21 is working.

[0111] Working principle: Compressor 1, first temperature and pressure sensor 2, second refrigerant circuit solenoid valve 4, air-cooled condenser 6, first electronic expansion valve 7, first chiller 17, second temperature and pressure sensor 8, compressor 1 form refrigerant circuit I;

[0112] The second water pump 21, the second PTC 22, the second temperature sensor 23, the battery 24, the third temperature sensor 25, the first chiller 17, the second reversing port 1802 of the fourth three-way reversing valve 18, the first reversing port 1801 of the fourth three-way reversing valve 18, the second reversing port 1902 of the third three-way reversing valve 19, and the first reversing port 1901 of the third three-way reversing valve 19, together with the second water pump 21, form a circulating liquid circuit C; the circulating liquid circuit C and the refrigerant circuit I exchange heat through the first chiller 17 to achieve battery cooling;

[0113] Compressor 1, first temperature and pressure sensor 2, second refrigerant circuit solenoid valve 4, air-cooled condenser 6, third refrigerant circuit solenoid valve 9, thermal expansion valve 10, evaporator 11, and compressor 1 form refrigerant circuit II; evaporator 11 works to cool the cabin.

[0114] Thirteenth operating condition: See Figure 14 When the waste heat from the motor and its drive unit is directly supplied to the battery and the cabin for heating, the first reversing port 3101 and the third reversing port 3103 of the first three-way reversing valve 31 are open, the first reversing port 3301 and the third reversing port 3303 of the second three-way reversing valve 33 are open, the first reversing port 1901 and the third reversing port 1903 of the third three-way reversing valve 19 are open, the first reversing port 1801, the second reversing port 1802 and the third reversing port 1803 of the fourth three-way reversing valve 18 are open, the first reversing port 1601 and the third reversing port 1603 of the fifth three-way reversing valve 16 are open, the first refrigerant circuit solenoid valve 3, the second refrigerant circuit solenoid valve 4 and the third refrigerant circuit solenoid valve 9 are all closed, the first water circuit solenoid valve 35 is open, at least one of the second reversing port 1602 and the second water circuit solenoid valve 15 is closed, and the first electronic expansion valve 7 and the second electronic expansion valve 26 are all inactive. The third water pump 12, the second water pump 21 and the first water pump 32 are in operation.

[0115] Working principle: The first water pump 32, the first reversing port 3301 of the second three-way reversing valve 33, the third reversing port 3303 of the second three-way reversing valve 33, the second chiiller 28, the motor and its drive unit 29, the first temperature sensor 30, the third reversing port 3103 of the first three-way reversing valve 31, the second reversing port 3102 of the first three-way reversing valve 31, and the first water pump 32 form a circulating liquid circuit A;

[0116] The circulating fluid in the circulating fluid circuit A can return to the circulating fluid circuit A through the first reversing port 3101 of the first three-way reversing valve 31, the third reversing port 1903 of the third three-way reversing valve 19, the first reversing port 1901 of the third three-way reversing valve 19, the second water pump 21, the second PTC 22, the second temperature sensor 23, the battery 24, the third temperature sensor 25, the first chiller 17, the second reversing port 1802 of the fourth three-way reversing valve 18, the first reversing port 1801 of the fourth three-way reversing valve 18, and the first water circuit solenoid valve 35, so as to realize the use of the waste heat of the motor and its drive unit 29 to directly heat the battery 24;

[0117] The circulating fluid in the circulating fluid circuit A can also return to the circulating fluid circuit A through the first reversing port 3101 of the first three-way reversing valve 31, the third reversing port 1903 of the third three-way reversing valve 19, the first reversing port 1901 of the third three-way reversing valve 19, the third reversing port 1603 of the fifth three-way reversing valve 16, the first reversing port 1601 of the fifth three-way reversing valve 16, the third water pump 12, the first PTC 13, the heater core 14, the third reversing port 1803 of the fourth three-way reversing valve 18, the first reversing port 1801 of the fourth three-way reversing valve 18, and the first water circuit solenoid valve 35; thus realizing the direct supply of cabin heating using the waste heat of the motor and its drive unit 29.

[0118] Fourteenth operating condition: See Figure 15 When the waste heat from the motor and its drive unit simultaneously heats the battery and the cabin via the heat pump, the second reversing port 3102 and the third reversing port 3103 of the first three-way reversing valve 31 open, and at least one of the first reversing port 3101 of the first three-way reversing valve 31 and the third reversing port 1903 of the third three-way reversing valve 19 closes; the first reversing port 3301 and the third reversing port 3303 of the second three-way reversing valve 33 open, the third reversing port 1803 of the fourth three-way reversing valve 18 opens, the first reversing port 1601, the second reversing port 1602 and the third reversing port 1603 of the fifth three-way reversing valve 16 are all open, the first refrigerant circuit solenoid valve 3 opens, the second refrigerant circuit solenoid valve 4 and the third refrigerant circuit solenoid valve 9 are all closed, the first water circuit solenoid valve 35 closes, the second water circuit solenoid valve 15 opens, the first electronic expansion valve 7 does not work, and the second electronic expansion valve 26 works. The third water pump 12, the second water pump 21 and the first water pump 32 are all turned on;

[0119] Working principle: The first water pump 32, the first reversing port 3301 of the second three-way reversing valve 33, the third reversing port 3303 of the second three-way reversing valve 33, the second chiiller 28, the motor and its drive unit 29, the first temperature sensor 30, the third reversing port 3103 of the first three-way reversing valve 31, the second reversing port 3102 of the first three-way reversing valve 31, and the first water pump 32 form a circulating liquid circuit A;

[0120] The second water pump 21, the second PTC 22, the second temperature sensor 23, the battery 24, the third temperature sensor 25, the first chiller 17, the second reversing port 1802 of the fourth three-way reversing valve 18, the third reversing port 1803 of the fourth three-way reversing valve 18, the water-cooled condenser 5, the second water circuit solenoid valve 15, the second reversing port 1602 of the fifth three-way reversing valve 16, the third reversing port 1603 of the fifth three-way reversing valve 16, and the second water pump 21 form a circulating liquid circuit E, and the circulating liquid circuit E exchanges heat with the refrigerant circuit through the water-cooled condenser 5.

[0121] The third water pump 12, the first PTC 13, the heater core 14, the water-cooled condenser 5, the second water circuit solenoid valve 15, the second reversing port 1602 and the first reversing port 1601 of the fifth three-way reversing valve 16, and the third water pump 12 form a circulating liquid circuit B; the circulating liquid circuit B and the refrigerant circuit exchange heat through the water-cooled condenser 5.

[0122] The fifteenth operating condition: See [link / reference] Figure 16 When the motor and its drive unit, along with waste heat from the battery, simultaneously supply heat to the cabin via the heat pump, the second reversing port 3102 and the third reversing port 3103 of the first three-way reversing valve 31 open; the first reversing port 3301 and the third reversing port 3303 of the second three-way reversing valve 33 open; the first reversing port 1901 and the second reversing port 1902 of the third three-way reversing valve 19 open; at least one of the third reversing port 1903 of the third three-way reversing valve 19 and the first reversing port 3101 of the first three-way reversing valve 31 closes; and the fourth three-way reversing valve 1... The first reversing port 1801 and the second reversing port 1802 of valve 8 are open; the first reversing port 1601 and the second reversing port 1602 of the fifth three-way reversing valve 16 are open; the third reversing port 1603 is closed; the first refrigerant circuit solenoid valve 3 is open; the second refrigerant circuit solenoid valve 4 and the third refrigerant circuit solenoid valve 9 are both closed; the first water circuit solenoid valve 35 is closed; the second water circuit solenoid valve 15 is open; the first electronic expansion valve 7 and the second electronic expansion valve 26 are both working; the compressor 1, the third water pump 12, the second water pump 21, and the first water pump 32 are all working.

[0123] Working principle: The first water pump 32, the first reversing port 3301 of the second three-way reversing valve 33, the third reversing port 3303 of the second three-way reversing valve 33, the second chiiller 28, the motor and its drive unit 29, the first temperature sensor 30, the third reversing port 3103 of the first three-way reversing valve 31, the second reversing port 3102 of the first three-way reversing valve 31, and the first water pump 32 form a circulating liquid circuit A;

[0124] Compressor 1, first temperature and pressure sensor 2, first refrigerant circuit solenoid valve 3, water-cooled condenser 5, second chiller 28, third temperature and pressure sensor 27, and compressor 1 form refrigerant circuit III; refrigerant circuit III and circulating liquid circuit A exchange heat through second chiller 28;

[0125] The second water pump 21, the second PTC 22, the second temperature sensor 23, the battery 24, the third temperature sensor 25, the first chiller 17, the second reversing port 1802 of the fourth three-way reversing valve 18, the first reversing port 1801 of the fourth three-way reversing valve 18, the second reversing port 1902 of the third three-way reversing valve 19, and the first reversing port 1901 of the third three-way reversing valve 19, together with the second water pump 21, form a circulating liquid circuit C;

[0126] Compressor 1, first temperature and pressure sensor 2, first refrigerant circuit solenoid valve 3, water-cooled condenser 5, first electronic expansion valve 7, first chiller 17, second temperature and pressure sensor 8, and compressor 1 form refrigerant circuit IV; refrigerant circuit IV and circulating liquid circuit C exchange heat through first chiller 17;

[0127] The third water pump 12, the first PTC 13, the heater core 14, the water-cooled condenser 5, the second water circuit solenoid valve 15, the second reversing port 1602 and the first reversing port 1601 of the fifth three-way reversing valve 16, and the third water pump 12 form a circulating liquid circuit B; the circulating liquid circuit B and the refrigerant circuit exchange heat through the water-cooled condenser 5. This enables the use of the motor and its drive unit, as well as waste heat from the battery, to heat the cabin via a heat pump.

[0128] In summary, the above are merely preferred embodiments of the present invention and are not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A thermal management system for an electric vehicle, characterized in that, include: Heat pump module, motor and its drive unit thermal management module, battery thermal management module and cabin thermal management module; The heat pump module is equipped with a water-cooled condenser and an evaporator. The evaporator is installed in the cabin and is used for cabin cooling. A total circulating liquid loop is formed between the motor and its drive unit thermal management module, the battery thermal management module, the cabin thermal management module, and the water-cooled condenser; the total circulating liquid loop is equipped with several isolation valves for disconnecting and connecting at least two of the motor and its drive unit thermal management module, the battery thermal management module, the cabin thermal management module, and the water-cooled condenser; The motor and its drive unit thermal management module is used to heat or cool the motor and its drive unit. The motor and its drive unit thermal management module is equipped with a second chiiller, and the water-cooled condenser can exchange heat with the second chiiller. The battery thermal management module is used to heat or cool the battery. The battery thermal management module is equipped with a first chiiller, and the water-cooled condenser can exchange heat with the first chiiller. Several isolation valve bodies include a first three-way reversing valve, a second three-way reversing valve, a third three-way reversing valve, a fourth three-way reversing valve, a fifth three-way reversing valve, a first water circuit solenoid valve, and a second water circuit solenoid valve; the three reversing ports of each three-way reversing valve can be interconnected; The first reversing port I of the first three-way reversing valve is connected to the third reversing port III of the third three-way reversing valve, the second reversing port I is connected to the first water pump, and the third reversing port I is connected to the motor and its drive unit. The second three-way reversing valve is installed on the first circulating fluid circuit. The first reversing port II of the second three-way reversing valve is connected to the first water pump, the second reversing port II is connected to the air-cooled radiator, and the third reversing port II is connected to the circulating fluid pipeline between the air-cooled radiator and the first chiller. The first water circuit solenoid valve includes two ports, namely port I and port II. Port I is connected to the first circulating fluid circuit through a pipeline and is located between the third reversing port II of the second three-way reversing valve and the second chiiller. The second reversing port III of the third three-way reversing valve is connected to port II of the first water circuit solenoid valve. The first reversing port III of the third three-way reversing valve is connected to the third reversing port V of the fifth three-way reversing valve. The first reversing port IV of the fourth three-way reversing valve is connected to the interface II of the first water circuit solenoid valve, the second reversing port IV is connected to the first chiiller, and the third reversing port IV is connected to the third circulating liquid circuit and is located between the warm air core and the water-cooled condenser. The second reversing port V of the fifth three-way reversing valve is connected to the water-cooled condenser, and the first reversing port V is connected to the third water pump; the second water circuit solenoid valve is connected between the second reversing port V and the water-cooled condenser.

2. The electric vehicle thermal management system as described in claim 1, characterized in that, The thermal management module of the motor and its drive unit also includes a first water pump. The first water pump, the air-cooled radiator, the second chiller, and the motor and its drive unit are connected in series to form a first circulating fluid loop. The battery thermal management module also includes a second water pump and a second PTC; the second water pump, the second PTC, the battery and the first chiller are connected in series through a circulating fluid pipeline to form a second external circulating fluid loop; The cabin thermal management module also includes a third water pump, a first PTC, and a heater core; the third water pump, the first PTC, and the heater core are connected in series with the condenser to form a third circulating fluid loop; The first circulating fluid circuit, the second external circulating fluid circuit, and the third circulating fluid circuit can be connected to form the aforementioned total circulating fluid circuit.

3. The electric vehicle thermal management system as described in claim 2, characterized in that, The heat pump module also includes a compressor, an air-cooled condenser, a thermal expansion valve, a first electronic expansion valve, and a second electronic expansion valve; The compressor, water-cooled condenser, thermostatic expansion valve, and evaporator are connected in series to form a loop via refrigerant piping; the air-cooled condenser and the water-cooled condenser are connected in parallel; the first electronic expansion valve is located on the refrigerant piping between the heat pump module and the first chiller, and is located upstream of the first chiller; the second electronic expansion valve is located on the refrigerant piping between the heat pump module and the second chiller, and is located upstream of the second chiller.

4. The electric vehicle thermal management system as described in claim 1, characterized in that, The vehicle thermal management system also includes a first temperature sensor, a second temperature sensor, a third temperature sensor, a first temperature and pressure sensor, a second temperature and pressure sensor, and a third temperature and pressure sensor; The first temperature sensor is installed on the pipeline between the motor and its drive unit and the third reversing port I of the first three-way reversing valve; the second temperature sensor is installed on the pipeline between the second PTC and the battery; the third temperature sensor is installed on the pipeline between the battery and the first chiller; the first temperature and pressure sensor is installed on the pipeline at the compressor outlet; the second temperature and pressure sensor is installed on the pipeline between the first chiller and the heat pump module, and is located downstream of the first chiller; the third temperature and pressure sensor is installed on the pipeline between the second chiller and the heat pump module, and is located downstream of the second chiller.

5. The electric vehicle thermal management system as described in any one of claims 2-4, characterized in that, The air-cooled condenser, air-cooled radiator, and fan are arranged side by side.

6. The electric vehicle thermal management system as described in any one of claims 2-4, characterized in that, The battery thermal management module also includes a second expansion tank. The outlet of the second expansion tank is connected to the upstream of the second water pump through a pipeline, and the inlet of the second expansion tank is connected to the downstream of the second chiller through a pipeline. The second expansion tank, the second water pump, the second PTC, the battery and the second chiller are connected in series to form a second internal circulation water loop.

7. A method for thermal management of an electric vehicle, based on the thermal management system for an electric vehicle as described in any one of claims 4-6, comprising controlling the thermal management system under the following operating conditions: Operating Condition 1: When the waste heat from the motor and its drive unit is directly supplied to the cabin for heating, the first and third reversing ports of the first three-way reversing valve are open, the second three-way reversing valve is closed, the first and third reversing ports of the third three-way reversing valve are open, the first and third reversing ports of the fourth three-way reversing valve are open, the first and third reversing ports of the fifth three-way reversing valve are open, at least one of the second reversing port and the second water circuit solenoid valve is closed, and the first, second, and third refrigerant circuit solenoid valves are all closed; the first water circuit solenoid valve is open, the first and second electronic expansion valves are both inactive, and the third water pump is started; Operating Condition 2: When the waste heat from the motor and its drive unit is supplied to the cabin for heating via the heat pump, the second and third reversing ports of the first three-way reversing valve are open, the first and third reversing ports of the second three-way reversing valve are open, the first and second reversing ports of the third three-way reversing valve are open, the first and second reversing ports of the fourth three-way reversing valve are open, the first and second reversing ports of the fifth three-way reversing valve are open, the first refrigerant circuit solenoid valve is open, the second and third refrigerant circuit solenoid valves are both closed, the first water circuit solenoid valve is closed, the second water circuit solenoid valve is open, the first electronic expansion valve is not working, the second electronic expansion valve is working, the compressor is working, the third water pump is working, and the first water pump is not working. Operating Condition 3: When the waste heat from the motor and its drive unit is directly supplied to the battery for heating, the first and third reversing ports of the first three-way reversing valve are open, the second three-way reversing valve is closed, the first and third reversing ports of the third three-way reversing valve are open, the first and second reversing ports of the fourth three-way reversing valve are open, the second reversing port of the fifth three-way reversing valve and at least one of the second water circuit solenoid valves are closed, the first, second, and third refrigerant circuit solenoid valves are all closed, the first water circuit solenoid valve is open, the first and second electronic expansion valves are all inactive, and the second water pump is turned on. Operating Condition 4: When the waste heat from the motor and its drive unit is used to heat the battery through the heat pump, the second and third reversing ports of the first three-way reversing valve open, the first and third reversing ports of the second three-way reversing valve open, the third three-way reversing valve closes, the second and third reversing ports of the fourth three-way reversing valve open, the second and third reversing ports of the fifth three-way reversing valve open, the first refrigerant circuit solenoid valve opens, the second and third refrigerant circuit solenoid valves are both closed, the first water circuit solenoid valve closes, the second water circuit solenoid valve opens, the second electronic expansion valve operates, the first electronic expansion valve does not operate, and the compressor, the first water pump, and the second water pump operate. Operating Condition 5: When the waste heat from the motor and its drive unit is directly supplied to the battery and cabin heating, the first and third reversing ports of the first three-way reversing valve are open, the first and third reversing ports of the second three-way reversing valve are open, the first and third reversing ports of the third three-way reversing valve are open, the first, second, and third reversing ports of the fourth three-way reversing valve are open, the first and third reversing ports of the fifth three-way reversing valve are open, the first, second, and third reversing ports of the reversing valve are all closed, the first water circuit solenoid valve is open, at least one of the second reversing port and the second water circuit solenoid valve is closed, the first and second electronic expansion valves are all inactive, and the third, second, and first water pumps are operational. Operating Condition 6: When the waste heat from the motor and its drive unit simultaneously heats the battery and the cabin through the heat pump, the second and third reversing ports of the first three-way reversing valve are open, and at least one of the first reversing port of the first three-way reversing valve and the third reversing port of the third three-way reversing valve is closed; the first and third reversing ports of the second three-way reversing valve are open, the third reversing port of the fourth three-way reversing valve is open, and all three reversing ports of the fifth three-way reversing valve are open; the first refrigerant circuit solenoid valve is open, and all two refrigerant circuit solenoid valves are closed; the first water circuit solenoid valve is closed, and the second water circuit solenoid valve is open; the first electronic expansion valve is not working, the second electronic expansion valve is working, and the third, second, and first water pumps are all turned on. Operating Condition 7: When the motor and its drive unit, and the waste heat from the battery are simultaneously supplied to the cabin for heating via the heat pump, the second and third reversing ports of the first three-way reversing valve are open, the first and third reversing ports of the second three-way reversing valve are open, the first and second reversing ports of the third three-way reversing valve are open, at least one of the third reversing port of the third three-way reversing valve and the first reversing port of the first three-way reversing valve is closed, the first and second reversing ports of the fourth three-way reversing valve are open, the first and second reversing ports of the fifth three-way reversing valve are open, the third reversing port is closed, the first refrigerant circuit solenoid valve is open, both the second and third refrigerant circuit solenoid valves are closed, the first water circuit solenoid valve is closed, the second water circuit solenoid valve is open, both the first and second electronic expansion valves are working, and the compressor, the third water pump, the second water pump, and the first water pump are all working.

8. The method for thermal management of an electric vehicle as described in claim 7, characterized in that, This also includes the control of the vehicle thermal management system under the following operating conditions: Operating Condition 8: When the motor and its drive unit require air cooling, the second and third reversing ports of the first three-way reversing valve are open, the first and second reversing ports of the second three-way reversing valve are open, the third, fourth, and fifth three-way reversing valves are closed, the first, second, and third refrigerant circuit solenoid valves are all closed, the first and second water circuit solenoid valves are closed, and the first and second electronic expansion valves are all inactive. Operating Condition 9: When the battery requires air cooling, the first and second reversing ports of the first three-way reversing valve are open, the first and second reversing ports of the second three-way reversing valve are open, the first and third reversing ports of the third three-way reversing valve are open, the first and second reversing ports of the fourth three-way reversing valve are open, the fifth three-way reversing valve is closed, the first, second, and third refrigerant circuit solenoid valves are all closed, the first water circuit solenoid valve is open, the second water circuit solenoid valve is closed, the first electronic expansion valve and the second electronic expansion valve are both inactive, the second water pump is on, and the first water pump is off. Operating Condition 10: When the motor, its drive unit, and battery all require air cooling, the first, second, and third reversing ports of the first three-way reversing valve are open; the first and second reversing ports of the second three-way reversing valve are open; the first and third reversing ports of the third three-way reversing valve are open; the first and second reversing ports of the fourth three-way reversing valve are open; the second reversing port of the fifth three-way reversing valve is closed; at least one of the second water circuit solenoid valves is closed; all three refrigerant circuit solenoid valves (first, second, and third) are closed; the first water circuit solenoid valve is open; both the first and second electronic expansion valves are not working; the second water pump is not working; and the first water pump is working.

9. A method for thermal management of an electric vehicle as described in claim 7 or 8, characterized in that, This also includes the control of the vehicle thermal management system under the following operating conditions: Operating Condition 11: When the cabin requires separate cooling, the first three-way reversing valve, the second three-way reversing valve, the third three-way reversing valve, the fourth three-way reversing valve, and the fifth three-way reversing valve are all closed; the first refrigerant circuit solenoid valve is closed, and the second and third refrigerant circuit solenoid valves are open; the first and second water circuit solenoid valves are all closed; the first and second electronic expansion valves are both inactive, and the compressor starts. Operating Condition 12: When the cabin requires PTC heating, the third reversing port of the fourth three-way reversing valve is closed, the first and second reversing ports of the fifth three-way reversing valve are open, the third reversing port is closed, the first, second, and third three-way reversing valves are all closed, the first, second, and third refrigerant circuit solenoid valves are all closed, the first water circuit solenoid valve is closed, the second water circuit solenoid valve is open, the first and second electronic expansion valves are not working, the third water pump is on, the first PTC is on, and the compressor is not on. Operating Condition 13: When the battery requires independent cooling, both the first and second three-way reversing valves are closed; the first and second reversing ports of the third three-way reversing valve are open; the first and second reversing ports of the fourth three-way reversing valve are open; the second reversing port of the fifth three-way reversing valve and at least one of the second water circuit solenoid valves are closed; both the first and third refrigerant circuit solenoid valves are closed; the second refrigerant circuit solenoid valve is open; the first water circuit solenoid valve is closed; the first electronic expansion valve is working; the second electronic expansion valve is not working; the second water pump is working; and the compressor is working. Operating Condition 14: When the battery requires water heating PTC, the first three-way reversing valve and the second three-way reversing valve are both closed, the first and second reversing ports of the third three-way reversing valve are open, the first and second reversing ports of the fourth three-way reversing valve are open, the third reversing port of the fifth three-way reversing valve is closed, the first, second, and third refrigerant circuit solenoid valves are all closed, the first and second water circuit solenoid valves are closed, the first and second water circuit solenoid valves are closed, the first and second electronic expansion valves are not working, the second PTC is turned on, and the second water pump is turned on. Operating Condition 15: When both the cabin and battery require cooling, the first three-way reversing valve, the second three-way reversing valve, and the fifth three-way reversing valve are all closed; the first and second reversing ports of the third three-way reversing valve are open; the first and second reversing ports of the fourth three-way reversing valve are open; the first refrigerant circuit solenoid valve is closed; the second and third refrigerant circuit solenoid valves are all open; the first and second water circuit solenoid valves are all closed; the first electronic expansion valve is working; the second electronic expansion valve is not working; and the second water pump is working.

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