An electric vehicle thermal management system

Abstract

The application discloses a kind of electric vehicle thermal management system in the technical field of automobile heat pump, including air conditioning module and ten-way valve, each valve port on the ten-way valve is connected with external heat exchange branch, electric drive medium branch with pump, battery medium branch, internal refrigeration branch and internal heating branch with pump.The application uses a water condenser and a plate evaporator as air conditioning module respectively to emit heat and absorb heat window, for refrigerant, without switching path flow direction, refrigerant only flows in a fixed circuit, reduces risk and maintenance cost, and further uses ten-way valve to cooperate with heat-conducting medium to carry out refrigeration, heating, dehumidification, waste heat recovery heat exchange according to demand for passenger cabin, battery, electric drive, with low circuit complexity, adapt to multiple working conditions.

Description

Technical Field

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

[0002] The heat pump system is a core component of electric vehicles. This system not only enables the power battery and drive motor to operate within a suitable temperature range, but also provides cooling, dehumidification, or heating functions for the passenger compartment. New energy vehicles lack a stable source of waste heat. The use of advanced heat pump technology can achieve various forms of heat exchange under different needs, thereby improving the overall vehicle energy efficiency and extending the driving range in winter.

[0003] Existing electric vehicle heat pump systems have the following shortcomings: the refrigerant is generally a flammable and explosive medium, and the refrigerant circuit is complex in order to adapt to various operating conditions, which increases the risk of leakage and the difficulty of maintenance; there is a lack of highly integrated adjustment methods, the circuit is complex when there are many types of operating conditions, or the circuit is simple when there are few types of operating conditions, resulting in poor heat utilization. Summary of the Invention

[0004] The purpose of this invention is to provide a thermal management system for electric vehicles, which solves the problems of existing thermal management systems being unable to simultaneously handle complexity and number of operating conditions, as well as the high risk associated with refrigerant circuits.

[0005] The present invention achieves the above objectives through the following technical solutions: An electric vehicle thermal management system includes an air conditioning module and a ten-way valve. Each valve port on the ten-way valve is connected to an external heat exchange branch, an electric drive medium branch with a pump, a battery medium branch, an internal cooling branch, and an internal heating branch with a pump. The air conditioning module includes, according to the medium flow direction, a compressor, a first flow channel of a water condenser, and a first flow channel of a plate evaporator; The second flow channel of the water condenser is connected in series in the internal heating branch. A first three-way valve is provided between one end of the battery medium branch, one end of the internal cooling branch and one end of the second flow channel of the plate evaporator. The other end is connected to different valve ports of the ten-way valve. A second pump is provided at the connection between the second flow channel of the plate evaporator and the valve port. The inlet of the second pump is connected to the valve port.

[0006] As a preferred embodiment of the present invention, the ten-way valve includes Valve port 1 and valve port 2 are connected to both ends of the external heat exchange branch; valve port 3 and valve port 4 are connected to both ends of the internal heating branch; valve port 5 is connected to one end of the battery medium branch. Valve port seven is connected to the end of the second pump; Valve port eight is connected to one end of the internal refrigeration branch. Valve port nine and valve port ten are connected at both ends of the electric drive medium branch.

[0007] As a preferred embodiment of the present invention, the battery medium branch includes a battery flow channel connected to valve port five, and the ten-way valve also includes valve port six. The inlet of the battery flow channel is connected to the first three-way valve and valve port six, and the outlet is connected to valve port five.

[0008] As a preferred embodiment of the present invention, the internal heating branch includes a third pump, a second flow channel of a water condenser, an electric auxiliary heating unit, and a heating core according to the medium flow direction. A bridging branch is also provided between the heating core and the valve port four. The bridging branch connects the battery flow channel inlet and the second pump outlet. A throttling pipe is provided between the battery flow channel inlet and the second pump outlet.

[0009] As a preferred embodiment of the present invention, a second three-way valve is provided between the heating core, valve port four and bridging branch. The inlet of the second three-way valve is connected to the heating core, one outlet is connected to the ten-way valve, and the other outlet is connected to the bridging branch.

[0010] As a preferred embodiment of the present invention, both the first three-way valve and the second three-way valve are proportional regulating three-way valves.

[0011] As a preferred embodiment of the present invention, the electric drive medium branch includes a connection between a first pump and an electric drive channel, wherein the inlet of the first pump is connected to valve port nine, and the electric drive channel is connected to valve port ten.

[0012] As a preferred embodiment of the present invention, the first flow channel inlet of the plate evaporator is provided with a first electronic expansion valve and a drying bottle.

[0013] As a preferred embodiment of the present invention, a second electronic expansion valve is connected in parallel at both ends of the compressor.

[0014] As a preferred embodiment of the present invention, the refrigerant of the air conditioning module is one of tetrafluoroethane, tetrafluoropropylene, or propane.

[0015] The beneficial effects of this invention are as follows: This invention uses a water condenser and a plate evaporator as the heat release and heat absorption windows of the air conditioning module, respectively. For the refrigerant, there is no need to switch the flow path. The refrigerant only flows in a fixed loop, which reduces the risk and maintenance cost. Furthermore, a ten-way valve is used in conjunction with a heat transfer medium to perform cooling, heating, dehumidification, and waste heat recovery heat exchange on demand for the passenger compartment, battery, and electric drive. Its circuit complexity is low and it can adapt to a variety of operating conditions. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the overall system of the present invention; Figure 2 This is a schematic diagram of the first working condition of the present invention; Figure 3This is a schematic diagram of the second operating condition of the present invention; Figure 4 This is a schematic diagram of the third operating condition of the present invention; Figure 5 This is a schematic diagram of the fourth operating condition of the present invention; Figure 6 This is a schematic diagram of the fifth operating condition of the present invention; Figure 7 This is a schematic diagram of the sixth operating condition of the present invention; Figure 8 This is a schematic diagram of the seventh operating condition of the present invention; Figure 9 This is a schematic diagram of the eighth operating condition of the present invention; Figure 10 This is a schematic diagram of the ninth operating condition of the present invention; Figure 11 This is a schematic diagram of the tenth operating condition of the present invention; Figure 12 This is a schematic diagram of a system according to a second embodiment of the present invention; In the diagram: 1. Air conditioning module; 11. Compressor; 12. Water condenser; 13. Dryer bottle; 14. First electronic expansion valve; 15. Plate evaporator; 16. Second electronic expansion valve; 2. Ten-way valve; 21. Valve port one; 22. Valve port two; 23. Valve port three; 24. Valve port four; 25. Valve port five; 26. Valve port six; 27. Valve port seven; 28. Valve port eight; 29. ​​Valve port nine; 210. Valve port ten; 3. External heat exchange branch; 31. Radiator; 4. Electric drive medium branch; 41. Electric drive flow channel; 42. First pump; 5. Battery medium branch; 51. Second pump; 52. First three-way valve; 53. Battery flow channel; 54. Throttling tube; 6. Internal refrigeration branch; 7. Internal heating branch; 71. Third pump; 72. Electric auxiliary heating unit; 73. Heating core; 74. Second three-way valve. Detailed Implementation

[0017] The present application will now be described in further detail with reference to the accompanying drawings. It should be noted that the following specific embodiments are only used to further illustrate the present application and should not be construed as limiting the scope of protection of the present application. Those skilled in the art can make some non-essential improvements and adjustments to the present application based on the above application content.

[0018] Example 1

[0019] like Figures 1-11As shown, an electric vehicle thermal management system includes an air conditioning module 1 and a ten-way valve 2. Each port of the ten-way valve 2 is connected to an external heat exchange branch 3, an electric drive medium branch 4 with a pump, a battery medium branch 5, an internal cooling branch 6, and an internal heating branch 7 with a pump. The air conditioning module 1 includes a compressor 11, a first flow channel of a water condenser 12, and a first flow channel of a plate evaporator 15, according to the flow direction of the medium. The second flow channel of the water condenser 12 is connected in series in the internal heating branch 7. A first three-way valve 52 is provided between one end of the battery medium branch 5 and the internal cooling branch 6 and one end of the second flow channel of the plate evaporator 15. The other end of each valve is connected to a different port of the ten-way valve 2. A second pump 51 is provided at the connection between the second flow channel of the plate evaporator 15 and the valve port. The inlet of the second pump 51 is connected to the valve port. The external heat exchange branch 3 includes a radiator 31.

[0020] In this embodiment, a water condenser 12 and a plate evaporator 15 serve as the heat release and heat absorption windows of the air conditioning module 1, respectively. For the refrigerant, there is no need to switch the flow path; the refrigerant flows only within a fixed loop, reducing risks and maintenance costs. Furthermore, a ten-way valve 2 is used in conjunction with a heat transfer medium to exchange heat for cooling, heating, dehumidification, and waste heat recovery in the passenger compartment, battery, and electric drive as needed. The loop has low complexity and is adaptable to a variety of operating conditions. In this embodiment, the heat transfer medium is water (with added antifreeze). The system also includes several temperature and pressure sensors to detect the temperature at various nodes in the refrigerant and heat transfer medium.

[0021] Preferably, the ten-way valve 2 includes: valve port 1 21 and valve port 22 connected to both ends of the external heat exchange branch 3; valve port 3 23 and valve port 4 24 connected to both ends of the internal heating branch 7; valve port 5 25 connected to one end of the battery medium branch 5; valve port 7 27 connected to the end of the second pump 51; valve port 8 28 connected to one end of the internal cooling branch 6; and valve port 9 29 and valve port 10 210 connected to both ends of the electric drive medium branch 4.

[0022] Preferably, the battery medium branch 5 includes a battery flow channel 53 connected to valve port 5 25, and the ten-way valve 2 also includes valve port 6 26. The inlet of the battery flow channel 53 is connected to the first three-way valve 52 and valve port 6 26, and the outlet is connected to valve port 5 25.

[0023] Preferably, the internal heating branch 7 includes, according to the medium flow direction, a third pump 71, a second flow channel of the water condenser 12, an electric auxiliary heating unit 72, and a heating core 73. A bridging branch is also provided between the heating core 73 and the valve port 24. The bridging branch connects the inlet of the battery flow channel 53 and the outlet of the second pump 51. A throttling pipe 54 is provided between the inlet of the battery flow channel 53 and the outlet of the second pump 51.

[0024] Preferably, a second three-way valve 74 is provided between the heating core 73, valve port 24 and bridging branch. The inlet of the second three-way valve 74 is connected to the heating core 73, one outlet is connected to the ten-way valve 2, and the other outlet is connected to the bridging branch.

[0025] Preferably, the first three-way valve 52 and the second three-way valve 74 are both proportional regulating three-way valves, which are used to regulate the flow ratio of the two outlets.

[0026] Preferably, the electric drive medium branch 4 includes a connection between a first pump 42 and an electric drive channel 41, with the inlet of the first pump 42 connected to valve port 29 and the electric drive channel 41 connected to valve port 210.

[0027] Preferably, the first flow channel inlet of the plate evaporator 15 is provided with a first electronic expansion valve 14 and a drying bottle 13. The drying bottle 13 is used to store temporarily excess refrigerant and remove moisture from the refrigerant.

[0028] Preferably, the refrigerant of the air conditioning module 1 is one of tetrafluoroethane, tetrafluoropropylene, or propane.

[0029] The specific implementation method is as follows: After the air conditioning module 2 is started, its refrigerant circuit remains unchanged, releasing heat in the water condenser 12 and absorbing heat in the plate evaporator 15.

[0030] First operating condition: Please refer to... Figure 2 This operating condition is used for dual cooling of the battery and the passenger compartment, or for dehumidification of the passenger compartment. In this condition, valve port 22 and valve port 33 of the ten-way valve 2 are connected, valve port 424 and valve port 929 are connected, valve port 121 and valve port 10210 are connected, and valve port 525, valve port 727 and valve port 828 are connected together. Both outlets of the first three-way valve 52 are open, and the second three-way valve 74 is open toward the outlet of valve port 424. In this condition, the heat from the water condenser 12 passes through the internal heating branch 7 and the electric drive medium branch 4, and is finally dissipated to the external environment through the external heat exchange branch 3. The internal heating branch 7 only acts as a flow channel and does not open to deliver hot air to the passenger compartment. The plate evaporator 15 distributes the low-temperature heat transfer medium to the internal cooling branch 6 and the battery flow channel 53 through the first three-way valve 52. The distribution ratio is determined based on the cooling demand.

[0031] Second operating condition: Please refer to Figure 3This operating condition is used for refrigeration or dehumidification of the crew cabin. In this condition, valve port 22 and valve port 23 of the ten-way valve 2 are connected, valve port 24 and valve port 29 are connected, valve port 1 and valve port 210 are connected, and valve port 7 and valve port 8 are connected. The first three-way valve 52 is opened toward the outlet of the internal refrigeration branch 6, and the second three-way valve 74 is opened toward the outlet of valve port 24. In this operating condition, the heat from the water condenser 12 passes through the internal heating branch 7 and the electric drive medium branch 4, and is finally dissipated to the external environment through the external heat exchange branch 3. The plate evaporator 15 delivers the low-temperature heat transfer medium to the internal refrigeration branch 6 through the first three-way valve 52.

[0032] Third operating condition: Please refer to Figure 4 In this operating condition, the battery is cooled. In this condition, the valve ports 22 and 23 of the ten-way valve 2 are connected, the valve ports 24 and 29 are connected, the valve ports 1 and 210 are connected, and the valve ports 25 and 27 are connected. The first three-way valve 52 is open towards the outlet of the battery flow channel 53, and the second three-way valve 74 is open towards the outlet of the fourth valve 24. In this condition, the heat from the water condenser 12 passes through the internal heating branch 7 and the electric drive medium branch 4, and is finally dissipated to the external environment through the external heat exchange branch 3. The plate evaporator 15 delivers the low-temperature heat transfer medium to the battery flow channel 53 through the first three-way valve 52. The second pump 51 delivers a small amount of heat transfer medium to the battery flow channel 53 through the throttling pipe 54, allowing some slightly warmer water to flow out from the second pump 51 and mix with the cold water flowing out from the first three-way valve 52, thus appropriately increasing the water temperature entering the battery flow channel 53.

[0033] Fourth operating condition: Please refer to Figure 5 This operating condition is used for battery and electric drive heat dissipation. In this condition, valve port 22 and valve port 23 of the ten-way valve 2 are connected, valve port 25 and valve port 29 are connected, valve port 21 and valve port 210 are connected, and the second three-way valve 74 is opened toward the outlet of the battery flow channel 53. In this operating condition, the air conditioning module 1 is closed, and the heating core 73 only acts as a flow channel. The heat of the battery flow channel 53 and the electric drive 41 flow channel is dissipated through the radiator 31.

[0034] Fifth operating condition: Please refer to Figure 6 This operating condition is used for battery equalization and passenger compartment heating. In this condition, valve port 1 21, valve port 5 25 and valve port 7 27 of the ten-way valve 2 are connected, valve port 22 and valve port 6 26 are connected, and valve port 3 23 and valve port 4 24 are connected. The first three-way valve 52 is opened toward the outlet of the battery flow channel 53, and the second three-way valve 74 is opened toward the outlet of valve port 4 24. In this operating condition, the heat from the water condenser 12 is transferred to the passenger compartment by the blower through the internal heating branch 7 and the heat from the heating core 73. The plate evaporator 15 absorbs heat from the radiator 31. The water in the battery flow channel 53 is subjected to equalization treatment to supplement the heat in the battery flow channel 53 or recover waste heat.

[0035] Sixth operating condition: Please refer to Figure 7 When a vehicle is cold-started in low temperatures, the electric auxiliary heating unit is activated to rapidly heat up the passenger compartment. Once the passenger compartment temperature has risen, this operation is deactivated. Among them, valve port 23 of the ten-way valve 2 is connected to valve port 24 and valve port 25 at the same time. Valve port 25 is also connected to valve port 27. The first three-way valve 52 is opened towards the outlet of the battery flow channel 53. The two outlets of the second three-way valve 74 are both open. The air conditioning module 1 is closed. The electric auxiliary heating unit 72 is turned on to heat. The third pump 71 forms a circulation. The blower delivers the heat of the heating core 73 to the passenger compartment. The second three-way valve 74 adjusts the opening ratio according to the demand to preheat the battery flow channel 53. The water temperature required for the heating core 73 is different from that required for the battery flow channel 53. The water temperature required for the heating core 73 is 80°C, while the preheating water temperature for the battery flow channel 53 is 40°C. Therefore, the second pump 51 forms a uniform temperature circuit and mixes room temperature water at the inlet of the battery flow channel 53 so that the water temperature entering the battery flow channel 53 is close to 40°C.

[0036] Seventh operating condition: Please refer to Figure 8 This operating condition is used to recover heat from the motor to heat the passenger compartment and battery. In this condition, valve port 23 of the ten-way valve 2 is simultaneously connected to valve port 24 and valve port 25, valve port 27 is simultaneously connected to valve port 25 and valve port 210, valve port 26 is connected to valve port 29, the first three-way valve 52 is opened towards the outlet of the battery flow channel 53, both outlets of the second three-way valve 74 are open, the air conditioning module 11 is closed, the blower channel of the passenger compartment heating core 73 is opened, and the battery medium branch 5, the internal heating branch 7, and the electric drive medium branch 4 are mixed and connected through the second pump 51 and the third pump 71, thereby recovering the waste heat of the electric drive to heat the passenger compartment and battery.

[0037] Eighth operating condition: Please refer to Figure 9In this operating condition, waste heat from the electric drive and battery is recovered to heat the passenger compartment. Specifically, valve port 23 of the ten-way valve 2 connects to valve port 24, valve port 27 simultaneously connects to valve port 25 and valve port 210, valve port 26 connects to valve port 29, the first three-way valve 52 opens towards the outlet of the battery flow channel 53, and the second three-way valve 74 opens towards the outlet of valve port 24. The air conditioning module 11 initiates refrigerant circulation, but the electronic expansion valve 14 adaptively adjusts its opening to maintain the compressor 11 at low power, serving only to circulate heat from the plate evaporator 15 in a gradient manner. The heat is transferred to the water condenser 12 by the third pump 71, which then transports the heat from the water condenser 12 to the heating core 73, where it is blown into the passenger compartment by the blower. On the other hand, the second pump 51 draws high-temperature water from the electric drive channel 4 and the battery channel 53 to supply heat to the plate evaporator 15. It should be noted that during this process, the opening of the electronic expansion valve 14 is increased by controlling it so that it does not have a throttling effect. Therefore, the compressor 11 does not need to do a lot of work and acts as a pump to circulate the refrigerant, naturally transporting the heat from the plate evaporator 15 to the water condenser 12 in a gradient.

[0038] Ninth operating condition: Please refer to Figure 10 This operating condition is used for dehumidification in low-temperature environments. In this configuration, valve port 23 of the ten-way valve 2 connects to valve port 24, valve port 27 simultaneously connects to valve port 25 and valve port 210, and valve port 28 and valve port 29 are connected. The first three-way valve 52 opens towards the outlet of the internal refrigeration branch 6, and the second three-way valve 74 opens towards the outlet of valve port 24. The air conditioning module 11 is activated, and the second pump 51 delivers chilled water from the plate evaporator 15 to the internal refrigeration branch 6. A blower then blows air from the passenger compartment towards the internal refrigeration branch. The cooling branch 6 causes the moisture in the air in the passenger compartment to condense upon cooling. On the other hand, the cold water leaving the internal cooling branch 6 is recycled for waste heat through the electric drive channel 41. The air conditioning module 11 uses the water condenser 12 to blow the heat absorbed by the internal cooling branch 6 back into the passenger compartment through the internal heating branch 7. In the air circulation loop in the passenger compartment, the air drawn in first passes through the internal cooling branch 6 for condensation and dehumidification, and then passes through the heating core 73 for heating before being blown back into the passenger compartment. The air blown into the passenger compartment after dehumidification is still high-temperature air.

[0039] Tenth operating condition: Please refer to Figure 11 This operating condition is used for dehumidification in low-temperature environments and for battery waste heat recovery. In this condition, valve port 23 of the ten-way valve 2 is connected to valve port 24, valve port 27 is connected to valve port 25 and valve port 210, valve port 28 and valve port 29 are connected, and both outlets of the first three-way valve 52 are open. Preferably, the outlet opening towards the internal refrigeration branch 6 is 80%, and the outlet opening towards the battery flow channel 53 is 20%. The outlet of the second three-way valve 74 towards valve port 24 is open, and the air conditioning module 11 is turned on. The difference between this operating condition and the ninth operating condition is that 20% of the flow from the first three-way valve 52 is diverted into the battery flow channel 53 for waste heat recovery.

[0040] Example 2

[0041] like Figure 12 As shown, in this embodiment, based on embodiment 1, a second electronic expansion valve 16 is connected in parallel to both ends of the compressor 11.

[0042] In this embodiment, the compressor 11 generates heat through the second electronic expansion valve 16 to heat the passenger cabin, which is used to heat the passenger cabin at extremely low temperatures.

[0043] The embodiments described above are merely examples of several implementations of the present invention, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the present invention. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these modifications and improvements all fall within the scope of protection of the present invention.

Claims

1. A thermal management system for electric vehicles, characterized in that, It includes an air conditioning module (1) and a ten-way valve (2). Each valve port on the ten-way valve (2) is connected to an external heat exchange branch (3), an electric drive medium branch with a pump (4), a battery medium branch (5), an internal cooling branch (6), and an internal heating branch with a pump (7). The air conditioning module (1) includes, according to the medium flow direction, the first flow channel of the compressor (11), the first flow channel of the water condenser (12), and the first flow channel of the plate evaporator (15); The second flow channel of the water condenser (12) is connected in series in the internal heating branch (7). A first three-way valve (52) is provided between one end of the battery medium branch (5), one end of the internal cooling branch (6), and one end of the second flow channel of the plate evaporator (15). The other end is connected to different valve ports of the ten-way valve (2). A second pump (51) is provided at the connection between the second flow channel of the plate evaporator (15) and the valve port. The inlet of the second pump (51) is connected to the valve port.

2. The electric vehicle thermal management system according to claim 1, characterized in that, The ten-way valve (2) includes Valve port 1 (21) and valve port 2 (22) are connected to both ends of the external heat exchange branch (3); valve port 3 (23) and valve port 4 (24) are connected to both ends of the internal heating branch (7); valve port 5 (25) is connected to one end of the battery medium branch (5). Valve port seven (27) is connected to the end of the second pump (51); Valve port 8 (28) is connected to one end of the internal refrigeration branch (6); Valve port nine (29) and valve port ten (210) are connected to both ends of the electric drive medium branch (4).

3. The electric vehicle thermal management system according to claim 2, characterized in that, The battery medium branch (5) includes a battery flow channel (53) connected to valve port five (25). The ten-way valve (2) also includes valve port six (26). The inlet of the battery flow channel (53) is connected to the first three-way valve (52) and valve port six (26), and the outlet is connected to valve port five (25).

4. The electric vehicle thermal management system according to claim 3, characterized in that, The internal heating branch (7) includes, according to the medium flow direction, a third pump (71), a second flow channel of a water condenser (12), an electric auxiliary heating unit (72), and a heating core (73). A bridging branch is also provided between the heating core (73) and the valve port four (24). The bridging branch connects the inlet of the battery flow channel (53) and the outlet of the second pump (51). A throttling pipe (54) is provided between the inlet of the battery flow channel (53) and the outlet of the second pump (51).

5. The electric vehicle thermal management system according to claim 4, characterized in that, A second three-way valve (74) is provided between the heating core (73), valve port four (24) and the bridging branch. The inlet of the second three-way valve (74) is connected to the heating core (73), one outlet is connected to the ten-way valve (2), and the other outlet is connected to the bridging branch.

6. The electric vehicle thermal management system according to claim 5, characterized in that, Both the first three-way valve (52) and the second three-way valve (74) are proportional regulating three-way valves.

7. The electric vehicle thermal management system according to claim 2, characterized in that, The electric drive medium branch (4) includes a connection between a first pump (42) and an electric drive channel (41), the inlet of the first pump (42) being connected to valve port nine (29), and the electric drive channel (41) being connected to valve port ten (210).

8. The electric vehicle thermal management system according to claim 1, characterized in that, The first flow channel inlet of the plate evaporator (15) is provided with a first electronic expansion valve (14) and a drying bottle (13).

9. The electric vehicle thermal management system according to claim 8, characterized in that, The compressor (11) is connected in parallel to two ends with a second electronic expansion valve (16).

10. An electric vehicle thermal management system according to any one of claims 1-9, characterized in that, The refrigerant of the air conditioning module (1) is one of tetrafluoroethane, tetrafluoropropylene or propane.

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