Indirect heat pump type whole vehicle thermal management system of pure electric vehicle

Abstract

The invention discloses a pure electric vehicle indirect type heat pump type whole vehicle heat management system, and relates to the technical field of electric vehicle heat management, the heat management system comprises a refrigerant loop, a motor water loop, a warm air water loop and a battery water loop, a first plate heat exchanger is arranged between the refrigerant loop and the motor water loop for heat coupling, and a second plate heat exchanger is arranged between the motor water loop and the battery water loop; a second plate heat exchanger for heat coupling is arranged between the refrigerant loop and the warm air water loop, and a third plate heat exchanger for heat coupling is arranged between the refrigerant loop and the battery water loop; the motor water loop and the battery water loop can be connected in series through a first communication mechanism, and the warm air water loop and the battery water loop can be connected in series through a second communication mechanism. According to the heat management system, under the high-temperature working condition, secondary condensation can be achieved through the first plate heat exchanger, and the refrigeration performance can be rapidly improved; in an extremely low temperature environment, a heat source is provided for a warm air water loop and a battery water loop by using a motor effect-reducing heating function, and a traditional water PTC heating function is replaced.

Description

Technical Field

[0001] The present invention relates to electric vehicle thermal management, and in particular to an indirect heat pump type whole vehicle thermal management system for a pure electric vehicle. Background Art

[0002] The electric vehicle industry is currently developing rapidly towards a high-voltage platform. In order to solve the problem of long charging time for users, major car companies have also launched 800V super-fast charging functions. However, an important problem accompanying the development of automotive technology is that the huge heat generated by the large current during battery pack charging cannot be dissipated in time at high temperatures, which will seriously affect the battery's fast charging performance; at the same time, the heat generated by fast charging of the battery at low temperatures is dissipated and cannot be fully reused, resulting in a waste of resources.

[0003] Chinese utility model patent CN221090418U discloses an indirect heat pump thermal management system and vehicle. Under low temperatures, it provides a strategy for recovering motor waste heat, making full use of the waste heat of electrical devices such as electric drives and batteries as a heat source for heat pumps. However, the system does not completely eliminate PTC auxiliary heating. Under extremely low temperature conditions where the heat generation of electric drives is limited, the system still needs to use PTC auxiliary heating, so the motor heat utilization cannot cover all ambient temperature ranges. At the same time, under high temperature conditions, the heat dissipation of the refrigerant circuit only relies on the outdoor heat exchanger of the front-end module to complete condensation, and the heat dissipation performance is limited. When dealing with 800V high-voltage platform models, the refrigeration capacity is limited.

[0004] Therefore, it is necessary to develop an indirect heat pump type vehicle thermal management system for pure electric vehicles, which can quickly dissipate heat during 800V high-temperature fast charging and does not require PTC auxiliary heating under extremely low temperature conditions, thereby saving energy while achieving functional integration, reducing costs and weight. Summary of the invention

[0005] The purpose of the present invention is to solve the shortcomings of the above-mentioned background technology and to provide an indirect heat pump type vehicle thermal management system for pure electric vehicles, which can quickly dissipate heat during 800V high-temperature fast charging and does not require PTC auxiliary heating under extremely low temperature conditions. While saving energy, it also realizes function integration and reduces costs and weight.

[0006] The technical solution of the present invention is: a pure electric vehicle indirect heat pump type vehicle thermal management system, characterized in that it includes a refrigerant circuit, a motor water circuit, a heater water circuit, and a battery water circuit.

[0007] A first plate heat exchanger is provided between the refrigerant circuit and the motor water circuit for heat coupling, a second plate heat exchanger is provided between the refrigerant circuit and the heater water circuit for heat coupling, and a third plate heat exchanger is provided between the refrigerant circuit and the battery water circuit for heat coupling;

[0008] A first connecting mechanism is provided between the motor water circuit and the battery water circuit to connect the motor water circuit and the battery water circuit in series, and a second connecting mechanism is provided between the heater water circuit and the battery water circuit to connect the heater water circuit and the battery water circuit in series;

[0009] The motor water circuit includes a cooling water pump, a motor and an MCU, a small three-electric device, and a low-temperature radiator which are connected in series to form a circuit. The first plate heat exchanger is arranged in series between the outlet of the small three-electric device and the inlet of the low-temperature radiator through an internal coolant channel. The first connecting mechanism is arranged on the motor water circuit between the outlet of the low-temperature radiator and the inlet of the cooling water pump.

[0010] The three plate heat exchangers of the present invention are all plate heat exchangers with evaporator functions, and contain two flow channels inside, namely a refrigerant flow channel and a coolant flow channel.

[0011] Preferably, the refrigerant circuit includes a compressor, an electronic expansion valve before an outdoor heat exchanger, an outdoor heat exchanger, a first solenoid valve, an electronic expansion valve before an evaporator, an evaporator and a gas-liquid separator which are sequentially connected in series to form a circuit, and the second plate heat exchanger is arranged in series between the compressor and the electronic expansion valve before the outdoor heat exchanger through an internal refrigerant flow channel.

[0012] Furthermore, the refrigerant circuit also includes an electronic expansion valve and a second solenoid valve. The refrigerant flow channel inside the first plate heat exchanger and the second solenoid valve are connected in series front and back, and the whole formed by the series connection is connected in parallel with the first solenoid valve. The inlet of the electronic expansion valve is connected between the outlet of the refrigerant flow channel of the second plate heat exchanger and the inlet of the electronic expansion valve in front of the outdoor heat exchanger, and the outlet of the electronic expansion valve is connected between the refrigerant flow channel of the first plate heat exchanger and the second solenoid valve.

[0013] Furthermore, the refrigerant circuit also includes a third solenoid valve and an electronic expansion valve before the battery pack. The electronic expansion valve before the battery pack and the refrigerant flow channel inside the third plate heat exchanger are connected in series front and back, and the whole formed in series is connected in parallel with the whole formed by the electronic expansion valve before the evaporator and the evaporator in series. The third solenoid valve is also connected in parallel with the whole formed by the electronic expansion valve before the evaporator and the evaporator.

[0014] Preferably, the battery water circuit comprises a battery cold plate and a battery water pump, and the battery water pump, the battery cold plate and the coolant flow channel inside the third plate heat exchanger are sequentially connected in series to form a circuit;

[0015] The first connecting mechanism is a four-way valve having four valve ports a, b, c, and d. Valve ports a and b of the four-way valve are respectively connected to the low-temperature radiator outlet and the cooling water pump inlet on the motor water circuit, and valve ports c and d of the four-way valve are respectively connected to the battery water pump inlet and the coolant flow channel outlet of the third plate heat exchanger on the battery water circuit.

[0016] Furthermore, when the valve port a of the four-way valve is connected to the valve port b, and the valve port c is connected to the valve port d, the motor water circuit and the battery water circuit each form a loop; when the valve port b of the four-way valve is connected to the valve port d, and the valve port a is connected to the valve port c, the motor water circuit and the battery water circuit are connected in series to form a loop.

[0017] Further, the warm air water circuit includes a warm air water pump and an air conditioner warm air core, and the warm air water pump, the coolant flow channel inside the second plate heat exchanger, and the air conditioner warm air core are connected in series in sequence to form a circuit;

[0018] The second connecting mechanism includes a first three-way valve and a connecting pipe. The first three-way valve is provided with three valve ports e, f and g. The e valve port of the first three-way valve is connected to the outlet of the air conditioning heater core, the f valve port is connected to the inlet of the heater water pump, and the g valve port is connected between the battery cold plate outlet and the coolant inlet of the third plate heat exchanger on the battery water circuit. One end of the connecting pipe is connected between the f valve port of the first three-way valve and the inlet of the heater water pump on the heater water circuit, and the other end is connected between the connection of the g valve port on the battery water circuit and the battery cold plate outlet.

[0019] Furthermore, when the e valve port of the first three-way valve is connected to the f valve port and the g valve port is closed, the warm air water circuit and the battery water circuit each form a loop; when the e valve port of the first three-way valve is connected to the g valve port and the f valve port is closed, the battery water circuit and the warm air water circuit are connected in series to form a loop.

[0020] Preferably, the motor water circuit further includes a second three-way valve for controlling whether the coolant flowing out of the first plate heat exchanger flows through the low-temperature radiator, the second three-way valve is provided with three valve ports h, i and j, the h valve port is connected to the outlet of the coolant flow channel of the first plate heat exchanger, the i valve port is connected to the inlet of the low-temperature radiator, and the j valve port is connected between the outlet of the low-temperature radiator and the first connecting mechanism on the motor water circuit;

[0021] When the valve port h of the second three-way valve is connected to the valve port i and the valve port j is closed, the coolant flowing out of the first plate heat exchanger flows to the first connecting mechanism through the low-temperature radiator; when the valve port h of the second three-way valve is connected to the valve port j and the valve port i is closed, the coolant flowing out of the first plate heat exchanger flows directly to the first connecting mechanism.

[0022] The present invention also provides an automobile comprising a vehicle body and any of the above-mentioned pure electric vehicle indirect heat pump type vehicle thermal management systems, wherein the pure electric vehicle indirect heat pump type vehicle thermal management system is installed on the vehicle body.

[0023] The beneficial effects of the present invention are:

[0024] 1. Under high temperature conditions, the refrigerant circuit is condensed once through the outdoor heat exchanger at the front end of the vehicle body, and then condensed twice through the first plate heat exchanger, which can quickly improve the refrigeration performance. The heat dissipated by the first plate heat exchanger is dissipated into the air by the low-temperature radiator of the motor water circuit, and the heat is quickly dissipated when the heat generated by 800V high-temperature fast charging is too high.

[0025] 2. Under low temperature conditions, the refrigerant circuit and the motor water circuit are coupled by the first plate heat exchanger, which can cover the use of heat pumps in various temperature ranges: under lower ambient temperatures, the original air source heat pump is maintained, and the outdoor heat exchanger of the refrigerant circuit is used to absorb the air heat source to meet the heat pump function; under low temperature conditions, the first plate heat exchanger and the outdoor heat exchanger are used to form a parallel evaporation mode, which improves the recovery of waste heat in the motor water circuit, increases the heating capacity of the heat pump, and makes more full use of the waste heat of electrical devices such as small three electrics, and reduces the ambient temperature threshold for the motor to start the reduced efficiency heating as much as possible, thereby reducing the energy consumption of the whole vehicle.

[0026] 3. In extremely low temperature environments, the motor's reduced-efficiency heating function is used to provide heat sources for the warm air water circuit and the battery water circuit, replacing the traditional water PTC heating function. This saves energy while merging functions, reducing costs and weight. Finally, for some special working conditions, such as heating the passenger compartment under super-fast charging, the solenoid valve is switched to change the circuit mode, and the super-fast heat generated in the battery water circuit can be used to heat the passenger compartment, which also reduces energy consumption.

[0027] 4. In the present invention, the second plate heat exchanger can realize thermal coupling between the refrigerant circuit and the heater water circuit, that is, when the passenger compartment needs to be heated, the refrigerant circuit supplies heat to the heater water circuit; the third plate heat exchanger can realize thermal coupling between the refrigerant circuit and the battery water circuit, whether the battery needs to be cooled down in super fast charging mode or the battery needs to be heated in a low temperature environment, it can be quickly realized through the third plate heat exchanger; when the first connecting mechanism connects the motor water circuit and the battery water circuit in series, the waste heat of the motor water circuit can be recovered to supply heat to the battery water circuit, which meets the battery heating needs and realizes the effective use of heat at the same time; when the second connecting mechanism connects the heater water circuit and the battery water circuit in series, the battery heat can be recovered to supply heat to the heater water circuit, which meets the passenger compartment heating needs and realizes the effective use of heat at the same time.

[0028] 5. In the present invention, the first plate heat exchanger + second solenoid valve in series are connected in parallel with the first solenoid valve in the refrigerant circuit, so it can be selected whether the refrigerant flowing out of the outdoor heat exchanger passes through the first plate heat exchanger according to demand; the third solenoid valve, the series connection of the electronic expansion valve in front of the battery pack + the second plate heat exchanger, and the series connection of the electronic expansion valve in front of the evaporator + the evaporator are in parallel, so it can be selected whether the refrigerant passes through the third plate heat exchanger or the evaporator according to demand. Thus, the refrigerant circuit can be flexibly changed according to the ambient temperature, passenger compartment and battery requirements.

[0029] 6. In the present invention, the first connecting mechanism is a four-way valve. Among the four valve ports a, b, c, and d, valve port ab is connected to the motor water circuit, and valve port cd is connected to the battery water circuit. It is only necessary to control the connection relationship of the four valve ports to quickly realize the separate circulation or series circulation of the motor water circuit and the battery water circuit. When connected in series, it is convenient to use the residual heat of the motor to heat the battery or dissipate the residual heat of the battery from the motor water circuit to the outside.

[0030] 7. In the present invention, the second connecting mechanism is a first three-way valve and a connecting pipe. Among the three valve ports e, f and g, valve port ef is connected to the heater water circuit, and valve port g is connected to the battery water circuit. When valve port eg is connected and valve port f is closed, the connecting pipe introduces the coolant of the battery water circuit into the heater water circuit and then returns to the battery water circuit through valve port g, thereby realizing the series connection of the battery water circuit and the heater water circuit, making it convenient to use the heat generated by the battery to heat the heater core.

[0031] 8. In the present invention, the second three-way valve can control whether the coolant flowing out of the first plate heat exchanger flows through the low-temperature radiator through the connection relationship of the three valve ports h, i, and j. In a low-temperature environment, the motor water circuit will generate heat for the motor, MCU, and the electrical body absorbed by the small three-way valve to provide a heat source for the refrigerant. At this time, there is no need to dissipate heat outward through the low-temperature radiator, so that the coolant in the motor water circuit can flow quickly and efficiently. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 Schematic diagram of the system structure of the present invention

[0033] Figure 2 Schematic diagram of the system in Example 1 under high temperature - passenger cabin cooling - no battery demand - electric drive heat dissipation mode

[0034] Figure 3 Schematic diagram of the system in Example 1 under high temperature super fast charging - passenger compartment cooling - battery cooling - electric drive heat dissipation mode

[0035] Figure 4 Schematic diagram of the system in Example 2 under the low-temperature fast charging - passenger compartment heating - battery heating - electric drive no demand mode

[0036] Figure 5 Schematic diagram of the system in Example 2 under the low-temperature fast charging - passenger compartment heating - battery heating - electric drive waste heat recovery mode

[0037] Figure 6 Example 2: Extremely low temperature fast charging - passenger compartment heating - battery heating - electric drive motor reduced efficiency heating

[0038] Figure 7 Schematic diagram of the system in Example 2, low-temperature fast charging - passenger compartment heating - battery cooling (lower temperature) - electric drive no demand mode

[0039] Figure 8 This is a schematic diagram of the system in Example 2, low-temperature fast charging - passenger compartment heating - battery cooling (higher temperature) - electric drive no-demand mode.

[0040] Among them: 100-refrigerant circuit 200-motor water circuit 300-heating water circuit 400-battery water circuit 500-connecting pipe 1-compressor 2-second plate heat exchanger 3-electronic expansion valve in front of outdoor heat exchanger 4-outdoor heat exchanger 5-first solenoid valve 6-electronic expansion valve 7-second solenoid valve 8-third solenoid valve 9-gas-liquid separator 10-electronic expansion valve in front of evaporator 11-evaporator 12-electronic expansion valve in front of battery pack 13-third plate heat exchanger 14-air conditioning heater core 15-first three-way valve 16-heating water pump 17-first expansion kettle 18-battery water pump 19-battery cold plate 20-four-way valve 21-cooling water pump 22-motor and MCU (MCU refers to motor controller) 23-small three electrics 24-first plate heat exchanger 25-second three-way valve 26-low-temperature radiator 27-second expansion kettle 28-electronic fan 29-blower. DETAILED DESCRIPTION

[0041] The embodiments of the present invention are described in detail below, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present invention, and should not be construed as limiting the present invention. The three plate heat exchangers of the present invention (the first plate heat exchanger 24, the second plate heat exchanger 2, and the third plate heat exchanger 13) are all plate heat exchangers with evaporator functions, and contain two flow channels inside for circulating refrigerant and coolant, respectively, which can also be called refrigerant flow channels and coolant flow channels. Figure 2-8 In the figure, the thick black line shows the refrigerant / coolant flow path, and the flow direction is from front to back.

[0042] like Figure 1 As shown, this embodiment provides an indirect heat pump type vehicle thermal management system for a pure electric vehicle, including a refrigerant circuit 100, a motor water circuit 200, a heater water circuit 300, and a battery water circuit 400.

[0043] A first plate heat exchanger 24 is provided between the refrigerant circuit 100 and the motor water circuit 200 for heat coupling, a second plate heat exchanger 2 is provided between the refrigerant circuit 100 and the heater water circuit 300 for heat coupling, and a third plate heat exchanger 13 is provided between the refrigerant circuit 100 and the battery water circuit 400 for heat coupling;

[0044] A first connecting mechanism is provided between the motor water circuit 200 and the battery water circuit 400, which can connect the motor water circuit 200 and the battery water circuit 400 in series. A second connecting mechanism is provided between the heater water circuit 300 and the battery water circuit 400, which can connect the heater water circuit 300 and the battery water circuit 400 in series.

[0045] The specific structure of the motor water circuit 200 is as follows: the motor water circuit 200 includes a cooling water pump 21, a motor and MCU 22, a small three electric devices 23, and a low-temperature radiator 26. The first plate heat exchanger 24 is arranged in series between the outlet of the small three electric devices 23 and the inlet of the low-temperature radiator 26 through an internal coolant channel. That is, the cooling water pump 21, the motor and MCU 22, the small three electric devices 23, the coolant channel of the first plate heat exchanger 24, and the low-temperature radiator 26 on the motor water circuit 200 are sequentially connected in series to form a loop.

[0046] The specific structure of the refrigerant circuit 100 is as follows: the refrigerant circuit 100 includes a compressor 1, an electronic expansion valve 3 before the outdoor heat exchanger, an outdoor heat exchanger 4, a first solenoid valve 5, an electronic expansion valve 10 before the evaporator, an evaporator 11 and a gas-liquid separator 9 which are sequentially connected in series to form a circuit, and the second plate heat exchanger 2 is arranged in series between the outlet of the compressor 1 and the inlet of the electronic expansion valve 3 before the outdoor heat exchanger through a refrigerant flow channel. That is, the compressor 1, the refrigerant flow channel of the second plate heat exchanger 2, the electronic expansion valve 3 before the outdoor heat exchanger, the outdoor heat exchanger 4, the first solenoid valve 5, the electronic expansion valve 10 before the evaporator, the evaporator 11 and the gas-liquid separator 9 are sequentially connected in series to form a circuit.

[0047] The refrigerant circuit 100 further includes an electronic expansion valve 6 and a second solenoid valve 7. The refrigerant flow path inside the first plate heat exchanger 24 is connected in series with the second solenoid valve 7, and the whole formed in series is connected in parallel with the first solenoid valve 5. The inlet of the electronic expansion valve 6 is connected between the outlet of the refrigerant flow path of the second plate heat exchanger 2 on the refrigerant circuit 100 and the inlet of the electronic expansion valve 3 before the outdoor heat exchanger, and the outlet of the electronic expansion valve 6 is connected between the outlet of the refrigerant flow path of the first plate heat exchanger 24 and the inlet of the second solenoid valve 7. The specific connection mode of the refrigerant flow path inside the first plate heat exchanger 24 and the second solenoid valve 7 in series is as follows: the inlet of the refrigerant flow path of the first plate heat exchanger 24 is connected between the outlet of the outdoor heat exchanger 4 and the inlet of the first solenoid valve 5 on the refrigerant circuit 100, the outlet of the refrigerant flow path of the first plate heat exchanger 24 is connected to the inlet of the second solenoid valve 7, and the outlet of the second solenoid valve 7 is connected between the outlet of the first solenoid valve 5 on the refrigerant circuit 100 and the inlet of the electronic expansion valve 10 before the evaporator.

[0048] By controlling the first solenoid valve 5, the electronic expansion valve 6, and the second solenoid valve 7, the refrigerant flowing out of the second plate heat exchanger 2 can flow backward through the electronic expansion valve 3, the outdoor heat exchanger 4, and the first solenoid valve 5 in front of the outdoor heat exchanger on the main circuit (at this time, the first solenoid valve 5 is open, and the electronic expansion valve 6 and the second solenoid valve 7 are closed); or flow backward through the electronic expansion valve 3, the outdoor heat exchanger 4, the first plate heat exchanger 24, and the second solenoid valve 7 in front of the outdoor heat exchanger (at this time, the first solenoid valve 5 and the electronic expansion valve 6 are closed, and the second solenoid valve 7 is open); or flow backward through the electronic expansion valve 6 and the second solenoid valve 7 (at this time, the first solenoid valve 5 is closed, and the electronic expansion valve 6 and the second solenoid valve 7 are opened); or be divided into two parallel paths - one path passes through the electronic expansion valve 3+outdoor heat exchanger 4 in front of the outdoor heat exchanger, and the other path passes through the electronic expansion valve 6+first plate heat exchanger 24, and after merging, flows backward through the first solenoid valve 5 (at this time, the first solenoid valve 5 and the electronic expansion valve 6 are opened, and the second solenoid valve 7 is closed). The refrigerant flow direction in the first plate heat exchanger 24 can be changed according to demand and is controlled by the electronic expansion valve 6 that adjusts the pressure difference on the pipeline. When the electronic expansion valve 6 is opened to throttle and release pressure and the second solenoid valve 7 is closed, the refrigerant flows from the outlet of the refrigerant flow channel of the first plate heat exchanger 24 to the inlet (the outlet and inlet are only for the convenience of referring to the two ends of the refrigerant flow channel of the plate heat exchanger 24, i.e., one end and the other end, and are not intended to limit the internal refrigerant flow direction). In other cases, the refrigerant flows from the inlet of the refrigerant flow channel to the outlet when passing through the first plate heat exchanger 24.

[0049] The refrigerant circuit 100 further includes a third solenoid valve 8 and an electronic expansion valve 12 in front of the battery pack. The electronic expansion valve 12 in front of the battery pack and the flow passage of the refrigerant flowing inside the third plate heat exchanger 13 are connected in series front and back, and the whole formed in series is connected in parallel with the whole formed by the electronic expansion valve 10 in front of the evaporator and the evaporator 11. The third solenoid valve 8 is also connected in parallel with the whole formed by the electronic expansion valve 10 in front of the evaporator and the evaporator 11. That is, the third solenoid valve 8, the series whole of the electronic expansion valve 12 in front of the battery pack + the second plate heat exchanger 13, and the series whole of the electronic expansion valve 10 in front of the evaporator + the evaporator 11 in the refrigerant circuit are in a parallel relationship.

[0050] The specific connection mode of the third solenoid valve 8 is: the inlet is connected to the outlet connection of the second solenoid valve 7 on the refrigerant circuit 100 (the inlet can also be connected between the outlet connection of the second solenoid valve 7 on the refrigerant circuit 100 and the inlet of the electronic expansion valve 10 before the evaporator), and the outlet of the third solenoid valve 8 is connected between the outlet of the evaporator 11 and the inlet of the gas-liquid separator 9 on the refrigerant circuit 100. The specific connection mode of the electronic expansion valve 12 before the battery pack + the second plate heat exchanger 13 is: the inlet of the electronic expansion valve 12 before the battery pack is connected between the inlet connection of the third solenoid valve 8 on the refrigerant circuit 100 and the inlet of the electronic expansion valve 10 before the evaporator, the outlet of the electronic expansion valve 12 before the battery pack is connected to the refrigerant flow channel inlet of the second plate heat exchanger 13, and the refrigerant flow channel outlet of the second plate heat exchanger 13 is connected between the outlet of the evaporator 11 and the outlet connection of the third solenoid valve 8 on the refrigerant circuit 100. Therefore, by controlling the third solenoid valve 8, the electronic expansion valve 10 before the evaporator, and the electronic expansion valve 12 before the battery pack, the refrigerant can flow into the gas-liquid separator 9 through the electronic expansion valve 10 before the evaporator + the evaporator 11 in the main circuit, or directly flow into the separator 9 from the third solenoid valve 8, or flow into the separator 9 through the electronic expansion valve 12 before the battery pack + the second plate heat exchanger 13.

[0051] The specific structure of the battery water loop 400 is as follows: it includes a battery cold plate 19 and a battery water pump 18 , and the battery water pump 18 , the battery cold plate 19 and the internal coolant flow channel of the third plate heat exchanger 13 are sequentially connected in series to form a loop.

[0052] The specific structure of the first connecting mechanism is: a four-way valve 20 with four valve ports a, b, c, and d. The valve ports a and b of the four-way valve 20 are respectively connected to the outlet of the low-temperature radiator 26 and the inlet of the cooling water pump 21 on the motor water circuit 200, and the valve ports c and d of the four-way valve 20 are respectively connected to the inlet of the battery water pump 18 and the outlet of the coolant flow channel of the third plate heat exchanger 13 on the battery water circuit 400. When the valve port a of the four-way valve 20 is connected to the valve port b, and the valve port c is connected to the valve port d, the motor water circuit 200 and the battery water circuit 400 form a circuit respectively. This connection method is suitable for when the battery has a heating demand (air source heat pump) or a cooling demand; when the valve port b of the four-way valve 20 is connected to the valve port d, and the valve port a is connected to the valve port c, the motor water circuit 200 and the battery water circuit 400 are connected in series to form a circuit. This connection method is suitable for when the battery has a heating demand (waste heat recovery or motor efficiency reduction heating).

[0053] The specific structure of the warm air water circuit 300 is: it includes a warm air water pump 16, an air conditioning warm air core 14, and the warm air water pump 16, the coolant flow channel of the second plate heat exchanger 2, and the air conditioning warm air core 14 are connected in series in sequence to form a circuit.

[0054] The specific structure of the second connecting mechanism is as follows: it includes a first three-way valve 15 and a connecting pipe 500. The first three-way valve 15 has three valve ports e, f, and g. The e valve port of the first three-way valve 15 is connected to the outlet of the air conditioning warm air core 14, the f valve port is connected to the inlet of the warm air water pump 16, and the g valve port is connected between the outlet of the battery cold plate 19 on the battery water circuit 400 and the inlet of the coolant flow channel of the third plate heat exchanger 13. One end (the outlet end) of the connecting pipe 500 is connected between the f valve port of the first three-way valve 15 on the warm air water circuit 300 and the inlet of the warm air water pump 16, and the other end (the inlet end) is connected between the connection of the g valve port on the battery water circuit 400 and the outlet of the battery cold plate 19. When the valve port eg of the first three-way valve 15 is connected and the valve port f is closed, the battery water circuit 400 and the heater water circuit 300 are connected in series to form a circuit. This connection mode is applicable to the following two situations: ① When the compressor is not started at extremely low temperature, the passenger compartment and the battery are heated by motor reduction heating; ② At a relatively low temperature, the motor reduction heating is not turned on, and the battery needs to be heated. In addition to the above two situations, when the valve port e of the first three-way valve 15 is connected to the valve port f and the valve port g is closed, the heater water circuit 300 and the battery water circuit 400 each form a circuit.

[0055] When the bd valve port and the ac valve port of the four-way valve 20 are connected, and the eg valve port of the first three-way valve 15 is connected and the f valve port is closed, the motor water circuit 200 + the warm air water circuit 300 + the battery water circuit 400 are connected in series to form a large circuit, which is suitable for supplying heat to the warm air water circuit 300 and the battery water circuit 400 through the motor of the motor water circuit 200 and the MCU22 reduced efficiency heating function during extremely low temperature fast charging.

[0056] As a preferred example, a second three-way valve 25 for controlling whether the coolant flowing out of the first plate heat exchanger 24 flows through the low-temperature radiator 26 may also be provided on the motor water circuit 200. The second three-way valve 25 is provided with three valve ports h, i, and j. The h valve port is connected to the coolant flow channel outlet of the first plate heat exchanger 24, the i valve port is connected to the inlet of the low-temperature radiator 26, and the j valve port is connected between the outlet of the low-temperature radiator 26 and the a valve port of the four-way valve 20; when the h valve port of the first three-way valve 25 is connected to the i valve port and the j valve port is closed, the coolant flowing out of the first plate heat exchanger 24 flows to the a valve port of the four-way valve 20 through the low-temperature radiator 26; when the h valve port of the second three-way valve 25 is connected to the j valve port and the i valve port is closed, the coolant flowing out of the first plate heat exchanger 24 flows directly to the a valve port of the four-way valve 20.

[0057] In this embodiment, the outdoor heat exchanger 4 and the low-temperature radiator 26 are both arranged in the front end module of the vehicle body. An electronic fan 28 is provided at the rear of the space of the outdoor heat exchanger 4 for heat exchange with the environment. The evaporator 11 is located in the air-conditioning box, and a blower 29 is provided on one side for controlling the air intake of the passenger compartment. A first expansion kettle 17 is provided on the warm air water circuit 300 to ensure the normal operation of the coolant, and a second expansion kettle 27 is provided on the motor water circuit 200 to ensure the normal operation of the coolant.

[0058] The thermal management system in the present invention will realize multiple modes of passenger compartment cooling / heating, battery cooling / heating, electric drive waste heat recovery / electrode reduced efficiency heating under different temperature environments according to different needs during the use of the whole vehicle, and its circuits can be combined in various ways according to actual needs.

[0059] Example 1

[0060] The following are typical operating conditions in high temperature environments.

[0061] The first typical use condition of the present invention is as follows Figure 2 As shown, under high temperature conditions, if the passenger compartment requires cooling and the battery has no demand, the compressor 1 starts, compresses the refrigerant (coolant) into a high-temperature and high-pressure gas, and enters the outdoor heat exchanger 4 through the third plate heat exchanger 2 and the electronic expansion valve 3 before the outdoor heat exchanger for condensation. At the same time, the first solenoid valve 5 is opened and the second solenoid valve 7 is closed. After condensation, the liquid refrigerant with supercooling is depressurized and expanded into a low-temperature and low-pressure gas-liquid two-phase state at the electronic expansion valve 10 before the evaporator, evaporates and absorbs heat in the evaporator 11, and then returns to the compressor 1 through the gas-liquid separator 9 for circulation. Among them, the vehicle speed and the electronic fan 28 ensure sufficient air intake for the front-end module, and fully cool and condense the refrigerant in the outdoor condenser 4. In the motor water circuit, under high temperature environment, the electric drive also has heat dissipation requirements. Driven by the motor water pump 21, the coolant absorbs the heat of the small three-electric 23, the motor and the MCU 22 respectively, and flows to the low-temperature radiator 26 of the front-end module through the h and i valve ports of the second three-way valve 25, dissipates heat to the air, and then circulates through the a and b valve ports of the four-way valve 20 and returns to the first plate heat exchanger 24. Under this working condition, the battery has no heat dissipation requirements, and the heat dissipation performance of the outdoor heat exchanger 4 can meet the cooling requirements of the passenger compartment, so there is no need to open the second solenoid valve 7 for secondary condensation of the refrigerant.

[0062] When the outdoor heat exchanger 4 alone cannot meet the heat dissipation performance requirements due to the huge heat generated by super-fast charging, it will operate in accordance with the next second operating condition.

[0063] The second typical use condition of the present invention is as follows Figure 3As shown, in the high-temperature super-fast charging mode, if the passenger compartment requires cooling and the battery requires cooling, the compressor 1 starts, and the compressed refrigerant is converted into a high-temperature and high-pressure gas, which enters the outdoor heat exchanger 4 through the third plate heat exchanger 2 and the electronic expansion valve 3 in front of the outdoor heat exchanger for the first condensation. The first solenoid valve 5 is closed, the electronic expansion valve 6 is closed, and the second solenoid valve 7 is opened. The condensed liquid into a low-temperature and high-pressure liquid enters the first plate heat exchanger 24 for secondary condensation. After condensing into a liquid refrigerant with a supercooling degree, it flows to the evaporator 11 and the second plate heat exchanger 13 in the air-conditioning box through the opened second solenoid valve 7 (the third solenoid valve 8 is closed at this time). Before this, both refrigerants need to expand and atomize through the electronic expansion valve 10 in front of the evaporator and the electronic expansion valve 12 in front of the battery pack, respectively, to become a low-temperature and low-pressure gas-liquid two-phase state, evaporate and absorb heat in the evaporator 11 and the third plate heat exchanger 13, respectively, and then converge through the gas-liquid separator 9 to return to the compressor 1 for circulation. The heat lost by the refrigerant that is condensed twice at the first plate heat exchanger 24 will be absorbed by the coolant in the motor water circuit, and driven by the motor water pump 21, it will absorb the heat of the small three-electric 23, the motor and the MCU 22 respectively, and flow to the low-temperature radiator 26 of the front-end module through the h and i valve ports of the second three-way valve 25, dissipate heat into the air, and then circulate through the a and b valve ports of the four-way valve 20, return to the first plate heat exchanger 24 to absorb the heat of the refrigerant circuit 100 again, and achieve the effect of secondary condensation. The refrigerant evaporated from the third plate heat exchanger 13 will absorb the heat in the battery water circuit on the other side of the cold plate, and driven by the battery water pump 18, the coolant in the battery water circuit will be kept circulating continuously, absorbing the huge heat generated by the super-fast charging process of the battery, and realizing the battery cooling function.

[0064] Example 2

[0065] The following are typical operating conditions in low temperature environments.

[0066] The third typical use condition of the present invention is as follows Figure 4 As shown, in the low temperature fast charging mode, if the passenger cabin needs to be heated and the battery needs to be heated, the compressor 1 starts, compresses the refrigerant into a high temperature and high pressure gas, condenses through the second plate heat exchanger 2, and becomes a low temperature and high pressure liquid, and then the electronic expansion valve 3 is depressurized and expanded in front of the outdoor heat exchanger, and becomes a two-phase refrigerant that enters the outdoor heat exchanger 4 to absorb heat and evaporate, and then flows through the first solenoid valve 5 and the third solenoid valve 8 in sequence to enter the gas-liquid separator 9, and finally flows back to the compressor. At the same time, the warm air water circuit 300 + battery water circuit 400 are connected in series: the warm air water pump 16 in the warm air water circuit 300 drives the coolant to flow through the second plate heat exchanger 2 to absorb heat, and then flows through the warm air core 14, the eg valve port of the first three-way valve 15, the plate heat exchanger 13, and finally to the battery cold plate 19, and returns to the warm air water circuit 300 through the connecting pipe 500, and the blower 29 drives the air in the passenger cabin to flow through the warm air core 14 with heat and then enter the passenger cabin to achieve the heating function.

[0067] The fourth typical use condition of the present invention is as follows Figure 5 As shown, in the low-temperature fast charging mode, if the passenger compartment needs to be heated and the battery needs to be heated, the compressor 1 is started, and the compressed refrigerant is turned into a high-temperature and high-pressure gas, which is condensed through the second plate heat exchanger 2 and becomes a low-temperature and high-pressure liquid. Then, it is depressurized and expanded at the electronic expansion valve 3 and the electronic throttle valve 6 in front of the outdoor heat exchanger, respectively, and becomes a two-phase refrigerant, which enters the outdoor heat exchanger 4 and the first plate heat exchanger 24 to absorb heat and evaporate. After converging, it flows through the first solenoid valve 5 and the third solenoid valve 8 in turn, enters the gas-liquid separator 9 (the second solenoid valve 7 is closed at this time), and finally flows back to the compressor 1. Among them, the heat source of evaporation heat absorption at the outdoor heat exchanger 4 mainly comes from the outdoor air driven by the electronic fan 28 to flow through the front-end module, while the first plate heat exchanger 24 is driven by the motor water pump 21 to drive the coolant through the small three electrics 23, the motor and the MCU 22 to absorb the heat of the electrical body to provide a heat source for the evaporation of the refrigerant in the first plate heat exchanger 24. After the coolant is heated, it returns to the motor water pump 21 through the hj valve port of the second three-way valve 25 and the ab valve port of the four-way valve. At the same time, the warm air water circuit 300 + battery water circuit 400 are connected in series: the warm air water pump 16 in the warm air water circuit drives the coolant to flow through the second plate heat exchanger 2 to absorb heat, and then flows through the warm air core 14, the eg valve port of the first three-way valve 15, the third plate heat exchanger 13, the cd valve port of the four-way valve 20 and finally to the battery cold plate 19. The blower 29 drives the passenger compartment air to flow through the warm air core 14 with heat and then enters the passenger compartment to achieve the heating function. Here, the motor water circuit 200 and the refrigerant circuit 100 are thermally coupled through the first plate heat exchanger 24, which makes fuller use of the waste heat of electrical components such as the three small electric appliances, lowers the ambient temperature threshold for starting the motor's reduced-efficiency heating as much as possible, and reduces the energy consumption of the entire vehicle (if in driving conditions, the waste heat of the motor can also be further recycled and utilized, the principle is similar, and will not be elaborated here).

[0068] The fifth typical use condition of the present invention is as follows Figure 6As shown, in an extremely low temperature environment, if the passenger cabin needs to be heated and the battery needs to be heated, the compressor 1 does not start, the refrigerant circuit 100 does not work, and only the heater water circuit 300+battery water circuit 400+motor water circuit 200 are connected in series, and the heater water pump 16 and the motor water pump 21 drive the coolant to flow through the second plate heat exchanger 2, the heater core 14, the eg valve port of the first three-way valve 15, the third plate heat exchanger 13, the db interface of the four-way valve 20, the motor water pump 21, the motor and MCU 22, the small three-electric 23, the first plate heat exchanger 24, the hj valve port of the second three-way water valve 25, the ac valve port of the four-way valve, the battery water pump 18, the battery cold plate 19, and finally return to the heater water pump 16 through the connecting pipe 500. The coolant is heated to the target temperature through the motor and the reduced-efficiency heating function of the MCU 22, and the passenger compartment heating and battery heating functions are realized at the heater core 14 and the battery cold plate 19 respectively. This cycle is a series heating mode.

[0069] The sixth typical use condition of the present invention is as follows Figure 7 As shown, in the low-temperature super-fast charging condition, if the passenger compartment needs to be heated and the battery needs to be cooled, the compressor 1 starts, compresses the refrigerant into a high-temperature and high-pressure gas, condenses through the second plate heat exchanger 2, and becomes a low-temperature and high-pressure liquid, and then flows through the electronic throttle valve 6 and the second solenoid valve 7 (the first solenoid valve 5 is closed), and is depressurized and expanded at the electronic expansion valve 12 in front of the battery pack, and becomes a two-phase refrigerant. It absorbs heat and evaporates through the third plate heat exchanger 13, then enters the gas-liquid separator 9, and finally flows back to the compressor 1. Among them, during super-fast charging, the battery will generate a large amount of heat that dissipates from the battery cold plate 19 into the coolant. The coolant is driven by the battery water pump 18 and flows into the plate heat exchanger 13 to provide a heat source for the evaporation of the refrigerant, and then returns to the battery water pump 18 from the DC valve port of the four-way valve 20, forming an internal cycle. The heating water circuit 300 refers to the previous working condition. The heating water pump 16 drives the coolant to absorb heat at the second plate heat exchanger 2, and then enters the heating state 14 and the ef valve port of the first three-way water valve 15 to form an internal circulation to complete the heating of the passenger compartment. This function mode is applicable when the battery temperature is within the safe range. If the battery temperature continues to rise due to super fast charging, the BD valve port and AC valve port of the four-way valve 20 need to be opened to allow the coolant to form a large circulation in the motor water circuit and the battery water circuit. Figure 8 As shown (motor water circuit + battery water circuit are connected in series, and the heater water circuit circulates internally independently).

[0070] The above shows and describes the basic principles, main features and advantages of the present invention. It should be understood by those skilled in the art that the present invention is not limited to the above embodiments, and the above embodiments and descriptions are only for explaining the principles of the invention. The present invention may be subject to various changes and improvements without departing from the spirit and scope of the present invention, and these changes and improvements fall within the scope of the present invention to be protected. The scope of protection of the present invention is defined by the attached claims and their equivalents.

Claims

1. A pure electric vehicle indirect heat pump type vehicle thermal management system, characterized in that: It comprises a refrigerant circuit (100), a motor water circuit (200), a heater water circuit (300), and a battery water circuit (400). A first plate heat exchanger (24) is provided between the refrigerant circuit (100) and the motor water circuit (200) for thermal coupling, a second plate heat exchanger (2) is provided between the refrigerant circuit (100) and the heater water circuit (300) for thermal coupling, and a third plate heat exchanger (13) is provided between the refrigerant circuit (100) and the battery water circuit (400) for thermal coupling; A first connecting mechanism is provided between the motor water circuit (200) and the battery water circuit (400) and is capable of connecting the motor water circuit (200) and the battery water circuit (400) in series, and a second connecting mechanism is provided between the heater water circuit (300) and the battery water circuit (400) and is capable of connecting the heater water circuit (300) and the battery water circuit (400) in series; The motor water circuit (200) comprises a cooling water pump (21), a motor and an MCU (22), a small three-electric device (23), and a low-temperature radiator (26) which are sequentially connected in series to form a circuit; the first plate heat exchanger (24) is arranged in series between an outlet of the small three-electric device (23) and an inlet of the low-temperature radiator (26) through an internal coolant channel; and the first connecting mechanism is arranged on the motor water circuit (200) between the outlet of the low-temperature radiator (26) and the inlet of the cooling water pump (21).

2. The indirect heat pump type vehicle thermal management system for a pure electric vehicle as claimed in claim 1, characterized in that: The refrigerant circuit (100) comprises a compressor (1), an electronic expansion valve (3) before an outdoor heat exchanger, an outdoor heat exchanger (4), a first solenoid valve (5), an electronic expansion valve (10) before an evaporator, an evaporator (11) and a gas-liquid separator (9) which are sequentially connected in series to form a circuit, and the second plate heat exchanger (2) is arranged in series between the compressor (1) and the electronic expansion valve (3) before the outdoor heat exchanger via an internal refrigerant flow channel.

3. The indirect heat pump type vehicle thermal management system for a pure electric vehicle as claimed in claim 2, characterized in that: The refrigerant circuit (100) also includes an electronic expansion valve (6) and a second solenoid valve (7); the refrigerant flow path inside the first plate heat exchanger (24) and the second solenoid valve (7) are connected in series front and back, and the whole formed by the series connection is connected in parallel with the first solenoid valve (5); the inlet of the electronic expansion valve (6) is connected between the outlet of the refrigerant flow path of the second plate heat exchanger (2) and the inlet of the electronic expansion valve (3) in front of the outdoor heat exchanger, and the outlet of the electronic expansion valve (6) is connected between the refrigerant flow path of the first plate heat exchanger (24) and the second solenoid valve (7).

4. The indirect heat pump type vehicle thermal management system for a pure electric vehicle as claimed in claim 3, characterized in that: The refrigerant circuit (100) further comprises a third solenoid valve (8) and an electronic expansion valve (12) in front of the battery pack. The electronic expansion valve (12) in front of the battery pack and the refrigerant flow path inside the third plate heat exchanger (13) are connected in series front and back, and the whole formed in series is connected in parallel with the whole formed in series with the electronic expansion valve (10) in front of the evaporator and the evaporator (11). The third solenoid valve (8) is also connected in parallel with the whole formed by the electronic expansion valve (10) in front of the evaporator and the evaporator (11).

5. The indirect heat pump type vehicle thermal management system for a pure electric vehicle as claimed in claim 1, characterized in that: The battery water circuit (400) comprises a battery cold plate (19) and a battery water pump (18), wherein the battery water pump (18), the battery cold plate (19) and the internal coolant flow channel of the third plate heat exchanger (13) are sequentially connected in series to form a circuit; The first connecting mechanism is a four-way valve (20) having four valve ports a, b, c, and d. The valve ports a and b of the four-way valve (20) are respectively connected to the outlet of the low-temperature radiator (26) and the inlet of the cooling water pump (21) on the motor water circuit (200). The valve ports c and d of the four-way valve (20) are respectively connected to the inlet of the battery water pump (18) and the outlet of the coolant flow channel of the third plate heat exchanger (13) on the battery water circuit (400).

6. The indirect heat pump type vehicle thermal management system for a pure electric vehicle as claimed in claim 5, characterized in that: When the valve port a of the four-way valve (20) is connected to the valve port b, and the valve port c is connected to the valve port d, the motor water circuit (200) and the battery water circuit (400) each form a circuit; when the valve port b of the four-way valve (20) is connected to the valve port d, and the valve port a is connected to the valve port c, the motor water circuit (200) and the battery water circuit (400) are connected in series to form a circuit.

7. The indirect heat pump type vehicle thermal management system for a pure electric vehicle as claimed in claim 5, characterized in that: The warm air water circuit (300) comprises a warm air water pump (16) and an air conditioner warm air core (14), wherein the warm air water pump (16), the internal coolant flow channel of the second plate heat exchanger (2), and the air conditioner warm air core (14) are sequentially connected in series to form a circuit; The second connecting mechanism comprises a first three-way valve (15) and a connecting pipe (500), wherein the first three-way valve (15) is provided with three valve ports e, f and g, wherein the valve port e of the first three-way valve (15) is connected to the outlet of the air conditioning heater core (14), the valve port f is connected to the inlet of the heater water pump (16), and the valve port g is connected between the outlet of the battery cold plate (19) on the battery water circuit (400) and the coolant inlet of the third plate heat exchanger (13), and one end of the connecting pipe (500) is connected between the valve port f of the first three-way valve (15) on the heater water circuit (300) and the inlet of the heater water pump (16), and the other end is connected between the connection of the valve port g on the battery water circuit (400) and the outlet of the battery cold plate (19).

8. The indirect heat pump type vehicle thermal management system for a pure electric vehicle as claimed in claim 7, characterized in that: When the valve port e of the first three-way valve (15) is connected to the valve port f and the valve port g is closed, the warm air water circuit (300) and the battery water circuit (400) each form a circuit; when the valve port e of the first three-way valve (15) is connected to the valve port g and the valve port f is closed, the battery water circuit (400) and the warm air water circuit (300) are connected in series to form a circuit.

9. The indirect heat pump type vehicle thermal management system for a pure electric vehicle as claimed in claim 1, characterized in that: The motor water circuit (200) further comprises a second three-way valve (25) for controlling whether the coolant flowing out of the first plate heat exchanger (24) flows through the low-temperature radiator (26), the second three-way valve (25) being provided with three valve ports h, i and j, the valve port h being connected to the outlet of the coolant flow channel of the first plate heat exchanger (24), the valve port i being connected to the inlet of the low-temperature radiator (26), and the valve port j being connected between the outlet of the low-temperature radiator (26) and the first connecting mechanism on the motor water circuit (200); When the h valve port of the second three-way valve (25) is connected to the i valve port and the j valve port is closed, the coolant flowing out of the first plate heat exchanger (24) flows to the first connecting mechanism through the low-temperature radiator (26); when the h valve port of the second three-way valve (25) is connected to the j valve port and the i valve port is closed, the coolant flowing out of the first plate heat exchanger (24) flows directly to the first connecting mechanism.

10. An automobile, characterized in that: It comprises a vehicle body and a pure electric vehicle indirect heat pump type vehicle thermal management system as claimed in any one of claims 1 to 9, wherein the pure electric vehicle indirect heat pump type vehicle thermal management system is installed on the vehicle body.

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