Indirect heat pump heat management system for new energy automobile

Abstract

The invention relates to the technical field of new energy automobile heat management, and belongs to an indirect heat pump heat management system for a new energy automobile. Battery outlet water and warm core outlet water are converged and then shunted through a waterway integration mode of a five-way valve and a proportional three-way valve, and the flow is distributed through the proportional three-way valve; the mixed water enters the battery to control the water inlet temperature of the battery, so that a water-water heat exchanger can be saved, and the effects of reducing cost and improving efficiency are achieved; on the aspect of the agent side, a large-diameter electronic expansion valve is arranged at an outlet of the water-cooling condenser, the internal flow and state of the water-cooling condenser are actively controlled by adjusting the opening degree of the large-diameter electronic expansion valve, the supercooling degree can be increased, the superheat degree can be restrained, the heat exchange capacity and the accurate control capacity can be enhanced, and heating and dehumidification outlet air temperature control in spring and autumn can be better achieved.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of new energy vehicle thermal management technology, and belongs to an indirect heat pump thermal management system for a new energy vehicle. BACKGROUND

[0002] The existing thermal management integrated module integrates the water circuit through a five-way valve and a proportional three-way valve. In the battery heating working condition, the water-water heat exchanger is relied on for heating to prevent high-temperature water from directly entering the battery. In the spring and autumn season weak heating and dehumidifying working condition, the existing thermal management system lacks a regulating mechanism capable of simultaneously accurately controlling the internal refrigerant state of the water-cooled condenser (especially the outlet superheat degree) and effectively improving the heat exchange efficiency (especially increasing the subcooling degree). This leads to problems such as excessive heating capacity of the water-cooled condenser, high outlet superheat degree, insufficient internal heat exchange, inability to effectively utilize sensible heat, inaccurate overall capacity control, and low energy efficiency, making it difficult to meet the comfortable and efficient outlet air temperature (20-35℃) control requirements. SUMMARY

[0003] In view of the above technical problems, the present application provides an indirect heat pump thermal management system for a new energy vehicle.

[0004] To achieve the above-mentioned purpose, the present application provides the following technical scheme: The present application provides an indirect heat pump thermal management system for a new energy vehicle, comprising an air conditioning refrigeration and heating system, an electric drive cooling circuit system, and a battery circuit temperature control system. The air conditioning refrigeration and heating system comprises a refrigerant circuit and a heating and cooling liquid circuit, and the refrigerant circuit and the heating and cooling liquid circuit are coupled and heat-exchanged through a water-cooled condenser. The electric drive cooling circuit system comprises an electric drive cooling liquid circuit, and the battery circuit temperature control system comprises a battery cooling liquid circuit. The electric drive cooling liquid circuit and the battery cooling liquid circuit are integratedly connected through a five-way valve, the battery cooling liquid circuit and the heating and cooling liquid circuit are integratedly connected through a proportional three-way valve, and the battery cooling liquid circuit and the refrigerant circuit are coupled and heat-exchanged through a battery cooler.

[0005] Preferably, the refrigerant circuit comprises an electric compressor, and the outlet end of the electric compressor is sequentially connected with a water-cooled condenser, a large-diameter electronic expansion valve two, a large-diameter electronic expansion valve one, an outdoor heat exchanger, a stop valve two, a one-way valve, and a gas-liquid separator. The refrigerant circuit further comprises a stop valve one and a battery cooler, one end of the stop valve one is connected between the outlet end of the electric compressor and the inlet end of the water-cooled condenser, and the other end of the stop valve one is connected between the stop valve two and the outdoor heat exchanger. The battery cooler is connected between the one-way valve and the gas-liquid separator, and the other end is sequentially connected with the battery-side electronic expansion valve, the air-conditioning-side electronic expansion valve and the evaporator, and the other end of the evaporator is connected to the inlet end of the one-way valve. The outlet end pipeline of the battery-side electronic expansion valve is connected with the outlet end pipeline of the large-diameter electronic expansion valve, and a high-pressure pressure-temperature integrated sensor is arranged at the confluence.

[0006] As preferred, the outlet end of the electric compressor is connected with a compressor exhaust temperature sensor, the inlet end is connected with a low-pressure pressure-temperature integrated sensor, the battery cooler outlet end is provided with a battery cooler outlet temperature sensor, the evaporator is provided with an evaporator surface temperature sensor, the evaporator outlet is provided with an evaporator outlet temperature sensor, and one side of the outdoor heat exchanger is provided with an electronic fan.

[0007] As preferred, the heating and cooling liquid circuit sequentially comprises a heating water pump, a water-cooled condenser liquid side, a water heater, a proportional three-way valve and a heating core according to the flow direction of the liquid.

[0008] As preferred, the electric drive cooling liquid circuit sequentially comprises an electric drive water pump, an electric drive assembly, a low-temperature radiator and a five-way valve according to the flow direction of the liquid. The inlet end of the electric drive water pump, the outlet end of the electric drive assembly and the outlet end of the low-temperature radiator are respectively connected with one port of the five-way valve. The inlet end of the electric drive assembly is provided with an electric drive inlet water temperature sensor.

[0009] As preferred, the battery cooling liquid circuit sequentially comprises a battery water pump, a battery cooler, a five-way valve and a power battery according to the flow direction of the liquid. The liquid-side outlet end of the battery cooler and the inlet end of the power battery are respectively connected with one port of the five-way valve. The inlet end of the battery water pump is provided with a shunt and connected to one port of the proportional three-way valve, and the outlet end pipeline of the heating core is connected with the outlet end pipeline of the power battery. The two ends of the power battery are respectively provided with a battery inlet water temperature sensor and a battery outlet water temperature sensor.

[0010] As preferred, the battery cooling liquid circuit sequentially comprises a battery water pump, a battery cooler, a five-way valve and a power battery according to the flow direction of the liquid. The liquid-side outlet end of the battery cooler and the inlet end of the power battery are respectively connected with one port of the five-way valve. The inlet end of the battery water pump is provided with a shunt and connected to one port of the proportional three-way valve, and the outlet end pipeline of the heating core is connected with the outlet end pipeline of the power battery. The two ends of the power battery are respectively provided with a battery inlet water temperature sensor and a battery outlet water temperature sensor.

[0011] The present invention also provides an air conditioning and heating method applicable to the above-mentioned indirect heat pump thermal management system for new energy vehicles. The air conditioning and heating system is used to realize at least one of the following modes: passenger compartment cooling, air source heat pump heating, water source heat pump heating, passenger compartment PTC heating, passenger compartment electric drive waste heat heating, and passenger compartment heating and dehumidification.

[0012] a) Passenger cabin cooling mode: The electric compressor starts, and the high-temperature and high-pressure superheated gas passes through the compressor exhaust temperature sensor and shut-off valve one (open) to reach the outdoor heat exchanger. At this time, shut-off valve two and large-diameter electronic expansion valve two are closed. The refrigerant releases heat to the environment through the electric fan and then condenses and liquefies, becoming a subcooled liquid at the outlet. It then passes through large-diameter electronic expansion valve one, which is now fully open. After passing through the high-pressure and temperature sensor, it reaches the air conditioning side electronic expansion valve. At this time, the battery side electronic expansion valve is fully closed. After being throttled and depressurized by the electronic expansion valve, it enters the evaporator for evaporation and heat absorption. Then, the blower sends cold air into the passenger cabin. The refrigerant returns to the electric compressor through the evaporator outlet temperature sensor, one-way valve, gas-liquid separator, and low-pressure sensor, completing the cycle and achieving passenger cabin cooling.

[0013] b) Air Source Heat Pump Heating Mode: The electric compressor starts, and the high-temperature, high-pressure superheated gas reaches the water-cooled condenser through the compressor exhaust temperature sensor. The refrigerant condenses and liquefies, becoming a subcooled liquid at the outlet, while simultaneously releasing heat into the heating circuit. After passing through the large-diameter electronic expansion valve two (fully open) and the high-pressure integrated pressure and temperature sensor, it is then throttled and depressurized by the large-diameter electronic expansion valve one. At this time, the air conditioning-side electronic expansion valve, the battery-side electronic expansion valve, and the shut-off valve one are all closed. The low-temperature, low-pressure, wet-saturated refrigerant enters the outdoor heat exchanger (which acts as an evaporator at this time) and absorbs heat from the environment through the electric fan. It then returns to the electric compressor through the shut-off valve two (open), the one-way valve, the gas-liquid separator, and the low-pressure sensor, completing the cycle. At the same time, the liquid-side warm air pump starts, passing sequentially through the water-cooled condenser, the water heater, the proportional three-way valve (A to C), and the warm air core, finally returning to the warm air pump to form a liquid-side loop circulation. The blower then delivers hot air into the passenger compartment to complete the passenger compartment heating.

[0014] c) Water Source Heat Pump Heating Mode (Recovering Electric Drive and Battery Waste Heat): This mode can be divided into two types: heat pump heating with recovered electric drive waste heat and heat pump heating with recovered battery waste heat. 1. Recovering Electric Drive Waste Heat: When the electric compressor starts, the high-temperature and high-pressure superheated gas reaches the water-cooled condenser through the compressor exhaust temperature sensor. The refrigerant condenses and liquefies, becoming a subcooled liquid at the outlet, while simultaneously releasing heat into the heating circuit. At this time, the large-diameter electronic expansion valve 2 is fully open. After passing through the high-pressure and temperature integrated sensor, it reaches the battery-side expansion valve for throttling and pressure reduction before entering the battery cooler. The battery cooler absorbs the electric drive waste heat. At this time, the large-diameter electronic expansion valve 1, the shut-off valve 1, and the air conditioning-side electronic expansion valve are all closed. After passing through the battery cooler outlet temperature sensor, the gas-liquid separator, and the low-pressure sensor, it returns to the electric compressor, completing the refrigerant cycle. Simultaneously, the liquid-side heater pump starts, circulating hot air sequentially through the water-cooled condenser, water heater, proportional three-way valve (A in, C out), and heater core, ultimately returning to the heater pump to form a liquid-side loop. The blower then delivers hot air into the passenger compartment to complete the heating. At this time, the electric drive water pump starts, absorbing heat from the coolant entering the electric drive assembly via the electric drive inlet water temperature sensor. The coolant then passes through a five-way valve (1 in, 3 out, B in, 2 out) to the power battery, passes through the battery water pump, enters the battery cooler to absorb waste heat, and then returns to the electric drive water pump through the five-way valve to complete the loop. Battery waste heat recovery: The refrigerant loop connection is the same as for electric drive waste heat recovery. At this time, the liquid-side five-way valve (1 in, 2 out, B in, 3 out) is activated, the battery water pump starts, the coolant absorbs waste heat, and the coolant passes through the five-way valve to the power battery to absorb heat before returning to the battery water pump to complete the loop.

[0015] d) Passenger Cabin PTC Heating Mode: This mode can be used in extremely cold conditions. In this mode, the heater pump, water heater, heater core, and proportional three-way valve (a inlet, c outlet) complete the water circulation. The water heater needs to provide feedback on the outlet water temperature; if it does not, an additional water temperature sensor is required. The water heater adjusts its output power based on the water temperature sensor to ensure the comfort of the passenger cabin heating.

[0016] e) Passenger Cabin Heating and Dehumidification Mode: This mode can be divided into series dehumidification and parallel dehumidification. Series dehumidification (outlet air temperature 20~35℃ in spring and autumn): The electric compressor starts, and a portion of the high-pressure, high-temperature refrigerant enters the water-cooled condenser after passing through the compressor exhaust temperature sensor. The refrigerant condenses and liquefies, becoming a subcooled liquid at the outlet, while simultaneously releasing heat into the heating circuit. After passing through the large-diameter electronic expansion valve II (which can regulate the refrigerant flow in the water-cooled condenser), a portion enters the outdoor heat exchanger (which acts as the condenser) through the shut-off valve I. After passing through the large-diameter electronic expansion valve I, it merges with another portion of the refrigerant at the high-pressure pressure and temperature sensor. Then, it passes through the air conditioning side electronic expansion valve for throttling and pressure reduction before entering the evaporator. The blower dehumidifies the air after passing through the evaporator, and after being heated by the heating core, it is blown into the passenger cabin to achieve heating and dehumidification. At this time, the heater pump starts, and the coolant enters the water-cooled condenser to absorb heat. After passing through the water heater, it passes through the proportional three-way valve (A in, C out) into the heater core and then returns to the heater pump. Parallel dehumidification: When the electric compressor starts, a portion of the high-pressure, high-temperature refrigerant passes through the compressor discharge temperature sensor and enters the water-cooled condenser. The refrigerant condenses and liquefies, becoming a subcooled liquid at the outlet, while simultaneously releasing heat to the heating circuit. After passing through the large-diameter electronic expansion valve two (fully open), it is split after passing through the high-pressure integrated pressure and temperature sensor. A portion passes through the air conditioning side electronic expansion valve (controlling the evaporator surface temperature) for throttling and pressure reduction before entering the evaporator. Another portion passes through the large-diameter electronic expansion valve one for throttling and pressure reduction before absorbing heat in the outdoor heat exchanger (acting as the evaporator). After passing through the shut-off valve two, the refrigerant merges and enters the check valve. After passing through the liquid separator and low-pressure sensor, it returns to the electric compressor to complete the refrigerant circuit cycle. The liquid-side circuit is the same as in series dehumidification.

[0017] The present invention also provides a battery temperature control method applicable to the above-mentioned indirect heat pump thermal management system for new energy vehicles, wherein the battery circuit temperature control system is used to realize at least one of the following modes: forced cooling of the battery, natural heat dissipation of the battery, PTC heating of the battery, and electric drive waste heat heating of the battery.

[0018] a) Forced Battery Cooling Mode: In this mode, the battery circuit and the electric drive circuit are connected in parallel and do not interfere with each other. In the refrigerant circuit, the high-temperature, high-pressure superheated gas exits from the electric compressor, passes through the compressor exhaust temperature sensor and shut-off valve one, and reaches the outdoor heat exchanger (which acts as a condenser at this time). The refrigerant condenses and liquefies, becoming a subcooled liquid at the outlet. The heat is released to the environment through the electric fan. After passing through the large-diameter electronic expansion valve one (fully open) and the high-pressure and temperature integrated sensor, it reaches the battery-side electronic expansion valve. At this time, shut-off valve two is closed, and the air conditioning-side electronic expansion valve and the large-diameter electronic expansion valve two are fully closed. After being throttled and depressurized by the electronic expansion valve, it enters the battery cooler to evaporate and absorb heat. The refrigerant returns to the electric compressor through the battery cooler outlet temperature sensor, gas-liquid separator, and low-pressure sensor, completing the refrigeration cycle. At this time, the battery water pump in the liquid-side battery circuit starts, enters the battery cooler to release heat, passes through the five-way valve (1 inlet, 2 outlet), passes through the battery inlet water temperature sensor, enters the power battery to absorb heat, and then returns to the battery water pump through the battery outlet water temperature sensor, forming a liquid-side circulation and completing the battery pack cooling.

[0019] b) Battery Natural Cooling Mode: In this mode, the battery circuit and electric drive circuit are connected in series, the refrigerant circuit is not working, and cooling is achieved through a low-temperature radiator. In this mode, the electric fan, battery water pump, battery inlet water temperature sensor, power battery, battery outlet water temperature sensor, five-way valve (coolant inlet from 1, outlet from 3; inlet from A, outlet from 2), electric drive water pump, electric drive assembly, and electric drive inlet water temperature sensor need to operate. Based on feedback from the motor and battery water temperature sensors, the system precisely controls the water pump flow rate and the position and opening of the five-way valve for natural battery cooling. This mode saves energy when battery cooling demand is low.

[0020] e) Battery PTC Heating Mode: In this mode, the heating circuit and battery circuit operate simultaneously, the refrigerant circuit is not operating, and the water heater operates, utilizing the heating capacity of the water heater to meet the maximum heating requirements of the battery under ultra-low temperatures. In this mode, the heating water pump and battery water pump start simultaneously. The water heater in the heating circuit passes through a proportional three-way valve (a inlet, b outlet), the battery water pump, a five-way valve (1 inlet, 2 outlet), and the battery inlet water temperature sensor to the power battery to heat the battery. The water heater adjusts its output power based on feedback from the battery inlet water temperature sensor to ensure a certain battery inlet water temperature. The battery water pump adjusts its duty cycle according to the target water flow rate for battery heating to ensure the water flow rate for battery heating.

[0021] f) Battery Heating Mode with Waste Heat from Electric Drive: In this mode, the battery circuit and the electric drive circuit are connected in series to recover waste heat from the electric drive circuit to keep the power battery warm. In this mode, the battery water pump and the electric drive water pump start simultaneously. The battery water pump sends coolant through the battery cooler and a five-way valve (1 inlet, 3 outlets; B inlet, 2 outlets), then into the electric drive water pump. After passing through the electric drive inlet water temperature sensor, it enters the electric drive assembly, absorbs heat, passes through the five-way valve and the electric drive inlet water temperature sensor again, and then enters the power battery. After heating the power battery, it passes through the battery outlet water temperature sensor and returns to the battery water pump to complete the cycle. Based on the feedback from the water temperature sensor, the water pump flow rate is precisely controlled to recover waste heat from the motor into the battery.

[0022] The present invention also provides an electric drive cooling method applicable to the above-mentioned indirect heat pump thermal management system for new energy vehicles, wherein the electric drive cooling circuit system is used to realize the cooling mode of the electric drive assembly.

[0023] In the electric drive assembly cooling mode, the electric fan, electric drive water pump, electric drive inlet water temperature sensor, low-temperature radiator, and five-way valve (in this mode, coolant enters through port A and exits through port 3) need to operate. The system cools the motor through the low-temperature radiator.

[0024] Compared with the prior art, the present invention provides an indirect heat pump thermal management system for new energy vehicles, which has the following beneficial effects: This invention integrates a five-way valve and a proportional three-way valve into a water circuit, combining the battery outlet water and the heating core outlet water before splitting them. The proportional three-way valve distributes the flow rate, mixes the combined water with the mixed water, and then enters the battery to control the battery's inlet water temperature. This saves one water-to-water heat exchanger, achieving cost reduction and efficiency improvement. On the agent side, a large-diameter electronic expansion valve is installed at the outlet of the water-cooled condenser. By adjusting its opening, the internal flow and state of the water-cooled condenser can be actively controlled, which can improve subcooling, suppress superheating, enhance heat exchange, and provide precise control capabilities, thus better achieving temperature control of the heating and dehumidification outlet air in spring and autumn.

[0025] The features and advantages of the present invention will be described in detail through embodiments and in conjunction with the accompanying drawings. Attached Figure Description

[0026] Figure 1 This is a schematic diagram of an indirect heat pump thermal management system for new energy vehicles according to the present invention. Detailed Implementation

[0027] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. However, it should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of the invention. Furthermore, descriptions of well-known structures and technologies are omitted in the following description to avoid unnecessarily obscuring the concept of the invention.

[0028] See Figure 1 An indirect heat pump thermal management system for new energy vehicles includes an air conditioning cooling and heating system, an electric drive cooling circuit system, and a battery circuit temperature control system. The air conditioning and heating system includes a refrigerant circuit and a heating coolant circuit, which are coupled and exchange heat through a water-cooled condenser 16. The electric drive cooling circuit system includes an electric drive coolant circuit, and the battery circuit temperature control system includes a battery coolant circuit. The electric drive coolant circuit and the battery coolant circuit are integrated and connected through a five-way valve 22. The battery coolant circuit and the heating coolant circuit are integrated and connected through a proportional three-way valve 27. The battery coolant circuit and the refrigerant circuit are coupled and exchange heat through a battery cooler 14.

[0029] Preferably, the refrigerant circuit includes an electric compressor 1, and the outlet end of the electric compressor 1 is sequentially connected to a water-cooled condenser 16, a large-diameter electronic expansion valve 2 17, a large-diameter electronic expansion valve 1 7, an outdoor heat exchanger 5, a shut-off valve 2 4, a one-way valve 18, and a gas-liquid separator 19. The refrigerant circuit also includes a shut-off valve 3 and a battery cooler 14. One end of the shut-off valve 3 is connected between the outlet end of the electric compressor 1 and the refrigerant side inlet end of the water-cooled condenser 16, and the other end of the shut-off valve 3 is connected between a shut-off valve 4 and the outdoor heat exchanger 5. The battery cooler 14 is connected at one end between the one-way valve 18 and the gas-liquid separator 19, and at the other end is connected in sequence to the battery-side electronic expansion valve 13, the air-conditioning-side electronic expansion valve 9 and the evaporator 10. The other end of the evaporator 10 is connected to the inlet end of the one-way valve 18. The outlet pipe of the battery-side electronic expansion valve 13 is connected to the outlet pipe of the large-diameter electronic expansion valve 17, and a high-pressure and temperature integrated sensor 8 is provided at the junction.

[0030] Preferably, the outlet end of the electric compressor 1 is connected to a compressor exhaust temperature sensor 2, and the inlet end is connected to a low-pressure temperature integrated sensor 20. The battery cooler 14 is provided with a battery cooler outlet temperature sensor 15 at the agent side outlet end. The evaporator 10 is provided with an evaporator surface temperature sensor 11, and the evaporator 10 outlet is provided with an evaporator outlet temperature sensor 12. An electric fan 6 is provided on one side of the outdoor heat exchanger 5.

[0031] Preferably, the heating coolant circuit includes, in sequence according to the coolant flow direction, a heater pump 25, a water-cooled condenser 16 (liquid side), a water heater 26, a proportional three-way valve 27, and a heater core 28.

[0032] Preferably, the electric drive coolant circuit includes, in sequence according to the coolant flow direction, an electric drive water pump 30, an electric drive assembly 32, a low-temperature radiator 33, and a five-way valve 22; The inlet end of the electric water pump 30, the outlet end of the electric drive assembly 32, and the outlet end of the low-temperature radiator 33 are respectively connected to one port of the five-way valve 22. The electric drive assembly 32 is equipped with an electric drive inlet water temperature sensor 31.

[0033] Preferably, the battery coolant circuit includes, in sequence according to the coolant flow direction, a battery water pump 21, a battery cooler 14, a five-way valve 22, and a power battery 23; The liquid-side outlet of the battery cooler 14 and the inlet of the power battery 23 are respectively connected to one port of the five-way valve 22. The inlet end of the battery water pump 21 is provided with a branch and connected to one port of the proportional three-way valve 27, and the outlet end pipe of the heater core 28 is connected to the outlet end pipe of the power battery 23. The power battery 23 is equipped with a battery inlet water temperature sensor 29 and a battery outlet water temperature sensor 24 at its two ends, respectively.

[0034] The present invention also provides an air conditioning and heating method applicable to the above-mentioned indirect heat pump thermal management system for new energy vehicles. The air conditioning and heating system is used to realize at least one of the following modes: passenger compartment cooling, air source heat pump heating, water source heat pump heating, passenger compartment PTC heating, passenger compartment electric drive waste heat heating, and passenger compartment heating and dehumidification.

[0035] a) Passenger cabin cooling mode: Electric compressor 1 starts, shut-off valve 3 opens, and high-temperature, high-pressure superheated gas reaches outdoor heat exchanger 5 via compressor exhaust temperature sensor 2 and shut-off valve 3. At this time, shut-off valve 4 and large-diameter electronic expansion valve 17 are closed. The refrigerant releases heat to the environment through electric fan 6 and condenses into a subcooled liquid at the outlet. It then passes through large-diameter electronic expansion valve 7, which is now fully open. After passing through high-pressure integrated pressure and temperature sensor 8, it reaches air conditioning side electronic expansion valve 9. At this time, battery side electronic expansion valve 13 is fully closed. After being throttled and depressurized by the electronic expansion valve, it enters evaporator 10 for evaporation and heat absorption. Then, the cold air is sent into the passenger cabin by the blower. The refrigerant returns to electric compressor 1 via evaporator outlet temperature sensor 12, one-way valve 18, gas-liquid separator 19, and low-pressure integrated pressure and temperature sensor 20, completing the cycle and achieving passenger cabin cooling.

[0036] b) Air source heat pump heating mode: Electric compressor 1 starts, high temperature and high pressure superheated gas reaches water-cooled condenser 16 through compressor exhaust temperature sensor 2, refrigerant condenses and liquefies, becomes subcooled liquid at the outlet, and releases heat to the heating circuit at the same time. Large-diameter electronic expansion valve 17 is fully open, passes through large-diameter electronic expansion valve 17 and high pressure integrated pressure and temperature sensor 8, and then is throttled and depressurized by large-diameter electronic expansion valve 7. At this time, air conditioner side electronic expansion valve 9, battery side electronic expansion valve 13 and shut-off valve 3 are fully closed. Low temperature and low pressure wet saturated refrigerant enters outdoor heat exchanger 5 (at this time, outdoor heat exchanger 5 is used as an evaporator), and absorbs heat from the environment through electric fan 6. Shut-off valve 4 is opened, passes through shut-off valve 4, one-way valve 18, gas-liquid separator 19 and low pressure integrated pressure and temperature sensor 20 and returns to electric compressor 1 to complete the cycle. At the same time, the liquid-side heating water pump 25 starts, and the water flows through the water-cooled condenser 16, water heater 26, proportional three-way valve 27a to c, and heating core 28 in sequence, and finally returns to the heating water pump 25 to form a liquid-side loop circulation. The hot air is then sent into the crew compartment by the blower to complete the heating of the crew compartment.

[0037] c) Water source heat pump heating mode (recovery of electric drive and battery waste heat): This mode can be divided into two types: heat pump heating with recovery of electric drive waste heat and heat pump heating with recovery of battery waste heat. 1. Recovery of electric drive waste heat: When the electric compressor 1 starts, the high-temperature and high-pressure superheated gas reaches the water-cooled condenser 16 through the compressor exhaust temperature sensor 2. The refrigerant condenses and liquefies, becoming a subcooled liquid at the outlet, and at the same time releases heat to the heating circuit. At this time, the large-diameter electronic expansion valve 17 is fully open. After passing through the high-pressure integrated pressure and temperature sensor 8, it reaches the battery-side electronic expansion valve 13 for throttling and pressure reduction, and then enters the battery cooler 14. The battery cooler 14 absorbs the electric drive waste heat. At this time, the large-diameter electronic expansion valve 7, the shut-off valve 3, and the air conditioning-side electronic expansion valve 9 are all closed. After passing through the battery cooler outlet temperature sensor 15, the gas-liquid separator 19, and the low-pressure integrated pressure and temperature sensor 20, it returns to the electric compressor 1, completing the refrigerant cycle. Simultaneously, the liquid-side heater pump 25 starts, sequentially passing through the water-cooled condenser 16, water heater 26, proportional three-way valve 27a (inlet) and c (outlet), and heater core 28, finally returning to the heater pump 25 to form a liquid-side loop circulation. Hot air is then delivered into the passenger compartment via a blower to complete passenger compartment heating. At this time, the electric drive water pump 30 starts, passing through the electric drive inlet water temperature sensor 31, entering the electric drive assembly 32 coolant to absorb heat, then passing through the five-way valve 22 (1 inlet, 3 outlet, B inlet, 2 outlet) to enter the power battery 23, passing through the battery water pump 21, entering the battery cooler 14 to absorb waste heat, and then returning to the electric drive water pump 30 through the five-way valve to complete the circulation. Battery waste heat recovery: The refrigerant loop connection is the same as for recovering electric drive waste heat. At this time, the liquid-side five-way valve 22 (1 inlet, 2 outlet, B inlet, 3 outlet), the battery water pump starts, passes through the battery cooler 14 to absorb waste heat, passes through the five-way valve 22 to enter the power battery to absorb heat, and then returns to the battery water pump 21 to complete the circulation.

[0038] d) Passenger Cabin PTC Heating Mode: This mode can be used in extremely cold conditions. In this mode, the heater pump 25, water heater 26, heater core 28, and proportional three-way valve 27a (inlet) and c (outlet) complete the water circulation. The water heater 26 needs to provide feedback on the outlet water temperature; if it does not, an additional water temperature sensor is required. The water heater adjusts its output power based on the water temperature sensor to ensure comfortable heating in the passenger cabin.

[0039] e) Passenger cabin heating and dehumidification mode: This mode can be divided into series dehumidification and parallel dehumidification. Series dehumidification (outlet air temperature 20~35℃ in spring and autumn): Electric compressor 1 starts, high-pressure and high-temperature refrigerant passes through compressor exhaust temperature sensor 2, part of which enters water-cooled condenser 16. The refrigerant condenses and liquefies, becoming a subcooled liquid at the outlet, while releasing heat to the heating circuit. After passing through large-diameter electronic expansion valve 17 (which can regulate the refrigerant flow of the water-cooled condenser), part of it enters outdoor heat exchanger 4 through shut-off valve 3. After passing through the condenser, it passes through large-diameter electronic expansion valve 7 and merges with another part of the refrigerant at high pressure and temperature sensor 8. After passing through air conditioning side electronic expansion valve 9 for throttling and pressure reduction, it enters evaporator 10. The blower dehumidifies the air after passing through the evaporator, and after being heated by the heating core, it is blown into the passenger cabin to achieve heating and dehumidification. At this time, the heater pump 25 starts, and the coolant enters the water-cooled condenser 16 to absorb heat. After passing through the water heater 26, it enters the heater core 28 through the proportional three-way valve 27a and exits through the c-way valve, and then returns to the heater pump 25. Parallel dehumidification: When the electric compressor 1 starts, a portion of the high-pressure, high-temperature refrigerant passes through the compressor discharge temperature sensor 2 and enters the water-cooled condenser 16. The refrigerant condenses and liquefies, becoming a subcooled liquid at the outlet, while simultaneously releasing heat to the heating circuit. The large-diameter electronic expansion valve 17 is fully open. After passing through the large-diameter electronic expansion valve 17 and the high-pressure integrated pressure and temperature sensor 8, the refrigerant is split. A portion passes through the air conditioning side electronic expansion valve 9 (which controls the evaporator surface temperature) to reduce pressure and enters the evaporator 10. Another portion passes through the large-diameter electronic expansion valve 7 to reduce pressure and enters the outdoor heat exchanger 5. When the evaporator absorbs heat, the refrigerant merges after passing through the shut-off valve 4 and enters the one-way valve 18. After passing through the gas-liquid separator 19 and the low-pressure integrated pressure and temperature sensor 20, the refrigerant returns to the electric compressor 1 to complete the refrigerant circuit cycle. The liquid-side circuit is the same as in series dehumidification.

[0040] The present invention also provides a battery temperature control method applicable to the above-mentioned indirect heat pump thermal management system for new energy vehicles, wherein the battery circuit temperature control system is used to realize at least one of the following modes: forced cooling of the battery, natural heat dissipation of the battery, PTC heating of the battery, and electric drive waste heat heating of the battery.

[0041] a) Forced Battery Cooling Mode: In this mode, the battery circuit and the electric drive circuit are connected in parallel and do not interfere with each other. In the refrigerant circuit, the high-temperature and high-pressure superheated gas exits from the electric compressor 1, passes through the compressor exhaust temperature sensor 2 and the shut-off valve 3, and reaches the outdoor heat exchanger 5 (which acts as a condenser at this time). The refrigerant condenses and liquefies, becoming a subcooled liquid at the outlet. The heat is released to the environment through the electric fan 6. The large-diameter electronic expansion valve 7 is fully open, and the gas passes through the large-diameter electronic expansion valve 7 and the high-pressure integrated pressure and temperature sensor 8 to reach the battery-side electronic expansion valve 13. At this time, the shut-off valve 4 is closed, and the air conditioning-side electronic expansion valve 9 and the large-diameter electronic expansion valve 17 are fully closed. After being throttled and depressurized by the electronic expansion valve, the gas enters the battery cooler 14 to evaporate and absorb heat. The refrigerant returns to the electric compressor 1 through the battery cooler outlet temperature sensor 15, the gas-liquid separator 19, and the low-pressure integrated pressure and temperature sensor 20, completing the refrigeration cycle. At this time, the battery water pump 21 in the liquid-side battery circuit starts, enters the battery cooler to release heat, passes through the five-way valve 22 (1 inlet, 2 outlets), passes through the battery inlet water temperature sensor 29, enters the power battery 23 to absorb heat, and then passes through the battery outlet water temperature sensor 24 to return to the battery water pump 21 to form a liquid-side circulation, thus completing the cooling of the battery pack.

[0042] b) Battery Natural Cooling Mode: In this mode, the battery circuit and electric drive circuit are connected in series, the refrigerant circuit is not working, and cooling is achieved by the low-temperature radiator 33. In this mode, the electric fan 6, battery water pump 21, battery inlet water temperature sensor 29, power battery 23, battery outlet water temperature sensor 24, coolant from the five-way valve 22 (1 inlet 3 outlet, A inlet 2 outlet), electric drive water pump 30, electric drive assembly 32, and electric drive inlet water temperature sensor 31 need to operate. Based on feedback from the motor and battery water temperature sensors, the system precisely controls the water pump flow rate and the position and opening of the five-way valve for natural battery cooling. This mode saves energy when battery cooling demand is low.

[0043] e) Battery PTC Heating Mode: In this mode, the heating circuit and battery circuit operate simultaneously, the refrigerant circuit does not operate, and the water heater 26 operates, utilizing the heating capacity of the water heater to meet the maximum heating requirements of the battery under ultra-low temperatures. In this mode, the heating water pump 25 and the battery water pump 21 start simultaneously. The water heater 26 of the heating circuit enters through the proportional three-way valve 27a and exits through the battery water pump 21, the five-way valve 22 (1 inlet, 2 outlets), and the battery inlet water temperature sensor 29 to heat the power battery 23. The water heater 26 adjusts its output power according to the feedback from the battery inlet water temperature sensor 29 to ensure a certain battery inlet water temperature. The battery water pump 21 adjusts its duty cycle according to the target water flow rate for battery heating to ensure the water flow rate for battery heating.

[0044] f) Battery Heating Mode Using Waste Heat from Electric Drive: In this mode, the battery circuit and the electric drive circuit are connected in series to recover waste heat from the electric drive circuit to keep the power battery 23 warm. In this mode, the battery water pump 21 and the electric drive water pump 30 start simultaneously. The battery water pump 21 pumps coolant through the battery cooler 14 and the five-way valve 22 (1 inlet, 3 outlets; B inlet, 2 outlets), then into the electric drive water pump 30. After passing through the electric drive inlet water temperature sensor 31, it enters the electric drive assembly 32, absorbs heat, passes through the five-way valve 22 and the electric drive inlet water temperature sensor 31, and then enters the power battery 23, heating it. After passing through the battery outlet water temperature sensor 24, it returns to the battery water pump 21 to complete the cycle. Based on the feedback from the water temperature sensor, the water pump flow rate is precisely controlled to recover waste heat from the motor into the battery.

[0045] The present invention also provides an electric drive cooling method applicable to the above-mentioned indirect heat pump thermal management system for new energy vehicles, wherein the electric drive cooling circuit system is used to realize the cooling mode of the electric drive assembly.

[0046] In the electric drive assembly cooling mode, the electric fan 6, electric drive water pump 30, electric drive inlet water temperature sensor 31, low-temperature radiator 33, and five-way valve 22 (in this mode, coolant enters through port A and exits through port 3) need to operate. The system cools the motor through the low-temperature radiator.

[0047] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions or improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. An indirect heat pump thermal management system for new energy vehicles, characterized in that: This includes air conditioning and heating systems, electric drive cooling circuit systems, and battery circuit temperature control systems; The air conditioning and heating system includes a refrigerant circuit and a heating coolant circuit, which are coupled and exchange heat through a water-cooled condenser (16). The electric drive cooling circuit system includes an electric drive coolant circuit, and the battery circuit temperature control system includes a battery coolant circuit. The electric drive coolant circuit and the battery coolant circuit are integrated and connected through a five-way valve (22), the battery coolant circuit and the heating coolant circuit are integrated and connected through a proportional three-way valve (27), and the battery coolant circuit and the refrigerant circuit are coupled and exchange heat through a battery cooler (14).

2. The indirect heat pump thermal management system for new energy vehicles as described in claim 1, characterized in that: The refrigerant circuit includes an electric compressor (1), and the outlet end of the electric compressor (1) is sequentially connected to a water-cooled condenser (16), a large-diameter electronic expansion valve II (17), a large-diameter electronic expansion valve I (7), an outdoor heat exchanger (5), a shut-off valve II (4), a check valve (18), and a gas-liquid separator (19). The refrigerant circuit also includes a shut-off valve (3) and a battery cooler (14). One end of the shut-off valve (3) is connected between the outlet end of the electric compressor (1) and the refrigerant side inlet end of the water-cooled condenser (16). The other end of the shut-off valve (3) is connected between the shut-off valve (4) and the outdoor heat exchanger (5). One end of the battery cooler (14) is connected between the one-way valve (18) and the gas-liquid separator (19), and the other end is connected in sequence to the battery-side electronic expansion valve (13), the air-conditioning-side electronic expansion valve (9) and the evaporator (10). The other end of the evaporator (10) is connected to the inlet end of the one-way valve (18). The outlet pipe of the battery-side electronic expansion valve (13) is connected to the outlet pipe of the large-diameter electronic expansion valve II (17), and a high-pressure and temperature integrated sensor (8) is provided at the junction.

3. The indirect heat pump thermal management system for new energy vehicles as described in claim 2, characterized in that: The electric compressor (1) is connected to a compressor exhaust temperature sensor (2) at the outlet end and a low-pressure temperature sensor (20) at the inlet end. The battery cooler (14) is provided with a battery cooler outlet temperature sensor (15) at the outlet end on the agent side. The evaporator (10) is provided with an evaporator surface temperature sensor (11) and an evaporator outlet temperature sensor (12) at the outlet of the evaporator (10). An electric fan (6) is provided on one side of the outdoor heat exchanger (5).

4. The indirect heat pump thermal management system for new energy vehicles as described in claim 1, characterized in that: The heating cooling fluid circuit includes, in sequence according to the flow direction of the cooling fluid, a hot air pump (25), a water-cooled condenser (16) liquid side, a water heater (26), a proportional three-way valve (27), and a hot air core (28).

5. The indirect heat pump thermal management system for new energy vehicles as described in claim 1, characterized in that: The electric drive coolant circuit includes, in sequence according to the coolant flow direction, an electric drive water pump (30), an electric drive assembly (32), a low-temperature radiator (33), and a five-way valve (22). The inlet end of the electric water pump (30), the outlet end of the electric drive assembly (32) and the outlet end of the low temperature radiator (33) are respectively connected to one port of the five-way valve (22); The electric drive assembly (32) is equipped with an electric drive inlet water temperature sensor (31).

6. The indirect heat pump thermal management system for new energy vehicles as described in claim 4, characterized in that: The battery coolant circuit includes, in sequence according to the coolant flow direction, a battery water pump (21), a battery cooler (14), a five-way valve (22), and a power battery (23). The liquid-side outlet of the battery cooler (14) and the inlet of the power battery (23) are respectively connected to one port of the five-way valve (22); The battery water pump (21) has a branch at its inlet end and is connected to one port of the proportional three-way valve (27). The outlet pipe of the warm air core (28) is connected to the outlet pipe of the power battery (23). The power battery (23) is equipped with a battery inlet water temperature sensor (29) and a battery outlet water temperature sensor (24) at both ends.

7. An air conditioning and heating method for an indirect heat pump thermal management system for new energy vehicles as described in any one of claims 1 to 6, characterized in that: The air conditioning and heating system is used to realize at least one of the following modes: passenger cabin cooling, air source heat pump heating, water source heat pump heating, passenger cabin PTC heating, passenger cabin electric waste heat heating, and passenger cabin heating and dehumidification.

8. A battery temperature control method for an indirect heat pump thermal management system for new energy vehicles as described in any one of claims 1 to 6, characterized in that: The battery circuit temperature control system is used to realize at least one of the following modes: forced cooling of the battery, natural heat dissipation of the battery, PTC heating of the battery, and electric drive waste heat heating of the battery.

9. An electric drive cooling method for an indirect heat pump thermal management system for new energy vehicles as described in any one of claims 1 to 6, characterized in that: The electric drive cooling circuit system is used to realize the cooling mode of the electric drive assembly.

Images