Integrated thermal management system for new energy pure electric vehicle

Abstract

The invention relates to the technical field of new energy vehicle thermal management, and belongs to a new energy pure electric vehicle integrated thermal management system which comprises a refrigerant loop and a cooling liquid loop, and the refrigerant loop and the cooling liquid loop are coupled for heat exchange through a heat exchange assembly; the cooling liquid loop comprises a heating cooling liquid loop, a battery cooling liquid loop and an electric drive cooling liquid loop, the battery cooling liquid loop and the electric drive cooling liquid loop are integrally connected through a five-way valve, and the heating cooling liquid loop and the battery cooling liquid loop are connected through a three-way valve. An air source heat pump is omitted, a system for connecting an electric drive, a battery and heating through a five-way valve and a three-way valve is formed, a water source heat pump of the system can absorb heat of the electric drive and the battery, meanwhile, a WPTC of a battery loop and an electronic expansion valve of an outdoor heat exchanger are omitted, most parts are integrated, the cost is effectively reduced, and the system is suitable for popularization and application. And more reasonable energy distribution of the cooling liquid is realized.

Description

Technical Field

[0001] This invention relates to the field of thermal management technology for new energy vehicles, and specifically to an integrated thermal management system for new energy pure electric vehicles. Background Technology

[0002] In recent years, with the development of high technology, extending the driving range of new energy vehicles has become an inevitable trend in current testing needs. In the commercial vehicle sector, battery energy density has been increasing year by year. For new energy vehicles, winter air conditioning heating and battery heating are the main operating conditions that reduce driving range. Therefore, the importance of heat pump systems for new energy commercial vehicles is self-evident.

[0003] In common engineering applications, the operating temperature range of air source heat pumps is greatly affected by the ambient temperature. Typically, water / air heaters need to be installed on the heating or battery side to meet the heating needs when the ambient temperature cannot meet the operating temperature requirements of the air source heat pump. At the same time, additional electronic expansion valves need to be installed at the system control level to control the supercooling / superheating, which also increases the cost of current highly integrated heat pump systems. Summary of the Invention

[0004] To address the aforementioned technical problems, this invention provides an integrated thermal management system for new energy pure electric vehicles.

[0005] To achieve the above objectives, the present invention provides the following technical solution: This invention provides an integrated thermal management system for new energy pure electric vehicles, including a refrigerant circuit and a coolant circuit, wherein the refrigerant circuit and the coolant circuit are coupled and exchange heat through a heat exchange component; The coolant circuit includes a heating coolant circuit, a battery coolant circuit, and an electric drive coolant circuit. The battery coolant circuit and the electric drive coolant circuit are integrated and connected through a five-way valve, and the heating coolant circuit and the battery coolant circuit are connected through a three-way valve.

[0006] Preferably, the refrigerant circuit includes, in sequence according to the refrigerant flow direction, a compressor, a water-cooled condenser (LCC) refrigerant side, an outdoor heat exchanger (OHX), an evaporator (Evap), and a gas-liquid separator, with the battery-plate heat exchanger (Chiller) refrigerant side connected in parallel to both ends of the evaporator (Evap). A shut-off valve is connected in series between the outlet end of the LCC refrigerant side of the water-cooled condenser and the inlet end of the OHX outdoor heat exchanger. A check valve is connected to the outlet end of the OHX outdoor heat exchanger. The inlet end of a shut-off valve is connected between the outlet end of the LCC refrigerant side of the water-cooled condenser and the shut-off valve. The outlet end of the shut-off valve is connected to the outlet end of the check valve. An expansion valve is connected in series between the outlet end of the outdoor heat exchanger OHX and the inlet end of the evaporator Evap. An expansion valve is connected between the outlet end of the outdoor heat exchanger OHX and the expansion valve, and the outlet end of the expansion valve is connected to the inlet end of the water-cooled condenser LCC refrigerant side.

[0007] Preferably, a condenser fan is provided on one side of the evaporator.

[0008] Preferably, the heating coolant circuit includes, in sequence according to the coolant flow direction, a heater pump HeatEWP, a water-cooled condenser LCC liquid side, a heater WPTC, a three-way valve, and a heater core. The inlet end of the heater core and the outlet end of the heater WPTC are respectively connected to one port of the three-way valve.

[0009] Preferably, the battery coolant circuit includes, in sequence according to the coolant flow direction, a battery water pump, a power battery, a battery plate heat exchanger (Chiller liquid side), and a five-way valve. The inlet end of the battery water pump and the liquid-side outlet end of the battery plate heat exchanger Chiller are respectively connected to port 1 of the five-way valve. A two-way shut-off valve is provided between the battery water pump and the five-way valve. A branch is provided between the battery water pump and the two-way shut-off valve and connected to the warm air water pump and the liquid side of the water-cooled condenser LCC. A one-way valve is provided on this branch. A branch is provided between the two-way shut-off valve and the battery water pump and connected to port 1 of the three-way valve.

[0010] Preferably, the electric drive coolant circuit includes, in sequence according to the coolant flow direction, an electric drive water pump MotEXP, an electric drive assembly, a low-temperature radiator LTR, and a five-way valve. The inlet end of the electric drive water pump MotEXP and the outlet end of the low-temperature radiator LTR are respectively connected to one port of the five-way valve. A branch is provided between the outlet end of the electric drive assembly and the inlet end of the low-temperature radiator LTR and connected to one port of the five-way valve.

[0011] Preferably, the low-temperature heat sink (LTR) has an electronic fan on one side.

[0012] Compared with the prior art, the present invention provides an integrated thermal management system for new energy pure electric vehicles, which has the following beneficial effects: This invention eliminates the air source heat pump, forming a system that connects the electric drive, battery, and heating using a five-way valve and a three-way valve. The water source heat pump in this system can absorb the heat from the electric drive and battery. At the same time, it eliminates the WPTC in the battery circuit and the electronic expansion valve of the outdoor heat exchanger, and integrates most of the components, effectively reducing costs and achieving a more reasonable energy distribution of the coolant.

[0013] 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

[0014] Figure 1 This is a schematic diagram of an integrated thermal management system for a new energy pure electric vehicle according to the present invention. Detailed Implementation

[0015] 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.

[0016] See Figure 1 An integrated thermal management system for a new energy pure electric vehicle includes a refrigerant circuit and a coolant circuit, wherein the refrigerant circuit and the coolant circuit are coupled and exchange heat through a heat exchange component. The coolant circuit includes a heating coolant circuit, a battery coolant circuit, and an electric drive coolant circuit. The battery coolant circuit and the electric drive coolant circuit are integrated and connected through a five-way valve 17, and the heating coolant circuit and the battery coolant circuit are connected through a three-way valve 14.

[0017] Specifically, the refrigerant circuit includes, in sequence according to the refrigerant flow direction, a compressor 1, a water-cooled condenser LCC2 (refrigerant side), an outdoor heat exchanger OHX3, an evaporator Evap4, and a gas-liquid separator 6, and the battery-plate heat exchanger Chiller5 (refrigerant side) is connected in parallel to both ends of the evaporator Evap4; A shut-off valve 7 is connected in series between the refrigerant-side outlet of the water-cooled condenser LCC2 and the inlet of the outdoor heat exchanger OHX3. A one-way valve 24 is connected to the outlet of the outdoor heat exchanger OHX3. The inlet of a shut-off valve 8 is connected between the refrigerant-side outlet of the water-cooled condenser LCC2 and the shut-off valve 7. The outlet of the shut-off valve 8 is connected to the outlet of the one-way valve 24. An expansion valve 9 is connected in series between the outlet end of the outdoor heat exchanger OHX3 and the inlet end of the evaporator Evap4. An expansion valve 10 is connected between the outlet end of the outdoor heat exchanger OHX3 and the expansion valve 9. The outlet end of the expansion valve 10 is connected to the refrigerant side inlet end of the water-cooled condenser LCC2.

[0018] Specifically, a condenser fan 22 is provided on one side of the evaporator Evap4.

[0019] Specifically, the heating coolant circuit includes, in sequence according to the coolant flow direction, a heater pump HeatEWP11, a water-cooled condenser LCC2 liquid side, a heater WPTC12, a three-way valve 14, and a heater core HeatCore13. The inlet end of the heater core HeatCore13 and the outlet end of the heater WPTC12 are respectively connected to one port of the three-way valve 14.

[0020] Specifically, the battery coolant circuit includes, in sequence according to the coolant flow direction, a battery water pump 15, a power battery 16, a battery plate heat exchanger Chiller 5 liquid side, and a five-way valve 17. The inlet end of the battery water pump 15 and the liquid-side outlet end of the battery plate heat exchanger Chiller 5 are respectively connected to one port of the five-way valve 17. A two-way shut-off valve 18 is provided between the battery water pump 15 and the five-way valve 17. A branch is provided between the battery water pump 15 and the two-way shut-off valve 18 and connected to the liquid side of the heater pump HeatEWP11 and the water-cooled condenser LCC2. A one-way valve 25 is provided on this branch. A branch is provided between the two-way shut-off valve 18 and the battery water pump 15 and connected to one port of the three-way valve 14.

[0021] Specifically, the electric drive coolant circuit includes, in sequence according to the coolant flow direction, an electric drive water pump MotEXP19, an electric drive assembly 20, a low-temperature radiator LTR21, and a five-way valve 17. The inlet end of the electric drive water pump 19 and the outlet end of the low-temperature radiator LTR21 are respectively connected to one port of the five-way valve 17. A branch is provided between the outlet end of the electric drive assembly 20 and the inlet end of the low-temperature radiator LTR21 and connected to one port of the five-way valve 17.

[0022] Specifically, an electronic fan 23 is provided on one side of the low-temperature heat sink LTR21.

[0023] Furthermore, the present invention achieves the following modes by switching valves: In single-air conditioning cooling mode: In the refrigerant circuit, the refrigerant enters the water-cooled condenser LCC2 from the outlet of compressor 1 without heat exchange, and then flows through shut-off valve 17 to enter the outdoor heat exchanger 3 to dissipate heat to the environment. At this time, shut-off valve 17 is open and shut-off valve 28 is closed. After exchanging heat with the environment, the refrigerant flows through check valve 124 and is throttled by expansion valve 19 before entering the indoor evaporator 4 for cooling. At this time, expansion valve 210 is closed. Finally, the refrigerant returns to the inlet of compressor 1 through the gas separator to complete the cycle.

[0024] Single-cell cooling and dual-cooling mode of battery air conditioning: The refrigerant circuit and the battery coolant circuit work together. The refrigerant circuit only needs to open the expansion valve 10 according to the battery heat dissipation requirements. The refrigerant flows through the battery plate heat exchanger chiiller 5 for heat exchange. In the battery coolant circuit, the two-way shut-off valve 18 is open, and the 2-3 connection 1, A, and B of the five-way valve 17 are closed. At this time, the coolant releases heat in the battery plate heat exchanger chiiller 5 and enters the power battery 16 cold plate for cooling through the battery water pump 15.

[0025] Air conditioning cooling and dehumidification mode: The refrigerant circuit and the heating coolant circuit work together. The refrigerant circuit operates in the same way as in the single air conditioning cooling mode. In the heating circuit, valves 1-2 of the three-way valve 14 are connected and valve 3 is closed. The coolant flows through the heater core pump 11 and then through the liquid side of the water-cooled condenser LCC2 to carry the excess cooling capacity into the heater core 13. The humid air is first cooled and dehumidified by the condenser fan 22 and then heated by the heater core 13 to the outlet air temperature required by the air conditioning system. When the temperature of the dry air after dehumidification by the evaporator 4 deviates significantly from the set outlet air temperature of the air conditioner, the power of the heater core pump 11 needs to be increased to increase the flow rate of the heating coolant circuit to compensate for the temperature deviation and achieve the goal of cooling and dehumidification.

[0026] Air conditioning cooling / dehumidification and battery cooling modes: The refrigerant circuit, heating coolant circuit, and battery coolant circuit work together. In air conditioning cooling / dehumidification mode, the two-way shut-off valve 18 is open, and valves 2 and 3 of the five-way valve 17 are connected. Expansion valve 2 10 adjusts in conjunction with expansion valve 1 9 according to the cooling capacity requirements of the power battery 16 and evaporator 4. When the power battery side prioritizes cooling, expansion valve 2 10 controls the chiller superheat corresponding to the target temperature of the power battery inlet water, while expansion valve 1 9 controls the subcooling at the outlet of the outdoor heat exchanger 3. Conversely, it controls the cooling capacity required by the passenger compartment. When the passenger compartment prioritizes cooling, expansion valve 1 9 controls the evaporator 4 outlet superheat corresponding to the target air outlet temperature of the air conditioner, while expansion valve 2 10 controls the subcooling at the outlet of the outdoor heat exchanger 3.

[0027] Battery waste heat recovery mode: The refrigerant circuit, heating coolant circuit, and battery coolant circuit work together. This mode is activated when the crew cabin has heating needs and there is excess battery heat. The compressor uses the excess heat from the power battery to be transferred to the heater core 13 via the coolant. The refrigerant is discharged from the outlet of compressor 1 to the refrigerant side of the water-cooled condenser LCC2 to heat the coolant. The first shut-off valve 7 is closed, the second shut-off valve 8 is open, and the first expansion valve 9 is closed. The refrigerant enters the battery plate heat exchanger chiiller 5 to absorb heat. At this time, the second expansion valve 10 controls the valve opening according to the subcooling degree of the outlet of the water-cooled condenser LCC2, and the refrigerant returns to the gas-liquid separator 6 to complete the cycle. The 2-3 terminals of the five-way valve 17 are connected, the two-way shut-off valve 18 is closed, the 1-2 terminals of the three-way valve 14 in the heating coolant circuit are connected, and the 3 terminal is closed. The battery coolant circuit and the heating coolant circuit complete self-circulation in their respective small circuits. In the battery coolant circuit, the coolant absorbs heat on the power battery side and releases heat on the liquid side of the battery plate heat exchanger chiiller 5. In the heating coolant circuit, the coolant absorbs heat on the liquid side of the water-cooled condenser LCC2 and releases heat in the heater core 13.

[0028] Electric drive plus battery waste heat recovery mode: The refrigerant circuit, heating coolant circuit, battery coolant circuit and electric drive coolant circuit work together. The principle of the refrigerant side is the same as that of battery waste heat recovery. In the heating coolant circuit, the 1-2 of the three-way valve 14 is connected and the 3 is closed. In the battery coolant circuit, the two-way shut-off valve 18 is open. The 1-3, 2-A and B of the five-way valve 17 are connected and closed. In the electric drive coolant circuit, the coolant flows from the electric drive water pump 19 through the electric drive assembly 20 to absorb heat. After passing through the A inlet and 2 outlet of the five-way valve 17, it is pumped into the power battery 16 cold plate to absorb heat. Heat is released on the liquid side of the battery plate heat exchanger chiiller 5 to heat the refrigerant. Finally, it returns to the electric drive water pump 19 through the 3 inlet and 1 outlet of the five-way valve 17 to complete the cycle.

[0029] Air conditioning heating and dehumidification mode: The refrigerant circuit, heating coolant circuit, and battery coolant circuit work together. This mode is mainly used in situations where there is excess heating capacity and high humidity in battery waste heat recovery mode or electric drive plus battery waste heat recovery mode. The refrigerant is discharged from the outlet of compressor 1 to the refrigerant side of the water-cooled condenser LCC2 to heat the coolant. The shut-off valve 28 is closed and the shut-off valve 17 is opened. The purpose is to release the excess heat to the low-temperature environment. After passing through the expansion valve 210, it enters the battery plate heat exchanger chiiller 5 to absorb heat. At this time, the opening of the expansion valve 210 is controlled according to the subcooling degree of the water-cooled condenser LCC2 outlet. When the heat dissipation demand of the electric drive assembly 20 is large, the electric drive coolant circuit enters the active cooling mode. At this time, the heat source of the water source heat pump is the battery plus electric drive. At this time, the 1-B phase and 2-3 phase of the five-way valve 17 are switched to the A-2 phase and 1-3 phase.

[0030] Electric drive natural cooling mode: In the electric drive coolant circuit, the 1-B terminals of the five-way valve 17 are connected. The coolant absorbs heat from the electric drive assembly 20 and releases heat to the low-temperature radiator LTR21. It then flows through the five-way valve 17 and the electric drive water 19 to complete the circulation.

[0031] See Figure 1 In combination with the principles of the above system mode, the layout cost of the actual vehicle is optimized. The black dotted box in the system diagram shows the pipes and components that need to be integrated into the integrated module. In addition, to facilitate the water replenishment and venting of the overall system, water replenishment and venting ports are set at the water pump inlets of the electric drive coolant circuit, battery coolant circuit and heating coolant circuit respectively. The three water replenishment and venting pipes are uniformly connected to the water replenishment and venting water tank.

[0032] The LCC is connected in series with the outdoor heat exchanger on the high-pressure side of the refrigerant. In the heat source mode of the heat pump, only the water source heat pump is used. At the same time, the five-way valve is used to increase the heat source on the low-pressure side of the water source heat pump from only the battery water circuit to the battery and electric drive circuit. The overall system makes more efficient use of the waste heat of the battery and electric drive, and the application scenarios of the waste heat recovery mode are expanded. At the same time, since the air source heat pump mode is eliminated, the expansion valve EXV in front of the outdoor heat exchanger can be eliminated on the high-pressure side, which effectively saves the cost of the integrated module and reduces the control difficulty of the software.

[0033] A three-way valve was added to connect the battery coolant circuit and the heating coolant circuit. An electric heater was added to the heating circuit to supplement the system's heat supply. The three-way valve provides supplemental heating to the heating element and the battery. This solution reduces the number of WPTCs in the battery coolant circuit while ensuring the battery's required heating capacity when the heat pump cannot operate in low-temperature environments. The battery can be heated by connecting it in series with the heating circuit via the WPTC, or it can be directly connected in series with the electric drive circuit to utilize the waste heat from the electric drive to heat the battery. This effectively reduces the cost of components and wiring harnesses. At the same time, the single PTC system increases the integration of the integrated module and reduces external piping, effectively saving layout space.

[0034] 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 integrated thermal management system for new energy pure electric vehicles, characterized in that: It includes a refrigerant circuit and a coolant circuit, wherein the refrigerant circuit and the coolant circuit are coupled and exchange heat through a heat exchange component; The coolant circuit includes a heating coolant circuit, a battery coolant circuit, and an electric drive coolant circuit. The battery coolant circuit and the electric drive coolant circuit are integrated and connected through a five-way valve (17), and the heating coolant circuit and the battery coolant circuit are connected through a three-way valve (14).

2. The integrated thermal management system for new energy pure electric vehicles as described in claim 1, characterized in that: The refrigerant circuit includes, in sequence according to the refrigerant flow direction, a compressor (1), a water-cooled condenser (2) on the refrigerant side, an outdoor heat exchanger (3), an evaporator (4), and a gas-liquid separator (6). The battery-type heat exchanger (5) on the refrigerant side is connected in parallel to both ends of the evaporator (4).

3. The integrated thermal management system for new energy pure electric vehicles as described in claim 2, characterized in that: A shut-off valve 1 (7) is connected in series between the outlet end of the water-cooled condenser (2) and the inlet end of the outdoor heat exchanger (3). A one-way valve 1 (24) is connected to the outlet end of the outdoor heat exchanger (3). The inlet end of a shut-off valve 2 (8) is connected between the outlet end of the water-cooled condenser (2) and the shut-off valve 1 (7). The outlet end of the shut-off valve 2 (8) is connected to the outlet end of the one-way valve 1 (24). An expansion valve (9) is connected in series between the outlet end of the one-way valve (24) and the inlet end of the evaporator (4). An expansion valve (10) is connected between the outlet end of the outdoor heat exchanger (3) and the inlet end of the expansion valve (9). The outlet end of the expansion valve (10) is connected to the refrigerant side inlet end of the water-cooled condenser (2).

4. The integrated thermal management system for new energy pure electric vehicles as described in claim 2, characterized in that: A condenser fan (22) is provided on one side of the evaporator (4).

5. The integrated thermal management system for new energy pure electric 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 (11), a water-cooled condenser (2) liquid side, a heater (12), a three-way valve (14) and a hot air core (13). The inlet end of the hot air core (13) and the outlet end of the heater (12) are respectively connected to one port of the three-way valve (14).

6. The integrated thermal management system for new energy pure electric vehicles as described in claim 1, characterized in that: The battery coolant circuit includes, in sequence according to the coolant flow direction, a battery water pump (15), a power battery (16), a battery plate heat exchanger (5) liquid side, and a five-way valve (17).

7. The integrated thermal management system for new energy pure electric vehicles as described in claim 6, characterized in that: The inlet end of the battery water pump (15) and the liquid-side outlet end of the battery plate heat exchanger (5) are respectively connected to one port of the five-way valve (17). A two-way shut-off valve (18) is provided between the battery water pump (15) and the five-way valve (17). A branch is provided between the five-way valve (17) and the two-way shut-off valve (18) and connected to the liquid side between the warm air water pump (11) and the water-cooled condenser (2). A one-way valve (25) is provided on this branch. A branch is provided between the two-way shut-off valve (18) and the battery water pump (15) and connected to one port of the three-way valve (14).

8. The integrated thermal management system for new energy pure electric 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 (19), an electric drive assembly (20), a low-temperature radiator LTR (21), and a five-way valve (17). The inlet end of the electric drive water pump (19) and the outlet end of the low-temperature radiator LTR (21) are respectively connected to one port of the five-way valve (17). A branch is provided between the outlet end of the electric drive assembly (20) and the inlet end of the low-temperature radiator LTR (21) and connected to one port of the five-way valve (17).

9. The integrated thermal management system for new energy pure electric vehicles as described in claim 8, characterized in that: An electronic fan (23) is provided on one side of the low-temperature heat sink LTR (21).

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