Dual split-flow thermal management system for electric vehicles

Abstract

The application provides an electric vehicle double-dividing flow heat management system related to the field of electric vehicle heat management, which comprises a refrigerant circuit, a cooling liquid circuit and a battery circuit, the refrigerant circuit is connected with the cooling liquid circuit and the battery circuit respectively, and the cooling liquid circuit is connected with the battery circuit; the refrigerant circuit comprises a gas-liquid separator, a compressor, a water-cooled condenser, a first stop valve, a first throttling mechanism, a first heat exchange device, a second throttling mechanism, a second heat exchange device, a one-way valve, a second stop valve, a third throttling mechanism and an evaporator; the refrigerant flowing through the first heat exchange device or / and the evaporator is returned to the compressor through the gas-liquid separator to complete refrigerant circulation. The application realizes heat pump heating, absorbs heat from air, fully utilizes waste heat, improves the energy efficiency of the heat management system, and the refrigerant circuit is convenient to configure into different working modes.

Description

Technical Field

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

[0002] Compared to traditional gasoline vehicles, all the heat in electric vehicles comes from the output of the battery. Therefore, reducing the energy consumption of the thermal management system and improving the energy utilization efficiency of the battery are of great significance to electric vehicles.

[0003] Heat pump air conditioning technology effectively utilizes ambient heat, resulting in an energy efficiency 2-3 times higher than traditional electric heating methods, making it highly suitable for electric vehicle thermal management. However, existing heat pump air conditioning systems primarily use heat pump technology to heat the passenger compartment, while battery heating in winter generally still relies on electric heating. Furthermore, current electric vehicle thermal management systems typically struggle to fully utilize the waste heat generated by the motor and electronic control system during operation, failing to achieve optimal energy utilization.

[0004] A search of existing patent literature revealed Chinese invention patent publication number CN111645511A, which discloses a dual-flow thermal management system for electric vehicles and an electric vehicle. Belonging to the automotive field, this system improves the energy utilization efficiency of the dual-flow thermal management system and reduces its manufacturing cost, thereby lowering the overall manufacturing cost of the electric vehicle. It includes an electric drive temperature control system, a battery temperature control system, and an air conditioning system. All three systems are communicatively connected to the vehicle's controller, which controls their respective operating states. This design utilizes the vehicle controller to simultaneously control all three systems, unlike the previous method of using separate controllers for each system. Summary of the Invention

[0005] To address the shortcomings of existing technologies, the purpose of this invention is to provide a dual-flow thermal management system for electric vehicles.

[0006] According to the present invention, a dual-flow thermal management system for electric vehicles includes a refrigerant circuit, a coolant circuit, and a battery circuit, wherein the refrigerant circuit is connected to the coolant circuit and the battery circuit respectively, and the coolant circuit is connected to the battery circuit.

[0007] The refrigerant circuit includes a gas-liquid separator, a compressor, a water-cooled condenser, a first shut-off valve, a first throttling mechanism, a first heat exchanger, a second throttling mechanism, a second heat exchanger, a one-way valve, a second shut-off valve, a third throttling mechanism, and an evaporator. One end of the gas-liquid separator is connected to the second heat exchanger, the second shut-off valve, and the evaporator, respectively. The other end of the gas-liquid separator is connected to the compressor. The compressor is connected to the water-cooled condenser. The water-cooled condenser is connected to the first shut-off valve and the first throttling mechanism, respectively. The first throttling mechanism is connected to the first heat exchanger. The first shut-off valve is connected to the second throttling mechanism and the one-way valve, respectively. The second throttling mechanism is connected to the second heat exchanger. The second heat exchanger is connected to the evaporator. The one-way valve is connected to the first heat exchanger, the second shut-off valve, and the third throttling mechanism, respectively. The third throttling mechanism is connected to the evaporator.

[0008] High-temperature and high-pressure superheated gaseous refrigerant flows out of the compressor, dissipates heat to the ambient air in the first heat exchange device and becomes subcooled liquid refrigerant. The liquid refrigerant flowing through the first heat exchange device flows through the second throttling mechanism and / or the third throttling mechanism. After being throttled and depressurized by the second throttling mechanism and / or the third throttling mechanism, the refrigerant flows into the evaporator. The refrigerant flowing through the first heat exchange device and / or the evaporator passes through the gas-liquid separator and returns to the compressor to complete the refrigerant cycle.

[0009] In some embodiments, the battery circuit includes a power battery, a fourth heat exchange device, a first water valve, a third water valve, and a first water pump. The power battery is connected to the fourth heat exchange device and the first water pump at both ends. The fourth heat exchange device is connected to the first water valve, a water-cooled condenser, and a coolant circuit. The first water valve is connected to the second heat exchange device, the coolant circuit, and the third water valve. The third water valve is connected to the first water pump.

[0010] In some embodiments, the coolant circuit includes a drive motor, a motor control unit, a third heat exchange device, a fourth water valve, a second water valve, a fifth water valve, a heater core, a third water pump, an electric heater, and a second water pump. The motor control unit is connected to the drive motor, the drive motor is connected to the third heat exchange device and the fourth water valve, the fourth water valve is connected to the third heat exchange device and the third water valve, the third water valve is connected to the first water valve and the second water valve, the second water valve is connected to the first water valve, the second water pump, and the second heat exchange device, and the second water pump is connected to the motor control unit.

[0011] The fifth water valve is connected to the heating core, the third water pump and the fourth heat exchange device respectively. The heating core is connected to the water-cooled condenser and the fourth heat exchange device respectively. The third water pump is connected to the first heat exchange device, the third throttling mechanism and the electric heater respectively. The electric heater is connected to the water-cooled condenser.

[0012] In some embodiments, a temperature damper is also included, wherein the temperature damper, the evaporator, and the warm air core are connected inside the air conditioning unit.

[0013] In some embodiments, the first water valve, the second water valve, and the third water valve are four-way water valves;

[0014] The connection ends of the first water valve are respectively represented as end 151, end 152, end 153 and end 154. End 151 is connected to the first heat exchange device, end 152 is connected to the second water valve, end 153 is connected to the third water valve, and end 154 is connected to the fourth heat exchange device.

[0015] The connection ends of the second water valve are respectively represented as end 221, end 222, end 223 and end 224. End 221 is connected to the first heat exchange device, end 222 is connected to the second water pump, end 223 is connected to the third water valve, and end 224 is connected to end 152 of the first water valve.

[0016] The connection terminals of the third water valve are respectively represented as terminal 161, terminal 162, terminal 163 and terminal 164. Terminal 161 is connected to terminal 153 of the first water valve, terminal 162 is connected to terminal 223 of the second water valve, terminal 163 is connected to the fourth water valve, and terminal 164 is connected to the first water pump.

[0017] In some embodiments, the fourth and fifth water valves are three-way water valves;

[0018] The connection ends of the fourth water valve are respectively represented as end 211, end 212 and end 213. End 211 is connected to the third heat exchange device, end 212 is connected to the drive motor, and end 213 is connected to end 163 of the third water valve.

[0019] The connection ends of the fifth water valve are designated as end 231, end 232, and end 233. End 231 is connected to the third water pump, end 232 is connected to the warm air core, and end 233 is connected to the fourth heat exchange device.

[0020] In some embodiments, the motor control unit controls the switching of the first shut-off valve, the first throttling mechanism, the second throttling mechanism, the one-way valve, the second shut-off valve, the third throttling mechanism, the first water valve, the third water valve, the fourth water valve, the second water valve, and the fifth water valve, thereby driving the coolant circuit to switch between cooling mode, heating mode, passenger compartment heating battery cooling mode, dehumidification mode, external heat exchanger defrosting mode, motor heating battery mode, and motor battery heat dissipation mode.

[0021] In some embodiments, when in cooling mode, the third water pump, the fifth water valve, the first shut-off valve, and the second shut-off valve are closed, and the first throttling mechanism, the second throttling mechanism, the third throttling mechanism, the first water pump, the second water pump, and the third water pump are opened. The 151 and 154 terminals of the first water valve are connected, the 152 and 153 terminals of the second water valve are connected, the 221 and 224 terminals of the second water valve are connected, the 222 and 223 terminals of the third water valve are connected, the 161 and 164 terminals of the third water valve are connected, the 162 and 163 terminals of the third water valve are connected, and the 211 and 213 terminals of the fourth water valve are connected, thereby cooling the power battery and / or the drive motor.

[0022] Alternatively, when in motor battery cooling mode, the refrigerant circuit, the fifth water valve, and the third water pump are closed, and the first and second water pumps are turned on. The first water valve's terminals 153 and 154 are connected, the second water valve's terminals 222 and 223 are connected, the third water valve's terminals 161 and 162, 163 and 164 are connected, and the fourth water valve's terminals 211 and 213 are connected to cool the power battery.

[0023] Alternatively, when in the crew compartment heating battery cooling mode, the one-way valve and the third throttling mechanism are closed, and the first water pump, the second water pump, the third water pump, the first throttling mechanism, the second throttling mechanism, the first shut-off valve, and the second shut-off valve are opened. The 151 and 154 terminals of the first water valve are connected, as are the 152 and 153 terminals. The 221 and 224 terminals of the second water valve are connected, as are the 222 and 223 terminals. The 161 and 164 terminals of the third water valve are connected, as are the 162 and 163 terminals. The 211 and 213 terminals of the fourth water valve are connected. Therefore, the 231 and 232 terminals of the fifth water valve are connected.

[0024] In some embodiments, when in heating mode, the one-way valve and the third throttling mechanism are closed, and the first water pump, the second water pump, the third water pump, the first throttling mechanism, and the second throttling mechanism are turned on. The 151 and 152 terminals of the first water valve are connected, the 153 and 154 terminals are connected, the 221 and 222 terminals of the second water valve are connected, the 223 and 224 terminals of the second water valve are connected, the 161 and 164 terminals of the third water valve are connected, the 162 and 163 terminals of the third water valve are connected, the 212 and 213 terminals of the fourth water valve are connected, and the 231, 232, and 233 terminals of the fifth water valve are all open.

[0025] Alternatively, when in heating mode, close the check valve, the third throttling mechanism, the first throttling mechanism, and the second shut-off valve, and turn on the first water pump, the second water pump, the third water pump, and the second throttling mechanism. Connect the 151 and 152 terminals of the first water valve, connect the 153 and 154 terminals of the second water valve, connect the 221 and 222 terminals of the second water valve, connect the 223 and 224 terminals of the third water valve, connect the 161 and 164 terminals of the third water valve, connect the 162 and 163 terminals of the fourth water valve, connect the 211 and 213 terminals of the fourth water valve, and connect the 231, 232, and 233 terminals of the fifth water valve.

[0026] Alternatively, in the motor-heated battery mode, the refrigerant circuit, the third water pump, and the fifth water valve are shut off, while the first and second water pumps are turned on. Terminals 154 and 153 of the first water valve are connected, terminals 222 and 223 of the second water valve are connected, terminals 161 and 162, terminals 163 and 164 of the third water valve are connected, and terminals 212 and 213 of the fourth water valve are connected.

[0027] In some embodiments, when in dehumidification mode, the first and second shut-off valves are closed, and the check valve, the first water pump, the second water pump, the third water pump, the first throttling mechanism, the second throttling mechanism, and the third throttling mechanism are opened. The 151 and 152 terminals of the first water valve are connected, the 221 and 222 terminals and the 223 and 224 terminals of the second water valve are connected, the 162 and 163 terminals of the third water valve are connected, the 212 and 213 terminals of the fourth water valve are connected, and the 231, 232, and 233 terminals of the fifth water valve are all open.

[0028] Alternatively, when in the defrosting mode of the external heat exchanger, the third throttling mechanism, the first shut-off valve, and the second shut-off valve are closed, and the check valve, the second throttling mechanism, the first water pump, the second water pump, and the third water pump are opened. The 151 and 154 terminals of the first water valve are connected, as are the 152 and 153 terminals. The 221 and 224 terminals of the second water valve are connected, as are the 222 and 223 terminals. The 161 and 164 terminals of the third water valve are connected, as are the 162 and 163 terminals. The 211 and 213 terminals of the fourth water valve are connected. The 231, 232, and 233 terminals of the fifth water valve are all open.

[0029] Compared with the prior art, the present invention has the following beneficial effects:

[0030] 1) This invention can use a heat pump to heat the battery, which is more energy-efficient than the commonly used electric heating method. The heat pump system can absorb heat directly from the air through the external evaporator or through the coolant circuit of the external radiator, thereby solving the problem that the heat pump cannot continue to be used for cooling after the external evaporator is frosted.

[0031] 2) This invention can fully and rationally utilize the waste heat generated by the motor, motor control unit, and even the battery during operation to provide heat for the vehicle;

[0032] 3) This invention can also directly use a fan and heat sink to dissipate heat from the battery without turning on the compressor, thereby further improving the energy efficiency of the thermal management system;

[0033] 4) The refrigerant circuit of the present invention adopts a dual condenser design, which is convenient to be configured into different working modes. The coolant circuit is also flexible in structure and can be easily configured into different working modes to make the system energy efficiency optimal. Attached Figure Description

[0034] Other features, objects, and advantages of the present invention will become more apparent from the following detailed description of non-limiting embodiments with reference to the accompanying drawings:

[0035] Figure 1 Schematic diagram of the present invention

[0036] Figure 2 Schematic diagram of the refrigerant circuit of the present invention;

[0037] Figure 3 A schematic diagram of the operation of this invention in cooling mode;

[0038] Figure 4 A schematic diagram of the operation of the present invention in a heating mode;

[0039] Figure 5 A schematic diagram of the operation of the present invention in another heating mode;

[0040] Figure 6 A schematic diagram of the operation of this invention in the crew cabin heating battery cooling mode;

[0041] Figure 7 A schematic diagram of the operation of this invention in the dehumidification mode of the passenger cabin;

[0042] Figure 8 A schematic diagram of the operation of the present invention in the defrosting mode of the external heat exchanger;

[0043] Figure 9 A schematic diagram of the operation of the coolant circuit in the motor-heated battery mode of this invention;

[0044] Figure 10 A schematic diagram of the operation of the coolant circuit in the battery-motor heat dissipation mode of this invention.

[0045] Numbering on the map:

[0046] Gas-liquid separator 1, compressor 2, water-cooled condenser 3, first shut-off valve 4, first throttling mechanism 5, first heat exchanger 6, second throttling mechanism 7, second heat exchanger 8, one-way valve 9, second shut-off valve 10, third throttling mechanism 11, evaporator 12, power battery 13, fourth heat exchanger 14, first water valve 15, 151 end, 152 end, 153 end, 154 end, third water valve 16, 161 end, 162 end, 1 Terminal 63, Terminal 164, First water pump 17, Drive motor 18, Motor control unit 19, Third heat exchange device 20, Fourth water valve 21, Terminal 211, Terminal 212, Terminal 213, Second water valve 22, Terminal 221, Terminal 222, Terminal 223, Terminal 224, Fifth water valve 23, Terminal 231, Terminal 232, Terminal 233, Warm air core 24, Third water pump 25, Electric heater 26, Second water pump 27, Temperature damper 28. Detailed Implementation

[0047] The present invention will now be described in detail with reference to specific embodiments. These embodiments will help those skilled in the art to further understand the present invention, but do not limit the invention in any way. It should be noted that those skilled in the art can make several changes and improvements without departing from the concept of the present invention. These all fall within the protection scope of the present invention.

[0048] Example

[0049] This invention provides a dual-flow thermal management system for electric vehicles, such as... Figure 1-2 As shown, it includes a refrigerant circuit, a coolant circuit, a battery circuit, and a temperature damper 28. The refrigerant circuit is connected to the coolant circuit and the battery circuit, and the coolant circuit is connected to the battery circuit. The temperature damper 28, the evaporator 12, and the heater core 24 are connected inside the air conditioning unit.

[0050] The refrigerant circuit includes a gas-liquid separator 1, a compressor 2, a water-cooled condenser 3, a first shut-off valve 4, a first throttling mechanism 5, a first heat exchange device 6, a second throttling mechanism 7, a second heat exchange device 8, a one-way valve 9, a second shut-off valve 10, a third throttling mechanism 11, and an evaporator 12. One end of the gas-liquid separator 1 is connected to the second heat exchange device 8, the second shut-off valve 10, and the evaporator 12, respectively. The other end of the gas-liquid separator 1 is connected to the compressor 2. The compressor 2 is connected to the water-cooled condenser 3. The water-cooled condenser 3 is connected to the first shut-off valve 4 and the first throttling mechanism 5, respectively. The first throttling mechanism 5 is connected to the first heat exchange device 6. The first shut-off valve 4 is connected to the second throttling mechanism 7 and the one-way valve 9, respectively. The second throttling mechanism 7 is connected to the second heat exchange device 8, and the second heat exchange device 8 is connected to the evaporator 12. The one-way valve 9 is connected to the first heat exchange device 6, the second shut-off valve 10, and the third throttling mechanism 11, respectively. The third throttling mechanism 11 is connected to the evaporator 12. High-temperature and high-pressure superheated gaseous refrigerant flows out of compressor 2, dissipates heat to the ambient air in the first heat exchange device 6 and becomes subcooled liquid refrigerant. The liquid refrigerant flowing through the first heat exchange device 6 flows through the second throttling mechanism 7 and / or the third throttling mechanism 11 respectively. After being throttled and depressurized by the second throttling mechanism 7 and / or the third throttling mechanism 11, the refrigerant flows into evaporator 12. The refrigerant flowing through the first heat exchange device 6 and / or the evaporator 12 passes through the gas-liquid separator 1 and then returns to compressor 2 to complete the refrigerant cycle.

[0051] The battery circuit includes a power battery 13, a fourth heat exchange device 14, a first water valve 15, a third water valve 16, and a first water pump 17. The two ends of the power battery 13 are connected to the fourth heat exchange device 14 and the first water pump 17, respectively. The fourth heat exchange device 14 is connected to the first water valve 15, the water-cooled condenser 3, and the coolant circuit. The first water valve 15 is connected to the second heat exchange device 8, the coolant circuit, and the third water valve 16, respectively. The third water valve 16 is connected to the first water pump 17.

[0052] The coolant circuit includes a drive motor 18, a motor control unit 19, a third heat exchanger 20, a fourth water valve 21, a second water valve 22, a fifth water valve 23, a heater core 24, a third water pump 25, an electric heater 26, and a second water pump 27. The motor control unit 19 is connected to the drive motor 18. The drive motor 18 is connected to the third heat exchanger 20 and the fourth water valve 21. The fourth water valve 21 is connected to the third heat exchanger 20 and the third water valve 16. The third water valve 16 is connected to the first water valve 15 and the second water valve 22. The second water valve 22 is connected to the first water valve 15, the second water pump 27, and the second heat exchanger 8. The second water pump 27 is connected to the motor control unit 19. The fifth water valve 23 is connected to the heater core 24, the third water pump 25, and the fourth heat exchanger 14. The heater core 24 is connected to the water-cooled condenser 3 and the fourth heat exchanger 14. The third water pump 25 is connected to the electric heater 26, and the electric heater 26 is connected to the water-cooled condenser 3.

[0053] The first water valve 15, the second water valve 22, and the third water valve 16 are four-way valves. The connection ends of the first water valve 15 are designated as ends 151, 152, 153, and 154, respectively. End 151 is connected to the first heat exchanger 6, end 152 is connected to the second water valve 22, end 153 is connected to the third water valve 16, and end 154 is connected to the fourth heat exchanger 14. The connection ends of the second water valve 22 are designated as ends 221, 222, 223, and 224, respectively. Terminal 221 is connected to the first heat exchanger 6, terminal 222 is connected to the second water pump 27, terminal 223 is connected to the third water valve 16, and terminal 224 is connected to terminal 152 of the first water valve 15. The connection terminals of the third water valve 16 are respectively represented as terminal 161, terminal 162, terminal 163, and terminal 164. Terminal 161 is connected to terminal 153 of the first water valve 15, terminal 162 is connected to terminal 223 of the second water valve 22, terminal 163 is connected to the fourth water valve 21, and terminal 164 is connected to the first water pump 17. The fourth water valve 21 and the fifth water valve 23 are three-way water valves. The connection ends of the fourth water valve 21 are respectively labeled as end 211, end 212 and end 213. End 211 is connected to the third heat exchange device 20, end 212 is connected to the drive motor 18, and end 213 is connected to end 163 of the third water valve 16. The connection ends of the fifth water valve 23 are respectively labeled as end 231, end 232 and end 233. End 231 is connected to the third water pump 25, end 232 is connected to the warm air core 24, and end 233 is connected to the fourth heat exchange device 14.

[0054] The motor control unit 19 controls the opening and closing of the first shut-off valve 4, the first throttling mechanism 5, the second throttling mechanism 7, the one-way valve 9, the second shut-off valve 10, the third throttling mechanism 11, the first water valve 15, the third water valve 16, the fourth water valve 21, the second water valve 22, and the fifth water valve 23, thereby driving the coolant circuit to switch between cooling mode, heating mode, crew compartment heating battery cooling mode, dehumidification mode, external heat exchanger defrosting mode, motor heating battery mode, and motor battery heat dissipation mode.

[0055] Working principle:The second throttling mechanism 7 and the third throttling mechanism 11 can be in a closed or throttling state to regulate the refrigerant flow. The first throttling mechanism 5 can be in a closed, throttling, or fully open state; when in the fully open state, it functions as a connecting pipe and has no throttling effect. The first shut-off valve 4, the second shut-off valve 10, the one-way valve 9, the first throttling mechanism 5, the second throttling mechanism 7, and the third throttling mechanism 11 work together to control the operating mode of the refrigerant circuit. The electric heater 26 provides heat to the system when the heat pump's heating capacity is insufficient or the heat pump cannot operate. The four-way water valve and the three-way water valve control the operating mode of the coolant circuit. The first heat exchange device 6 is used for heat exchange between the refrigerant and ambient air; specifically, in cooling mode, it acts as a condenser releasing heat to the air, and in heating mode, it acts as an evaporator absorbing heat from the environment. The second heat exchange device 8 is used for heat exchange between the refrigerant and coolant circuits; specifically, it uses the low-temperature refrigerant to lower the coolant temperature or absorbs heat from the coolant circuit. The third heat exchange device 20 is used for heat exchange between the coolant and ambient air. The fourth heat exchange device 14 is used for heat exchange between coolants, specifically for the coolant in one branch to heat the coolant in another branch.

[0056] like Figure 3As shown, in cooling mode, the first throttling mechanism 5 is fully open, allowing the first heat exchange device 6 to function as an external condenser. The first shut-off valve 4 is closed, the second shut-off valve 10 is closed, and one or both of the second throttling mechanism 7 and the third throttling mechanism 11 can be in a throttling state. The third water pump 25 is not working, therefore, no heat exchange occurs between the refrigerant and coolant in the water-cooled condenser 3; it only serves as a section of the refrigerant flow circuit. The high-temperature, high-pressure superheated gaseous refrigerant flows out from the compressor 2, dissipates heat to the ambient air in the first heat exchange device 6, and becomes a subcooled liquid refrigerant. The liquid refrigerant flowing through the first heat exchange device 6 can flow through the second throttling mechanism 7 and the third throttling mechanism 11 as needed. When the power battery 13 needs cooling, the second throttling mechanism 7 opens, connecting terminals 151 and 154, and terminals 152 and 153 of the first water valve 15; terminals 221 and 224, and terminals 222 and 223 of the second water valve 22; terminals 161 and 164, and terminals 162 and 163 of the third water valve 16; and terminals 211 and 213 of the fourth water valve 21. After the refrigerant is throttled, depressurized, and cooled by the second throttling mechanism 7, it absorbs heat from the coolant in the battery circuit within the first heat exchange device 6, thereby cooling the battery. When the passenger compartment needs cooling, the third throttling mechanism 11 opens. After the refrigerant is throttled, depressurized, and cooled by the third throttling mechanism 11, it absorbs heat from the air in the passenger compartment within the evaporator 12, thus cooling the passenger compartment. At this time, the temperature damper 28 is generally in the fully cooled position. The refrigerant flowing through the first heat exchanger 6 or the evaporator 12 passes through the gas-liquid separator 1 and then returns to the compressor 2, thus completing the refrigerant cycle.

[0057] like Figure 4As shown, in a heating mode, the first throttling mechanism 5 is in a throttling state, causing the first heat exchange device 6 to function as an external evaporator. The first shut-off valve 4 can be opened, the second shut-off valve 10 is open, the second throttling mechanism 7 can be in a throttling state, and the third throttling mechanism 11 is closed. The third water pump 25 is activated, and the water-cooled condenser 3 operates, allowing the coolant circuit to absorb heat from the refrigerant circuit flowing through the water-cooled condenser 3 to heat the passenger compartment or battery. The high-temperature, high-pressure superheated gaseous refrigerant flows out from the compressor 2, releases heat to the coolant in the water-cooled condenser 3, and condenses into liquid refrigerant. The liquid refrigerant flowing through the water-cooled condenser 3 is throttled, depressurized, and cooled by the first throttling mechanism 5, thereby absorbing heat from the external environment through the first heat exchange device 6. If necessary, the liquid refrigerant flowing through the water-cooled condenser 3 can also flow through the second throttling mechanism 7 to recover the waste heat generated by the motor and motor control unit during operation. At this time, the 151 and 152 ends of the first water valve 15 are connected, the 153 and 154 ends are connected, the 221 and 222 ends of the second water valve 22 are connected, the 223 and 224 ends are connected, the 161 and 164 ends of the third water valve 16 are connected, the 162 and 163 ends are connected, and the 212 and 213 ends of the fourth water valve 21 are connected. After the refrigerant is throttled, depressurized, and cooled by the second throttling mechanism 7, it absorbs the heat from the circuit of the drive motor 18 and the motor control unit 19 through the second heat exchange device 8. The third water pump 25 is activated. Depending on the needs, terminals 231 and 232, 231 and 233, or both 231 and 232 / 233 of the fifth water valve 23 can be connected. This allows the heat absorbed by the refrigerant in the water-cooled condenser 3 to be released into the passenger compartment via the heater core 24 for heating. Alternatively, the second heat exchanger 8 can heat the coolant in the battery circuit to heat the power battery 13. When heating the passenger compartment, the temperature damper 28 is in a fully heated state. When heating the power battery 13, the first water pump 17 is activated.

[0058] Figure 4 In one heating mode demonstrated, the system primarily absorbs heat from the external environment through the first heat exchanger 6. When the ambient humidity is high, this method easily leads to frost formation on the surface of the first heat exchanger 6. If the frost buildup is severe, the heat pump system cannot operate, and heat must be provided via electric heating. This system offers an alternative solution. Figure 5 Another heating mode is demonstrated for continued heat pump heating even when severe frosting occurs in the first heat exchanger 6. In this mode, the first throttling mechanism 5 is closed, terminals 211 and 213 of the fourth water valve 21 are connected, and the remaining parts are connected to... Figure 4The first heating mode is the same. In this mode, the refrigerant circuit absorbs heat from the battery circuit through the second heat exchanger 8, while the low-temperature coolant circuit continues to absorb heat from the external environment through the third heat exchanger 20, thus ensuring the normal operation of the heat pump system. Unlike the cooling mode, in this heating mode, the third heat exchanger 20 is used to absorb heat from the ambient air.

[0059] like Figure 6 When in the crew compartment heating battery cooling mode, in this mode, terminals 151 and 154 of the first water valve 15 are connected, and terminals 152 and 153 are connected; terminals 221 and 224 of the second water valve 22 are connected, and terminals 222 and 223 are connected; terminals 161 and 164 of the third water valve 16 are connected, and terminals 162 and 163 are connected. The first shut-off valve 4 is open and the second throttling mechanism 7 is in a throttling state, allowing the refrigerant to cool the battery circuit through the second heat exchange device 8. The first throttling mechanism 5 is in a throttling state, thereby absorbing heat from the external environment. The second shut-off valve 10 is open, and the third throttling mechanism 11 is closed. The third water pump 25 is turned on, so terminals 231 and 232 of the fifth water valve 23 are connected, and the heat absorbed by the refrigerant from the water-cooled condenser 3 in the coolant circuit can be released to the crew compartment for heating through the heater core 24.

[0060] like Figure 7 When in dehumidification mode, the first shut-off valve 4 and the second shut-off valve 10 are closed, and the first throttling mechanism 5 is in a fully open state, allowing the first heat exchange device 6 to function as an external condenser. The third throttling mechanism 11 is in a throttling state, allowing the refrigerant to exchange heat with the air flowing through the evaporator 12 after being depressurized and cooled by the third throttling mechanism 11, thereby cooling and dehumidifying the passenger compartment. The third water pump 25 is turned on, and the 231 and 232 ends of the fifth water valve 23 are connected, allowing the air, which is at a lower temperature after passing through the evaporator 12, to be reheated by the heater core 24 into air with a suitable temperature and lower humidity before entering the passenger compartment. The second throttling mechanism 7 can be opened as needed. At this time, terminals 151 and 152 of the first water valve 15 are connected, terminals 221 and 222, and terminals 223 and 224 of the second water valve 22 are connected, and terminals 162 and 163 of the third water valve 16 are connected. This allows the refrigerant circuit to absorb the waste heat generated by the drive motor 18 and motor control unit 19 during operation through the second heat exchange device 8. In this mode, the temperature damper 28 can be adjusted according to the heating requirements of the passenger compartment.

[0061] When the ambient humidity is high, the system operating in heat pump mode is prone to frost buildup on the external heat exchanger. If the frost buildup is severe, defrosting is required. Figure 8As shown, when in the external heat exchanger defrosting mode, the first shut-off valve 4 and the second shut-off valve 10 are closed, and the first throttling mechanism 5 is in a fully open state, allowing the first heat exchanger 6 to function as an external condenser. The high-temperature refrigerant from the compressor 2 passes through the first heat exchanger 6 to achieve the defrosting function. The second throttling mechanism 7 is in a throttling state, with terminals 151 and 154 of the first water valve 15 connected, terminals 152 and 153 connected, terminals 221 and 224 of the second water valve 22 connected, and terminals 161 and 164 of the third water valve 16 connected. The refrigerant circuit absorbs heat from the power battery 13 through the second heat exchanger 8. The third water pump 25 is turned on, terminals 231 and 232 of the fifth water valve 23 are connected, and the electric heater 26 is turned on, thereby providing heat to the passenger compartment through the heater core 24.

[0062] The electric vehicle drive motor 18, motor control unit 19, and power battery 13 generate heat during operation. Utilizing this heat can effectively improve thermal management efficiency because it can reduce the energy consumption of the electric heater 26 or compressor 2. Figure 9 As shown, when in the motor-heated battery mode, i.e., the coolant circuit operation mode in which the drive motor 18 and motor control unit 19 heat the power battery 13. The refrigerant circuit, the third water pump 25 and the fifth water valve 23 are closed, and the first water pump 17 and the second water pump 27 are opened. The 151 and 153 terminals of the first water valve 15 are connected, the 222 and 223 terminals of the second water valve 22 are connected, the 161 and 162 terminals and the 163 and 164 terminals of the third water valve 16 are connected, and the 212 and 213 terminals of the fourth water valve 21 are connected.

[0063] When components such as the drive motor 18, motor control unit 19, and power battery 13 become too hot, they need to be cooled to ensure their normal operation. Cooling of the drive motor 18 and motor control unit 19 is achieved through a third heat exchange device 20, such as... Figure 3 As shown. There are two ways to cool the power battery 13, one of which is as follows: Figure 3 As shown, the power battery 13 is cooled by refrigerant flowing through the second heat exchanger 8. This method is generally used when the ambient temperature is high. When the ambient temperature is low, heat can be dissipated directly to the outside environment through the third heat exchanger 20, such as... Figure 10 As shown, the refrigerant circuit, the fifth water valve 23, and the third water pump 25 are closed, while the first water pump 17 and the second water pump 27 are turned on. Terminals 153 and 154 of the first water valve 15 are connected, as are terminals 222 and 223 of the second water valve 22. Terminals 161 and 162, and terminals 163 and 164 of the third water valve 16 are connected, and terminals 211 and 213 of the fourth water valve 21 are connected, thus cooling the power battery 13. At this time, the compressor 2 does not need to be turned on, thereby achieving energy saving.

[0064] In the description of this application, it should be understood that the terms "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application.

[0065] Specific embodiments of the present invention have been described above. It should be understood that the present invention is not limited to the specific embodiments described above, and those skilled in the art can make various changes or modifications within the scope of the claims, which do not affect the essence of the present invention. Unless otherwise specified, the embodiments and features described in this application can be arbitrarily combined with each other.

Claims

1. A control method for a dual-flow thermal management system for electric vehicles, characterized in that, It includes a refrigerant circuit, a coolant circuit, and a battery circuit. The refrigerant circuit is connected to the coolant circuit and the battery circuit, respectively, and the coolant circuit is connected to the battery circuit. The refrigerant circuit includes a gas-liquid separator (1), a compressor (2), a water-cooled condenser (3), a first shut-off valve (4), a first throttling mechanism (5), a first heat exchange device (6), a second throttling mechanism (7), a second heat exchange device (8), a one-way valve (9), a second shut-off valve (10), a third throttling mechanism (11), and an evaporator (12). One end of the gas-liquid separator (1) is connected to the second heat exchange device (8), the second shut-off valve (10), and the evaporator (12), respectively. The other end of the gas-liquid separator (1) is connected to the compressor (2), and the compressor (2) is connected to the water-cooled condenser (3). The water-cooled condenser (3) is connected to the first shut-off valve (4) and the first throttling mechanism (5) respectively. The first throttling mechanism (5) is connected to the first heat exchange device (6). The first shut-off valve (4) is connected to the second throttling mechanism (7) and the one-way valve (9) respectively. The second throttling mechanism (7) is connected to the second heat exchange device (8). The second heat exchange device (8) is connected to the evaporator (12). The one-way valve (9) is connected to the first heat exchange device (6), the second shut-off valve (10) and the third throttling mechanism (11) respectively. The third throttling mechanism (11) is connected to the evaporator (12). The high-temperature and high-pressure superheated gaseous refrigerant flows out from the compressor (2), dissipates heat to the ambient air in the first heat exchange device (6) and becomes a subcooled liquid refrigerant. The liquid refrigerant flowing through the first heat exchange device (6) flows through the second throttling mechanism (7) and / or the third throttling mechanism (11). After being throttled and depressurized by the second throttling mechanism (7) and / or the third throttling mechanism (11), the refrigerant flows into the evaporator (12). The refrigerant flowing through the first heat exchange device (6) and / or the evaporator (12) passes through the gas-liquid separator (1) and returns to the compressor (2) to complete the refrigerant cycle. The battery circuit includes a power battery (13), a fourth heat exchange device (14), a first water valve (15), a third water valve (16), and a first water pump (17). The two ends of the power battery (13) are respectively connected to the fourth heat exchange device (14) and the first water pump (17). The fourth heat exchange device (14) is connected to the first water valve (15), the water-cooled condenser (3), and the coolant circuit. The first water valve (15) is respectively connected to the second heat exchange device (8), the coolant circuit, and the third water valve (16). The third water valve (16) is connected to the first water pump (17). The coolant circuit includes a drive motor (18), a motor control unit (19), a third heat exchange device (20), a fourth water valve (21), a second water valve (22), a fifth water valve (23), a heater core (24), a third water pump (25), an electric heater (26), and a second water pump (27). The motor control unit (19) is connected to the drive motor (18). The drive motor (18) is connected to the third heat exchange device (20) and the fourth water valve (21). The fourth water valve (21) is connected to the third heat exchange device (20) and the third water valve (16). The third water valve (16) is connected to the first water valve (15) and the second water valve (22). The second water valve (22) is connected to the first water valve (15), the second water pump (27), and the second heat exchange device (8). The second water pump (27) is connected to the motor control unit (19). The fifth water valve (23) is connected to the warm air core (24), the third water pump (25) and the fourth heat exchange device (14) respectively. The warm air core (24) is connected to the water-cooled condenser (3) and the fourth heat exchange device (14) respectively. The third water pump (25) is connected to the electric heater (26). The electric heater (26) is connected to the water-cooled condenser (3). The first water valve (15), the second water valve (22), and the third water valve (16) are four-way water valves; The connection ends of the first water valve (15) are respectively referred to as end 151, end 152, end 153 and end 154. End 151 is connected to the first heat exchange device (6), end 152 is connected to the second water valve (22), end 153 is connected to the third water valve (16), and end 154 is connected to the fourth heat exchange device (14). The connection ends of the second water valve (22) are respectively referred to as end 221, end 222, end 223 and end 224. End 221 is connected to the first heat exchange device (6), end 222 is connected to the second water pump (27), end 223 is connected to the third water valve (16), and end 224 is connected to end 152 of the first water valve (15). The connection ends of the third water valve (16) are respectively represented as end 161, end 162, end 163 and end 164. End 161 is connected to end 153 of the first water valve (15), end 162 is connected to end 223 of the second water valve (22), end 163 is connected to the fourth water valve (21), and end 164 is connected to the first water pump (17). The fourth water valve (21) and the fifth water valve (23) are three-way water valves; The connection ends of the fourth water valve (21) are respectively represented as end 211, end 212 and end 213. End 211 is connected to the third heat exchange device (20), end 212 is connected to the drive motor (18), and end 213 is connected to end 163 of the third water valve (16). The connection ends of the fifth water valve (23) are respectively referred to as end 231, end 232 and end 233. End 231 is connected to the third water pump (25), end 232 is connected to the warm air core (24), and end 233 is connected to the fourth heat exchange device (14). When in heating mode, the one-way valve (9) and the third throttling mechanism (11) are closed, and the first water pump (17), the second water pump (27), the third water pump (25), the first throttling mechanism (5) and the second throttling mechanism (7) are turned on. The 151 and 152 ends of the first water valve (15) are connected, and the 153 and 154 ends are connected. The 221 and 222 ends of the second water valve (22) are connected, and the 223 and 224 ends are connected. The 161 and 164 ends of the third water valve (16) are connected, and the 162 and 163 ends are connected. The 212 and 213 ends of the fourth water valve (21) are connected. The 231, 232 and 233 ends of the fifth water valve (23) are all connected. Alternatively, when in heating mode, close the one-way valve (9), the third throttling mechanism (11), the first throttling mechanism (5), and the second shut-off valve (10), and turn on the first water pump (17), the second water pump (27), the third water pump (25), and the second throttling mechanism (7). The 151 and 152 ends of the first water valve (15) are connected, and the 153 and 154 ends are connected. The 221 and 222 ends of the second water valve (22) are connected, and the 223 and 224 ends are connected. The 161 and 164 ends of the third water valve (16) are connected, and the 162 and 163 ends are connected. The 211 and 213 ends of the fourth water valve (21) are connected. The 231, 232, and 233 ends of the fifth water valve (23) are all connected. Alternatively, in the motor-heated battery mode, the refrigerant circuit, the third water pump (25), and the fifth water valve (23) are turned off, and the first water pump (17) and the second water pump (27) are turned on. The 154 and 153 terminals of the first water valve (15) are connected, the 222 and 223 terminals of the second water valve (22) are connected, the 161 and 162 terminals of the third water valve (16) are connected, the 163 and 164 terminals are connected, and the 212 and 213 terminals of the fourth water valve (21) are connected.

2. The control method for the dual-flow thermal management system of an electric vehicle according to claim 1, characterized in that, It also includes a temperature damper (28), the temperature damper (28), the evaporator (12) and the warm air core (24) connected inside the air conditioning unit.

3. The control method for the dual-flow thermal management system of an electric vehicle according to any one of claims 1-2, characterized in that, The motor control unit (19) controls the opening and closing of the first shut-off valve (4), the first throttling mechanism (5), the second throttling mechanism (7), the one-way valve (9), the second shut-off valve (10), the third throttling mechanism (11), the first water valve (15), the third water valve (16), the fourth water valve (21), the second water valve (22), and the fifth water valve (23), thereby driving the coolant circuit to switch between cooling mode, heating mode, crew cabin heating battery cooling mode, dehumidification mode, external heat exchanger defrosting mode, motor heating battery mode, and motor battery heat dissipation mode.

4. The control method for the dual-flow thermal management system of an electric vehicle according to claim 3, characterized in that, When in cooling mode, the third water pump (25), the fifth water valve (23), the first shut-off valve (4) and the second shut-off valve (10) are turned off, and the first throttling mechanism (5), the second throttling mechanism (7), the third throttling mechanism (11), the first water pump (17), the second water pump (27) and the third water pump (25) are turned on. The 151 and 154 ends of the first water valve (15) are connected, and the 152 and 153 ends are connected. The 221 and 224 ends of the second water valve (22) are connected, and the 222 and 223 ends are connected. The 161 and 164 ends of the third water valve (16) are connected, and the 162 and 163 ends are connected. The 211 and 213 ends of the fourth water valve (21) are connected to cool the power battery (13) and / or the drive motor (18). Alternatively, when in motor battery cooling mode, the refrigerant circuit, the fifth water valve (23) and the third water pump (25) are closed, and the first water pump (17) and the second water pump (27) are turned on. The 153 and 154 ends of the first water valve (15) are connected, the 222 and 223 ends of the second water valve (22) are connected, the 161 and 162 ends of the third water valve (16) are connected, the 163 and 164 ends are connected, and the 211 and 213 ends of the fourth water valve (21) are connected to cool the power battery (13). Alternatively, when in the crew cabin heating battery cooling mode, close the one-way valve (9) and the third throttling mechanism (11), and turn on the first water pump (17), the second water pump (27), the third water pump (25), the first throttling mechanism (5), the second throttling mechanism (7), the first shut-off valve (4), and the second shut-off valve (10). The 151 and 154 ends of the first water valve (15) are connected, and the 152 and 153 ends are connected. The 221 and 224 ends of the second water valve (22) are connected, and the 222 and 223 ends are connected. The 161 and 164 ends of the third water valve (16) are connected, and the 162 and 163 ends are connected. The 211 and 213 ends of the fourth water valve (21) are connected. Therefore, the 231 and 232 ends of the fifth water valve (23) are connected.

5. The control method for the dual-flow thermal management system of an electric vehicle according to claim 3, characterized in that, When in dehumidification mode, the first shut-off valve (4) and the second shut-off valve (10) are closed, and the one-way valve (9), the first water pump (17), the second water pump (27), the third water pump (25), the first throttling mechanism (5), the second throttling mechanism (7), and the third throttling mechanism (11) are opened. The 151 and 152 ends of the first water valve (15) are connected, the 221 and 222 ends of the second water valve (22) are connected, the 223 and 224 ends of the second water valve (22) are connected, the 162 and 163 ends of the third water valve (16) are connected, the 212 and 213 ends of the fourth water valve (21) are connected, and the 231, 232, and 233 ends of the fifth water valve (23) are all open. Alternatively, when in the defrosting mode of the external heat exchanger, the third throttling mechanism (11), the first shut-off valve (4) and the second shut-off valve (10) are closed, and the one-way valve (9), the second throttling mechanism (7), the first water pump (17), the second water pump (27) and the third water pump (25) are opened. The 151 and 154 ends of the first water valve (15) are connected, and the 152 and 153 ends are connected. The 221 and 224 ends of the second water valve (22) are connected, and the 222 and 223 ends are connected. The 161 and 164 ends of the third water valve (16) are connected, and the 162 and 163 ends are connected. The 211 and 213 ends of the fourth water valve (21) are connected. The 231, 232 and 233 ends of the fifth water valve (23) are all open.

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