Fuel cell vehicle thermal management system and control method thereof

Abstract

The invention discloses a fuel cell vehicle thermal management system and a control method thereof. The system comprises a heat pump system, the heat pump system can independently achieve refrigeration and heating of a vehicle air conditioner, and heat carried by compressed air can be obtained from a fuel cell air supply system through a first heat exchanger or heat carried by cooling water can be obtained from a fuel cell cooling system through a second heat exchanger. And vehicle air conditioner heating is achieved. The heat pump system of the air conditioner is coupled with the fuel cell air supply system through the first heat exchanger, and the heat pump system of the air conditioner is coupled with the fuel cell cooling system through the second heat exchanger, so that dual heating by using the heat pump system and cold waste heat in compressed air can be realized, and the fuel cell device is quickly cold-started; the heat pump system can realize utilization of heat energy of compressed air and waste heat of a water circulation loop after shutdown, improves the performance coefficient of the air conditioner, reduces the energy consumption of the whole vehicle, and further improves the endurance mileage of the whole vehicle.

Description

Technical Field

[0001] The present invention relates to the field of thermal management technology, and in particular to a thermal management system for a fuel cell vehicle and a control method thereof. Background Art

[0002] The fuel cell air supply system generates a lot of heat after being compressed by the air compressor. While ensuring the required intake temperature of the fuel cell stack, the excess heat is taken away by the cooling water of the thermal management system, resulting in waste heat. The existing technology lacks research on the utilization of waste heat and cannot fully utilize the waste heat. In addition, the cold start of the fuel cell stack device mostly uses water circulation for separate heating, and the cold start warm-up process is slow. Summary of the invention

[0003] The problem to be solved by the present invention is to overcome the defects of the prior art and provide a fuel cell vehicle thermal management system and a control method thereof, which can realize the rapid warm-up process of the fuel cell device when cold started; at the same time, it can realize the utilization of compressed air thermal energy and waste heat of the water circulation loop after shutdown, improve the performance coefficient of the heat pump air conditioner, reduce the energy consumption of the whole vehicle, and thus increase the cruising range of the whole vehicle.

[0004] In order to solve the above technical problems, on the one hand, the present invention provides a fuel cell vehicle thermal management system, including a heat pump system, which can independently realize vehicle air conditioning cooling and heating, and can also obtain heat carried by compressed air from the fuel cell air supply system through a first heat exchanger or obtain heat carried by cooling water from the fuel cell cooling system through a second heat exchanger to realize vehicle air conditioning heating.

[0005] As an improvement of the thermal management system of a fuel cell vehicle of the present invention, the heat pump system includes a compressor, an in-vehicle condenser, an evaporator, the first heat exchanger, an outdoor heat exchanger and the second heat exchanger; the compressor is used to drive the refrigerant to flow to form a circulation loop; the in-vehicle condenser is used to achieve vehicle air conditioning heating; the evaporator is used to achieve vehicle air conditioning cooling; one side of the first heat exchanger is connected to the pipeline of the heat pump system, and the other side is connected to the pipeline of the fuel cell air supply system; the outdoor heat exchanger is used to exchange heat with the air; one side of the second heat exchanger is connected to the pipeline of the heat pump system, and the other side is connected to the pipeline of the fuel cell cooling system. Preferably, the heat pump system also includes a connecting pipeline and a valve to achieve its function.

[0006] Furthermore, the outlet of the compressor is connected to the in-vehicle condenser, the port a of the first heat exchanger, the outdoor heat exchanger and the inlet of the compressor respectively; a fourth stop valve is provided on the connecting pipeline between the outlet of the compressor and the in-vehicle condenser; a first stop valve, a second stop valve and a third stop valve are sequentially provided on the connecting pipeline between the outlet of the compressor and the port a of the first heat exchanger, the first stop valve is connected to the outlet of the compressor, and the connecting pipeline between the second stop valve and the third stop valve is connected to the inlet of the compressor; the first stop valve is provided on the connecting pipeline between the outlet of the compressor and the outdoor heat exchanger; the outlet of the compressor and the inlet A fifth stop valve and a sixth stop valve are arranged on the connecting pipeline between the in-vehicle condenser and the b port of the first heat exchanger, and a second electronic expansion valve is arranged on the connecting pipeline; the connecting pipeline between the second electronic expansion valve and the in-vehicle condenser is respectively connected with the evaporator, the a port of the first heat exchanger and the b port of the second heat exchanger, and the first electronic expansion valve, the first full-pass throttle valve and the second full-pass throttle valve are respectively arranged on the corresponding connecting pipelines; the evaporator is connected with the inlet of the compressor; the a port of the second heat exchanger is connected with the connecting pipeline between the fifth stop valve and the sixth stop valve; the a port of the first heat exchanger is connected with the inlet of the compressor.

[0007] Furthermore, the heat pump system further includes a pressure sensor, a first temperature sensor and a pressure-temperature sensor, wherein the pressure sensor is arranged at the inlet of the compressor; the first temperature sensor is arranged at the outlet of the compressor; and the pressure-temperature sensor is arranged on the connecting pipe between the second electronic expansion valve and the in-vehicle condenser. The first temperature sensor, the pressure sensor and the pressure-temperature sensor are used to monitor the inlet pressure and outlet temperature of the compressor, as well as the temperature and pressure in the heat pump circuit, to ensure the stable and efficient operation of the heat pump system, and to timely discover and solve problems.

[0008] Furthermore, the heat pump system also includes a gas-liquid separation tank and an air-conditioning blower. The gas-liquid separation tank is arranged at the inlet of the compressor; the air-conditioning blower can blow air to the evaporator and the in-vehicle condenser, and finally blow it into the passenger compartment.

[0009] Furthermore, the heat pump system also includes an electronic fan, which is used to blow air to the outdoor heat exchanger to improve heat dissipation efficiency.

[0010] As another improvement of the thermal management system of a fuel cell vehicle of the present invention, the fuel cell air supply system is used to provide air to the fuel cell stack, and includes an air compressor, a first heat exchanger, an intercooler and a humidifier; the air compressor is used to provide compressed air, one side of the first heat exchanger is connected to the pipeline of the heat pump system, and the other side is connected to the pipeline of the fuel cell air supply system; the intercooler is used to cool the gas flowing through, one side is connected to the pipeline of the fuel cell air supply system, and the other side is connected to the pipeline of the fuel cell cooling system; the humidifier is used to increase the moisture content of the gas flowing through.

[0011] Furthermore, the fuel cell air supply system also includes an air filter arranged at the air inlet of the air compressor.

[0012] Furthermore, the air outlet of the air compressor is connected to the c port of the first heat exchanger, the d port of the first heat exchanger is connected to the a port of the intercooler, the b port of the intercooler is connected to the humidifier, and the humidifier is connected to the air inlet of the fuel cell stack.

[0013] Furthermore, the fuel cell air supply system further includes a second temperature sensor, which is used to detect the air temperature at the intercooler port b. The second temperature sensor monitors the temperature of the airflow cooled by the intercooler, and timely adjusts the cooling efficiency of the intercooler to ensure a suitable intake air temperature.

[0014] As another improvement of the thermal management system of a fuel cell vehicle of the present invention, the fuel cell cooling system is used to cool the fuel cell stack, and includes a circulating pump, a second heat exchanger, a fuel cell stack radiator and an intercooler; the circulating pump is used to drive the flow of coolant; one side of the second heat exchanger is connected to the pipeline of the heat pump system, and the other side is connected to the pipeline of the fuel cell cooling system; the fuel cell stack radiator is used to dissipate heat for the coolant flowing through; the intercooler is used to cool the gas flowing through, one side is connected to the pipeline of the fuel cell air supply system, and the other side is connected to the pipeline of the fuel cell cooling system.

[0015] Furthermore, the fuel cell cooling system also includes a three-way proportional valve; the outlet of the circulation pump is connected to the d port of the intercooler, the c port of the intercooler is connected to the d port of the second heat exchanger, the c port of the second heat exchanger is connected to the battery stack radiator and the b port of the three-way proportional valve respectively, the battery stack radiator is connected to the c port of the three-way proportional valve, and the a port of the three-way proportional valve is connected to the circulation pump; the coolant between the inlet of the circulation pump and the d port of the intercooler flows through the battery stack, and can absorb and take away the heat generated by the operation of the battery stack.

[0016] Furthermore, the fuel cell cooling system also includes a third temperature sensor, and the third temperature sensor is used to detect the coolant temperature at the outlet of the circulation pump.

[0017] Furthermore, the fuel cell cooling system also includes an electronic fan, which is used to blow air to the stack radiator to improve heat dissipation efficiency.

[0018] In order to solve the above technical problems, the present invention provides, on the other hand, a control method of the above fuel cell vehicle thermal management system, comprising:

[0019] When the fuel cell needs to be quickly heated up after cold start, the second stop valve and the fifth stop valve are opened, the first full-pass throttle valve is in throttling mode, the second full-pass throttle valve is in full-open mode, the compressor is running, the electronic fan is running, and the port a and port b of the three-way proportional valve are connected. Other valves are in a closed state, that is, the first stop valve, the third stop valve, the fourth stop valve, the sixth stop valve, the first electronic expansion valve, and the second electronic expansion valve are all closed.

[0020] The refrigerant circulation loop is: compressor - a and b ports of the second heat exchanger - second full-pass throttle valve - first full-pass throttle valve - outdoor heat exchanger - gas-liquid separation tank - compressor. The refrigerant releases heat when flowing through the second heat exchanger and absorbs heat when flowing through the outdoor heat exchanger, heating the coolant of the fuel cell cooling system. At the same time, the fuel cell cooling system and the fuel cell air supply system are also in working condition. The a and b ports of the three-way proportional valve are connected. The circulation loop of the coolant is: circulation pump - d and c ports of the intercooler - d and c ports of the second heat exchanger - circulation pump. The air after the air compressor is in a high temperature and high pressure state, so the coolant is doubly heated by the second heat exchanger and the intercooler, achieving the purpose of rapid cold start warming of the stack.

[0021] Furthermore, when the stack is shut down and the heat of the fuel cell cooling system needs to be recovered for air conditioning and heating, the fourth stop valve and the sixth stop valve are opened, the second full-pass throttle valve is turned on in throttling mode, the compressor and the air-conditioning blower are running, and the port a and port b of the three-way proportional valve are connected. The other valves are all in a closed state, that is, the first stop valve, the second stop valve, the third stop valve, the fifth stop valve, the first full-pass throttle valve, the first electronic expansion valve, and the second electronic expansion valve are all closed.

[0022] The refrigerant circulation loop is: compressor - in-vehicle condenser - second full-pass throttle valve - b and a ports of the second heat exchanger - gas-liquid separation tank - compressor. The refrigerant releases heat when it flows through the in-vehicle condenser, and recycles the waste heat of the water circulation loop when it flows through the second heat exchanger to complete the air conditioning heating cycle. At the same time, the fuel cell cooling system also works but the fuel cell air supply system does not work. The a and b ports of the three-way proportional valve are connected to slow down the heat loss rate. The coolant circulation loop is: circulation pump - d and c ports of the intercooler - d and c ports of the second heat exchanger - circulation pump, which continuously provides heat to the heat pump system through the second heat exchanger.

[0023] Furthermore, when the heat of the compressed air from the fuel cell air supply system is needed for air conditioning heating, the control is to open the third stop valve and the fourth stop valve, open the second electronic expansion valve, operate the compressor, operate the air conditioning blower, and connect the ports a and c of the three-way proportional valve. All other valves are in a closed state, that is, the first stop valve, the second stop valve, the fifth stop valve, the sixth stop valve, the first full-pass throttle valve, the second full-pass throttle valve, and the first electronic expansion valve are all closed.

[0024] The refrigerant circulation loop is: compressor - in-vehicle condenser - second electronic expansion valve - first heat exchanger - gas-liquid separation tank - compressor, which transfers the heat energy in the compressed air to the vehicle to complete air conditioning heating.

[0025] At the same time, the fuel cell cooling system and the fuel cell air supply system are also in working condition, the a port and c port of the three-way proportional valve are connected, and the circulation loop of the coolant is: circulation pump-d and c ports of the intercooler-d and c ports of the second heat exchanger-fuel stack radiator-a and c ports of the three-way proportional valve-circulation pump, completing the cooling process of the fuel stack. And during the coolant circulation process, the three-way proportional valve can be opened according to the required proportion according to the temperature feedback of the second temperature sensor and the third temperature sensor, and the electronic fan can be operated to complete the cooling process of the fuel stack.

[0026] Furthermore, when the air conditioner is required to cool alone, the control is to open the first stop valve, open the first electronic expansion valve, open the first full-throttle valve, operate the compressor, operate the air conditioner blower, and operate the electronic fan. All other valves are in a closed state, that is, the second stop valve, the third stop valve, the fourth stop valve, the fifth stop valve, the sixth stop valve, the second full-throttle valve, and the second electronic expansion valve are all closed. This process does not involve the control of the three-way proportional valve, and is in the default state of connection between port a and port c.

[0027] Furthermore, when the air conditioner is required to heat alone, the control is to open the first stop valve and the fourth stop valve, the first full-pass throttle valve is in throttling mode, the compressor, the air conditioner blower are running, and the electronic fan is running. The other valves are all in the closed state, that is, the second stop valve, the first electronic expansion valve, the third stop valve, the fifth stop valve, the sixth stop valve, the second full-pass throttle valve, and the second electronic expansion valve are all closed. This process does not involve the control of the three-way proportional valve, and is in the default state of connection between port a and port c.

[0028] Furthermore, when the cold start heating of the fuel cell and the air conditioning heating are required to be performed simultaneously, the second stop valve and the fourth stop valve are opened, the first full-pass throttle valve is in throttling mode, the compressor is running, the air conditioning blower is running, and the port a and port b of the three-way proportional valve are connected. The other valves are all in a closed state, that is, the first stop valve, the first electronic expansion valve, the third stop valve, the fifth stop valve, the sixth stop valve, the second full-pass throttle valve, and the second electronic expansion valve are all closed.

[0029] Furthermore, when the fuel cell needs to be cooled separately, the control is to connect the ports a and c of the three-way proportional valve, operate the circulating pump, and operate the electronic fan. This process does not involve the control of the first stop valve, the second stop valve, the fourth stop valve, the first electronic expansion valve, the third stop valve, the fifth stop valve, the sixth stop valve, the first full-pass throttle valve, the second full-pass throttle valve, and the second electronic expansion valve, which can all be in the default closed state.

[0030] Furthermore, when the fuel cell cooling and air conditioning refrigeration are required to be performed simultaneously, the control is such that: the first stop valve is opened, the first electronic expansion valve is opened, the first full-pass throttle valve is in full-open mode, the compressor is running, the electronic fan is running, the air conditioning blower is running, and the port a and port c of the three-way proportional valve are connected. The other valves are all in a closed state, that is, the second stop valve, the fourth stop valve, the third stop valve, the fifth stop valve, the sixth stop valve, the second full-pass throttle valve, and the second electronic expansion valve are all closed.

[0031] In summary, by adopting the above-mentioned fuel cell vehicle thermal management system and control method thereof, the heat pump system of the air conditioner is coupled with the fuel cell air supply system through the first heat exchanger, and the heat pump system of the air conditioner is coupled with the fuel cell cooling system through the second heat exchanger, thereby realizing dual heating by utilizing the heat pump system and the waste heat from the compressed air, so that the fuel cell device can be quickly cold-started. In addition, the heat pump system can simultaneously realize the utilization of the thermal energy of the compressed air and the waste heat of the water circulation loop after shutdown, thereby improving the performance coefficient of the air conditioner, reducing the energy consumption of the whole vehicle, and thereby improving the cruising range of the whole vehicle. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] In the attached picture:

[0033] Figure 1It is a schematic diagram of the structure of the thermal management system of a fuel cell vehicle of the present invention.

[0034] In the figure, 1. pressure sensor; 2. fifth stop valve; 3. first temperature sensor; 4. sixth stop valve; 5. gas-liquid separation tank; 6. compressor; 7. second stop valve; 8. first stop valve; 9. fourth stop valve; 10. second heat exchanger; 11. three-way proportional valve; 12. battery stack radiator; 13. outdoor heat exchanger; 14. electronic fan; 15. second full-pass throttle valve; 16. air conditioning blower; 17. evaporator; 18. in-vehicle condenser; 19. first full-pass throttle valve; 20. first electronic expansion valve; 21. third stop valve; 22. first heat exchanger; 23. second electronic expansion valve; 24. pressure and temperature sensor; 25. air filter; 26. air compressor; 27. intercooler; 28. second temperature sensor; 29. ​​humidifier; 30. battery stack; 31. third temperature sensor; 32. circulation pump. DETAILED DESCRIPTION

[0035] The specific embodiments of the present invention are further described below in conjunction with the accompanying drawings. It should be noted that the description of these embodiments is used to help understand the present invention, but does not constitute a limitation of the present invention.

[0036] Example 1

[0037] Figure 1 The present invention shows a fuel cell vehicle thermal management system. Figure 1 As shown, the fuel cell vehicle thermal management system includes a heat pump system, which can independently realize vehicle air conditioning cooling and heating. It can also obtain heat carried by compressed air from the fuel cell air supply system through the first heat exchanger 22 or obtain heat carried by cooling water from the fuel cell cooling system through the second heat exchanger 10 to realize vehicle air conditioning heating.

[0038] The heat pump system includes a compressor 6, an in-vehicle condenser 18, an evaporator 17, a first heat exchanger 22, an outdoor heat exchanger 13, and a second heat exchanger 10; the compressor 6 is used to drive the refrigerant to flow to form a circulation loop; the in-vehicle condenser 18 is used to achieve vehicle air conditioning heating; the evaporator 17 is used to achieve vehicle air conditioning cooling; one side of the first heat exchanger 22 is connected to the pipeline of the heat pump system, and the other side is connected to the pipeline of the fuel cell air supply system; the outdoor heat exchanger 13 is used to exchange heat with the air; one side of the second heat exchanger 10 is connected to the pipeline of the heat pump system, and the other side is connected to the pipeline of the fuel cell cooling system. Preferably, the heat pump system also includes a connecting pipeline and a valve to achieve its function.

[0039] The specific piping connection structure of the heat pump system is as follows: the outlet of the compressor 6 is connected to the in-vehicle condenser 18, the port a of the first heat exchanger 22, the outdoor heat exchanger 13 and the inlet of the compressor 6 respectively; a fourth stop valve 9 is provided on the connecting pipe between the outlet of the compressor 6 and the in-vehicle condenser 18; a first stop valve 8, a second stop valve 7 and a third stop valve 21 are provided in sequence on the connecting pipe between the outlet of the compressor 6 and the port a of the first heat exchanger 22, the first stop valve 8 is connected to the outlet of the compressor 6, and the connecting pipe between the second stop valve 7 and the third stop valve 21 is connected to the inlet of the compressor 6; a first stop valve 8 is provided on the connecting pipe between the outlet of the compressor 6 and the outdoor heat exchanger 13; the outlet of the compressor 6 and the inlet A fifth stop valve 2 and a sixth stop valve 4 are arranged on the connecting pipeline between the in-vehicle condenser 18 and the b port of the first heat exchanger 22, and a second electronic expansion valve 23 is arranged on the connecting pipeline; the connecting pipeline between the second electronic expansion valve 23 and the in-vehicle condenser 18 is respectively connected to the evaporator 17, the a port of the first heat exchanger 22 and the b port of the second heat exchanger 10, and the first electronic expansion valve 20, the first full-pass throttle valve 19 and the second full-pass throttle valve 15 are respectively arranged on the corresponding connecting pipelines; the evaporator 17 is connected to the inlet of the compressor 6; the a port of the second heat exchanger 10 is connected to the connecting pipeline between the fifth stop valve 2 and the sixth stop valve 4; the a port of the first heat exchanger 22 is connected to the inlet of the compressor 6.

[0040] The heat pump system also includes a pressure sensor 1, a first temperature sensor 3 and a pressure-temperature sensor 24. The pressure sensor 1 is arranged at the inlet of the compressor 6; the first temperature sensor 3 is arranged at the outlet of the compressor 6; the pressure-temperature sensor 24 is arranged on the connecting pipe between the second electronic expansion valve 23 and the in-vehicle condenser 18. The first temperature sensor 3, the pressure sensor 1 and the pressure-temperature sensor 24 monitor the inlet pressure and outlet temperature of the compressor 6, as well as the temperature and pressure in the heat pump circuit, to ensure the stable and efficient operation of the heat pump system, and to find and solve problems in time.

[0041] The heat pump system further includes a gas-liquid separation tank 5 and an air-conditioning blower 16 . The gas-liquid separation tank 5 is arranged at the inlet of the compressor 6 . The air-conditioning blower 16 can blow air toward the evaporator 17 and the in-vehicle condenser 18 , and finally blow air into the passenger compartment.

[0042] The heat pump system further includes an electronic fan 14, which is used to blow air toward the outdoor heat exchanger 13 to improve heat dissipation efficiency.

[0043] The fuel cell air supply system is used to provide air to the fuel cell stack 30, and includes an air compressor 26, a first heat exchanger 22, an intercooler 27 and a humidifier 29; the air compressor 26 is used to provide compressed air, one side of the first heat exchanger 22 is connected to the pipeline of the heat pump system, and the other side is connected to the pipeline of the fuel cell air supply system; the intercooler 27 is used to cool the gas flowing through, one side is connected to the pipeline of the fuel cell air supply system, and the other side is connected to the pipeline of the fuel cell cooling system; the humidifier 29 is used to increase the moisture content of the gas flowing through.

[0044] The fuel cell air supply system further includes an air filter 25 disposed at the air inlet of the air compressor 26 .

[0045] The air outlet of the air compressor 26 is connected to the c port of the first heat exchanger 22 , the d port of the first heat exchanger 22 is connected to the a port of the intercooler 27 , the b port of the intercooler 27 is connected to the humidifier 29 , and the humidifier 29 is connected to the air inlet of the fuel cell stack 30 .

[0046] The fuel cell air supply system also includes a second temperature sensor 28, which is used to detect the air temperature at the outlet of the intercooler 27b. The second temperature sensor 28 monitors the temperature of the air flow cooled by the intercooler 27, and timely adjusts the cooling efficiency of the intercooler 27 to ensure a suitable intake air temperature.

[0047] The fuel cell cooling system is used to cool the stack 30, and includes a circulating pump 32, a second heat exchanger 10, a stack radiator 12, and an intercooler 27; the circulating pump 32 is used to drive the coolant to flow; one side of the second heat exchanger 10 is connected to the pipeline of the heat pump system, and the other side is connected to the pipeline of the fuel cell cooling system; the stack radiator 12 is used to dissipate heat from the coolant flowing through; the intercooler 27 is used to cool the gas flowing through, and one side is connected to the pipeline of the fuel cell air supply system, and the other side is connected to the pipeline of the fuel cell cooling system. The coolant is usually water.

[0048] The fuel cell cooling system also includes a three-way proportional valve 11; the outlet of the circulation pump 32 is connected to the d port of the intercooler 27, the c port of the intercooler 27 is connected to the d port of the second heat exchanger 10, the c port of the second heat exchanger 10 is connected to the stack radiator 12 and the b port of the three-way proportional valve 11 respectively, the stack radiator 12 is connected to the c port of the three-way proportional valve 11, and the a port of the three-way proportional valve 11 is connected to the circulation pump 32; the coolant between the inlet of the circulation pump 32 and the d port of the intercooler 27 flows through the stack 30, which can absorb and take away the heat generated by the operation of the stack 30.

[0049] The fuel cell cooling system further includes a third temperature sensor 31 , which is used to detect the temperature of the coolant at the outlet of the circulation pump 32 .

[0050] The fuel cell cooling system also includes an electronic fan 14, which is used to blow air toward the stack radiator 12 to improve the heat dissipation efficiency.

[0051] Example 2

[0052] The control method of the above-mentioned fuel cell vehicle thermal management system of the present invention can have eight working modes through control: air conditioning cooling alone, air conditioning heating alone, shutdown waste heat recovery heating mode, fuel cell cold start heating mode, fuel cell cold start heating and air conditioning heating mode, fuel cell cooling mode, fuel cell cooling and air conditioning cooling mode and fuel cell cooling and air conditioning heating mode, which are described in detail as follows. Among them, each stop valve, electronic expansion valve and full-pass throttle valve are closed by default, and the three-way proportional valve 11 is connected to the ac port by default. In the subsequent description, only the components that need to be opened and the status of the three-way proportional valve 11 are described.

[0053] Mode 1: Air conditioning alone. The heat pump system independently realizes vehicle air conditioning cooling, and does not exchange heat with the fuel cell air supply system and fuel cell cooling system.

[0054] The specific working control process is: the first stop valve 8 is opened, the first electronic expansion valve 20 is opened, the first full-pass throttle valve 19 is in full-open mode, and the compressor 6, the air-conditioning blower 16 and the electronic fan 14 are running. The refrigerant circulation loop is: compressor 6-outdoor heat exchanger 13-first full-pass throttle valve 19-first electronic expansion valve 20-evaporator 17-gas-liquid separation tank 5-compressor 6. When the refrigerant flows through the outdoor heat exchanger 13, it dissipates heat to the atmosphere, and when it flows through the evaporator 17, it absorbs heat, cooperates with the air-conditioning blower 16 to blow cold air into the passenger compartment, and completes the air-conditioning independent cooling.

[0055] Mode 2: Air conditioning heating alone. The heat pump system independently realizes vehicle air conditioning heating, and does not exchange heat with the fuel cell air supply system and fuel cell cooling system.

[0056] The specific working control process is: the first stop valve 8 and the fourth stop valve 9 are open, the first full-pass throttle valve 19 is in throttling mode, and the compressor 6, the air conditioning blower 16 and the electronic fan 14 are running. The refrigerant circulation loop is: compressor 6-in-vehicle condenser 18-first full-pass throttle valve 19-outdoor heat exchanger 13-gas-liquid separation tank 5-compressor 6. The refrigerant releases heat when flowing through the in-vehicle condenser 18, cooperates with the air conditioning blower 16 to blow hot air into the passenger compartment, and absorbs heat when flowing through the outdoor heat exchanger 13. The electronic fan 14 can improve the heat absorption efficiency, thereby transferring the heat energy in the outdoor air to the vehicle, and completing the air conditioning heating alone.

[0057] Mode 3: Shutdown waste heat recovery heating mode. The heat pump system is used to recover the waste heat from the fuel cell cooling system circuit after shutdown.

[0058] At this time, the fuel cell stack 30 is shut down, and the water circulation loop contains a large amount of heat energy, which can be recovered for air conditioning and heating. That is, the heat carried by the cooling water is obtained from the fuel cell cooling system through the second heat exchanger 10 to achieve vehicle air conditioning and heating.

[0059] The specific working control process is: the fourth stop valve 9 and the sixth stop valve 4 are opened, the second full-pass throttle valve 15 is turned on the throttling mode, and the compressor 6 and the air-conditioning blower 16 are running. The refrigerant circulation loop is: compressor 6-in-vehicle condenser 18-second full-pass throttle valve 15-b and a ports of the second heat exchanger 10-gas-liquid separation tank 5-compressor 6. The refrigerant releases heat when flowing through the in-vehicle condenser 18, and recycles the waste heat of the water circulation loop when flowing through the second heat exchanger 10 to complete the air conditioning heating cycle. At the same time, the fuel cell cooling system also works but the fuel cell air supply system does not work. The a port and the b port of the three-way proportional valve 11 are connected to slow down the heat loss rate. The circulation loop of the coolant is: circulation pump 32-d and c ports of the intercooler 27-d and c ports of the second heat exchanger 10-circulation pump 32, and continuously provides heat to the heat pump system through the second heat exchanger 10.

[0060] In addition, a temperature value T can be set 0 , only when the coolant temperature at the outlet of the circulating pump 32 is higher than T 0 When the detection value of the third temperature sensor 31 is greater than T 0 This mode can only be enabled when

[0061] Mode 4: Fuel cell cold start heating mode. Through dual heating of the heat pump system and the heat in the compressed air, the fuel cell device can be quickly cold started.

[0062] Fuel cell cold start heating is an important method to solve the difficulty of fuel cell starting in low temperature environment. Under low temperature conditions, water vapor inside the fuel cell is easy to freeze, resulting in blockage of the catalyst layer and diffusion layer, hindering the reaction, thereby reducing the performance of the fuel cell or even making it impossible to start. Therefore, heating to increase the temperature of the fuel cell and accelerate the reaction rate is a key link in the cold start process of the fuel cell.

[0063] The specific working control process is: the second stop valve 7 and the fifth stop valve 2 are open, the first full-pass throttle valve 19 is in the throttling mode, the second full-pass throttle valve 15 is in the full-open mode, the compressor 6 is running, and the electronic fan 14 is running. The refrigerant circulation loop is: compressor 6-port a and b of the second heat exchanger 10-second full-pass throttle valve 15-first full-pass throttle valve 19-outdoor heat exchanger 13-gas-liquid separation tank 5-compressor 6. The refrigerant releases heat when flowing through the second heat exchanger 10 and absorbs heat when flowing through the outdoor heat exchanger 13, heating the coolant of the fuel cell cooling system.

[0064] At the same time, the fuel cell cooling system and the fuel cell air supply system are also in working condition, the a port and the b port of the three-way proportional valve 11 are connected, and the circulation loop of the coolant is: circulating pump 32-d and c ports of the intercooler 27-d and c ports of the second heat exchanger 10-circulating pump 32. The air after the air compressor 26 is in a high temperature and high pressure state, so that the coolant is doubly heated by the second heat exchanger 10 and the intercooler 27, so as to achieve the purpose of rapid cold start and warm-up of the fuel cell stack 30.

[0065] Mode 5: Fuel cell cold start heating and air conditioning heating are performed simultaneously. The heat in the compressed air is used to heat the fuel cell device to achieve rapid cold start.

[0066] The specific working control process is: the second stop valve 7 and the fourth stop valve 9 are open, the first full-pass throttle valve 19 is in throttling mode, the compressor 6 is running, and the air-conditioning blower 16 is running. The refrigerant circulation loop is: compressor 6-in-vehicle condenser 18-first full-pass throttle valve 19-outdoor heat exchanger 13-gas-liquid separation tank 5-compressor 6, completing air-conditioning heating.

[0067] At the same time, the fuel cell cooling system and the fuel cell air supply system are also in working condition, the a port and the b port of the proportional valve 11 are connected, and the circulation loop of the coolant is: circulating pump 32-d and c ports of the intercooler 27-d and c ports of the second heat exchanger 10-a and b ports of the three-way proportional valve 11-circulating pump 32.

[0068] In this mode, the air behind the air compressor 26 is in a high temperature and high pressure state, and the heat is transferred to the water circulation loop through the intercooler 27 to complete the stack heating process. However, the heat pump system needs to heat the passenger compartment, so it does not provide heat to the fuel cell cooling system through the second heat exchanger 10 for fuel cell cold start heating.

[0069] Mode 6: Fuel cell cooling mode. Only the fuel cell cooling system works, the three-way proportional valve 11a and c ports are connected, the circulating pump 32 and the electronic fan 14 are running, and the circulation loop of the coolant is: circulating pump 32-d and c ports of the intercooler 27-d and c ports of the second heat exchanger 10-fuel cell radiator 12-a and c ports of the three-way proportional valve 11-circulating pump 32, completing the cooling process of the fuel cell alone.

[0070] Mode 7: Fuel cell cooling and air conditioning refrigeration mode.

[0071] The specific working control process is: the first stop valve 8 is opened, the first electronic expansion valve 20 is opened, the first full-pass throttle valve 19 is in full-open mode, and the compressor 6, the electronic fan 14 and the air-conditioning blower 16 are running. The refrigerant circulation loop is: compressor 6-outdoor heat exchanger 13-first full-pass throttle valve 19-first electronic expansion valve 20-evaporator 17-gas-liquid separation tank 5-compressor 6. The refrigerant releases heat when flowing through the outdoor heat exchanger 13 and absorbs heat when flowing through the evaporator 17, and cooperates with the air-conditioning blower 16 to complete the air-conditioning refrigeration cycle.

[0072] At the same time, the fuel cell cooling system and the fuel cell air supply system are also in working condition, the three-way proportional valve 11a-c are connected, and the circulation loop of the coolant is: circulation pump 32-d and c ports of the intercooler 27-d and c ports of the second heat exchanger 10-fuel cell stack radiator 12-a and c ports of the three-way proportional valve 11-circulation pump 32. The coolant releases heat at the fuel cell stack radiator 12 and absorbs heat when flowing through the fuel cell stack 30 and the intercooler 27, completing the cooling process of the fuel cell stack.

[0073] Mode 8: Fuel cell cooling and air conditioning heating mode. The heat pump system obtains the heat carried by the compressed air from the fuel cell air supply system through the first heat exchanger 22 to achieve vehicle air conditioning heating.

[0074] The specific work control process is: the third stop valve 21 and the fourth stop valve 9 are opened, the second electronic expansion valve 23 is turned on, the compressor 6 and the air-conditioning blower 16 are running, and the refrigerant circulation loop is: compressor 6-in-vehicle condenser 18-second electronic expansion valve 23-first heat exchanger 22-gas-liquid separation tank 5-compressor 6, transferring the heat energy in the compressed air to the vehicle to complete air-conditioning heating.

[0075] At the same time, the fuel cell cooling system and the fuel cell air supply system are also in working condition, the three-way proportional valve 11a-c are connected, and the circulation loop of the coolant is: circulation pump 32-d and c ports of the intercooler 27-d and c ports of the second heat exchanger 10-fuel cell radiator 12-a and c ports of the three-way proportional valve 11-circulation pump 32, completing the cooling process of the fuel cell stack.

[0076] In addition, in this mode, it is necessary to monitor the feedback temperature of the second temperature sensor 28 to ensure that the intake temperature of the stack 30 is normal. If necessary, the air conditioning heating efficiency can be reduced. In addition, during the coolant circulation process, since the cooling capacity of the intercooler 27 for compressed air is required to be reduced, the cooling capacity of the fuel cell cooling system may be redundant. According to the temperature feedback of the second temperature sensor 28 and the third temperature sensor 31, the three-way proportional valve 11 can be controlled to open at the required ratio, and the electronic fan 14 can be operated to complete the normal cooling of the stack 30.

[0077] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit its protection scope. Although the present invention has been described in detail with reference to the above embodiments, ordinary technicians in the field should understand that after reading the present invention, those skilled in the art can still make various changes, modifications or equivalent substitutions to the specific implementation methods of the invention, but these changes, modifications or equivalent substitutions are all within the protection scope of the pending claims of the invention.

Claims

1. A fuel cell vehicle thermal management system, characterized in that: The invention comprises a heat pump system, which can independently realize vehicle air conditioning cooling and heating, and can also obtain heat carried by compressed air from a fuel cell air supply system through a first heat exchanger (22) or obtain heat carried by cooling water from a fuel cell cooling system through a second heat exchanger (10), thereby realizing vehicle air conditioning heating.

2. A fuel cell vehicle thermal management system according to claim 1, characterized in that: The heat pump system comprises a compressor (6), an in-vehicle condenser (18), an evaporator (17), the first heat exchanger (22), an outdoor heat exchanger (13) and the second heat exchanger (10); the compressor (6) is used to drive the refrigerant to flow to form a circulation loop; the in-vehicle condenser (18) is used to achieve vehicle air conditioning heating; the evaporator (17) is used to achieve vehicle air conditioning cooling; one side of the first heat exchanger (22) is connected to the pipeline of the heat pump system, and the other side is connected to the pipeline of the fuel cell air supply system; the outdoor heat exchanger (13) is used to exchange heat with air; one side of the second heat exchanger (10) is connected to the pipeline of the heat pump system, and the other side is connected to the pipeline of the fuel cell cooling system.

3. A fuel cell vehicle thermal management system according to claim 2, characterized in that: The outlet of the compressor (6) is respectively connected to the in-vehicle condenser (18), the port a of the first heat exchanger (22), the outdoor heat exchanger (13) and the inlet of the compressor (6); A fourth stop valve (9) is provided on the connecting pipeline between the outlet of the compressor (6) and the in-vehicle condenser (18); A first stop valve (8), a second stop valve (7) and a third stop valve (21) are sequentially arranged on a communication pipeline between the outlet of the compressor (6) and the port a of the first heat exchanger (22); the first stop valve (8) is communicated with the outlet of the compressor (6); and a communication pipeline between the second stop valve (7) and the third stop valve (21) is communicated with the inlet of the compressor (6); The first stop valve (8) is provided on the communication pipeline between the outlet of the compressor (6) and the outdoor heat exchanger (13); A fifth stop valve (2) and a sixth stop valve (4) are provided on the connecting pipeline between the outlet and the inlet of the compressor (6); The in-vehicle condenser (18) is connected to the port b of the first heat exchanger (22), and a second electronic expansion valve (23) is provided on the connecting pipeline; The communication pipeline between the second electronic expansion valve (23) and the in-vehicle condenser (18) is respectively connected to the evaporator (17), the port a of the first heat exchanger (22) and the port b of the second heat exchanger (10), and the corresponding communication pipelines are respectively provided with the first electronic expansion valve (20), the first full-pass throttle valve (19) and the second full-pass throttle valve (15); The evaporator (17) is in communication with the inlet of the compressor (6); The port a of the second heat exchanger (10) is in communication with the connecting pipeline between the fifth stop valve (2) and the sixth stop valve (4); The port a of the first heat exchanger (22) is connected to the inlet of the compressor (6).

4. A fuel cell vehicle thermal management system according to claim 2, characterized in that: The heat pump system further comprises a gas-liquid separation tank (5) and an air-conditioning blower (16), wherein the gas-liquid separation tank (5) is arranged at the inlet of the compressor (6); the air-conditioning blower (16) is capable of blowing air toward the evaporator (17) and the in-vehicle condenser (18), and finally blowing air into the passenger compartment.

5. A fuel cell vehicle thermal management system according to claim 2, characterized in that: The heat pump system further comprises an electronic fan (14), wherein the electronic fan (14) is used to blow air toward the outdoor heat exchanger (13) to improve heat dissipation efficiency.

6. A fuel cell vehicle thermal management system according to claim 1, characterized in that: The fuel cell air supply system is used to provide air to the fuel cell stack (30), and comprises an air compressor (26), a first heat exchanger (22), an intercooler (27) and a humidifier (29); The air compressor (26) is used to provide compressed air; one side of the first heat exchanger (22) is connected to the pipeline of the heat pump system, and the other side is connected to the pipeline of the fuel cell air supply system; the intercooler (27) is used to cool the gas flowing through, one side is connected to the pipeline of the fuel cell air supply system, and the other side is connected to the pipeline of the fuel cell cooling system; the humidifier (29) is used to increase the moisture content of the gas flowing through.

7. A fuel cell vehicle thermal management system according to claim 6, characterized in that: The air outlet of the air compressor (26) is connected to the c port of the first heat exchanger (22), the d port of the first heat exchanger (22) is connected to the a port of the intercooler (27), the b port of the intercooler (27) is connected to the humidifier (29), and the humidifier (29) is connected to the air inlet of the fuel cell stack (30).

8. A fuel cell vehicle thermal management system according to claim 1, characterized in that: The fuel cell cooling system is used to cool the fuel cell stack (30), and comprises a circulation pump (32), a second heat exchanger (10), a fuel cell stack radiator (12) and an intercooler (27); The circulation pump (32) is used to drive the coolant to flow; one side of the second heat exchanger (10) is connected to the pipeline of the heat pump system, and the other side is connected to the pipeline of the fuel cell cooling system; the stack radiator (12) is used to dissipate heat from the coolant flowing through; the intercooler (27) is used to cool the gas flowing through, one side of the intercooler is connected to the pipeline of the fuel cell air supply system, and the other side is connected to the pipeline of the fuel cell cooling system.

9. A fuel cell vehicle thermal management system according to claim 8, characterized in that: The fuel cell cooling system further comprises a three-way proportional valve (11); the outlet of the circulation pump (32) is connected to the port d of the intercooler (27); the port c of the intercooler (27) is connected to the port d of the second heat exchanger (10); the port c of the second heat exchanger (10) is connected to the stack radiator (12) and the port b of the three-way proportional valve (11) respectively; the stack radiator (12) is connected to the port c of the three-way proportional valve (11); and the port a of the three-way proportional valve (11) is connected to the circulation pump (32); The coolant between the inlet of the circulation pump (32) and the port d of the intercooler (27) flows through the battery stack (30), and can absorb and take away the heat generated by the operation of the battery stack (30).

10. A control method for a fuel cell vehicle thermal management system according to any one of claims 1 to 9, characterized in that: include: When the fuel cell needs to be quickly heated up after cold start, the control is performed so that: the second stop valve (7) and the fifth stop valve (2) are opened, the first full-pass throttle valve (19) is in the throttling mode, the second full-pass throttle valve (15) is in the fully open mode, the compressor (6) is running, the electronic fan (14) is running, and the a port and the b port of the three-way proportional valve 11 are connected.

11. A fuel cell vehicle thermal management system according to claim 10, characterized in that: When the fuel cell stack (30) is shut down and the heat of the fuel cell cooling system needs to be recovered for air conditioning and heating, the fourth stop valve (9) and the sixth stop valve (4) are controlled to be open, the second full-pass throttle valve (15) is turned on in throttling mode, the compressor (6) and the air conditioning blower (16) are running, and the a port and the b port of the three-way proportional valve 11 are connected.

12. A fuel cell vehicle thermal management system according to claim 10, characterized in that: When it is necessary to utilize the heat of compressed air from the fuel cell air supply system for air conditioning and heating, the control is performed so that: the third stop valve (21) and the fourth stop valve (9) are opened, the second electronic expansion valve (23) is turned on, the compressor (6) and the air conditioning blower (16) are operated, and the ports a and c of the three-way proportional valve (11) are connected.

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