Thermal management system of hydrogen fuel cell hybrid power vehicle and working mode of thermal management system

Abstract

The invention relates to a thermal management system of a hydrogen fuel cell hybrid power vehicle. The thermal management system comprises a fuel cell cooling system and a fuel cell thermal utilization system. The fuel cell cooling system is connected with the fuel cell heat utilization system through a heat exchanger; the turbine power generation unit is used for generating electric energy by using heat of the fuel cell cooling system; and the warm air units are arranged in the driver cabin and the passenger cabin and are used for heating by utilizing the heat of the fuel cell cooling system. The fuel cell cooling system and the fuel cell heat utilization system are connected through the heat exchanger, the warm air unit and the turbine power generation unit are arranged in the fuel cell heat utilization system, different working modes are selected according to different working environments, when heating is needed, waste heat of the fuel cell system is fully utilized for heating, and the energy consumption is reduced. When heating is not needed, waste heat is converted into electric energy to be stored through the turbine generator, and the energy efficiency of the fuel cell system is effectively improved.

Description

Technical Field

[0001] The present invention relates to the technical field of fuel cells, and in particular to a thermal management system for a hydrogen fuel cell hybrid vehicle and its operating mode. Background Art

[0002] Hydrogen fuel cells are energy conversion devices that use the chemical energy of hydrogen and oxygen in the air to generate electricity. Their high power generation efficiency and minimal environmental pollution have led to their widespread use in the automotive sector. However, hydrogen fuel cells currently generate a significant amount of waste heat during operation. This heat is typically dissipated through air cooling systems. This is particularly true for buses and coaches, as the fuel cells used in these systems are relatively powerful and generate significant amounts of excess heat. This waste heat not only consumes electricity but also results in low energy efficiency for hydrogen fuel cells. To maintain the appropriate operating temperature for each fuel cell system, nearly 50% of the energy is converted into heat. This heat is removed through heat exchange with the coolant and then dissipated to the atmosphere through a radiator system.

[0003] In the prior art, waste heat from a fuel cell system has been used to achieve in-vehicle heating. However, in the summer when heating is not required, the waste heat from the fuel cell system cannot be effectively utilized, resulting in low energy efficiency.

[0004] In addition, in the cold winter, the ambient temperature is extremely low, and hydrogen fuel cells also have the problem of long low-temperature startup time.

[0005] Therefore, it is urgent to design a hydrogen fuel cell hybrid vehicle thermal management system and its working mode to solve the problems existing in the above-mentioned prior art. Summary of the Invention

[0006] In view of this, the present invention provides a hydrogen fuel cell hybrid vehicle thermal management system and its operating mode, the purpose of which is to rationally utilize the waste heat generated by the hydrogen fuel cell during operation, while reducing the power required for the fuel cell cooling equipment to dissipate heat, thereby improving the energy utilization efficiency of the hydrogen fuel cell system.

[0007] To achieve the above object, the present invention adopts the following technical solutions:

[0008] A thermal management system for a hydrogen fuel cell hybrid vehicle, the thermal management system comprising a fuel cell cooling system and a fuel cell heat utilization system;

[0009] The fuel cell heat utilization system includes a first outlet of a heat exchanger, a warm air gas-liquid heater, a first three-way valve, a turbine power generation unit, a warm air unit, a second three-way valve, a warm air water pump, and a first inlet of the heat exchanger, which are connected in sequence; the fluid medium in the fuel cell heat utilization system is a phase change material;

[0010] The fuel cell cooling system and the fuel cell heat utilization system are connected via a heat exchanger;

[0011] The turbine power generation unit is used to generate electricity using the heat of the fuel cell cooling system; the heater unit is arranged in the driver's cabin and the passenger cabin and is used to provide heating using the heat of the fuel cell cooling system.

[0012] Furthermore, the fuel cell cooling system includes a system expansion water tank, a system water pump, a thermostat, a system PTC, and a system radiator; the cooling path outlet of the fuel cell stack is connected to the system water pump, the second inlet of the heat exchanger, the second outlet of the heat exchanger, and the A inlet of the thermostat in sequence, the B outlet of the thermostat is connected to the system radiator, and the C outlet of the thermostat is connected to the system PTC. The system radiator and the system PTC are both connected to the cooling path inlet of the fuel cell stack; a system expansion water tank for replenishing the fuel cell coolant is also provided between the cooling path outlet of the fuel cell stack and the system water pump.

[0013] Furthermore, the first outlet of the heat exchanger is connected to the warm air gas-liquid heater, the A inlet of the first three-way valve, the B outlet of the first three-way valve is connected to the turbine power generation unit and the warm air unit in sequence, and then connected to the A inlet of the second three-way valve; the C outlet of the first three-way valve is connected to the C inlet of the second three-way valve; the B outlet of the second three-way valve is connected to the warm air water pump and the first inlet of the heat exchanger in sequence.

[0014] Furthermore, the turbine power generation unit includes a gas-liquid separation device, a turbine generator, a turbine power generation controller, a recycling device and a bypass valve. The inlet of the turbine power generation unit is a T-branch structure, the B outlet of the first three-way valve is connected to the inlet of the T-branch structure, the first outlet of the T-branch structure is connected to the bypass valve, and the second outlet of the T-branch structure is connected to the gas-liquid separation device; the gas outlet of the gas-liquid separation device is connected to the gas inlet of the turbine generator, the gas outlet of the turbine generator is connected to the inlet of the recycling device, the outlet of the recycling device, the liquid outlet of the gas-liquid separation device and the outlet of the bypass valve are connected to the inlet of the warm air unit, and the turbine generator is electrically connected to the turbine power generation controller.

[0015] Furthermore, the heating unit is a structure in which a heating bypass valve, a first heating device, and a second heating device are connected in parallel; the first heating device is installed in the driver's cabin, and the second heating device is installed in the passenger cabin.

[0016] The present invention also provides an operating mode based on the above-mentioned hydrogen fuel cell hybrid vehicle thermal management system, the operating mode including:

[0017] Low-temperature rapid start mode: During low-temperature startup, the fuel cell cooling system's system PTC and the fuel cell heat utilization system's warm air-to-liquid heater are combined. The coolant in the fuel cell cooling system is heated twice as it passes through the heat exchanger and the system PTC, increasing the coolant temperature rise rate and enabling rapid low-temperature startup of the fuel cell system.

[0018] Summer power generation mode: The fluid medium in the fuel cell heat utilization system is vaporized by using a heat exchanger, the valve opening of the first three-way valve and the second three-way valve is controlled, the speed of the heater water pump is controlled, and the valve opening of the bypass valve and the heater bypass valve is controlled, and the vaporized fluid medium is used to drive the turbine generator to generate electricity;

[0019] Winter heating mode: By using the heat exchanger and the warm air gas-liquid heater, the valve opening of the first three-way valve and the second three-way valve is controlled, the speed of the warm air water pump, the valve opening of the bypass valve and the warm air bypass valve are controlled, and the heating unit is used to meet heating needs at different temperatures;

[0020] Winter power generation and heating mode: When the heat generated by the fuel cell system still meets the working conditions of the turbine power generation unit under the premise of heating, the fluid medium in the fuel cell heat utilization system is first vaporized, and the vaporized fluid medium is used to drive the turbine generator to generate electricity; then the fluid medium passes through the first heating device and the second heating device to meet the heating needs.

[0021] Furthermore, the low-temperature rapid start-up mode is specifically as follows: during the low-temperature start-up of the fuel cell system, in the initial stage, the A inlet of the thermostat and the C outlet of the thermostat are opened, and the B outlet of the thermostat is closed. As the temperature of the coolant measured by the first temperature sensor arranged at the inlet of the cooling path of the fuel cell stack continues to rise, the opening of the C outlet of the thermostat gradually decreases, and the opening of the B outlet of the thermostat gradually increases; until the B outlet of the thermostat is opened and the C outlet of the thermostat is closed; the A inlet of the first three-way valve and the C outlet of the first three-way valve are opened, and the B outlet of the first three-way valve is closed; the C inlet of the second three-way valve and the B outlet of the second three-way valve are opened, and the A inlet of the second three-way valve is closed.

[0022] Furthermore, the summer power generation mode is specifically as follows: when the heat generated by the fuel cell system meets the working conditions of the turbine power generation unit, open the A inlet of the thermostat and the B outlet of the thermostat, and close the C outlet of the thermostat; open the A inlet of the first three-way valve and the B outlet of the first three-way valve, and close the C outlet of the first three-way valve; open the A inlet of the second three-way valve and the B outlet of the second three-way valve, and close the C inlet of the second three-way valve; open the warm air bypass valve, and close the bypass valve.

[0023] Furthermore, the winter heating mode is specifically as follows: when the vehicle needs heating, open the A inlet of the thermostat and the B outlet of the thermostat, and close the C outlet of the thermostat; open the A inlet of the first three-way valve and the B outlet of the first three-way valve, and close the C outlet of the first three-way valve; open the A inlet of the second three-way valve and the B outlet of the second three-way valve, and close the C inlet of the second three-way valve; open the bypass valve and close the warm air bypass valve.

[0024] Furthermore, the winter power generation and heating mode is specifically as follows: when the vehicle meets the power generation conditions while being heated, open the A inlet of the thermostat and the B outlet of the thermostat, and close the C outlet of the thermostat; open the A inlet of the first three-way valve and the B outlet of the first three-way valve, and close the C outlet of the first three-way valve; open the A inlet of the second three-way valve and the B outlet of the second three-way valve, and close the C inlet of the second three-way valve; close the bypass valve and the warm air bypass valve.

[0025] Compared with the prior art, the present invention has the following beneficial effects:

[0026] (1) The fuel cell cooling system and the fuel cell heat utilization system are connected by setting a heat exchanger. A warm air unit and a turbine power generation unit are set in the fuel cell heat utilization system. Different working modes are selected according to different working environments. When heating is required, the waste heat of the fuel cell system is fully utilized for heating. When heating is not required, the waste heat is converted into electrical energy for storage through the turbine generator. This reduces the power required for heat dissipation of the fuel cell cooling equipment and improves the energy efficiency of the fuel cell system.

[0027] (2) In the summer when no heating is required, the fluid medium in the fuel cell heat utilization system exchanges heat with the coolant in the fuel cell cooling system when flowing through the heat exchanger to increase the temperature of the fluid medium in the fuel cell heat utilization system, thereby vaporizing the fluid medium for use in the turbine power generation unit to generate electricity, and storing the electricity generated by the turbine generator, thereby making full use of the waste heat of the fuel cell system and improving the energy utilization rate of the fuel cell.

[0028] (3) When the vehicle heating demand is high, the fluid medium in the fuel cell heat utilization system is heated through the heat exchanger. If the temperature rise of the heat exchanger is insufficient, the warm air gas-liquid heater can be started to heat the fluid medium for a second time. Then, the fluid medium in the fuel cell heat utilization system is made to flow through the first warm air device and the second warm air device to transfer heat and heat the driver's cabin and passenger cabin of the vehicle.

[0029] (4) When the heat generated by the fuel cell system still meets the working conditions of the turbine power generation unit under the premise of heating, the fluid medium in the fuel cell heat utilization system is first vaporized, and the vaporized fluid medium is used to drive the turbine generator to generate electricity; then the fluid medium passes through the recovery and reuse device and merges with the liquid flowing through the gas-liquid separation device, and flows into the first heating device and the second heating device to meet the heating needs, optimize the energy structure, maximize the utilization of the waste heat of the fuel cell system, and improve the energy utilization rate of the fuel cell.

[0030] (5) The coolant in the fuel cell cooling system exchanges heat with the higher temperature fluid medium in the fuel cell heat utilization system when flowing through the heat exchanger, thereby achieving the first temperature rise of the coolant in the fuel cell cooling system. When passing through the system PTC, the second temperature rise is achieved, thereby accelerating the temperature rise rate of the coolant to increase the temperature of the coolant when entering the fuel cell stack. The coolant with a higher temperature after two temperature rises transfers heat to the fuel cell stack when flowing through the fuel cell stack with a lower temperature, causing the temperature of the fuel cell stack to rise rapidly, thereby achieving low-temperature rapid start-up of the fuel cell engine, so that the fuel cell engine can reach the optimal state more quickly for use.

[0031] Other features and advantages of the present invention will be described in the following description, and in part will become apparent from the description, or will be understood by practicing the present invention. The purpose and other advantages of the present invention can be realized and obtained by the structures pointed out in the description and the drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following is a brief introduction to the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0033] Figure 1 A schematic structural diagram of a thermal management system for a hydrogen fuel cell hybrid vehicle according to an embodiment of the present invention is shown.

[0034] In the figure: 1. System radiator; 2. System PTC; 3. Thermostat; 4. Third temperature sensor; 5. System water pump; 6. System expansion tank; 7. Second temperature sensor; 8. First temperature sensor; 9. Fuel cell stack; 10. Seventh temperature sensor; 11. Second three-way valve; 12. Warm air water pump; 13. Fifth temperature sensor; 14. Heat exchanger; 15. Fourth temperature sensor; 16. Warm air gas-liquid heater; 17. First three-way valve; 18. Turbine generator controller; 19. Turbine generator; 20. Gas-liquid separation device; 21. Bypass valve; 22. Recycling device; 23. Warm air bypass valve; 24. First warm air device; 25. Second warm air device; 26. Sixth temperature sensor; 27. Eighth temperature sensor. DETAILED DESCRIPTION

[0035] To make the objectives, technical solutions, and advantages of the embodiments of the present invention more clear, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts shall fall within the scope of protection of the present invention.

[0036] The embodiment of the present invention proposes a thermal management system for a hydrogen fuel cell hybrid vehicle, as shown in the attached Figure 1 As shown, the thermal management system includes a fuel cell cooling system and a fuel cell heat utilization system;

[0037] The fuel cell heat utilization system includes a first outlet of a heat exchanger 14, a warm air gas-liquid heater 16, a first three-way valve 17, a turbine power generation unit, a warm air unit, a second three-way valve 11, a warm air water pump 12, and a first inlet of the heat exchanger 14, which are connected in sequence; the fluid medium in the fuel cell heat utilization system is a phase change material;

[0038] Specifically, the fluid medium in the fuel cell heat utilization system is a gas-liquid phase change material, which is liquid at room temperature, vaporizes into gas after absorbing heat and heating to a certain temperature, and liquefies into liquid after releasing heat and cooling to a certain temperature.

[0039] The fuel cell cooling system and the fuel cell heat utilization system are connected via a heat exchanger 14;

[0040] The turbine power generation unit is used to generate electricity using the heat of the fuel cell cooling system; the heater unit is arranged in the driver's cabin and the passenger cabin and is used to provide heating using the heat of the fuel cell cooling system.

[0041] The fuel cell cooling system includes a system expansion water tank 6, a system water pump 5, a thermostat 3, a system PTC2, and a system radiator 1; the cooling path outlet of the fuel cell stack 9 is connected to the system water pump 5, the second inlet of the heat exchanger 14, the second outlet of the heat exchanger 14, and the A inlet of the thermostat 3 in sequence, the B outlet of the thermostat 3 is connected to the system radiator 1, and the C outlet of the thermostat 3 is connected to the system PTC2. The system radiator 1 and the system PTC2 are both connected to the cooling path inlet of the fuel cell stack 9; the fluid medium in the fuel cell cooling system is fuel cell coolant; a system expansion water tank 6 for replenishing the fuel cell coolant is also provided between the cooling path outlet of the fuel cell stack and the system water pump 5.

[0042] The first outlet of the heat exchanger 14 is connected to the warm air gas-liquid heater 16, the A inlet of the first three-way valve 17, the B outlet of the first three-way valve 17 is connected to the turbine power generation unit and the warm air unit in sequence, and then connected to the A inlet of the second three-way valve 11; the C outlet of the first three-way valve 17 is connected to the C inlet of the second three-way valve 11; the B outlet of the second three-way valve 11 is connected to the warm air water pump 12 and the first inlet of the heat exchanger 14 in sequence.

[0043] The turbine power generation unit includes a gas-liquid separation device 20, a turbine generator 19, a turbine power generation controller 18, a recycling device 22 and a bypass valve 21. The inlet of the turbine power generation unit is a T-branch structure. The B outlet of the first three-way valve 17 is connected to the inlet of the T-branch structure. The first outlet of the T-branch structure is connected to the bypass valve 21, and the second outlet of the T-branch structure is connected to the gas-liquid separation device 20; the gas outlet of the gas-liquid separation device 20 is connected to the gas inlet of the turbine generator 19, and the gas outlet of the turbine generator 19 is connected to the inlet of the recycling device 22. The outlet of the recycling device 22, the liquid outlet of the gas-liquid separation device 20 and the outlet of the bypass valve 21 are connected to the inlet of the warm air unit together. The turbine generator 19 is electrically connected to the turbine power generation controller 18.

[0044] The heating unit is a parallel structure of a heating bypass valve 23, a first heating device 24, and a second heating device 25; the first heating device 24 is installed in the driver's cabin, and the second heating device 25 is installed in the passenger cabin.

[0045] A first temperature sensor 8 is arranged at the inlet of the cooling path of the fuel cell stack 9, which is used to measure the temperature of the coolant in the fuel cell cooling system; a second temperature sensor 7 is arranged at the outlet of the cooling path of the fuel cell stack 9; a third temperature sensor 4 is arranged at the second outlet of the heat exchanger 14; a fourth temperature sensor 15 is arranged at the first outlet of the heat exchanger 14, which is used to measure the temperature of the fluid medium in the fuel cell heat utilization system; a fifth temperature sensor 13 is arranged at the first inlet of the heat exchanger; a sixth temperature sensor 26 is arranged in the warm air unit; a seventh temperature sensor 10 for monitoring the ambient temperature is arranged in the fuel cell system; and an eighth temperature sensor 27 is arranged in the passenger compartment.

[0046] The present invention also provides an operating mode based on the above-mentioned hydrogen fuel cell hybrid vehicle thermal management system, the operating mode including:

[0047] Low temperature quick start mode:

[0048] During low-temperature startup, the system PTC2 of the fuel cell cooling system and the warm air-liquid heater 16 of the fuel cell heat utilization system are used in combination. The coolant in the fuel cell cooling system is heated twice when passing through the heat exchanger 14 and the system PTC2, and the temperature rise rate of the coolant is increased, thereby causing the temperature of the fuel cell stack 9 to rise rapidly, thereby achieving rapid low-temperature startup of the fuel cell system.

[0049] During the low-temperature startup of the fuel cell system, in the initial stage, the A inlet and the C outlet of the thermostat are opened, and the B outlet of the thermostat is closed. As the temperature of the coolant measured by the first temperature sensor provided at the inlet of the cooling path of the fuel cell stack continues to rise, the opening degree of the C outlet of the thermostat gradually decreases, and the opening degree of the B outlet of the thermostat gradually increases until the B outlet of the thermostat opens and the C outlet of the thermostat closes. The A inlet and the C outlet of the first three-way valve 17 are opened, and the B outlet of the first three-way valve 17 is closed. The C inlet and the B outlet of the second three-way valve 11 are opened, and the A inlet of the second three-way valve 11 is closed.

[0050] The coolant in the fuel cell cooling system flows out from the cooling path outlet of the fuel cell stack 9, passes through the system water pump 5, the second inlet of the heat exchanger 14, the second outlet of the heat exchanger 14, the inlet A of the thermostat 3, the outlet C of the thermostat 3, the system PTC2, and finally enters the fuel cell stack 9 through the cooling path inlet;

[0051] The fluid medium in the fuel cell heat utilization system flows out from the first outlet of the heat exchanger 14, passes through the warm air gas-liquid heater 16, the A inlet of the first three-way valve 17, the C outlet of the first three-way valve 17, the C inlet of the second three-way valve 11, the B outlet of the second three-way valve 11, the warm air water pump 12, and finally enters the heat exchanger through the first inlet of the heat exchanger 14;

[0052] In the initial state, the system PTC2 and the warm air gas-liquid heater 16 are both operated at full power to heat the coolant and the fluid medium respectively. Then, according to the temperature of the coolant in the fuel cell cooling system measured by the first temperature sensor 8 set at the cooling path entrance of the fuel cell stack 9, and the temperature of the fluid medium in the fuel cell heat utilization system measured by the fourth temperature sensor 15 set at the first outlet of the heat exchanger 14, the operating power of the system PTC2 and the warm air gas-liquid heater 16 are adjusted respectively, so that the fluid medium in the fuel cell heat utilization system transfers heat to the coolant in the fuel cell cooling system when flowing through the heat exchanger 14. The coolant in the fuel cell cooling system exchanges heat with the higher-temperature fluid medium in the fuel cell heat utilization system when flowing through the heat exchanger 14, realizing the first temperature rise of the coolant in the fuel cell cooling system. When passing through the system PTC2, the second temperature rise is realized, thereby accelerating the temperature rise rate of the coolant to increase the temperature of the coolant when entering the fuel cell stack 9. The coolant with a higher temperature after two temperature rises transfers heat to the fuel cell stack 9 when flowing through the fuel cell stack 9 with a lower temperature, causing the temperature of the fuel cell stack 9 to rise rapidly, thereby realizing low-temperature rapid start-up of the fuel cell engine, so that the fuel cell engine can reach the optimal state faster for use.

[0053] Summer power generation mode:

[0054] In summer, waste heat from the fuel cell system is used to generate electricity. The fluid medium in the fuel cell heat utilization system is vaporized using a heat exchanger 14, the valve openings of the first three-way valve 17 and the second three-way valve 11 are controlled, the speed of the warm air water pump 12 is controlled, and the valve openings of the bypass valve 21 and the warm air bypass valve 23 are controlled. The vaporized fluid medium is used to drive the turbine generator 19 to generate electricity, thereby realizing waste heat utilization, making full use of the waste heat of the fuel cell system, and improving the energy utilization rate of the fuel cell.

[0055] When the heat generated by the fuel cell system meets the working conditions of the turbine power generation unit, the A inlet and the B outlet of the thermostat 3 are opened, and the C outlet of the thermostat 3 is closed; the A inlet and the B outlet of the first three-way valve 17 are opened, and the C outlet of the first three-way valve 17 is closed; the A inlet and the B outlet of the second three-way valve 11 are opened, and the C inlet of the second three-way valve 11 is closed; the warm air bypass valve 23 is opened, and the bypass valve 21 is closed;

[0056] The coolant in the fuel cell cooling system flows out from the cooling path outlet of the fuel cell stack 9, passes through the system water pump 5, the second inlet of the heat exchanger 14, the second outlet of the heat exchanger 14, the A inlet of the thermostat 3, the B outlet of the thermostat 3, the system radiator 1, and finally enters the stack through the cooling path inlet of the fuel cell stack 9; whether the fan of the system radiator 1 works depends on whether the temperature of the coolant in the fuel cell cooling system is reduced to an appropriate temperature after being cooled when passing through the heat exchanger 14.

[0057] The fluid medium in the fuel cell heat utilization system flows out from the first outlet of the heat exchanger 14, passes through the warm air gas-liquid heater 16, the A inlet of the first three-way valve 17, the B outlet of the first three-way valve 17, and the gas-liquid separation device 20 in sequence. The part of the fluid medium that is vaporized in the gas-liquid separation device 20 flows out through the gas outlet of the gas-liquid separation device 20 and enters the gas inlet of the turbine generator 19, driving the turbine generator 19 to generate electricity; the liquid part in the gas-liquid separation device 20 flows out through the liquid outlet of the gas-liquid separation device 20, and merges with the fluid medium flowing out of the recycling device 22, and then passes through the warm air unit, the A inlet of the second three-way valve 11, the B outlet of the second three-way valve 11, the warm air water pump 12 in sequence, and finally enters the heat exchanger through the first inlet of the heat exchanger 14; and the fans of the first warm air device 24 and the second warm air device 25 in the warm air unit are not working.

[0058] In the summer when no heating is required, the fluid medium in the fuel cell heat utilization system exchanges heat with the coolant in the fuel cell cooling system when flowing through the heat exchanger 14 to increase the temperature of the fluid medium in the fuel cell heat utilization system, thereby vaporizing the fluid medium for use in the turbine power generation unit to generate electricity, and storing the electrical energy generated by the turbine generator 19, thereby making full use of the waste heat of the fuel cell system and improving the energy utilization rate of the fuel cell.

[0059] Winter heating mode:

[0060] The heating requirements are different under different winter ambient temperatures. By using the heat exchanger 14 and the warm air gas-liquid heater 16, the valve openings of the first three-way valve 17 and the second three-way valve 11 are controlled, and the speed of the warm air water pump 12 and the valve openings of the bypass valve 21 and the warm air bypass valve 23 are controlled to meet the heating requirements of different temperatures, maximize the utilization of the waste heat of the fuel cell system, reduce the power consumption of the warm air gas-liquid heater 16, and improve the energy utilization rate of the fuel cell system.

[0061] When the vehicle needs heating, the inlet A of the thermostat 3 and the outlet B of the thermostat 3 are opened, and the outlet C of the thermostat 3 is closed; the inlet A of the first three-way valve 17 and the outlet B of the first three-way valve 17 are opened, and the outlet C of the first three-way valve 17 is closed; the inlet A of the second three-way valve 11 and the outlet B of the second three-way valve 11 are opened, and the inlet C of the second three-way valve 11 is closed; the bypass valve 21 is opened, and the heating bypass valve 23 is closed;

[0062] The coolant in the fuel cell cooling system flows out from the cooling path outlet of the fuel cell stack 9, passes through the system water pump 5, the second inlet of the heat exchanger 14, the second outlet of the heat exchanger 14, the inlet A of the thermostat 3, the outlet B of the thermostat 3, the system radiator 1, and finally enters the fuel cell stack through the cooling path inlet of the fuel cell stack 9;

[0063] The fluid medium in the fuel cell heat utilization system flows out from the first outlet of the heat exchanger 14, passes through the warm air gas-liquid heater 16, the A inlet of the first three-way valve 17, the B outlet of the first three-way valve 17, and the bypass valve 21, and then enters the first warm air device 24 and the second warm air device 25 respectively. Then, it passes through the A inlet of the second three-way valve 11, the B outlet of the second three-way valve 11, the warm air water pump 12, and finally enters the heat exchanger through the first inlet of the heat exchanger 14;

[0064] When the vehicle's heating demand is high, the heat exchanger 14 is used to heat the fluid medium in the fuel cell heat utilization system. When the temperature of the fluid medium flowing through the heat exchanger 14 is not high enough, the warm air gas-liquid heater 16 can also be started to heat the fluid medium a second time, so that all the fluid medium in the fuel cell heat utilization system flows through the first warm air device 24 and the second warm air device 25 to transfer heat and heat the driver's cabin and passenger cabin of the vehicle. According to the vehicle's heating demand, the working state and heating power of the warm air gas-liquid heater 16 are controlled. When the vehicle's heating demand is high and the use of waste heat alone cannot meet the demand, the heating function of the warm air gas-liquid heater 16 is turned on. The fluid medium in the fuel cell heat utilization system exchanges heat with the coolant in the fuel cell cooling system for the first time when flowing through the heat exchanger 14, and exchanges heat with the coolant for the second time when flowing through the warm air gas-liquid heater 16, thereby increasing the temperature of the fluid medium in the fuel cell heat utilization system to meet the higher heating temperature demand of the vehicle. In addition, the heating power of the warm air gas-liquid heater 16 is adjusted according to the heating temperature of the vehicle to achieve different heating temperatures.

[0065] Winter power generation and heating mode:

[0066] When the heat generated by the fuel cell system still meets the working conditions of the turbine power generation unit under the premise of heating, the fluid medium in the fuel cell heat utilization system is first vaporized, and the vaporized fluid medium is used to drive the turbine generator 19 to generate electricity; then the fluid medium passes through the first heating device 24 and the second heating device 25 to meet the heating needs, optimize the energy structure, maximize the utilization of the waste heat of the fuel cell system, and improve the energy utilization rate of the fuel cell.

[0067] When the vehicle meets the power generation conditions while being heated, the inlet A and outlet B of the thermostat 3 are opened, and the outlet C of the thermostat 3 is closed; the inlet A and outlet B of the first three-way valve 17 are opened, and the outlet C of the first three-way valve 17 is closed; the inlet A and outlet B of the second three-way valve 11 are opened, and the inlet C of the second three-way valve 11 is closed; the bypass valve 21 and the heating bypass valve 23 are closed;

[0068] The coolant in the fuel cell cooling system flows out from the cooling path outlet of the fuel cell stack 9, passes through the system water pump 5, the second inlet of the heat exchanger 14, the second outlet of the heat exchanger 14, the inlet A of the thermostat 3, the outlet B of the thermostat 3, the system radiator 1, and finally enters the fuel cell stack through the cooling path inlet of the fuel cell stack 9;

[0069] The fluid medium in the fuel cell heat utilization system flows out from the first outlet of the heat exchanger 14, passes through the warm air gas-liquid heater 16, the A inlet of the first three-way valve 17, the B outlet of the first three-way valve 17, and the gas-liquid separation device 20 in sequence. The portion of the fluid medium that is vaporized in the gas-liquid separation device 20 flows out through the gas outlet of the gas-liquid separation device 20 and enters the gas inlet of the turbine generator 19, driving the turbine generator 19 to generate electricity; the liquid portion in the gas-liquid separation device 20 flows out through the liquid outlet of the gas-liquid separation device 20 and merges with the fluid medium flowing out of the recycling device 22, and then enters the first warm air device 24 and the second warm air device 25 respectively, and then passes through the A inlet of the second three-way valve 11, the B outlet of the second three-way valve 11, the warm air water pump 12, and finally enters the heat exchanger through the first inlet of the heat exchanger 14;

[0070] The fluid medium in the fuel cell heat utilization system undergoes a first heat exchange and temperature increase with the coolant in the fuel cell cooling system when flowing through the heat exchanger 14. The fourth temperature sensor 15 provided at the first outlet of the heat exchanger 14 measures the temperature of the fluid medium in the fuel cell heat utilization system. The fuel cell system controls the working state and heating power of the warm air gas-liquid heater 16 according to the measured temperature, the heat generation of the fuel cell system and the state of the turbine power generation unit, and assists in heating the fluid medium in the fuel cell heat utilization system, i.e., performs a second heat transfer and temperature increase, so that the temperature of the fluid medium in the fuel cell heat utilization system is partially vaporized for power generation by the turbine power generation unit. In addition, the opening of the warm air bypass valve 23 can be controlled to achieve heating needs at different temperatures. The above method can optimize the energy structure, maximize the use of waste heat from the fuel cell system, and improve the energy utilization rate of the fuel cell system.

[0071] The fuel cell cooling system and the fuel cell heat utilization system are connected by setting a heat exchanger. By setting a warm air unit and a turbine power generation unit in the fuel cell heat utilization system, different working modes are selected according to different working environments. When heating is needed, the waste heat of the fuel cell system is fully utilized for heating. When heating is not needed, the waste heat is converted into electrical energy for storage through the turbine generator. This reduces the power required for heat dissipation of the fuel cell cooling equipment and improves the energy efficiency of the fuel cell system.

[0072] Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein; and these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A thermal management system for a hydrogen fuel cell hybrid vehicle, characterized in that: The thermal management system includes a fuel cell cooling system and a fuel cell heat utilization system; The fuel cell heat utilization system includes a first outlet of a heat exchanger, a warm air gas-liquid heater, a first three-way valve, a turbine power generation unit, a warm air unit, a second three-way valve, a warm air water pump, and a first inlet of the heat exchanger, which are connected in sequence; the fluid medium in the fuel cell heat utilization system is a phase change material; The fuel cell cooling system and the fuel cell heat utilization system are connected via a heat exchanger; The turbine power generation unit is used to generate electricity using the heat of the fuel cell cooling system; the heater unit is arranged in the driver's cabin and the passenger cabin and is used to provide heating using the heat of the fuel cell cooling system.

2. The hydrogen fuel cell hybrid vehicle thermal management system according to claim 1, characterized in that: The fuel cell cooling system includes a system expansion water tank, a system water pump, a thermostat, a system PTC, and a system radiator; the cooling path outlet of the fuel cell stack is connected to the system water pump, the second inlet of the heat exchanger, the second outlet of the heat exchanger, and the A inlet of the thermostat in sequence, the B outlet of the thermostat is connected to the system radiator, and the C outlet of the thermostat is connected to the system PTC. The system radiator and the system PTC are both connected to the cooling path inlet of the fuel cell stack; a system expansion water tank for replenishing the fuel cell coolant is also provided between the cooling path outlet of the fuel cell stack and the system water pump.

3. The hydrogen fuel cell hybrid vehicle thermal management system according to claim 2, characterized in that: The first outlet of the heat exchanger is connected to the warm air gas-liquid heater, the A inlet of the first three-way valve, the B outlet of the first three-way valve is connected to the turbine power generation unit and the warm air unit in sequence, and then connected to the A inlet of the second three-way valve; the C outlet of the first three-way valve is connected to the C inlet of the second three-way valve; the B outlet of the second three-way valve is connected to the warm air water pump and the first inlet of the heat exchanger in sequence.

4. The hydrogen fuel cell hybrid vehicle thermal management system according to claim 3, characterized in that: The turbine power generation unit includes a gas-liquid separation device, a turbine generator, a turbine power generation controller, a recycling device and a bypass valve. The inlet of the turbine power generation unit is a T-branch structure. The B outlet of the first three-way valve is connected to the inlet of the T-branch structure. The first outlet of the T-branch structure is connected to the bypass valve, and the second outlet of the T-branch structure is connected to the gas-liquid separation device; the gas outlet of the gas-liquid separation device is connected to the gas inlet of the turbine generator, and the gas outlet of the turbine generator is connected to the inlet of the recycling device. The outlet of the recycling device, the liquid outlet of the gas-liquid separation device and the outlet of the bypass valve are connected to the inlet of the warm air unit together, and the turbine generator is electrically connected to the turbine power generation controller.

5. The hydrogen fuel cell hybrid vehicle thermal management system according to claim 4, characterized in that: The heating unit is a structure in which a heating bypass valve, a first heating device and a second heating device are connected in parallel; the first heating device is installed in the driver's cabin, and the second heating device is installed in the passenger cabin.

6. An operating mode of a thermal management system for a hydrogen fuel cell hybrid vehicle according to any one of claims 1 to 5, characterized in that: The working modes include: Low-temperature rapid start mode: During low-temperature startup, the fuel cell cooling system's system PTC and the fuel cell heat utilization system's warm air-to-liquid heater are combined. The coolant in the fuel cell cooling system is heated twice as it passes through the heat exchanger and the system PTC, increasing the coolant temperature rise rate and enabling rapid low-temperature startup of the fuel cell system. Summer power generation mode: The fluid medium in the fuel cell heat utilization system is vaporized by using a heat exchanger, the valve opening of the first three-way valve and the second three-way valve is controlled, the speed of the heater water pump is controlled, and the valve opening of the bypass valve and the heater bypass valve is controlled, and the vaporized fluid medium is used to drive the turbine generator to generate electricity; Winter heating mode: By using the heat exchanger and the warm air gas-liquid heater, the valve opening of the first three-way valve and the second three-way valve is controlled, the speed of the warm air water pump, the valve opening of the bypass valve and the warm air bypass valve are controlled, and the heating unit is used to meet heating needs at different temperatures; Winter power generation and heating mode: When the heat generated by the fuel cell system still meets the working conditions of the turbine power generation unit under the premise of heating, the fluid medium in the fuel cell heat utilization system is first vaporized, and the vaporized fluid medium is used to drive the turbine generator to generate electricity; then the fluid medium passes through the recovery and reuse device and merges with the liquid flowing through the gas-liquid separation device, and flows into the first heating device and the second heating device to meet the heating needs. Then the fluid medium passes through the first heating device and the second heating device to meet the heating needs.

7. The operating mode of the thermal management system for a hydrogen fuel cell hybrid vehicle according to claim 1, characterized in that: The low-temperature rapid start mode is specifically as follows: during the low-temperature start-up of the fuel cell system, in the initial stage, the thermostat inlet A and the thermostat outlet C are opened, and the thermostat outlet B is closed. As the coolant temperature measured by the first temperature sensor provided at the inlet of the cooling path of the fuel cell stack continues to rise, the opening of the thermostat outlet C gradually decreases, and the opening of the thermostat outlet B gradually increases until the thermostat outlet B opens and the thermostat outlet C closes. Open the A inlet of the first three-way valve and the C outlet of the first three-way valve, and close the B outlet of the first three-way valve; Open the C inlet of the second three-way valve and the B outlet of the second three-way valve, and close the A inlet of the second three-way valve.

8. The operating mode of the thermal management system for a hydrogen fuel cell hybrid vehicle according to claim 1, characterized in that: The summer power generation mode is specifically as follows: when the heat generated by the fuel cell system meets the working conditions of the turbine power generation unit, the thermostat A inlet and the thermostat B outlet are opened, and the thermostat C outlet is closed; Open the A inlet of the first three-way valve and the B outlet of the first three-way valve, and close the C outlet of the first three-way valve; Open the A inlet of the second three-way valve and the B outlet of the second three-way valve, and close the C inlet of the second three-way valve; Open the heater bypass valve and close the bypass valve.

9. The operating mode of the thermal management system for a hydrogen fuel cell hybrid vehicle according to claim 3, characterized in that: The winter heating mode is specifically as follows: when the vehicle needs heating, the A inlet of the thermostat and the B outlet of the thermostat are opened, and the C outlet of the thermostat is closed; the A inlet of the first three-way valve and the B outlet of the first three-way valve are opened, and the C outlet of the first three-way valve is closed; Open the A inlet of the second three-way valve and the B outlet of the second three-way valve, and close the C inlet of the second three-way valve; Open the bypass valve and close the heater bypass valve.

10. The operating mode of the thermal management system for a hydrogen fuel cell hybrid vehicle according to claim 3, characterized in that: The winter power generation and heating mode is specifically as follows: when the vehicle is heating and meets the power generation conditions, the thermostat A inlet and the thermostat B outlet are opened, and the thermostat C outlet is closed; the first three-way valve A inlet and the first three-way valve B outlet are opened, and the first three-way valve C outlet is closed; Open the A inlet of the second three-way valve and the B outlet of the second three-way valve, and close the C inlet of the second three-way valve; close the bypass valve and the warm air bypass valve.

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