Fuel cell adaptive nitrogen venting control method and fuel cell system

Abstract

The application provides a fuel cell adaptive nitrogen discharge control method and a fuel cell system, and belongs to the technical field of fuel cells, and solves the problems that the prior art is not suitable for complex application scenarios and is prone to hydrogen waste and single-piece voltage being too low. The method comprises the following steps: S1, determining the hydrogen concentration change curve of the hydrogen cavity under different environmental pressures and different environmental temperatures when the fuel cell is shut down and left for different time; S2, when the fuel cell is started this time, the last shutdown time, the environmental pressure and the environmental temperature of the fuel cell are obtained, and the hydrogen concentration in the hydrogen cavity at the current time is predicted in combination with the hydrogen concentration change curve in the hydrogen cavity; S3, whether the predicted hydrogen concentration in the hydrogen cavity of the fuel cell is lower than the target concentration is identified, if yes, the fuel cell system starting process is not controlled to perform the nitrogen discharge operation, otherwise, the nitrogen discharge time is further determined according to the predicted hydrogen concentration in the hydrogen cavity of the fuel cell, and the fuel cell system starting process is controlled to perform the nitrogen discharge operation.

Description

Technical Field

[0001] This invention relates to the field of fuel cell technology, and in particular to an adaptive nitrogen emission control method and fuel cell system for fuel cells. Background Technology

[0002] During fuel cell operation, it is essential to maintain a certain hydrogen concentration in the hydrogen chamber to ensure a sufficient supply of hydrogen and prevent low voltage on individual cells. Current technology typically involves controlling the opening cycle, opening time, and closing time of the nitrogen purging valve during startup to replace the nitrogen-dominant gas that entered the hydrogen chamber after the last shutdown. This ensures a sufficient hydrogen concentration in the hydrogen chamber upon entering fuel cell operation, preventing low voltage on individual cells from affecting the stack's lifespan.

[0003] Currently, the nitrogen purging valve in fuel cell systems is typically controlled using a fixed opening cycle and a fixed opening time. This control scheme is calibrated based on a hydrogen concentration of 0 in the hydrogen chamber. If the opening frequency of the nitrogen purging valve is too low or the opening time is too short, it will cause excessive impurities in the stack anode, resulting in low voltage per cell.

[0004] In the use of fuel cells, the application scenarios are numerous and complex. The solution of fixing the opening cycle and opening time of the nitrogen venting valve does not have the ability to recognize the scenario and cannot avoid the phenomenon of low voltage of a single cell. If the system is turned on immediately after being turned off, the hydrogen concentration in the hydrogen chamber is relatively high. If the nitrogen venting valve opens more frequently or for a longer time, it will release excessive hydrogen, resulting in waste of hydrogen resources and a significant reduction in system efficiency. Summary of the Invention

[0005] Based on the above analysis, the present invention aims to provide an adaptive nitrogen emission control method for fuel cells to solve the problems that existing technologies are not suitable for complex application scenarios and are prone to hydrogen waste and low single-cell voltage.

[0006] On one hand, embodiments of the present invention provide an adaptive nitrogen emission control method for fuel cells, comprising the following steps:

[0007] S1. Determine the hydrogen concentration change curves in the hydrogen chamber of the fuel cell under different environmental pressures and temperatures and after being shut down and left to stand for different times.

[0008] S2. When the fuel cell is powered on this time, obtain the last shutdown time of the fuel cell, the ambient pressure, and the ambient temperature. Combine this with the hydrogen concentration change curve in the hydrogen chamber mentioned above to predict the hydrogen concentration in the hydrogen chamber of the fuel cell at the current moment.

[0009] S3. Identify whether the predicted hydrogen concentration in the hydrogen chamber of the fuel cell is lower than the target concentration. If so, control the fuel cell system to not perform nitrogen purging during startup. Otherwise, further determine the nitrogen purging time based on the predicted hydrogen concentration in the hydrogen chamber of the fuel cell, and control the fuel cell system to perform the nitrogen purging operation for that time during startup.

[0010] The beneficial effects of the above technical solution are as follows: It provides a control strategy for adaptively adjusting the nitrogen purging time of a fuel cell start-up, which adaptively adjusts the nitrogen purging cycle according to the usage scenario during the fuel cell start-up process to ensure that the fuel cell can quickly meet the hydrogen concentration required for normal operation. Dynamically adjusting the start-up nitrogen purging time ensures that the fuel cell system can achieve the operating hydrogen chamber concentration value when entering the operating state, avoiding low concentrations. It also avoids excessive hydrogen emissions due to excessively high nitrogen purging frequency or long start-up time, which could lead to excessively high exhaust hydrogen concentration and safety risks.

[0011] Based on the further improvement of the above-mentioned adaptive nitrogen emission control method for fuel cells, step S1 further includes:

[0012] S11. The hydrogen concentration change curves in the hydrogen chamber of the fuel cell were determined by experiment under different environmental pressures and temperatures and after being shut down and left to stand for different times.

[0013] S12. Upload the hydrogen concentration change curves in the hydrogen chamber of the fuel cell under different environmental pressures and temperatures and after being shut down and left to stand for different times to the cloud platform for storage.

[0014] Furthermore, step S2 further includes:

[0015] S21. Each time the fuel cell is shut down, its shutdown time is uploaded to the cloud platform for storage;

[0016] S22. When the fuel cell is powered on this time, the fuel cell system sends a command to the cloud platform to obtain the last shutdown time, obtains the last shutdown time of the fuel cell, and then determines the resting time;

[0017] S23. Obtain the current ambient pressure and ambient temperature. The fuel cell system continues to send instructions to the cloud platform to obtain the hydrogen concentration change curve in the hydrogen chamber that matches the current ambient temperature and ambient temperature. Obtain the corresponding hydrogen concentration change curve in the hydrogen chamber.

[0018] S24. Based on the obtained hydrogen concentration change curve in the hydrogen chamber and the settling time, the predicted value of the hydrogen concentration in the fuel cell hydrogen chamber at the current moment is obtained.

[0019] On the other hand, embodiments of the present invention provide a fuel cell system using the above-described method, including a controller performing the above-described method, and further including a fuel cell stack, an air control subsystem, a hydrogen control subsystem, a coolant control subsystem, and an exhaust system; wherein...

[0020] The coolant regulation subsystem further includes a radiator, a heater, and a thermostat; wherein, the input end of the thermostat is connected to the coolant outlet of the fuel cell stack, its output end is connected to the coolant inlet of the fuel cell stack via the radiator, and its output end is connected to the coolant inlet of the fuel cell stack via the heater.

[0021] The controller is also used to control the operation of the air conditioning subsystem, hydrogen conditioning subsystem, and coolant conditioning subsystem to complete the startup, operation, and shutdown of the fuel cell system.

[0022] Furthermore, the air control subsystem further includes an air compressor, intercooler, humidifier, and exhaust throttle valve; among which,

[0023] The air inlet of the fuel cell stack is connected to the output end of the air compressor via the first branch of the humidifier and the intercooler in sequence, and its air exhaust outlet is connected to the exhaust via the second branch of the humidifier and the exhaust throttle valve in sequence.

[0024] The controller's output is connected to the control terminals of the air compressor and the exhaust throttle valve.

[0025] Furthermore, the air control subsystem also includes a flow meter and an electrically controlled three-way valve; among which,

[0026] The flow meter is installed at the air inlet of the air compressor to obtain the flow rate of gas entering the air compressor and send it to the controller;

[0027] The electrically controlled three-way valve is located between the air compressor and the intercooler. Its input end is connected to the output end of the air compressor, its first output end is connected to the intercooler, its second output end is connected to the tail exhaust, and its control end is connected to the output end of the controller.

[0028] Furthermore, the hydrogen control subsystem further includes a hydrogen source, a pressure reducing valve, a shut-off valve, an ejector, a water distribution component, a near-end drain valve, and an exhaust valve; among which,

[0029] The ejector's jet inlet is connected to the hydrogen source via a shut-off valve and a pressure reducing valve. Its inlet is connected to the outlet of the water distribution unit, and its outlet is connected to the hydrogen inlet of the fuel cell stack. The water distribution unit's inlet is connected to the hydrogen tail gas outlet of the fuel cell stack, its outlet is connected to the tail discharge via a near-end drain valve, and its outlet is also connected to the tail discharge via an exhaust valve.

[0030] A liquid level sensor is installed inside the cavity of the water distribution component to obtain the liquid level height inside the water distribution component in real time and send it to the controller;

[0031] The controller's output is connected to the control terminals of the pressure reducing valve, shut-off valve, near-end drain valve, and exhaust valve.

[0032] Furthermore, the hydrogen control subsystem also includes safety valves, on / off valves, and a hydrogen circulation pump; among which,

[0033] The safety valve is located between the pressure reducing valve and the shut-off valve, and is integrated with the pressure reducing valve.

[0034] The outlet of the water distribution unit is connected to the hydrogen inlet of the fuel cell stack via a switch valve and a hydrogen circulation pump in sequence.

[0035] The controller's output is also connected to the control terminals of the safety valve, switching valve, and hydrogen circulation pump.

[0036] Furthermore, the hydrogen control subsystem also includes a main proportional valve and a bypass proportional valve; among which,

[0037] One output of the shut-off valve is connected to the hydrogen inlet of the fuel cell stack via the main proportional valve and ejector in sequence, and the other output is connected to the hydrogen inlet of the fuel cell stack via the bypass proportional valve.

[0038] The plate heat exchanger is located at the front end of the shut-off valve. Its input end is connected to the safety valve, and its output end is connected to the ejector's jet inlet via the shut-off valve and the main proportional valve in sequence.

[0039] Furthermore, the hydrogen control subsystem also includes a remote drain valve; and,

[0040] A drain outlet is located at the bottom opposite to the hydrogen control subsystem of the fuel cell stack. This drain outlet is connected to the tail drain via a remote drain valve.

[0041] The summary section is provided to present the chosen concepts in a simplified form, which will be further described in the detailed description below. The summary section is not intended to identify essential or essential features of the invention, nor is it intended to limit the scope of the invention. Attached Figure Description

[0042] The above and other objects, features and advantages of the present invention will become more apparent from the more detailed description of exemplary embodiments of the invention in conjunction with the accompanying drawings, wherein the same reference numerals generally represent the same parts.

[0043] Figure 1 A schematic diagram of the composition of the adaptive nitrogen emission control method for fuel cells in Example 1 is shown;

[0044] Figure 2 A schematic diagram of the bypass pipeline and valve layout in Embodiment 1 is shown;

[0045] Figure 3 A schematic diagram of the fuel cell system composition in Example 3 is shown;

[0046] Figure 4 A detailed schematic diagram of the fuel cell system of Example 3 is shown.

[0047] Figure Labels

[0048] P1 - First pressure sensor; P2 - Second pressure sensor; P3 - Third pressure sensor. Detailed Implementation

[0049] Embodiments of the invention will now be described in more detail with reference to the accompanying drawings. While embodiments of the invention are shown in the drawings, it should be understood that the invention can be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that the invention will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art.

[0050] The term "comprising" and its variations as used herein signify open inclusion, i.e., "including but not limited to". Unless otherwise stated, the term "or" means "and / or". The term "based on" means "at least partially based on". The terms "one example embodiment" and "one embodiment" mean "at least one example embodiment". The term "another embodiment" means "at least one additional embodiment". The terms "first", "second", etc., may refer to different or the same objects. Other explicit and implicit definitions may also be included below.

[0051] Example 1

[0052] One embodiment of the present invention discloses an adaptive nitrogen emission control method for fuel cells, such as... Figures 1-2 As shown, it includes the following steps:

[0053] S1. Determine the hydrogen concentration change curves in the hydrogen chamber of the fuel cell under different environmental pressures and temperatures and after being shut down and left to stand for different times.

[0054] Specifically, after the fuel cell system is shut down, the hydrogen concentration in the hydrogen chamber will continuously decrease. The change curve of the hydrogen concentration in the hydrogen chamber can be measured by test calibration under different environmental pressures and temperatures, and under different periods of time after the fuel cell is shut down and left to stand.

[0055] S2. When the fuel cell is powered on this time, obtain the last shutdown time of the fuel cell, the ambient pressure, and the ambient temperature. Combine this with the hydrogen concentration change curve in the hydrogen chamber mentioned above to predict the hydrogen concentration in the hydrogen chamber of the fuel cell at the current moment.

[0056] Specifically, the resting time can be determined by comparing the current time with the last shutdown time of the fuel cell. This resting time can be used to locate specific points on the hydrogen concentration change curve of the hydrogen chamber under the current ambient pressure and temperature, thus predicting the hydrogen concentration in the hydrogen chamber of the fuel cell at the current time.

[0057] S3. Identify whether the predicted hydrogen concentration in the hydrogen chamber of the fuel cell is lower than the target concentration. If so, control the fuel cell system to not perform nitrogen purging during startup (i.e., do not start nitrogen purging). Otherwise, further determine the nitrogen purging time based on the predicted hydrogen concentration in the hydrogen chamber of the fuel cell, and control the fuel cell system to perform the nitrogen purging operation for that time during startup (start nitrogen purging and adaptively determine the nitrogen purging time).

[0058] In practice, the above-described adaptive nitrogen purging control method for fuel cells is applicable to both fuel cell systems with and without nitrogen purging valves. For fuel cell systems without a dedicated nitrogen purging valve, the nitrogen purging function is achieved through an exhaust valve and a drain valve, as described in published Chinese patents CN219086009U and CN114361512B, as well as Example 2.

[0059] Compared with existing technologies, this embodiment provides a control strategy for adaptively adjusting the nitrogen purging time of a fuel cell start-up. This strategy adaptively adjusts the nitrogen purging cycle according to the usage scenario during fuel cell start-up to ensure that the fuel cell can quickly reach the hydrogen concentration required for normal operation. Dynamically adjusting the start-up nitrogen purging time ensures that the fuel cell system achieves the required hydrogen concentration in the operating chamber upon entering operation, avoiding situations where the concentration is too low. It also prevents excessive hydrogen emissions due to excessively high purging frequency or prolonged start-up time, which could lead to excessively high exhaust hydrogen concentration and safety risks.

[0060] Example 2

[0061] Based on Example 1, step S1 is further improved by including:

[0062] S11. The hydrogen concentration change curves in the hydrogen chamber of the fuel cell under different environmental pressures and temperatures and after being shut down and left to stand for different times were determined by experiment (a set of data);

[0063] S12. Upload the hydrogen concentration change curves (multiple sets of data) of the fuel cell under different environmental pressures and temperatures for different periods of time after shutdown to the cloud platform for storage.

[0064] Step S2 further includes:

[0065] S21. Each time the fuel cell is shut down, its shutdown time is uploaded to the cloud platform for storage;

[0066] S22. When the fuel cell is powered on this time, the fuel cell system sends a command to the cloud platform to obtain the last shutdown time, obtains the last shutdown time of the fuel cell, and then determines the resting time (obtained by subtracting the last shutdown time of the fuel cell from the current time).

[0067] S23. Obtain the current ambient pressure and ambient temperature. The fuel cell system (controller) continues to send instructions to the cloud platform to obtain the hydrogen concentration change curve in the hydrogen chamber that matches the current ambient temperature and ambient temperature. Obtain the corresponding hydrogen concentration change curve in the hydrogen chamber.

[0068] S24. Based on the obtained hydrogen concentration change curve in the hydrogen chamber and the settling time, the fuel cell system obtains the predicted value of the hydrogen concentration in the hydrogen chamber of the fuel cell at the current moment.

[0069] Preferably, the predicted hydrogen concentration in the hydrogen chamber of the fuel cell is not lower than the target concentration. Then, based on the predicted hydrogen concentration in the hydrogen chamber of the fuel cell, the nitrogen removal cycle and the start-up time in each cycle are determined, and the nitrogen removal operation of the fuel cell system during the start-up process is controlled to be performed according to the nitrogen removal cycle and the start-up time.

[0070] Compared with the prior art, the adaptive nitrogen emission control method for fuel cells provided in this embodiment has the following beneficial effects:

[0071] 1. By controlling the start-up nitrogen purging time of the fuel cell through the cloud platform, the fuel cell system can be ensured to quickly enter the operating state under the condition of meeting the hydrogen concentration requirements.

[0072] 2. After the fuel cell is shut down, the hydrogen concentration in the hydrogen chamber can be estimated in real time through the cloud platform in combination with different scenarios. The cloud platform identifies the fuel cell scenario (ambient pressure, ambient temperature) based on the fuel cell's last operating state, i.e., the time spent after shutdown (resting time), and determines the hydrogen concentration in the fuel cell's hydrogen chamber during the startup process.

[0073] 3. During fuel cell startup, the nitrogen purging cycle and start-up time are dynamically calibrated based on the different hydrogen concentrations in the hydrogen chamber. This ensures rapid entry into operation while avoiding excessive hydrogen emissions due to excessively high nitrogen purging frequency or prolonged start-up time.

[0074] Example 3

[0075] Another embodiment of the present invention discloses a fuel cell system with adaptive nitrogen removal function, including a fuel cell stack, an air control subsystem, a hydrogen control subsystem, a coolant control subsystem, an exhaust system, and a controller, such as... Figure 3 As shown.

[0076] The controller executes the program of the method described in Example 1 or 2 to perform nitrogen purging during the start-up process, and controls the operation of the air control subsystem, hydrogen control subsystem, and coolant control subsystem to complete the start-up, operation, and shutdown of the fuel cell system.

[0077] The air control subsystem supplies the necessary air for the cathode reaction via an air compressor. The hydrogen control subsystem maintains the hydrogen flow rate and pressure at the anode by controlling a proportional valve and a hydrogen circulation pump. The coolant control subsystem controls the large and small circulation branches via a thermostat, ensuring the system's normal operating temperature.

[0078] The coolant regulation subsystem further includes a radiator, heater, and thermostat, such as Figure 4 As shown in the figure. The input end of the thermostat is connected to the coolant outlet of the fuel cell stack, its output end one is connected to the coolant inlet of the fuel cell stack via a radiator, and its output end two is connected to the coolant inlet of the fuel cell stack via a heater.

[0079] The air control subsystem further includes an air compressor, an intercooler, a humidifier, and a tailpipe throttle. The air inlet of the fuel cell stack connects sequentially to the output of the air compressor via branch line one of the humidifier and the intercooler. The exhaust outlet connects sequentially to the tailpipe via branch line two of the humidifier and the tailpipe throttle. The controller output is connected to the control terminals of the air compressor and the tailpipe throttle.

[0080] Preferably, the air control subsystem further includes a flow meter and an electrically controlled three-way valve. The flow meter is located at the air compressor inlet to obtain the gas flow rate entering the air compressor and send it to the controller. The electrically controlled three-way valve is located between the air compressor and the intercooler; its input end is connected to the air compressor output end, one output end is connected to the intercooler, another output end is connected to the exhaust pipe, and its control end is connected to the controller output end.

[0081] The hydrogen control subsystem further includes a hydrogen source, a pressure reducing valve, a shut-off valve, an ejector, a water distributor, a near-end drain valve (i.e., a drain control valve close to the hydrogen control subsystem), and an exhaust valve. Specifically, the ejector's jet inlet connects to the hydrogen source sequentially via the shut-off valve and the pressure reducing valve; its jet inlet connects to the outlet of the water distributor; and its outlet connects to the hydrogen inlet of the fuel cell stack. The water distributor's inlet connects to the hydrogen tail gas outlet of the fuel cell stack; its outlet connects to the tail gas outlet via the near-end drain valve; and its outlet also connects to the tail gas outlet via the exhaust valve.

[0082] A liquid level sensor is installed inside the cavity of the water distributor to obtain the liquid level height inside the water distributor in real time and send it to the controller.

[0083] The controller's output is connected to the control terminals of the pressure reducing valve, shut-off valve, near-end drain valve, and exhaust valve.

[0084] Preferably, the hydrogen control subsystem further includes a safety valve, a switching valve, and a hydrogen circulation pump. The safety valve is located between the pressure reducing valve and the shut-off valve, and is integrated with the pressure reducing valve. The outlet of the water distribution unit is connected to the hydrogen inlet of the fuel cell stack via the switching valve and the hydrogen circulation pump in sequence.

[0085] The controller's output is also connected to the control terminals of the safety valve, switching valve, and hydrogen circulation pump.

[0086] Preferably, the hydrogen control subsystem further includes a main proportional valve and a bypass proportional valve. One output of the shut-off valve is connected to the hydrogen inlet of the fuel cell stack via the main proportional valve and the ejector, while the other output is connected to the hydrogen inlet of the fuel cell stack via the bypass proportional valve.

[0087] The plate heat exchanger is located at the front end of the shut-off valve. Its input end is connected to the safety valve, and its output end is connected to the ejector's jet inlet via the shut-off valve and the main proportional valve in sequence.

[0088] Preferably, the hydrogen control subsystem further includes a remote drain valve (i.e., a drain control valve located away from the hydrogen control subsystem). Furthermore, a drain outlet is located at the bottom opposite to the hydrogen control subsystem of the fuel cell stack, and this drain outlet is connected to the tailpipe via the remote drain valve.

[0089] Preferably, the hydrogen control subsystem further includes a first pressure sensor P1, a second pressure sensor P2, and a third pressure sensor P3. The first pressure sensor P1 is located at the output of the shut-off valve and is a high-pressure sensor; the second pressure sensor P2 is located at the output of the main proportional valve and is a medium-pressure sensor; and the third pressure sensor P3 is located at the hydrogen inlet of the fuel cell stack and is a low-pressure sensor.

[0090] The controller is also used to display real-time data from the aforementioned liquid level sensor, first pressure sensor P1, second pressure sensor P2, and third pressure sensor P3.

[0091] The various embodiments of the present invention have been described above. These descriptions are exemplary and not exhaustive, nor are they limited to the disclosed embodiments. Many modifications and variations will be apparent to those skilled in the art without departing from the scope and spirit of the described embodiments. The terminology used herein is chosen to best explain the principles, practical applications, or improvements to the prior art of the embodiments, or to enable others skilled in the art to understand the embodiments disclosed herein.

Claims

1. An adaptive nitrogen emission control method for fuel cells, characterized in that, Includes the following steps: S1. Determine the hydrogen concentration change curves in the hydrogen chamber of the fuel cell under different environmental pressures and temperatures and after being shut down and left to stand for different times. S2. When the fuel cell is powered on this time, obtain the last shutdown time of the fuel cell, the ambient pressure, and the ambient temperature. Combine this with the hydrogen concentration change curve in the hydrogen chamber mentioned above to predict the hydrogen concentration in the hydrogen chamber of the fuel cell at the current moment. S3. Identify whether the predicted hydrogen concentration in the hydrogen chamber of the fuel cell is lower than the target concentration; when the hydrogen concentration is lower than the target concentration, control the fuel cell system to not perform nitrogen purging during startup; when the hydrogen concentration is higher than the target concentration, further determine the nitrogen purging time based on the predicted hydrogen concentration in the hydrogen chamber of the fuel cell, and control the fuel cell system to perform the nitrogen purging operation for that time during startup.

2. The adaptive nitrogen emission control method for fuel cells according to claim 1, characterized in that, Step S1 further includes: S11. The hydrogen concentration change curves in the hydrogen chamber of the fuel cell were determined by experiment under different environmental pressures and temperatures and after being shut down and left to stand for different times. S12. Upload the hydrogen concentration change curves in the hydrogen chamber of the fuel cell under different environmental pressures and temperatures and after being shut down and left to stand for different times to the cloud platform for storage.

3. The adaptive nitrogen emission control method for fuel cells according to claim 2, characterized in that, Step S2 further includes: S21. Each time the fuel cell is shut down, its shutdown time is uploaded to the cloud platform for storage; S22. When the fuel cell is powered on this time, the fuel cell system sends a command to the cloud platform to obtain the last shutdown time, obtains the last shutdown time of the fuel cell, and then determines the resting time; S23. Obtain the current ambient pressure and ambient temperature. The fuel cell system continues to send instructions to the cloud platform to obtain the hydrogen concentration change curve in the hydrogen chamber that matches the current ambient temperature and ambient temperature. Obtain the corresponding hydrogen concentration change curve in the hydrogen chamber. S24. Based on the obtained hydrogen concentration change curve in the hydrogen chamber and the settling time, the predicted value of the hydrogen concentration in the fuel cell hydrogen chamber at the current moment is obtained.

4. A fuel cell system with adaptive nitrogen removal function, characterized in that, The system includes a controller for performing the method according to any one of claims 1-3, and further includes a fuel cell stack, an air control subsystem, a hydrogen control subsystem, a coolant control subsystem, and a tailpipe; wherein, The coolant regulation subsystem further includes a radiator, a heater, and a thermostat; wherein, the input end of the thermostat is connected to the coolant outlet of the fuel cell stack, the output end of the thermostat is connected to the coolant inlet of the fuel cell stack via the radiator, and the output end of the thermostat is connected to the coolant inlet of the fuel cell stack via the heater. The controller is also used to control the operation of the air conditioning subsystem, hydrogen conditioning subsystem, and coolant conditioning subsystem to complete the startup, operation, and shutdown of the fuel cell system.

5. The fuel cell system according to claim 4, characterized in that, The air conditioning subsystem further includes an air compressor, intercooler, humidifier, and exhaust throttle valve; among which, The air inlet of the fuel cell stack is connected to the output end of the air compressor via the first branch of the humidifier and the intercooler in sequence. The air outlet of the fuel cell stack is connected to the tail exhaust via the second branch of the humidifier and the tail exhaust throttle valve in sequence. The controller's output is connected to the control terminals of the air compressor and the exhaust throttle valve.

6. The fuel cell system according to claim 5, characterized in that, The air control subsystem also includes a flow meter and an electrically controlled three-way valve; among which, The flow meter is installed at the air inlet of the air compressor to obtain the flow rate of gas entering the air compressor and send it to the controller; The electrically controlled three-way valve is located between the air compressor and the intercooler. The input end of the electrically controlled three-way valve is connected to the output end of the air compressor, the first output end of the electrically controlled three-way valve is connected to the intercooler, the second output end of the electrically controlled three-way valve is connected to the tail exhaust, and the control end of the electrically controlled three-way valve is connected to the output end of the controller.

7. The fuel cell system according to claim 6, characterized in that, The hydrogen control subsystem further includes a hydrogen source, a pressure reducing valve, a shut-off valve, an ejector, a water distribution unit, a near-end drain valve, and an exhaust valve; among which, The ejector's jet inlet is connected to the hydrogen source via a shut-off valve and a pressure reducing valve. The ejector's duct inlet is connected to the outlet of the water distribution unit. The ejector's confluence outlet is connected to the hydrogen inlet of the fuel cell stack. The water distribution unit's inlet is connected to the hydrogen tail gas outlet of the fuel cell stack. The water distribution unit's outlet is connected to the tail drain via a near-end drain valve. The water distribution unit's outlet is also connected to the tail drain via an exhaust valve. A liquid level sensor is installed inside the cavity of the water distribution component to obtain the liquid level height inside the water distribution component in real time and send it to the controller; The controller's output is connected to the control terminals of the pressure reducing valve, shut-off valve, near-end drain valve, and exhaust valve.

8. The fuel cell system according to claim 7, characterized in that, The hydrogen control subsystem also includes safety valves, on / off valves, and a hydrogen circulation pump; among which, The safety valve is located between the pressure reducing valve and the shut-off valve, and is integrated with the pressure reducing valve. The outlet of the water distribution unit is connected to the hydrogen inlet of the fuel cell stack via a switch valve and a hydrogen circulation pump in sequence. The controller's output is also connected to the control terminals of the safety valve, switching valve, and hydrogen circulation pump.

9. The fuel cell system according to claim 8, characterized in that, The hydrogen control subsystem also includes a main proportional valve, a bypass proportional valve, and a plate heat exchanger; among which, One output of the shut-off valve is connected to the hydrogen inlet of the fuel cell stack via the main proportional valve and ejector in sequence, and the other output is connected to the hydrogen inlet of the fuel cell stack via the bypass proportional valve. The plate heat exchanger is located at the front end of the shut-off valve. The input end of the plate heat exchanger is connected to the safety valve, and the output end of the plate heat exchanger is connected to the jet inlet of the ejector in sequence through the shut-off valve and the main proportional valve.

10. The fuel cell system according to claim 9, characterized in that, The hydrogen control subsystem also includes a remote drain valve; and, A drain outlet is located at the bottom opposite to the hydrogen control subsystem of the fuel cell stack. This drain outlet is connected to the tail drain via a remote drain valve.

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