A method for controlling intake air humidity of a fuel cell

Abstract

The present invention provides an intake humidity control device for a fuel cell, belonging to the field of fuel cell technology, and solves the problem in the prior art that the humidity control effect is easily affected by usage conditions or equipment attenuation. The device includes flow control valves 1 and 2, intercoolers 1 and 2, a temperature control device, a humidifier, and a controller. The air inlet of the fuel cell stack is connected to the output end of the intake device via intercooler 1, the dry area of ​​the humidifier, and intercooler 2 in sequence; the input end of flow control valve 1 is connected to the coolant outlet of the fuel cell stack and the coolant outlets of intercoolers 1 and 2 respectively, the output end 1 is connected to the input end of flow control valve 2 via the temperature control device, and the output end 2 is connected to the coolant inlet of intercooler 2; the output end 1 of flow control valve 2 is connected to the coolant inlet of the fuel cell stack, and the output end 2 is connected to the coolant inlet of intercooler 1. The humidity of the gas entering the stack is adjusted by temperature control of the two-stage intercooler, effectively improving the environmental adaptability and the service life of the fuel cell stack.

Description

Technical Field

[0001] The present invention relates to the technical field of fuel cells, and in particular to a method for controlling intake humidity of a fuel cell. Background Art

[0002] The proton exchange membrane of the fuel cell needs to be humidified under appropriate conditions to achieve good working performance. The air and hydrogen intake of the fuel cell need to be humidified to prevent the proton exchange membrane from dehydrating during operation, which will reduce performance and working life.

[0003] At present, fuel cell systems are usually equipped with humidifiers to solve the problem of air path humidification. Currently, the humidity can be reduced by increasing the total air flow entering the humidifier, and the excess air required by the fuel cell stack leaves the engine through the tail exhaust.

[0004] The operating point of a fuel cell system can shift depending on usage conditions or degradation. When the stack becomes dry, it can affect stack performance, reliability, and durability. Therefore, the fuel cell system needs to have a humidity control function. Summary of the Invention

[0005] The embodiment of the present invention aims to provide a method for controlling the intake humidity of a fuel cell to solve the existing problems.

[0006] On the one hand, an embodiment of the present invention provides an intake humidity control device for a fuel cell, comprising flow control valves 1 and 2, intercoolers 1 and 2, a temperature control device, a humidifier, and a controller; wherein,

[0007] The air inlet of the fuel cell stack is connected to the output end of the air intake device in sequence through intercooler 1, the dry area of ​​the humidifier, and intercooler 2; the input end of flow control valve 1 is connected to the coolant outlet of the fuel cell stack and the coolant outlets of intercoolers 1 and 2 respectively, output end 1 is connected to the input end of flow control valve 2 through the temperature control device, and output end 2 is connected to the coolant inlet of intercooler 2; output end 1 of flow control valve 2 is connected to the coolant inlet of the fuel cell stack, and output end 2 is connected to the coolant inlet of intercooler 1;

[0008] The controller is used to monitor the humidity of the gas entering the stack in real time and determine whether it is within the preset range; if so, maintain the openings of flow control valves one and two unchanged; if the humidity of the gas entering the stack is lower than the lower limit threshold of the preset range, adjust the openings of flow control valves one and two in real time according to the humidity of the gas entering the stack and the threshold of the preset range, and judge again until the humidity of the gas entering the stack reaches the preset range, ending the humidity control.

[0009] The above technical solution has the following beneficial effects: Humidity is regulated by a two-stage intercooler. Intercooler 2 maintains the temperature of the gas entering the humidifier, while intercooler 1 maintains the temperature of the gas entering the fuel cell stack. This double cooling process effectively improves environmental adaptability. This device can meet the fuel cell stack humidification requirements in various environments, ensuring the operational stability, reliability, and durability of the fuel cell stack.

[0010] Based on the further improvement of the above device, the air intake equipment includes at least one of an air compressor and a hydrogen injection device, each of which is connected to a corresponding independent air intake humidity control device.

[0011] The beneficial effect of the above-mentioned improvement scheme is that the humidity of the air and hydrogen entering the stack can be adjusted separately through the independent air intake humidity control device, thereby improving the environmental adaptability.

[0012] The device also includes an intake throttle valve and an exhaust throttle valve; wherein,

[0013] The inlet of the air intake throttle valve is connected to the outlet of the intercooler 1, the outlet is connected to the air inlet of the fuel cell stack, and the control end is connected to the output end of the controller;

[0014] The inlet of the tail gas throttle valve is connected to the exhaust port of the fuel cell stack, the outlet is connected to the wet zone inlet of the humidifier, and the control end is connected to the output end of the controller.

[0015] The beneficial effect of the above-mentioned improvement scheme is that after adding the intake throttle valve and the exhaust throttle valve, a safe sealed environment can be formed inside the fuel cell stack when the fuel cell is shut down.

[0016] The controller further comprises:

[0017] The data acquisition unit is used to obtain the temperature of the gas entering the reactor, the humidity of the gas entering the reactor, and the actual temperature of the gas entering the humidifier in real time, and send them to the data processing and control unit;

[0018] The data processing and control unit is used to monitor the humidity of the gas entering the stack in real time and determine whether it is within a preset range; if so, maintain the openings of flow control valves 1 and 2 unchanged; if the humidity of the gas entering the stack is lower than the lower limit threshold of the preset range, obtain the difference between the humidity of the gas entering the stack and the preset value within the preset range, and adjust the opening of flow control valve 1 according to the difference. After the adjustment is completed, the opening of flow control valve 2 is adjusted in real time according to the current temperature of the gas entering the stack so that the temperature of the gas entering the stack reaches the preset rated temperature, and the judgment is repeated until the humidity of the gas entering the stack reaches the preset range, and the humidity control is terminated.

[0019] The beneficial effect of the above improvement scheme is that the temperature of the gas may change after passing through the humidifier. The adaptability of the gas humidity to the environment is related to the temperature. Through two-stage temperature control, the stability of the humidity of the gas entering the stack can be effectively guaranteed, thereby improving the service life of the fuel cell.

[0020] The data acquisition unit further comprises:

[0021] Temperature sensor 1, installed on the inner wall of the outlet pipe of the air inlet throttle valve, is used to collect the temperature of the gas entering the reactor in real time;

[0022] Temperature sensor 2 is installed on the inner wall of the dry area inlet pipe of the humidifier to collect the actual temperature of the gas entering the humidifier in real time;

[0023] The humidity sensor is installed on the inner wall of the outlet pipe of the air inlet throttle valve and is used to collect the humidity of the gas entering the stack in real time.

[0024] The beneficial effect of the above improvement scheme is that the temperature of the gas entering the stack, the humidity of the gas entering the stack, and the actual temperature of the gas entering the humidifier can be obtained through the above data acquisition unit. Combined with the corresponding humidity control method, the gas entering the stack can be prevented from being too wet or too dry.

[0025] The data processing and control unit executes the following procedures:

[0026] Monitor the current humidity of the incoming gas to determine whether it is within the preset range. If so, maintain the openings of flow control valves 1 and 2 unchanged. If the humidity is below the lower limit of the preset range, proceed to the next step.

[0027] Obtain the average of the upper threshold and the lower threshold of the preset range as the preset value;

[0028] Obtaining the difference ΔR between the humidity of the gas entering the stack and a preset value, inputting the difference ΔR into a preset temperature rise model to obtain a theoretical temperature rise ΔT of the gas in the humidifier;

[0029] Obtaining the actual temperature of the gas entering the humidifier, and determining the theoretical temperature T1 of the gas at the dry zone inlet of the humidifier based on the sum of the actual temperature and the theoretical temperature rise ΔT of the gas;

[0030] Adjust the opening of the flow regulating valve 1 until the actual temperature of the gas entering the humidifier reaches the theoretical temperature T1, and then end the adjustment of the flow regulating valve 1;

[0031] The opening of flow control valve 1 is controlled to remain unchanged, the temperature of the incoming gas at the end of adjustment is obtained, and the opening of flow control valve 2 is adjusted until the incoming gas temperature reaches the preset rated temperature, thereby completing the adjustment of flow control valve 2;

[0032] It is determined again whether the humidity of the gas entering the stack is within the preset range, and the humidity control is terminated until the humidity of the gas entering the stack reaches the preset range.

[0033] The beneficial effects of this further improvement are as follows: Intercooler 2 is installed at the front end of the humidifier to regulate the temperature of the gas entering the humidifier by dissipating heat, thereby achieving the required humidity for the stack. Intercooler 1 and a flow control valve (flow control valve 2) are installed at the rear end of the humidifier to control the temperature of the gas after passing through the intercooler. The openings of flow control valves 1 and 2 can be adjusted in real time based on the current humidity level of the fuel cell stack to change the humidity entering the stack and meet the humidification requirements.

[0034] Furthermore, the preset range is the range of the humidity of the gas entering the stack within which the stack meets the maximum power requirement of the vehicle and the service life is longer than the rated life.

[0035] The beneficial effect of the above-mentioned further improvement scheme is that the humidity range for regulation is limited, and within this range the maximum power demand limit of the vehicle can be guaranteed and the life of the battery stack can be guaranteed to be above the rated life.

[0036] Furthermore, the lower limit threshold of the preset range is higher than the dew point of the current temperature.

[0037] The beneficial effect of the above-mentioned further improvement scheme is to prevent liquid water from entering the stack and affecting the performance of the stack.

[0038] Furthermore, it also includes a three-way valve and one-way control valves 1 and 2; wherein,

[0039] The input end of the three-way valve is connected to the exhaust port of the fuel cell stack, the output end 1 is connected to the wet zone inlet of the humidifier through the one-way control valve 1, and the output end 2 is connected to the inlet of the one-way control valve 2; the control ends of the one-way control valves 1 and 2 are connected to the output end of the controller;

[0040] The controller is also used to control the opening of the one-way control valve 1 to decrease and the opening of the one-way control valve 2 to increase when the humidity of the gas entering the stack is higher than the upper limit threshold of the preset range; and to control the opening of the one-way control valve 1 to increase and the opening of the one-way control valve 2 to decrease when the humidity of the gas entering the stack is lower than the lower limit threshold of the preset range.

[0041] The beneficial effect of the above further improvement scheme is that after adding the three-way valve and the one-way control valves 1 and 2, the over-humidity control is increased, making the humidity control of the gas entering the stack more rapid and reliable.

[0042] On the other hand, an embodiment of the present invention provides a method for controlling humidity using the above-mentioned intake air humidity control device, comprising the following steps:

[0043] Real-time monitoring of the humidity of the incoming gas to determine whether it is within the preset range;

[0044] If yes, keep the opening of flow control valves 1 and 2 unchanged;

[0045] If the humidity of the gas entering the stack is lower than the lower limit threshold of the preset range, the openings of flow control valves one and two are adjusted in real time according to the humidity of the gas entering the stack and the threshold of the preset range, and the judgment is made again until the humidity of the gas entering the stack reaches the preset range and the humidity control is ended.

[0046] The beneficial effect of this technical solution is that humidity is regulated by two intercoolers: intercooler 2 maintains the temperature of the gas entering the humidifier, and intercooler 1 maintains the temperature of the gas entering the fuel cell stack. This double cooling process effectively improves environmental adaptability. This device can meet the fuel cell stack humidification requirements in various environments, ensuring the operational stability, reliability, and durability of the fuel cell stack.

[0047] This Summary is provided to introduce a selection of concepts in a simplified form that are further described below in the Detailed Description. This Summary is not intended to identify key features or essential features of the disclosure, nor is it intended to limit the scope of the disclosure. BRIEF DESCRIPTION OF THE DRAWINGS

[0048] The above and other objects, features and advantages of the present disclosure will become more apparent through a more detailed description of exemplary embodiments of the present disclosure with reference to the accompanying drawings, wherein like reference numerals generally represent like components throughout the exemplary embodiments of the present disclosure.

[0049] Figure 1 A schematic diagram of the composition of the intake air humidity control device of Example 1 is shown;

[0050] Figure 2 A schematic diagram of the use of the intake air humidity control device of Example 1 is shown;

[0051] Figure 3 A schematic diagram of the composition of the intake air humidity control device according to embodiment 2 is shown;

[0052] Figure 4 A schematic diagram of the system architecture of the intake air humidity control device of Example 2 is shown.

[0053] Figure markings: flow control valve 1; 2-flow control valve 2; 3-humidity sensor; 4-intercooler 1; 5-temperature sensor 1; 6-humidifier; 7-temperature sensor 2; 8-intercooler 2; 9-air compressor; 10-fuel cell stack. DETAILED DESCRIPTION

[0054] Embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. Although embodiments of the present disclosure are shown in the accompanying drawings, it should be understood that the present disclosure can be implemented in various forms and should not be limited by the embodiments set forth herein. Rather, these embodiments are provided to make the present disclosure more thorough and complete, and to fully convey the scope of the present disclosure to those skilled in the art.

[0055] As used herein, the term "including" and its variations represent open inclusion, i.e., "including but not limited to." Unless otherwise stated, the term "or" means "and / or." The term "based on" means "based at least in part on." The terms "an example embodiment" and "an 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.

[0056] Example 1

[0057] One embodiment of the present invention discloses a method for controlling the intake humidity of a fuel cell, comprising flow regulating valves 1 and 2, intercoolers 1 and 2, a temperature control device, a humidifier, and a controller; wherein,

[0058] The air inlet of the fuel cell stack (which can be a hydrogen inlet or an air inlet) is connected to the output end of the air intake device in sequence through intercooler 1, the dry area of ​​the humidifier, and intercooler 2; the input end of flow regulating valve 1 is connected to the coolant outlet of the fuel cell stack and the coolant outlets of intercoolers 1 and 2 respectively, output end 1 is connected to the input end of flow regulating valve 2 through the temperature control device, and output end 2 is connected to the coolant inlet of intercooler 2; output end 1 of flow regulating valve 2 is connected to the coolant inlet of the fuel cell stack, and output end 2 is connected to the coolant inlet of intercooler 1.

[0059] The controller is used to monitor the humidity of the gas entering the stack in real time and determine whether it is within the preset range; if so, maintain the openings of flow control valves one and two unchanged; if the humidity of the gas entering the stack is lower than the lower limit threshold of the preset range, adjust the openings of flow control valves one and two in real time according to the humidity of the gas entering the stack and the threshold of the preset range, and judge again until the humidity of the gas entering the stack reaches the preset range, ending the humidity control.

[0060] Preferably, the air intake device includes at least one of an air compressor and a hydrogen injection device, which are respectively connected to the corresponding independent air intake humidity control device and then connected to the corresponding air inlet or hydrogen inlet of the fuel cell stack, such as Figure 2 shown.

[0061] Optionally, the openings of flow control valves one and two can be obtained using a pre-trained deep learning network, the input of which is the humidity of the gas entering the stack, the upper threshold of a preset range, and the lower threshold of the preset range, and the output is the openings of flow control valves one and two; alternatively, the method described in Example 2 can be used to obtain the openings.

[0062] In implementation, using an air compressor as an example, after the air is heated by the compressor, intercooler 2 controls the air temperature entering the humidifier, while intercooler 1 controls the air temperature entering the reactor. This two-stage temperature change regulates the amount of humidification to ensure that the required humidity is met before entering the reactor. The inlet humidity control device for the hydrogen injection system uses the same control method as the air compressor.

[0063] Compared to existing technologies, the device provided in this embodiment regulates humidity through a two-stage intercooler. Intercooler 2 maintains the temperature of the gas entering the humidifier, while intercooler 1 maintains the temperature of the gas entering the fuel cell stack. This dual-stage cooling system effectively improves humidity control and adaptability to various environmental conditions. This device can meet fuel cell stack humidification requirements in various environments, ensuring operational stability, reliability, and durability of the fuel cell stack.

[0064] Example 2

[0065] Based on the improvement of Example 1, the intake humidity control device further includes an intake throttle valve and an exhaust throttle valve.

[0066] Among them, the inlet of the intake throttle valve is connected to the outlet of the intercooler, and the outlet is connected to the air inlet of the fuel cell stack. Figures 3-4 As shown, the control end is connected to the output end of the controller; the inlet of the tail gas throttle valve is connected to the exhaust port of the fuel cell stack, the outlet is connected to the wet zone inlet of the humidifier, and the control end is connected to the output end of the controller.

[0067] The use of intake throttle valves and exhaust throttle valves enables a safe sealed environment to be formed inside the fuel cell stack when the fuel cell is shut down.

[0068] Preferably, the controller further comprises a data acquisition unit and a data processing and control unit which are connected in sequence.

[0069] The data acquisition unit is used to obtain the temperature of the gas entering the stack, the humidity of the gas entering the stack, and the actual temperature of the gas entering the humidifier in real time, and send them to the data processing and control unit.

[0070] The data processing and control unit is used to monitor the humidity of the gas entering the stack in real time and determine whether it is within a preset range; if so, maintain the openings of flow control valves 1 and 2 unchanged; if the humidity of the gas entering the stack is lower than the lower limit threshold of the preset range, obtain the difference between the humidity of the gas entering the stack and the preset value within the preset range, and adjust the opening of flow control valve 1 according to the difference. After the adjustment is completed, the opening of flow control valve 2 is adjusted in real time according to the current temperature of the gas entering the stack so that the temperature of the gas entering the stack reaches the preset rated temperature, and the judgment is repeated until the humidity of the gas entering the stack reaches the preset range, and the humidity control is terminated.

[0071] Specifically, the temperature of the gas may change after passing through the humidifier. The adaptability of the gas humidity to the environment is related to the temperature. Through two-stage temperature control, the stability of the humidity of the gas entering the stack can be effectively guaranteed, thereby improving the service life of the fuel cell.

[0072] Preferably, the data acquisition unit further includes temperature sensors 1 and 2, and a humidity sensor, such as Figure 4 shown.

[0073] Temperature sensor 1 is installed on the inner wall of the outlet pipe of the air intake throttle valve and is used to collect the temperature of the gas entering the reactor in real time.

[0074] Temperature sensor 2 is installed on the inner wall of the dry area inlet pipe of the humidifier and is used to collect the actual temperature of the gas entering the humidifier in real time.

[0075] The humidity sensor is installed on the inner wall of the outlet pipe of the air inlet throttle valve and is used to collect the humidity of the gas entering the stack in real time.

[0076] Preferably, the data processing and control unit executes the following program:

[0077] S1. Monitor the current humidity of the incoming gas to determine whether it is within a preset range. If so, maintain the openings of flow control valves 1 and 2 unchanged. If the humidity is below the lower threshold of the preset range (too dry), proceed to the next step.

[0078] S2. Get the average of the upper and lower thresholds of the preset range as the preset value;

[0079] S3. Obtain the difference ΔR between the humidity of the incoming gas and a preset value, and input this difference ΔR into a preset temperature rise model to derive a theoretical temperature rise ΔT of the gas in the humidifier. Specifically, this temperature rise model can be obtained by calibration, for example, using a trained vector machine or deep learning network, where the input is ΔR and the output is ΔT, as will be understood by those skilled in the art.

[0080] S4. Get the actual temperature of the gas entering the humidifier, and determine the theoretical temperature T1 of the gas at the dry zone inlet of the humidifier based on the sum of the actual temperature and the theoretical temperature rise ΔT of the gas

[0081] T1 = actual temperature + ΔT;

[0082] S5. Adjust the opening of the flow control valve 1 until the actual temperature of the gas entering the humidifier reaches the theoretical temperature T1, and then end the adjustment of the flow control valve 1; specifically, when ΔT is greater than 0, the coolant flow rate entering the intercooler 2 is reduced, and when ΔT is less than 0, the coolant flow rate entering the intercooler 2 is increased;

[0083] S6. Maintain the opening of flow control valve 1, obtain the incoming gas temperature at the end of adjustment, and adjust the opening of flow control valve 2 until the incoming gas temperature reaches the preset rated temperature, thereby ending adjustment of flow control valve 2. Specifically, when the incoming gas temperature exceeds the preset rated temperature, the coolant flow rate entering intercooler 2 is increased; when the incoming gas temperature falls below the preset rated temperature, the coolant flow rate entering intercooler 2 is decreased.

[0084] S7. Determine again whether the humidity of the gas entering the stack is within the preset range. Humidity control is terminated until the humidity of the gas entering the stack reaches the preset range.

[0085] Preferably, the preset range is the range of the humidity of the gas entering the stack within which the stack meets the maximum power requirement of the vehicle and has a service life exceeding the rated life. This range can be obtained through calibration.

[0086] Preferably, the lower limit threshold of the preset range should also be higher than the dew point of the current temperature.

[0087] Preferably, the intake air humidity control device further includes a three-way valve and one and two one-way control valves.

[0088] Among them, the input end of the three-way valve is connected to the exhaust port of the fuel cell stack, the output end 1 is connected to the wet zone inlet of the humidifier through the one-way control valve 1, and the output end 2 is connected to the inlet of the one-way control valve 2; the control ends of the one-way control valves 1 and 2 are connected to the output end of the controller.

[0089] Preferably, the controller is further configured to control the opening of the one-way control valve 1 to decrease and the opening of the one-way control valve 2 to increase when the humidity of the gas entering the stack is higher than the upper limit threshold of the preset range; and to control the opening of the one-way control valve 1 to increase and the opening of the one-way control valve 2 to decrease when the humidity of the gas entering the stack is lower than the lower limit threshold of the preset range, and then execute the above steps S1 to S7.

[0090] Preferably, when the air humidity needs to be increased, the one-way control valve 2 can be directly closed, and the air humidity can be increased by adjusting the opening of the one-way control valve 1 alone.

[0091] Compared with the embodiment, this embodiment has the following beneficial effects:

[0092] 1. An intercooler 2 is set at the front end of the humidifier to adjust the temperature of the gas entering the humidifier by adjusting the heat dissipation, thereby achieving the requirement of adjusting the humidity entering the pile.

[0093] 2. An intercooler and a flow control valve (flow control valve 2) are installed at the rear end of the humidifier to control the temperature of the gas after passing through the intercooler.

[0094] 3. The opening of flow control valves 1 and 2 can be adjusted in real time according to the current humidity status of the fuel cell stack to change the humidity entering the stack to meet the humidification requirements.

[0095] Example 3

[0096] Another embodiment of the present invention discloses a method for controlling humidity using the intake air humidity control device described in embodiment 1 or 2, comprising the following steps:

[0097] SS1. Real-time monitoring of the humidity of the incoming gas to determine whether it is within the preset range;

[0098] SS2. If yes, maintain the opening of flow control valves 1 and 2 unchanged;

[0099] SS3. If the humidity of the incoming gas is lower than the lower limit of the preset range, adjust the openings of flow control valves 1 and 2 in real time based on the humidity of the incoming gas and the threshold of the preset range. Repeat the judgment until the humidity of the incoming gas reaches the preset range and the humidity control ends.

[0100] Compared to existing technologies, the device provided in this embodiment regulates humidity through a two-stage intercooler. Intercooler 2 maintains the temperature of the gas entering the humidifier, while intercooler 1 maintains the temperature of the gas entering the fuel cell stack. This dual-stage cooling system effectively improves humidity control and adaptability to various environmental conditions. This device can meet fuel cell stack humidification requirements in various environments, ensuring operational stability, reliability, and durability of the fuel cell stack.

[0101] While various embodiments of the present disclosure have been described above, the foregoing description is intended to be illustrative, non-exhaustive, and not 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 selected to best explain the principles of the embodiments, their practical applications, or improvements over the prior art, or to enable others skilled in the art to understand the embodiments disclosed herein.

Claims

1. A method for controlling intake humidity of a fuel cell, characterized in that: Including flow control valves 1 and 2, intercoolers 1 and 2, temperature control equipment, humidifier, and controller; Among them, The air inlet of the fuel cell stack is connected to the output end of the air intake device in sequence through intercooler 1, the dry area of ​​the humidifier, and intercooler 2; the input end of flow control valve 1 is connected to the coolant outlet of the fuel cell stack and the coolant outlets of intercoolers 1 and 2 respectively, output end 1 is connected to the input end of flow control valve 2 through the temperature control device, and output end 2 is connected to the coolant inlet of intercooler 2; output end 1 of flow control valve 2 is connected to the coolant inlet of the fuel cell stack, and output end 2 is connected to the coolant inlet of intercooler 1; The controller is used to monitor the humidity of the incoming gas in real time and determine whether it is within a preset range. If so, the openings of flow control valves 1 and 2 are maintained unchanged. If the humidity of the incoming gas is below the lower threshold of the preset range, the openings of flow control valves 1 and 2 are adjusted in real time based on the humidity of the incoming gas and the threshold of the preset range. The controller repeats the monitoring until the humidity of the incoming gas reaches the preset range, ending humidity control. The air intake device includes at least one of an air compressor and a hydrogen injection device, each of which is connected to an air intake humidity control device of a corresponding independent fuel cell; It also includes an intake throttle valve and an exhaust throttle valve; wherein, The inlet of the air intake throttle valve is connected to the outlet of the intercooler 1, the outlet is connected to the air inlet of the fuel cell stack, and the control end is connected to the output end of the controller; The inlet of the tail gas throttle valve is connected to the exhaust port of the fuel cell stack, the outlet is connected to the wet zone inlet of the humidifier, and the control end is connected to the output end of the controller; The controller further comprises: The data acquisition unit is used to obtain the temperature of the gas entering the reactor, the humidity of the gas entering the reactor, and the actual temperature of the gas entering the humidifier in real time, and send them to the data processing and control unit; The data processing and control unit is configured to monitor the humidity of the incoming gas in real time and determine whether it is within a preset range. If so, the openings of flow control valves 1 and 2 are maintained unchanged. If the humidity of the incoming gas is below a lower threshold of the preset range, the difference between the humidity of the incoming gas and a preset value within the preset range is obtained, and the opening of flow control valve 1 is adjusted based on the difference. After the adjustment is completed, the opening of flow control valve 2 is adjusted in real time based on the current temperature of the incoming gas, so that the incoming gas temperature reaches a preset rated temperature. The humidity control is terminated by repeating the determination until the humidity of the incoming gas reaches the preset range. The data acquisition unit further comprises: Temperature sensor 1, installed on the inner wall of the outlet pipe of the air inlet throttle valve, is used to collect the temperature of the gas entering the reactor in real time; Temperature sensor 2 is installed on the inner wall of the dry area inlet pipe of the humidifier to collect the actual temperature of the gas entering the humidifier in real time; A humidity sensor is installed on the inner wall of the outlet pipe of the air inlet throttle valve to collect the humidity of the incoming gas in real time; The data processing and control unit executes the following procedures: Monitor the current humidity of the incoming gas to determine whether it is within a preset range. If so, maintain the openings of flow control valves 1 and 2 unchanged. If the humidity is below the lower threshold of the preset range, proceed to the next step. Obtain the average of the upper threshold and the lower threshold of the preset range as the preset value; Get the difference Δ between the humidity of the gas entering the pile and the preset value R , the difference Δ R Input the preset temperature rise model to obtain the theoretical temperature rise of the humidifier gas Δ T ; Get the actual temperature of the gas entering the humidifier, and calculate the actual temperature and the theoretical temperature rise of the gas Δ T Addition operation ， Determine the theoretical gas temperature at the dry zone inlet of the humidifier T 1; Adjust the opening of the flow control valve until the actual temperature of the gas entering the humidifier reaches the theoretical temperature. T 1. Complete the adjustment of flow control valve 1; The opening of flow control valve 1 is controlled to remain unchanged, the temperature of the incoming gas at the end of adjustment is obtained, and the opening of flow control valve 2 is adjusted until the incoming gas temperature reaches the preset rated temperature, thereby completing the adjustment of flow control valve 2; It is determined again whether the humidity of the gas entering the stack is within the preset range, and the humidity control is terminated until the humidity of the gas entering the stack reaches the preset range.

2. The method for controlling intake air humidity of a fuel cell according to claim 1, wherein: The preset range is the range of the humidity of the gas entering the stack within which the stack meets the maximum power requirement of the vehicle and the service life is longer than the rated life.

3. The method for controlling intake air humidity of a fuel cell according to claim 2, wherein: The lower limit threshold of the preset range is higher than the dew point of the current temperature.

4. The method for controlling intake air humidity of a fuel cell according to claim 3, wherein: It also includes a three-way valve and one-way control valves 1 and 2; wherein, The input end of the three-way valve is connected to the exhaust port of the fuel cell stack, the output end 1 is connected to the wet zone inlet of the humidifier through the one-way control valve 1, and the output end 2 is connected to the inlet of the one-way control valve 2; the control ends of the one-way control valves 1 and 2 are connected to the output end of the controller; The controller is also used to control the opening of the one-way control valve 1 to decrease and the opening of the one-way control valve 2 to increase when the humidity of the gas entering the stack is higher than the upper limit threshold of the preset range; and to control the opening of the one-way control valve 1 to increase and the opening of the one-way control valve 2 to decrease when the humidity of the gas entering the stack is lower than the lower limit threshold of the preset range.

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