Fuel cell drain valve control method, fuel cell system and storage medium

Abstract

The invention discloses a control method for a drain valve of a fuel cell. S1, acquiring a current integral average value Q0 at the optimal opening time of the drain valve; s2, acquiring a hydrogen outlet pressure difference integral value D0 at the optimal closing time of the drain valve; s3, calculating an air pressure correction coefficient; and S4, when the set conditions are met, a drainage valve is controlled to be opened and closed, and a drainage period is completed. According to the control method for the drain valve of the fuel cell, the control accuracy of the opening time of the drain valve is improved, and leakage of hydrogen from the drain valve is reduced, so that the hydrogen consumption rate of a system is reduced, frequent opening and closing of the drain valve are avoided, and the failure rate is reduced. The invention also discloses a fuel cell system for implementing the fuel cell drain valve control method and a computer readable storage medium.

Description

Technical Field

[0001] The present invention belongs to the technical field of fuel cells, and in particular, relates to a fuel cell drain valve control method, a fuel cell system and a storage medium. Background Art

[0002] A large amount of liquid water will be generated during the operation of the fuel cell system. The water generated on the cathode side will be discharged along with the tail pipe, but the water that penetrates into the anode side needs to be controlled by the controller to open and close the hydrogen path drain valve according to actual needs, and the liquid water separated by the hydrogen path gas-liquid separator is discharged, so that the water content of the anode circulating hydrogen is in a suitable range, thereby maintaining the humidity of the proton exchange membrane at the optimal operating conditions.

[0003] The current widespread use of anode drainage control mainly relies on the following two methods:

[0004] 1. Relying on the liquid level sensor of the gas-liquid separator, when the liquid level sensor changes from 0 to 1, it means that the liquid level in the gas-liquid separator is high, and the drain valve needs to be opened to drain the water in time. When the liquid level sensor changes from 1 to 0, the drain valve needs to be closed after a necessary delay to end the drainage. This method is limited by the high failure rate of the liquid level sensor and it is easy to be frozen at low temperatures, causing the drain valve control input signal to be distorted, so the accuracy is poor.

[0005] 2. Use the current / power lookup table method, that is, determine the opening and closing time of the drain valve according to the current real-time current, and periodically open and close the drain valve. This method avoids the disadvantages of the liquid level sensor to a certain extent, but the actual amount of water generated by the fuel cell stack is related to the real-time current. When the current changes, it is not accurate to determine the drainage cycle based only on the current current. Too long drainage time will cause hydrogen leakage and waste, and too short drainage time will cause frequent opening and closing of the valve, affecting the life of the valve, and will also cause insufficient drainage and cause flooding.

[0006] It is desirable to provide an improved fuel cell drain valve control method, particularly with respect to how to reduce the system hydrogen consumption rate. Summary of the invention

[0007] The present invention aims to solve at least one of the technical problems existing in the prior art. To this end, the present invention provides a fuel cell drain valve control method, the purpose of which is to reduce the system hydrogen consumption rate.

[0008] In order to solve the above technical problems, the technical solution adopted by the present invention is: a fuel cell drain valve control method, comprising the steps of:

[0009] S1, obtain the current integral average value Q0 of the best time to open the drain valve;

[0010] S2, obtaining the integral value D0 of the hydrogen outlet pressure difference at the best time to close the drain valve;

[0011] S3, calculation of air pressure correction coefficient;

[0012] S4. When the set conditions are met, the drain valve is controlled to open and close to complete a drainage cycle.

[0013] The step S1 comprises:

[0014] S101, starting the fuel cell system, collecting and recording the fuel cell stack output current I after the drain valve completes the first drainage, and integrating the stack output current I with time;

[0015] S102, observing the gas-liquid separator, and when it is observed that the gas-liquid separator needs to be drained, recording the current integral value Q of the drain valve at this time;

[0016] S103, repeating step S101 and step S102 multiple times to obtain multiple current integral values ​​Q;

[0017] S104, calculating the current integral average value Q0, where the current integral average value Q0 is the average value of all current integral values ​​Q obtained.

[0018] The step S1 is performed under standard atmospheric pressure.

[0019] The step S2 comprises:

[0020] S201, open the drain valve to drain water, and clear the current integrated average value Q0;

[0021] S202, collecting the hydrogen outlet pressure P1 and integrating it, and when the liquid in the gas-liquid separator is emptied, recording the integral value D;

[0022] S203, repeating step S201 and step S202 for a set number of times to obtain multiple integral values ​​D;

[0023] S204, calculating the hydrogen outlet pressure difference integral value D0, where the hydrogen outlet pressure difference integral value D0 is the average value of all integral values ​​D obtained.

[0024] The setting number of times is 5 times.

[0025] The step S2 is performed under standard atmospheric pressure.

[0026] The step S3 comprises:

[0027] S301, changing the atmospheric pressure at the outlet of the drain valve in sequence according to the set sequence, and testing the pressure integral value D when the drain valve is closed under different atmospheric pressures in sequence ^ ;

[0028] S302, according to the formula β=D ^ / D0, calculate the pressure correction coefficient β under different atmospheric pressures.

[0029] In the step S4, the setting conditions are met including: the fuel cell system is turned on, the drain valve completes the first drainage, and the current integrated average value Q0 meets the requirement.

[0030] The present invention also provides a fuel cell system that implements the fuel cell drain valve control method, including a fuel cell stack, a pressure sensor, a current sensor, a drain valve and a gas-liquid separator, wherein the pressure sensor is configured to detect the pressure value at the hydrogen outlet, and the current sensor is configured to detect the output current of the fuel cell stack.

[0031] The present invention also provides a computer-readable storage medium, wherein the computer-readable storage medium stores computer-executable instructions, and the computer-executable instructions are used to enable a computer to execute the fuel cell drain valve control method.

[0032] The fuel cell drain valve control method of the present invention improves the precise control of the drain valve opening time, reduces the leakage of hydrogen from the drain valve, thereby reducing the system hydrogen consumption rate, and avoids frequent opening and closing of the drain valve, reducing the failure rate. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 Schematic diagram of the structure of the gas-liquid separator and the drain valve in the embodiment;

[0034] Figure 2 Schematic diagram of hydrogen pressure change during the opening process of the drain valve in the embodiment;

[0035] The marks in the above figure are: 1, gas-liquid separator inlet; 2, gas-liquid separator outlet; 3, drain valve outlet; L acu , Actual liquid level of gas-liquid separator; L min , the minimum value of the gas-liquid separator liquid level; P0, the stack outlet pressure before the drain valve is opened; P1, the stack outlet pressure when the drain valve is closed; T0, the time when the drain valve opens. DETAILED DESCRIPTION

[0036] The specific implementation methods of the present invention are further explained in detail below by describing the embodiments with reference to the accompanying drawings, with the aim of helping those skilled in the art to have a more complete, accurate and in-depth understanding of the concept and technical solution of the present invention and facilitating its implementation.

[0037] The present invention provides a fuel cell drain valve control method, comprising the following steps:

[0038] S1, obtain the current integral average value Q0 of the best time to open the drain valve;

[0039] S2, obtaining the integral value D0 of the hydrogen outlet pressure difference at the best time to close the drain valve;

[0040] S3, calculation of air pressure correction coefficient;

[0041] S4. When the set conditions are met, the drain valve is controlled to open and close to complete a drainage cycle.

[0042] The step S1 comprises:

[0043] S101, starting the fuel cell system, collecting and recording the fuel cell stack output current I after the drain valve completes the first drainage, and integrating the stack output current I with time;

[0044] S102, observing the gas-liquid separator, and when it is observed that the gas-liquid separator needs to be drained, recording the current integral value Q of the drain valve at this time;

[0045] S103, repeating step S101 and step S102 multiple times to obtain multiple current integral values ​​Q;

[0046] S104, calculating the current integral average value Q0, where the current integral average value Q0 is the average value of all current integral values ​​Q obtained.

[0047] The step S1 is performed under standard atmospheric pressure.

[0048] The step S2 comprises:

[0049] S201, open the drain valve to drain water, and clear the current integrated average value Q0;

[0050] S202, collecting the hydrogen outlet pressure P1 and integrating it, and when the liquid in the gas-liquid separator is emptied, recording the integral value D;

[0051] S203, repeating step S201 and step S202 for a set number of times to obtain multiple integral values ​​D;

[0052] S204, calculating the hydrogen outlet pressure difference integral value D0, where the hydrogen outlet pressure difference integral value D0 is the average value of all integral values ​​D obtained.

[0053] The setting number of times is 5 times.

[0054] The step S2 is performed under standard atmospheric pressure.

[0055] The step S3 comprises:

[0056] S301, changing the atmospheric pressure at the outlet of the drain valve in sequence according to the set sequence, and testing the pressure integral value D when the drain valve is closed under different atmospheric pressures in sequence ^ ;

[0057] S302, according to the formula β=D ^ / D0, calculate the pressure correction coefficient β under different atmospheric pressures.

[0058] In the step S4, the setting conditions are met including: the fuel cell system is turned on, the drain valve completes the first drainage, and the current integrated average value Q0 meets the requirement.

[0059] The present invention also provides a fuel cell system that implements the fuel cell drain valve control method, including a fuel cell stack, a pressure sensor, a current sensor, a drain valve and a gas-liquid separator, wherein the pressure sensor is configured to detect the pressure value at the hydrogen outlet, and the current sensor is configured to detect the output current of the fuel cell stack.

[0060] The present invention also provides a computer-readable storage medium, wherein the computer-readable storage medium stores computer-executable instructions, and the computer-executable instructions are used to enable a computer to execute the fuel cell drain valve control method.

[0061] Example

[0062] In a first aspect of the present invention, an embodiment of the present invention provides a fuel cell drain valve control method, comprising the following steps:

[0063] S1, obtain the current integral average value Q0 of the best time to open the drain valve;

[0064] S2, obtaining the integral value D0 of the hydrogen outlet pressure difference at the best time to close the drain valve;

[0065] S3, calculation of air pressure correction coefficient;

[0066] S4. When the set conditions are met, the drain valve is controlled to open and close to complete a drainage cycle.

[0067] Specifically, in the fuel cell system of the prior art, the drain valve is arranged at the bottom of the gas-liquid separator. The gas-liquid separator is used to separate the gas and liquid generated in the fuel cell system. The control method of the drain valve relies on the liquid level sensor of the gas-liquid separator. Due to the high failure rate of the liquid level sensor and the defect that it is easy to freeze at low temperature, it is easy to cause the liquid level sensor to not be in place. Therefore, the feedback signal of the drain valve control will be distorted, which will cause the drain valve to be unable to drain, or the drainage time control accuracy is poor, causing hydrogen to leak from the drain valve, and ultimately increasing the hydrogen consumption rate of the system.

[0068] In the embodiment of the present invention, the fixed-period drainage method based on current cannot solve the problem of drainage cycle variation caused by different drainage amounts due to current fluctuations under variable load conditions. The embodiment of the present invention proposes a new drainage valve control method, and the control logic is described as follows:

[0069] 1: The rate of water generation varies with the current size. From the power generation mechanism of the fuel cell, the greater the current during operation, the more water is generated. However, the generation of water is a cumulative process, and the current size at a certain moment cannot represent the amount of water generated over a period of time. Therefore, considering the accumulation effect of water during the operation of the system, the integral method is used: the current is integrated to obtain the current integral value Q that needs to open the drain valve when the gas-liquid separator reaches the ideal liquid level. Based on this value, the opening of the drain valve is precisely controlled to prevent the frequent operation of the drain valve.

[0070] 2: After the drain valve is determined, the main factor affecting the speed of drainage is the pressure difference before and after the drain valve. The greater the pressure difference, the faster the drainage. Similarly, the lower the pressure difference, the slower the drainage. The outlet pressure is the atmospheric pressure. Therefore, it is proposed to integrate the pressure at the front end of the drain valve, that is, the hydrogen outlet pressure, to obtain the pressure integral D when the liquid level is just emptied. Finally, the atmospheric pressure correction coefficient is combined to accurately control the valve closing to prevent incomplete water drainage or hydrogen leakage.

[0071] Based on the above two points, sufficient drainage is ensured while hydrogen leakage is avoided, the system hydrogen consumption rate is reduced, and the life of the drain valve is increased.

[0072] The drain valve control method provided in the embodiment of the present invention first obtains the integral value of the stack output current at the optimal drainage time of the fuel cell through testing. The specific operation is: after the fuel cell is started according to the normal process, the liquid level emptying operation is first performed, and then the drain valve closing operation is immediately performed. The fuel cell starts to operate according to normal working conditions, reads the output current of the fuel cell stack, and integrates the current. When the liquid level in the gas-liquid separator reaches the ideal drainage value, the current integral value Q at this time is recorded, and the above operation is repeated to obtain the current integral average value Q0.

[0073] Similarly, the above-mentioned similar method is used to obtain the pressure integral value of the optimal drainage time. The specific operation is: when the fuel cell is started and the drainage valve is opened, the hydrogen outlet pressure at the front end of the drainage valve is obtained. In the present invention, the front end of the drainage valve is arranged as a hydrogen outlet pressure sensor, and the hydrogen outlet pressure P1 is recorded. The hydrogen outlet pressure is integrated, and the integration is stopped when the liquid is completely discharged. The integral value D at this time is recorded, and the above operation is repeated to obtain the measured average value D0.

[0074] The actual working process is as follows: when the fuel cell system is turned on and the drain valve is in a closed state, the current is integrated immediately. When the integral reaches Q0, the drain valve is opened immediately and the integral is reset to zero. After the drain valve is opened, the hydrogen outlet pressure is integrated immediately. When the integral value reaches D0, the drain valve is closed immediately and the integral is reset to zero, that is, the drainage is determined to be completed, and the drain valve is closed immediately to prevent it from continuing to be opened and causing a sharp drop in the hydrogen pressure at the inlet and outlet of the fuel cell stack. This method ensures sufficient drainage without using a liquid level sensor, while also avoiding hydrogen leakage from the drain valve to the greatest extent, thereby increasing the life of the drain valve and achieving the purpose of reducing the hydrogen consumption rate of the fuel cell system.

[0075] In the embodiment of the present invention, the data required to be used by the fuel cell drain valve control method mainly include: the stack outlet current value (ie, DCDC input current) and the hydrogen outlet pressure value;

[0076] The stack outlet current value is collected by DCDC and sent to the fuel cell controller FCU through the CAN network; the hydrogen outlet pressure value is detected by the pressure sensor, which is arranged at the front end of the drain valve. The hydrogen outlet pressure value is detected by the pressure sensor arranged at the hydrogen outlet, and then collected and obtained by the fuel cell controller. The hydrogen outlet pressure value is used to characterize the pressure at the front end of the drain valve. The rear end of the drain valve is connected to the external environment, and the environmental pressure gauge arranged by the system is used to detect the outlet pressure value of the drain valve.

[0077] In the embodiment of the present invention, the above step S1 includes:

[0078] S101, starting the fuel cell system, collecting and recording the fuel cell stack output current I after the drain valve completes the first drainage, and integrating the stack output current I with time;

[0079] S102, observing the gas-liquid separator, and when it is observed that the gas-liquid separator needs to be drained, recording the current integral value Q of the drain valve at this time;

[0080] S103, repeating step S101 and step S102 multiple times to obtain multiple current integral values ​​Q;

[0081] S104 , calculating a current integral average value Q0 , where the current integral average value Q0 is an average value of all current integral values ​​Q obtained.

[0082] In an embodiment of the present invention, in the above step S101, the fuel cell system is started, and after starting according to the normal process and completing the first drainage, the fuel cell system operates according to the established operating conditions. At this time, the fuel cell stack output current I is collected and recorded, and the battery output current is integrated over time.

[0083] In the embodiment of the present invention, in the above step S104, all the obtained current integral values ​​Q are added up and then divided by the number of times step S101 and step S102 are repeated to obtain the current integral average value Q0. After the current integral average value Q0 is calculated, the current integral average value Q0 is frozen as a judgment value for the opening of the drain valve.

[0084] In the embodiment of the present invention, the above step S1 is performed under standard atmospheric pressure.

[0085] In the embodiment of the present invention, the above step S2 includes:

[0086] S201, open the drain valve to drain water, and clear the current integrated average value Q0;

[0087] S202, collecting the hydrogen outlet pressure value P1 and integrating it, and when the liquid in the gas-liquid separator is emptied, recording the integral value D;

[0088] S203, repeating step S201 and step S202 for a set number of times to obtain multiple integral values ​​D;

[0089] S204, calculating the hydrogen outlet pressure difference integral value D0, where the hydrogen outlet pressure difference integral value D0 is the average value of all integral values ​​D obtained.

[0090] In an embodiment of the present invention, in the above step S201, when the current integral value reaches the current integral average value Q0, it indicates that the liquid level in the gas-liquid separator has reached the set value and drainage is required. At this time, the drain valve is immediately opened to drain the water, and the current integral average value Q0 is cleared to zero.

[0091] In the embodiment of the present invention, in the above step S203, the number of times is set to 5, that is, step S201 and step S202 are repeated 5 times in total, and 5 integral values ​​D are obtained in total.

[0092] In the embodiment of the present invention, in the above step S204, all the five integral values ​​D obtained are added together and then divided by the number of times step S201 and step S202 are repeated to obtain the hydrogen outlet pressure differential integral value D0. After the hydrogen outlet pressure differential integral value D0 is calculated, the hydrogen outlet pressure differential integral value D0 is frozen as a judgment value for closing the drain valve.

[0093] In the embodiment of the present invention, the above step S2 is performed under standard atmospheric pressure.

[0094] In the above step S3, the air pressure correction coefficient is calculated. Among the factors affecting the drainage rate, the pressure at the front end of the drain valve is the main influencing factor. However, due to the complex operating environment of the vehicle, the increase in altitude will cause changes in air pressure, thereby causing changes in the pressure difference before and after the drain valve, which in turn affects the closing time of the drain valve. Therefore, the atmospheric pressure correction coefficient is proposed to correct the specific closing time of the drain valve.

[0095] In the above step S3, considering the difficulty of the current fuel cell system plateau experiment, the method of vacuuming to change the outlet pressure of the drain valve is used to simulate the change in altitude. The corresponding table of simulated altitude and air pressure is shown in Table 1:

[0096] Table 1 Correspondence between altitude and air pressure

[0097]

[0098]

[0099] In an embodiment of the present invention, the above step S3 includes:

[0100] S301, change the atmospheric pressure at the outlet of the drain valve in sequence according to the set sequence, and test the pressure integral value D when the drain valve is closed under different atmospheric pressures in sequence ^ ;

[0101] S302, according to the formula β=D ^ / D0, calculate the pressure correction coefficient β under different atmospheric pressures. The pressure correction coefficient β corresponds to the ambient pressure one by one and can be obtained by looking up the atmospheric pressure table later.

[0102] In the embodiment of the present invention, in the above step S301, a vacuum method is adopted, and the atmospheric pressure at the outlet of the drain valve is changed in sequence according to the corresponding table of altitude and air pressure, and the pressure integral value D when the drain valve is closed under different atmospheric pressures is tested in sequence. ^ , analyze the pressure integral value D when the drain valve is closed under different atmospheric pressures ^ of the changing trend.

[0103] In the embodiment of the present invention, in the above step S301, the setting order is that the altitude is set from the lowest value to the highest value, the lowest value is 0 meters, and the highest value is 3900 meters.

[0104] In the embodiment of the present invention, in the above step S4, satisfying the set conditions includes: the fuel cell system is turned on, the drain valve completes the first drainage, and the current integrated average value Q0 meets the requirement.

[0105] In the embodiment of the present invention, the specific implementation process of the above step S4 is as follows: after the fuel cell system is turned on and the first drainage is completed, the current is immediately integrated. When the integral value reaches the above current integral average value Q0, the drain valve is immediately controlled to open for drainage, and the current integral average value Q0 is cleared at the same time. When the drain valve is opened, the hydrogen outlet pressure is immediately integrated. When the integral value reaches the hydrogen outlet pressure differential integral value D0, it is determined that the drainage is completed, and the drain valve is immediately closed and the hydrogen outlet pressure differential integral value D0 is cleared. At the same time, the atmospheric pressure is read, and then the table is looked up to obtain the pressure correction coefficient β. After obtaining the pressure correction coefficient β, the pressure correction coefficient β is multiplied by the current integral average value D0 to obtain a new drain valve closing pressure integral value D0'. When the above calculated pressure integral value D0' reaches P0', the drain valve is closed, and a drainage cycle is completed. Wherein: the P0' value is the value actually tested by the experiment. When the fuel cell system is undergoing bench testing and calibration testing, a transparent tail pipe is installed so that the corresponding pressure integral value can be observed each time the drain valve is opened until the liquid water is drained at each operating point. This value is used as P0' at that operating point.

[0106] In the embodiment of the present invention, by repeatedly executing the above steps S1 to S4, efficient drainage of the drainage valve can be achieved.

[0107] Compared with the prior art, the above fuel cell drain valve control method has the following beneficial effects:

[0108] 1. The optimal opening time of the drain valve is obtained by using the current integral value. This method does not require the use of a liquid level sensor or any new components. It also solves the problem of inaccurate drainage control based on real-time current periodicity, avoids unreasonable or frequent opening of the drain valve, and increases the life of the drain valve.

[0109] 2. The optimal closing time of the drain valve is obtained by using the integral value of the hydrogen outlet pressure. This method can avoid the impact of hydrogen outlet pressure difference fluctuations on the drainage time without using a liquid level sensor or adding new components. The algorithm is simple and accurate, and can improve the precise control of the drain valve.

[0110] In the second aspect of the present invention, an embodiment of the present invention also provides a fuel cell system that implements the above-mentioned fuel cell drain valve control method, including a fuel cell stack, a pressure sensor, a current sensor, a drain valve and a gas-liquid separator, the drain valve is arranged at the bottom of the gas-liquid separator, the pressure sensor is arranged to detect the pressure value at the hydrogen outlet (i.e., the hydrogen outlet pressure value), and the current sensor is arranged to detect the output current of the fuel cell stack (i.e., the stack outlet current value).

[0111] In a third aspect of the present invention, an embodiment of the present invention further provides a computer-readable storage medium, wherein the computer-readable storage medium stores computer-executable instructions, and the computer-executable instructions are used to enable a computer to execute the above-mentioned fuel cell drain valve control method.

[0112] The device embodiments described above are merely illustrative, and the units described as separate components may or may not be physically separated, that is, they may be located in one place or distributed on multiple network units. Some or all of the modules may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0113] It will be appreciated by those skilled in the art that all or some of the steps and systems in the disclosed method above may be implemented as software, firmware, hardware and appropriate combinations thereof. Some physical components or all physical components may be implemented as software executed by a processor, such as a central processing unit, a digital signal processor or a microprocessor, or may be implemented as hardware, or may be implemented as an integrated circuit, such as an application specific integrated circuit. Such software may be distributed on a computer-readable medium, which may include a computer storage medium (or a non-transitory medium) and a communication medium (or a temporary medium). As known to those skilled in the art, the term computer storage medium includes volatile and non-volatile, removable and non-removable media implemented in any method or technology for storing information (such as computer-readable instructions, data structures, program modules or other data). Computer storage media include, but are not limited to, RAM, ROM, EEPROM, flash memory or other memory technologies, CD-ROM, digital versatile disks (DVD) or other optical disk storage, magnetic cassettes, magnetic tapes, disk storage or other magnetic storage devices, or any other medium that may be used to store desired information and may be accessed by a computer. Furthermore, it is well known to those skilled in the art that communication media typically embodies computer readable instructions, data structures, program modules, or other data in a modulated data signal such as a carrier wave or other transport mechanism, and may include any information delivery media.

[0114] The present invention is described above by way of example in conjunction with the accompanying drawings. It is obvious that the specific implementation of the present invention is not limited to the above-mentioned method. As long as various non-substantial improvements are made using the method concept and technical solution of the present invention, or the concept and technical solution of the present invention are directly applied to other occasions without improvement, they are all within the protection scope of the present invention.

Claims

1. A fuel cell drain valve control method, characterized in that: Includes steps: S1, obtain the current integral average value Q0 of the best time to open the drain valve; S2, obtaining the integral value D0 of the hydrogen outlet pressure difference at the best time to close the drain valve; S3, calculation of air pressure correction coefficient; S4. When the set conditions are met, the drain valve is controlled to open and close to complete a drainage cycle.

2. The fuel cell drain valve control method according to claim 1, characterized in that: The step S1 comprises: S101, starting the fuel cell system, collecting and recording the fuel cell stack output current I after the drain valve completes the first drainage, and integrating the stack output current I with time; S102, observe the gas-liquid separator, and when it is observed that the gas-liquid separator needs to be drained, record the current integral value Q of the drain valve at this time; S103, repeating step S101 and step S102 multiple times to obtain multiple current integral values ​​Q; S104, calculating the current integral average value Q0, where the current integral average value Q0 is the average value of all current integral values ​​Q obtained.

3. The fuel cell drain valve control method according to claim 1, characterized in that: The step S1 is performed under standard atmospheric pressure.

4. The fuel cell drain valve control method according to any one of claims 1 to 3, characterized in that: The step S2 comprises: S201, open the drain valve to drain water, and clear the current integrated average value Q0; S202, collecting the hydrogen outlet pressure P1 and integrating it, and when the liquid in the gas-liquid separator is emptied, recording the integral value D; S203, repeating step S201 and step S202 for a set number of times to obtain multiple integral values ​​D; S204, calculating the hydrogen outlet pressure difference integral value D0, where the hydrogen outlet pressure difference integral value D0 is the average value of all integral values ​​D obtained.

5. The fuel cell drain valve control method according to claim 4, characterized in that: The setting number of times is 5 times.

6. The fuel cell drain valve control method according to any one of claims 1 to 5, characterized in that: The step S2 is performed under standard atmospheric pressure.

7. The fuel cell drain valve control method according to any one of claims 1 to 5, characterized in that: The step S3 comprises: S301, changing the atmospheric pressure at the outlet of the drain valve in sequence according to the set sequence, and testing the pressure integral value D when the drain valve is closed under different atmospheric pressures in sequence ^ ; S302, according to the formula β=D ^ / D0, calculate the pressure correction coefficient β under different atmospheric pressures.

8. The fuel cell drain valve control method according to any one of claims 1 to 5, characterized in that: In the step S4, the setting conditions are met including: the fuel cell system is turned on, the drain valve completes the first drainage, and the current integrated average value Q0 meets the requirement.

9. A fuel cell system implementing the fuel cell drain valve control method according to any one of claims 1 to 8, characterized in that: It includes a fuel cell stack, a pressure sensor, a current sensor, a drain valve and a gas-liquid separator. The pressure sensor is configured to detect the pressure value at the hydrogen outlet, and the current sensor is configured to detect the output current of the fuel cell stack.

10. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores computer-executable instructions, and the computer-executable instructions are used to enable a computer to execute the fuel cell drain valve control method according to any one of claims 1 to 9.

Images