Fault diagnosis method, system and device for anode drain valve of hydrogen fuel cell

Abstract

According to the fault diagnosis method for the anode drain valve of the hydrogen fuel cell provided by the invention, the actual working state of the drain valve can be more accurately judged by acquiring the hydrogen pressure compensation values when the drain valve is closed and opened as well as the average separation difference and the tail discharge hydrogen concentration when the drain valve operates abnormally and normally. According to the method, whether the drain valve fails to be opened or closed or not can be reflected more accurately by comparing the difference relations of the calculation parameters, so that the possibility of misjudgment is reduced, the fault of the drain valve can be diagnosed timely and accurately, performance reduction or damage of a battery caused by unsmooth drainage can be avoided, and the service life of the battery is prolonged.

Description

Technical Field

[0001] The present application relates to the field of fuel cells, and in particular to a method for diagnosing faults of an anode drain valve of a hydrogen fuel cell. Background Art

[0002] A hydrogen fuel cell is a clean and efficient energy conversion device. The reaction product of a hydrogen fuel cell is water. If the water generated in the cell cannot be discharged in time, the gas diffusion layer and the catalyst layer will be covered with water, causing flooding. The flooding phenomenon causes the battery output performance to be low, reduces the battery life, and in severe cases, causes the battery to be reversed. Therefore, in order to ensure the efficient and stable operation of the fuel cell, the water in the battery needs to be discharged in time. Usually, the water generated by the battery cathode is discharged through excess air, while the water at the anode is discharged by pulse drainage by adding a water distributor and a drain valve in the circulation loop. The pulse drainage method is to periodically open and close the drain valve after the water distributor at the anode outlet of the fuel cell. When the drain valve is closed, a certain pressure is maintained in the battery. After an appropriate period of time, when the drain valve outlet is opened, due to the pressure difference between the inside and the outside, the anode reaction gas carries the water out of the battery to achieve the purpose of drainage. Whether the drain valve works properly affects the normal operation of the fuel cell system. If the drain valve cannot be opened normally, the water in the anode cannot be discharged normally. The water will repeatedly enter the fuel cell stack with the circulating hydrogen, causing anode flooding and affecting the normal operation of the fuel cell system. If the drain valve cannot be closed normally, water and hydrogen will be continuously discharged, resulting in poor hydrogen utilization, hydrogen pressure unable to maintain the reaction demand pressure, and high tail exhaust hydrogen concentration. The system cannot operate normally. Therefore, it is extremely important to diagnose the fault of the drain valve. Rapid identification of the fault of the drain valve can prevent more serious faults of the fuel cell in advance.

[0003] At present, the existing technology only determines the fault state by judging the hydrogen pressure and pressure control duty cycle during the opening of the drain valve, and cannot accurately identify whether the pressure and duty cycle changes are caused by abnormal drain valves, abnormal pressure control devices, abnormal front-end hydrogen pressure supply, or other interference. If the drain valve cannot be closed normally, it will cause water and hydrogen to be continuously discharged, resulting in poor hydrogen utilization, hydrogen pressure unable to maintain the required reaction pressure, and high tail exhaust hydrogen concentration. The system will also not be able to operate normally. In actual operation, the operating parameters in the initial time period are used as the judgment parameters for the normal state. If the drain valve itself has a fault from the beginning, it cannot be identified in the first time, and the fault data may be defaulted as normal data, so there is a possibility of false alarm of the fault, resulting in reduced accuracy.

[0004] Therefore, it is necessary to provide a hydrogen fuel cell anode drain valve fault diagnosis method that can more accurately determine the fault state of the drain valve and reduce the possibility of misjudgment. Summary of the invention

[0005] In view of this, it is necessary to provide a hydrogen fuel cell anode drain valve fault diagnosis method that can more accurately judge the fault state of the drain valve and reduce the possibility of misjudgment, so as to solve the above problems.

[0006] The embodiment of the present application provides a method for diagnosing a fault of an anode drain valve of a hydrogen fuel cell, comprising the steps of:

[0007] Obtain the hydrogen pressure compensation value PWM1 when the drain valve is closed and the hydrogen pressure compensation value PWM2 when the drain valve is opened for T time, and calculate the hydrogen pressure compensation difference ΔPWM when the drain valve is opened for T time;

[0008] Obtain the mean difference Dev and tail discharge hydrogen concentration HCon when the drain valve is abnormal and operating normally;

[0009] Obtain the mean difference limit Dev1 when the drain valve fails to open and operates and the mean difference limit Dev2 when the drain valve operates normally, and calculate the mean difference difference ΔDev;

[0010] Obtain the tail exhaust hydrogen concentration HCon1 when the drain valve fails to close and operates and the tail exhaust hydrogen concentration HCon2 when it operates normally, and calculate the tail exhaust hydrogen concentration difference ΔHCon;

[0011] Obtain tail exhaust hydrogen concentration HCon3 and deviation Dev3 in real time when the hydrogen fuel cell is working, and calculate hydrogen pressure compensation value PWM3 of the drain valve;

[0012] Calculate and obtain in real time the difference between the hydrogen pressure compensation value PWM3 of the drain valve when the hydrogen fuel cell is working and the hydrogen pressure compensation value PWM1 when the drain valve is closed, and compare the difference with the hydrogen pressure compensation difference ΔPWM and P1 at the time T when the drain valve is opened, so as to judge the state of the drain valve;

[0013] If the drain valve is in the open state, and the difference between the deviation Dev3 obtained in real time when the hydrogen fuel cell is working and the deviation Dev obtained when the drain valve is abnormal and operating normally is calculated, if the difference is greater than or equal to the deviation ΔDev, it is determined that the drain valve fails to open;

[0014] If the drain valve is in closed state, and the difference between the tail exhaust hydrogen concentration HCon3 obtained in real time when the hydrogen fuel cell is working and the tail exhaust hydrogen concentration HCon obtained when the drain valve is abnormal and operating normally is calculated, if the difference is greater than or equal to the tail exhaust hydrogen concentration difference ΔHCon, it is determined that the drain valve has failed to close.

[0015] In at least one embodiment of the present application, the "calculating the difference between the hydrogen pressure compensation value PWM3 of the drain valve when the hydrogen fuel cell is working and the hydrogen pressure compensation value PWM1 when the drain valve is closed, comparing the difference with the hydrogen pressure compensation difference ΔPWM and P1 at the time T when the drain valve is opened, so as to determine the state of the drain valve" includes the steps of: determining the state of the drain valve, if the difference between the hydrogen pressure compensation value PWM3 of the drain valve when the hydrogen fuel cell is working and the hydrogen pressure compensation value PWM1 when the drain valve is closed is less than or equal to P1, then determining that the drain valve is in the open state; if the difference between the hydrogen pressure compensation value PWM3 of the drain valve when the hydrogen fuel cell is working and the hydrogen pressure compensation value PWM1 when the drain valve is closed is greater than or equal to the hydrogen pressure compensation difference ΔPWM at the time T when the drain valve is opened, then determining that the drain valve is in the closed state.

[0016] In at least one embodiment of the present application, the PI is a preset value to compare the magnitude relationship between the hydrogen pressure compensation value PWM3 and the hydrogen pressure compensation value PWM1.

[0017] The embodiment of the present application provides a hydrogen fuel cell anode drain valve fault diagnosis system, which, when in operation, runs the hydrogen fuel cell anode drain valve fault diagnosis method as described above, and the diagnosis system includes a data acquisition module, a data processing module and a state diagnosis module;

[0018] The data acquisition module is used to collect data values ​​such as hydrogen pressure compensation value, deviation from the mean and tail exhaust hydrogen concentration;

[0019] The data processing module is used to calculate the data value from the data acquisition module;

[0020] The state processing module is used to determine whether the drain valve fails to open or close based on the calculated data value, and perform fault processing accordingly.

[0021] In at least one embodiment of the present application, the data processing module includes a first processing module and a second processing module; the first processing module is used to calculate the difference in hydrogen pressure compensation values; the second processing module is used to calculate the deviation from the mean and the tail exhaust hydrogen concentration value.

[0022] In at least one embodiment of the present application, the status processing module includes a first diagnostic result module and a second diagnostic result module; the first diagnostic result module determines the status of the drain valve according to the first processing module; the second diagnostic result module obtains the status diagnosis result of the drain valve according to the judgment of the second processing module and the first diagnostic result module.

[0023] An embodiment of the present application provides a hydrogen fuel cell anode drain valve fault diagnosis device, the diagnosis device includes an air intake channel, an air outlet channel and a battery stack, the air intake channel is connected to the cathode of the battery stack, and the anode of the battery stack is connected to the air outlet channel; wherein the air intake channel includes a hydrogen proportional valve and a sensor assembly connected to the hydrogen proportional valve, the air outlet channel includes a water separator and a drain valve, the sensor assembly is connected to the cathode of the battery stack, one end of the water separator is connected to the anode of the battery stack, and the other end is connected to the drain valve.

[0024] In at least one embodiment of the present application, the air intake passage further includes an ejector, one end of the ejector is connected to the hydrogen proportional valve and the water separator, and the other end of the ejector is connected to the sensor assembly.

[0025] In at least one embodiment of the present application, 9. A hydrogen fuel cell anode drain valve fault diagnosis device according to claim 8, characterized in that the sensor assembly includes a pressure sensor and a temperature sensor connected to the pressure sensor, the pressure sensor is connected to the hydrogen proportional valve, and the temperature sensor is connected to the cathode of the battery stack.

[0026] In at least one embodiment of the present application, the diagnostic device further includes a gas storage device and a tail exhaust treatment device, the gas storage device is connected to the air intake passage, and the tail exhaust treatment device is connected to the air outlet passage.

[0027] The above-mentioned hydrogen fuel cell anode drain valve fault diagnosis method can more accurately judge the actual working state of the drain valve by obtaining the hydrogen pressure compensation value when the drain valve is closed and opened, as well as the deviation from the mean and tail exhaust hydrogen concentration when the drain valve is abnormal and normal. By comparing the difference relationship of the calculated parameters, it can more accurately reflect whether the drain valve fails to open or close, thereby reducing the possibility of misjudgment, making it possible to diagnose the drain valve fault in a timely and accurate manner, avoiding battery performance degradation or damage caused by poor drainage, and extending battery life. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 This is a flowchart of a method for diagnosing a fault of an anode drain valve of a hydrogen fuel cell in an embodiment of the present application.

[0029] Figure 2 It is a structural schematic diagram of a hydrogen fuel cell anode drain valve fault diagnosis device in an embodiment of the present application.

[0030] Figure 3 It is a structural schematic diagram of the air inlet channel and the air outlet channel in a hydrogen fuel cell anode drain valve fault diagnosis device in an embodiment of the present application.

[0031] Figure 4 This is a flow chart of the fault status of a method for diagnosing a fault of an anode drain valve of a hydrogen fuel cell in an embodiment of the present application.

[0032] Main component symbols

[0033] 100. A fault diagnosis device for an anode drain valve of a hydrogen fuel cell; 10. an air intake passage; 11. a hydrogen proportional valve; 12. an ejector; 13. a sensor assembly; 20. an air outlet passage; 21. a water separator; 22. a drain valve; 30. a battery stack; 131. a pressure sensor; 132. a temperature sensor; 40. a gas storage device; 50. a tail exhaust treatment device. DETAILED DESCRIPTION

[0034] The embodiments of the present application will be described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments.

[0035] It should be noted that when a component is considered to be "connected" to another component, it may be directly connected to the other component or there may be a central component at the same time. When a component is considered to be "located on" another component, it may be directly located on the other component or there may be a central component at the same time. The terms "top", "bottom", "upper", "lower", "left", "right", "front", "back", and similar expressions used herein are for illustrative purposes only.

[0036] The embodiment of the present application provides a method for diagnosing a fault of an anode drain valve of a hydrogen fuel cell, comprising the steps of:

[0037] Obtain the hydrogen pressure compensation value PWM1 when the drain valve is closed and the hydrogen pressure compensation value PWM2 when the drain valve is opened for T time, and calculate the hydrogen pressure compensation difference ΔPWM when the drain valve is opened for T time;

[0038] Obtain the mean difference Dev and tail discharge hydrogen concentration HCon when the drain valve is abnormal and operating normally;

[0039] Obtain the mean difference limit Dev1 when the drain valve fails to open and operates and the mean difference limit Dev2 when the drain valve operates normally, and calculate the mean difference difference ΔDev;

[0040] Obtain the tail exhaust hydrogen concentration HCon1 when the drain valve fails to close and operates and the tail exhaust hydrogen concentration HCon2 when it operates normally, and calculate the tail exhaust hydrogen concentration difference ΔHCon;

[0041] Obtain tail exhaust hydrogen concentration HCon3 and deviation Dev3 in real time when the hydrogen fuel cell is working, and calculate hydrogen pressure compensation value PWM3 of the drain valve;

[0042] Calculate and obtain in real time the difference between the hydrogen pressure compensation value PWM3 of the drain valve when the hydrogen fuel cell is working and the hydrogen pressure compensation value PWM1 when the drain valve is closed, and compare the difference with the hydrogen pressure compensation difference ΔPWM and P1 at the time T when the drain valve is opened, so as to judge the state of the drain valve;

[0043] If the drain valve is in the open state, and the difference between the deviation Dev3 obtained in real time when the hydrogen fuel cell is working and the deviation Dev obtained when the drain valve is abnormal and operating normally is calculated, if the difference is greater than or equal to the deviation ΔDev, it is determined that the drain valve fails to open;

[0044] If the drain valve is in closed state, and the difference between the tail exhaust hydrogen concentration HCon3 obtained in real time when the hydrogen fuel cell is working and the tail exhaust hydrogen concentration HCon obtained when the drain valve is abnormal and operating normally is calculated, if the difference is greater than or equal to the tail exhaust hydrogen concentration difference ΔHCon, it is determined that the drain valve has failed to close.

[0045] The above-mentioned hydrogen fuel cell anode drain valve fault diagnosis method can more accurately judge the actual working state of the drain valve by obtaining the hydrogen pressure compensation value when the drain valve is closed and opened, as well as the deviation from the mean and tail exhaust hydrogen concentration when the drain valve is abnormal and normal. By comparing the difference relationship of the calculated parameters, it can more accurately reflect whether the drain valve fails to open or close, thereby reducing the possibility of misjudgment, making it possible to diagnose the drain valve fault in a timely and accurate manner, avoiding battery performance degradation or damage caused by poor drainage, and extending battery life.

[0046] Some embodiments of the present application are described in detail below in conjunction with the accompanying drawings. In the absence of conflict, the following embodiments and features in the embodiments can be combined with each other.

[0047] according to Figure 1-Figure 4 In an embodiment of the present application, a method for diagnosing a fault of an anode drain valve of a hydrogen fuel cell is provided, comprising the steps of:

[0048] S100, obtaining a hydrogen pressure compensation value PWM1 when the drain valve is closed and a hydrogen pressure compensation value PWM2 when the drain valve is opened for T time, and calculating a hydrogen pressure compensation difference ΔPWM when the drain valve is opened for T time;

[0049] S200, obtaining the mean difference Dev and tail discharge hydrogen concentration HCon when the drain valve is abnormal and operating normally;

[0050] S300, obtaining a deviation limit value Dev1 when the drain valve fails to open and operates and a deviation limit value Dev2 when the drain valve operates normally, and calculating a deviation difference value ΔDev;

[0051] S400, obtaining the tail exhaust hydrogen concentration HCon1 when the drain valve fails to close and operates and the tail exhaust hydrogen concentration HCon2 when the drain valve operates normally, and calculating the tail exhaust hydrogen concentration difference ΔHCon;

[0052] S500, obtaining in real time the tail exhaust hydrogen concentration HCon3 and the deviation from the mean Dev3 when the hydrogen fuel cell is working, and calculating the hydrogen pressure compensation value PWM3 of the drain valve;

[0053] S600, calculating and obtaining in real time the difference between the hydrogen pressure compensation value PWM3 of the drain valve when the hydrogen fuel cell is working and the hydrogen pressure compensation value PWM1 when the drain valve is closed, and comparing the difference with the hydrogen pressure compensation difference ΔPWM and P1 at the time T when the drain valve is opened, so as to determine the state of the drain valve;

[0054] S700, if the drain valve is in the open state, and the difference between the deviation Dev3 obtained in real time when the hydrogen fuel cell is working and the deviation Dev obtained when the drain valve is abnormal and operating normally is calculated, if the difference is greater than or equal to the deviation ΔDev, it is determined that the drain valve fails to open;

[0055] S800. If the drain valve is in closed state, and the difference between the tail exhaust hydrogen concentration HCon3 obtained in real time when the hydrogen fuel cell is working and the tail exhaust hydrogen concentration HCon obtained when the drain valve is abnormal and operating normally is calculated, if the difference is greater than or equal to the tail exhaust hydrogen concentration difference ΔHCon, it is determined that the drain valve has failed to close.

[0056] Specifically, step S100: confirm the hydrogen pressure compensation value PWM1 at each current point in steady state (i.e. when the drain valve is not open). It should be noted that PWM1 takes the average value during the stable operation time, and obtains the hydrogen pressure compensation value PWM2 at T time after the drain valve is opened. The T time is a value determined by experiments. The hydrogen pressure compensation value PWM2 needs to take the average value under multiple cycles at the same current point, and determine that the difference between the hydrogen pressure compensation at the moment T when the drain valve is opened and the steady state is ΔPWM.

[0057] Step S200: Collect the deviation from the mean Dev and tail exhaust hydrogen concentration HCon at each current point when the hydrogen fuel cell is operating normally and the drain valve is abnormal. The deviation from the mean is the difference between the average and minimum values ​​of the cell stack single chip voltage.

[0058] Step S300: Determine the difference between the mean difference limit when the drain valve fails to open and operates and the mean difference limit when the drain valve operates normally, which is ΔDev.

[0059] Step S400: Determine the difference between the tail exhaust hydrogen concentration when the drain valve fails to close and operates and the tail exhaust hydrogen concentration when the drain valve operates normally, which is ΔHCon.

[0060] Step S500: acquiring the tail exhaust hydrogen concentration HCon3 and the deviation Dev3 of the hydrogen fuel cell in real time when the fuel cell is working, and calculating the hydrogen pressure compensation value PWM3 of the drain valve.

[0061] Step S600: Calculate the difference between the hydrogen pressure compensation value PWM3 of the drain valve when the hydrogen fuel cell is working and the hydrogen pressure compensation value PWM1 when the drain valve is closed, and compare the difference with the hydrogen pressure compensation difference ΔPWM and P1 at the moment T when the drain valve is opened, so as to determine the state of the drain valve.

[0062] Step S600 specifically includes the following steps:

[0063] S610: Determine the state of the drain valve. If the difference between the hydrogen pressure compensation value PWM3 of the drain valve obtained in real time when the hydrogen fuel cell is working and the hydrogen pressure compensation value PWM1 when the drain valve is closed is less than or equal to P1, the drain valve is determined to be in the open state.

[0064] Further, it is determined whether the drain valve state Sta is open, when it is open, Sta is 1, and when it is closed, Sta is 0. The preset value of PI can be a value preset within 0-10, 1-5, to determine that the smaller the difference between the hydrogen pressure compensation value PWM3 and the hydrogen pressure compensation value PWM1, the closer the range of the hydrogen pressure compensation value PWM3 and the hydrogen pressure compensation value PWM1.

[0065] When the drain valve is opened, the program sets Sta1=1 when it is opened. If the detected hydrogen pressure compensation value PWM3-PWM1≤P1, it is judged that the current drain valve may be in a state of opening failure, and the opening failure fault state Sta1=1. The difference between PWM3 and PWM1 is continuously detected. If PWM3–PWM1≥ΔPWM appears, the program determines Sta1=0 at this time. The program determines that it was a misjudgment just now, and the drain valve is operating normally. Only when the difference in the hydrogen pressure compensation value is PWM3-PWM1≤P1 in the continuous opening cycle, Sta1 is always set to 1, and it is judged that the current drain valve may be in a state of opening failure.

[0066] S620: If the difference between the hydrogen pressure compensation value PWM3 of the drain valve obtained in real time when the hydrogen fuel cell is working and the hydrogen pressure compensation value PWM1 when the drain valve is closed is greater than or equal to the hydrogen pressure compensation difference ΔPWM at the moment T when the drain valve is opened, the drain valve is determined to be in a closed state.

[0067] Furthermore, when the drain valve is closed, the program sets Sta2 = 0 when closed. If the detected compensation PWM3-PWM1≥ΔPWM, it is determined that the current drain valve may have failed to close, and the closing failure fault state Sta2 = 1. The difference between PWM3 and PWM1 is continuously detected. If PWM3–PWM1≤P1 appears, Sta2 = 0, and the program determines that it was a misjudgment and the drain valve operates normally. Only when PWM3-PWM1≥ΔPWM is continuously closed in the continuous closing cycle, Sta2 is always set to 1, and it is determined that the current drain valve may have failed to close.

[0068] Step 700: When the opening failure fault state Sta1=1 is detected and the deviation from the mean Dev3-Dev≥ΔDev, a drain valve opening failure fault is reported.

[0069] Step S800: When the closing failure fault state Sta2=1 is detected and the hydrogen concentration HCon3-HCon≥ΔHCon, a drain valve closing failure fault is reported.

[0070] If there is a fault, the fuel cell will be shut down to check the fault, otherwise it will operate normally.

[0071] The embodiment of the present application also provides a hydrogen fuel cell anode drain valve fault diagnosis system, which, when in operation, runs the hydrogen fuel cell anode drain valve fault diagnosis method as described above, including a data acquisition module, a data processing module and a state diagnosis module;

[0072] The data acquisition module is used to collect data values ​​such as hydrogen pressure compensation value, deviation from the mean and tail exhaust hydrogen concentration.

[0073] The data processing module is used to calculate the data value from the data acquisition module;

[0074] The state processing module is used to determine whether the drain valve fails to open or close based on the calculated data value, and perform fault processing accordingly.

[0075] Specifically, the data collected by the fuel cell controller data acquisition mainly include the hydrogen pressure compensation value PWM when the drain valve is not opened; the hydrogen pressure compensation value PWM2 at T time after the drain valve is opened; the deviation from the mean Dev and the tail exhaust hydrogen concentration HCon when the drain valve is abnormal and operates normally; the deviation from the mean limit Dev1 when the drain valve fails to open and operates, and the deviation from the mean limit Dev2 when it operates normally; the tail exhaust hydrogen concentration HCon1 when the drain valve fails to close and operates, and the tail exhaust hydrogen concentration HCon2 when it operates normally; the tail exhaust hydrogen concentration HCon3 and the deviation from the mean Dev3 when the hydrogen fuel cell is working, etc., to ensure the real-time transmission of data values, and then accurately judge the fault problem.

[0076] The data processing module further calculates and compares each data value of the data acquisition module to determine the result of the calculation and the result of the set comparison value P1.

[0077] The state processing module determines the fault state of the drain valve according to the calculation results and the comparison results.

[0078] In a specific embodiment, the data processing module includes a first processing module and a second processing module; the first processing module is used to calculate the difference of hydrogen pressure compensation value; the second processing module is used to calculate the deviation from the mean and the tail exhaust hydrogen concentration value.

[0079] In a specific embodiment, the status processing module includes a first diagnostic result module and a second diagnostic result module; the first diagnostic result module determines the status of the drain valve according to the first processing module; the second diagnostic result module obtains the status diagnosis result of the drain valve according to the judgment of the second processing module and the first diagnostic result module.

[0080] Specifically, the first diagnosis result module determines whether the drain valve is in an open or closed state. The second diagnosis result module determines whether the fault of the drain valve is a closing failure or an opening failure, thereby performing fault processing.

[0081] In the embodiment of the present application, a fault diagnosis device 100 for a hydrogen fuel cell anode drain valve 22 is also provided, the diagnostic device comprising an intake channel 10, an outlet channel 20 and a battery stack 30, the intake channel 10 being connected to the cathode of the battery stack 30, and the anode of the battery stack 30 being connected to the outlet channel 20. The intake channel 10 comprises a hydrogen proportional valve 11 and a sensor assembly 13 connected to the ejector 12, the outlet channel 20 comprises a water separator 21 and a drain valve 22; wherein the sensor assembly 13 is connected to the cathode of the battery stack 30, one end of the water separator 21 is connected to the anode of the battery stack 30, and the other end is connected to the drain valve 22.

[0082] In a specific embodiment, the air intake passage further includes an ejector, one end of the ejector is connected to the hydrogen proportional valve and the water separator, and the other end is connected to the sensor assembly.

[0083] Specifically, the air inlet channel 10 introduces gases such as hydrogen into the cathode of the battery stack 30, and the air outlet channel 20 is responsible for extracting the water vapor generated by the reaction and the unreacted hydrogen from the anode of the battery stack 30. After the hydrogen enters the stack to react, there will be water at the anode that has penetrated from the cathode due to the concentration difference, and the gas enters the cathode of the battery stack 30 through the air inlet channel 10. At the cathode, oxygen combines with the protons in the electrolyte and the electrons from the external circuit to generate water. At the same time, hydrogen undergoes an oxidation reaction at the anode, releasing electrons and protons. Electrons flow to the cathode through the external circuit, while protons reach the cathode through the electrolyte membrane. The generated water and unreacted hydrogen are discharged through the air outlet channel 20 to ensure that the performance of the battery is not affected by water accumulation inside.

[0084] Furthermore, the water separator 21 is used to separate the water generated by the anode of the battery stack 30 and the discharged hydrogen to prevent water from entering the battery stack and avoid flooding. The pressure of the anode hydrogen loop is controlled by the hydrogen proportional valve 11, and the hydrogen pressure of the anode loop is controlled by controlling the duty cycle of the hydrogen proportional valve 11. After the hydrogen enters the battery stack for reaction, there will be water infiltrated from the cathode due to the concentration difference at the anode. The water separator 21 and the drain valve 22 are installed on the outlet channel of the battery stack, and the water is taken out of the battery stack and drained away by hydrogen circulation. Usually, the drain valve 22 will drain water at a fixed opening frequency, and will also discharge part of the hydrogen. In order to ensure that the hydrogen pressure fluctuates within a small range, the hydrogen pressure control will calculate the hydrogen pressure compensation value according to the value of the hydrogen pressure drop when the drain valve 22 is opened, and act on the hydrogen proportional valve 11. Therefore, if the drain valve 22 is opened abnormally, the hydrogen pressure will not drop significantly, and the calculated hydrogen pressure compensation value will not fluctuate greatly (consistent with the steady-state value). However, if the water in the anode loop is not discharged normally, the hydrogen circulation will bring the water back into the stack, which is likely to cause local flooding of the anode of the stack and a local single low phenomenon. If the drain valve 22 is not closed normally, the hydrogen pressure will drop significantly. At this time, the calculated hydrogen pressure compensation value will be significantly higher than the steady-state value, and the tail exhaust hydrogen concentration will be significantly higher than the normal value. This application judges the abnormal opening or closing failure of the drain valve 22 based on this phenomenon.

[0085] In a specific embodiment, the sensor assembly 13 includes a pressure sensor 131 and a temperature sensor 132 connected to the pressure sensor 131 , the pressure sensor 131 is connected to the hydrogen proportional valve 11 , and the temperature sensor 132 is connected to the cathode of the battery stack 30 .

[0086] Specifically, the pressure data detected by the pressure sensor 131 is transmitted to the control system. If the pressure exceeds the preset range, the control system will adjust the opening of the hydrogen proportional valve 11 to increase or decrease the hydrogen supply, thereby adjusting the pressure to a safe and appropriate level. The temperature data detected by the temperature sensor 132 is also transmitted to the control system. If the temperature exceeds the optimal operating range, the control system may adjust the operation of the cooling system, or adjust the temperature by adjusting the supply ratio of hydrogen and oxygen to ensure that the battery stack 30 operates at the optimal temperature.

[0087] In a specific embodiment, the diagnostic device further includes a gas storage device 40 and a tail exhaust treatment device 50 , wherein the gas storage device 40 is connected to the air intake passage 10 , and the tail exhaust treatment device 50 is connected to the air outlet passage 20 .

[0088] Specifically, hydrogen is stored for use by the battery stack 30. The gas storage 40 can regulate the supply of hydrogen to ensure stable pressure and flow of hydrogen. The tail gas discharged from the battery stack 30 is processed, including unreacted hydrogen and generated water. The tail gas treatment device 50 can separate and recover useful components to reduce emissions, and is also used to detect tail gas hydrogen concentration.

[0089] Further, hydrogen is drawn out from the gas storage 40, enters the ejector 12 after being regulated by the proportional valve, and is supplied to the battery stack 30 after being mixed with oxygen. The gas storage 40 is managed by the control system to ensure that hydrogen is supplied on demand in response to changes in demand of the battery stack 30. The tail gas discharged from the battery stack 30 first enters the water separator 21 to remove most of the water. The remaining gas enters the tail gas treatment device 50 through the drain valve 22 for further treatment.

[0090] Thus, the above-mentioned hydrogen fuel cell anode drain valve fault diagnosis method can more accurately judge the actual working state of the drain valve by obtaining the hydrogen pressure compensation value when the drain valve is closed and opened, as well as the deviation from the mean and tail exhaust hydrogen concentration when the drain valve is abnormal and normal. By comparing the difference relationship of the calculated parameters, it can more accurately reflect whether the drain valve fails to open or close, thereby reducing the possibility of misjudgment, making it possible to diagnose the drain valve fault in a timely and accurate manner, avoiding battery performance degradation or damage caused by poor drainage, and extending battery life.

[0091] The above is only an implementation method of the present application. It should be pointed out that a person skilled in the art can make improvements without departing from the inventive concept of the present application, but these improvements are within the scope of protection of the present application.

Claims

1. A method for diagnosing a fault of an anode drain valve of a hydrogen fuel cell, characterized in that: Includes steps: Obtain the hydrogen pressure compensation value PWM1 when the drain valve is closed and the hydrogen pressure compensation value PWM2 when the drain valve is opened for T time, and calculate the hydrogen pressure compensation difference ΔPWM when the drain valve is opened for T time; Obtain the mean difference Dev and tail discharge hydrogen concentration HCon when the drain valve is abnormal and operating normally; Obtain the mean difference limit Dev1 when the drain valve fails to open and operates and the mean difference limit Dev2 when the drain valve operates normally, and calculate the mean difference difference ΔDev; Obtain the tail exhaust hydrogen concentration HCon1 when the drain valve fails to close and operates and the tail exhaust hydrogen concentration HCon2 when it operates normally, and calculate the tail exhaust hydrogen concentration difference ΔHCon; Obtain tail exhaust hydrogen concentration HCon3 and deviation Dev3 in real time when the hydrogen fuel cell is working, and calculate hydrogen pressure compensation value PWM3 of the drain valve; Calculate and obtain in real time the difference between the hydrogen pressure compensation value PWM3 of the drain valve when the hydrogen fuel cell is working and the hydrogen pressure compensation value PWM1 when the drain valve is closed, and compare the difference with the hydrogen pressure compensation difference ΔPWM and P1 at the time T when the drain valve is opened, so as to judge the state of the drain valve; If the drain valve is in the open state, and the difference between the deviation Dev3 obtained in real time when the hydrogen fuel cell is working and the deviation Dev obtained when the drain valve is abnormal and operating normally is calculated, if the difference is greater than or equal to the deviation ΔDev, it is determined that the drain valve fails to open; If the drain valve is in closed state, and the difference between the tail exhaust hydrogen concentration HCon3 obtained in real time when the hydrogen fuel cell is working and the tail exhaust hydrogen concentration HCon obtained when the drain valve is abnormal and operating normally is calculated, if the difference is greater than or equal to the tail exhaust hydrogen concentration difference ΔHCon, it is determined that the drain valve has failed to close.

2. A method for diagnosing a fault of an anode drain valve of a hydrogen fuel cell according to claim 1, characterized in that: The "calculating and obtaining in real time the difference between the hydrogen pressure compensation value PWM3 of the drain valve when the hydrogen fuel cell is working and the hydrogen pressure compensation value PWM1 when the drain valve is closed, and comparing the difference with the hydrogen pressure compensation difference ΔPWM and P1 at the time T when the drain valve is opened, so as to judge the state of the drain valve" includes the steps of: Determine the state of the drain valve. If the difference between the hydrogen pressure compensation value PWM3 of the drain valve when the hydrogen fuel cell is working and the hydrogen pressure compensation value PWM1 when the drain valve is closed is less than or equal to P1, determine that the drain valve is in the open state. If the difference between the hydrogen pressure compensation value PWM3 of the drain valve when the hydrogen fuel cell is working and the hydrogen pressure compensation value PWM1 when the drain valve is closed is greater than or equal to the hydrogen pressure compensation difference ΔPWM at the time T when the drain valve is opened, the drain valve is determined to be in a closed state.

3. A method for diagnosing a fault of an anode drain valve of a hydrogen fuel cell according to claim 2, characterized in that: The PI is a preset value for comparing the magnitude relationship between the hydrogen pressure compensation value PWM3 and the hydrogen pressure compensation value PWM1.

4. A hydrogen fuel cell anode drain valve fault diagnosis system, characterized in that: During operation, the hydrogen fuel cell anode drain valve fault diagnosis method according to any one of claims 1 to 3 is run, wherein the diagnosis system comprises a data acquisition module, a data processing module and a status diagnosis module; The data acquisition module is used to collect data values ​​such as hydrogen pressure compensation value, deviation from the mean and tail exhaust hydrogen concentration; The data processing module is used to calculate the data value from the data acquisition module; The state processing module is used to determine whether the drain valve fails to open or close based on the calculated data value, and perform fault processing accordingly.

5. A hydrogen fuel cell anode drain valve fault diagnosis system according to claim 4, characterized in that: The data processing module includes a first processing module and a second processing module; The first processing module is used to calculate the difference of the hydrogen pressure compensation value; The second processing module is used to calculate the deviation from the mean and the tail exhaust hydrogen concentration value.

6. A hydrogen fuel cell anode drain valve fault diagnosis system according to claim 5, characterized in that: The state processing module includes a first diagnosis result module and a second diagnosis result module; The first diagnosis result module determines the state of the drain valve according to the first processing module; The second diagnosis result module obtains a status diagnosis result of the drain valve according to the judgment of the second processing module and the first diagnosis result module.

7. A hydrogen fuel cell anode drain valve fault diagnosis device, characterized in that: The diagnostic device comprises an air inlet channel, an air outlet channel and a battery stack, wherein the air inlet channel is connected to the cathode of the battery stack, and the anode of the battery stack is connected to the air outlet channel; Among them, the air intake channel includes a hydrogen proportional valve and a sensor assembly connected to the hydrogen proportional valve, the air outlet channel includes a water separator and a drain valve, the sensor assembly is connected to the cathode of the battery stack, one end of the water separator is connected to the anode of the battery stack, and the other end is connected to the drain valve.

8. A hydrogen fuel cell anode drain valve fault diagnosis device according to claim 7, characterized in that: The air intake passage also includes an ejector, one end of which is connected to the hydrogen proportional valve and the water separator, and the other end of which is connected to the sensor assembly.

9. A hydrogen fuel cell anode drain valve fault diagnosis device according to claim 8, characterized in that: The sensor assembly includes a pressure sensor and a temperature sensor connected to the pressure sensor, the pressure sensor is connected to the hydrogen proportional valve, and the temperature sensor is connected to the cathode of the battery stack.

10. A hydrogen fuel cell anode drain valve fault diagnosis device according to claim 7, characterized in that: The diagnostic device also includes a gas storage device and a tail exhaust treatment device, wherein the gas storage device is connected to the air inlet passage, and the tail exhaust treatment device is connected to the air outlet passage.

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