A method for quickly diagnosing a hydrogen deficiency fault of a stack, a fuel cell, a storage medium, and a computer

Abstract

The present application relates to the technical field of fuel cell, in particular to a kind of hydrogen deficiency fault quick diagnosis method of electric pile, fuel cell, storage medium and computer, the hydrogen deficiency fault quick diagnosis method of electric pile of the present application can quickly identify partial hydrogen deficiency fault of electric pile, and greatly improve the fault positioning efficiency, provide cause positioning help and the improvement direction of electric pile design for electric pile manufacturer;Avoid the occurrence of safety accidents such as vehicle breakdown, can repair fault piece in time, protect fuel cell electric pile, improve electric pile service life.

Description

Technical Field

[0001] This invention relates to the field of fuel cell technology, specifically to a method for rapid diagnosis of hydrogen shortage faults in fuel cell stacks, a fuel cell, a storage medium, and a computer. Background Technology

[0002] During operation, fuel cell engines may experience issues where one or more cells have low voltage performance, failing to meet power requirements and causing the vehicle to reduce load or even shut down, severely impacting customer experience.

[0003] During fuel cell operation, nitrogen accumulates at the anode, reducing the hydrogen concentration. Hydrogen purging affects fuel cell performance. After purging, the fuel cell level generally returns to the level at the end of the last purging. However, when the fuel system malfunctions and hydrogen cannot be purged normally, hydrogen shortage can cause reverse polarity of the stack, fatally damaging the performance of the electrocatalyst and significantly reducing the electrochemical active area. This results in internal hydrogen shortage, leading to poor fuel cell performance, inability to meet vehicle power requirements, and severely impacting the stack's lifespan. In severe cases, it can even cause vehicle breakdowns and serious safety issues. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to provide a method for quickly identifying hydrogen shortage inside the fuel cell stack, thereby avoiding the risk of the vehicle breaking down directly during driving. This method includes a fuel cell, a storage medium, and a computer.

[0005] To solve the above-mentioned technical problems, the first technical solution adopted by the present invention is as follows:

[0006] A rapid diagnosis method for hydrogen shortage fault in fuel cell stacks involves calibrating the hydrogen injection PWM difference of the fuel cell engine, testing and recording the nitrogen concentration value and the PWM of hydrogen injection at each current point, and performing the following steps when the average value of a single or multiple stack cells is detected to be less than Vx during fuel cell operation.

[0007] S1. Set the start time of the tail valve to t1 and the closing time to t2 during operation; at each operating point, the hydrogen injection PWM value is Ax calibration value during purging and Bx calibration value during non-purging.

[0008] S2. Detect ΔWx during fuel cell operation based on ΔWx calibration value = Ax calibration value - Bx calibration value. If the actual value of ΔWx < ΔWx calibration value / i, then detect the hydrogen inlet pressure P1. The target hydrogen inlet pressure is P2. If P1 ∈ P2 ± N1%, it proves that the hydrogen pressure is supplied normally, and the cause of insufficient hydrogen supply can be ruled out. Proceed to S3.

[0009] S3. Detect the AC impedance value of the fuel cell stack at low frequency. The actual detected value is R1. Compare R1 with the calibrated impedance range R2-R3. If R1>R2, then the cause of excessive liquid water is ruled out, and proceed to S4.

[0010] S4. Detect the nitrogen concentration entering the pile. The actual detection value is Z1. If Z1 < N2%, then the cause of excessive nitrogen concentration is ruled out, and proceed to S5.

[0011] S5. The abnormal hydrogen injection duty cycle is determined to be a tailpipe valve malfunction.

[0012] Furthermore, Vx is the lower limit of the protection threshold for the fuel cell.

[0013] Furthermore, the Ax calibration value is the average value at time t1; the Bx calibration value is the average value at time t2.

[0014] Furthermore, the x values ​​of the Ax calibration value and the Bx calibration value range from 1 to N, with 1 to N corresponding to different operating conditions.

[0015] Furthermore, i is a coefficient, the value of which is determined based on the consistency of hydrogen injection, upstream pressure fluctuations, demand flow fluctuations, and data acquisition errors.

[0016] Furthermore, N1 is determined based on the error of hydrogen pressure fluctuation.

[0017] Furthermore, N2 is the calibrated value of the nitrogen concentration in the fuel cell stack.

[0018] To solve the above-mentioned technical problems, the second technical solution adopted by the present invention is as follows:

[0019] A fuel cell that performs the above-described rapid diagnosis method for hydrogen shortage faults in the fuel cell stack.

[0020] To solve the above-mentioned technical problems, the third technical solution adopted by the present invention is as follows:

[0021] A storage medium storing a computer program, which, when executed by a processor, implements the aforementioned rapid diagnosis method for hydrogen deficiency faults in fuel cell stacks.

[0022] To solve the above-mentioned technical problems, the fourth technical solution adopted by the present invention is as follows:

[0023] A computer includes at least a memory and a processor, wherein the memory stores a computer program, and the processor implements the above-described rapid diagnosis method for hydrogen deficiency faults in fuel cell stacks when executing the computer program in the memory.

[0024] The beneficial effects of this invention are as follows: the rapid diagnosis method for hydrogen deficiency faults in fuel cell stacks can quickly identify partial hydrogen deficiency faults in fuel cell stacks and greatly improve the efficiency of fault location, providing fuel cell stack manufacturers with assistance in locating the cause and directions for improving fuel cell stack design; it can prevent vehicle breakdowns and safety accidents, repair faulty parts in a timely manner, protect fuel cell stacks, and improve the service life of fuel cell stacks. Attached Figure Description

[0025] Figure 1 This is a schematic diagram of a rapid diagnosis method for hydrogen deficiency faults in fuel cell stacks, according to a specific embodiment of the present invention. Detailed Implementation

[0026] To explain in detail the technical content, objectives, and effects of the present invention, the following description is provided in conjunction with the embodiments and accompanying drawings.

[0027] Example 1

[0028] Please refer to Figure 1 A rapid diagnostic method for hydrogen deficiency faults in fuel cell stacks.

[0029] The hydrogen injection PWM differential calibration of the fuel cell engine is performed. The nitrogen concentration value of the fuel cell and the PWM of hydrogen injection at each current point are tested and recorded. When the average value of a single or multiple cells of the fuel cell stack is detected to be less than Vx (Vx is the lower limit of the protection threshold of the fuel cell) during fuel cell operation, the following steps are performed for positioning.

[0030] Step 1: Set the start time of the tail valve to t1 and the closing time to t2 during operation;

[0031] Step 2: At each operating point, the hydrogen injection PWM value during purging is the Ax calibration value (average value over time t1), and the hydrogen injection PWM value during non-purging is the Bx calibration value (average value over time t2), where x is 1-N, corresponding to different operating points.

[0032] Step 3: △Wx calibration value = Ax calibration value - Bx calibration value (record the △Wx calibration value);

[0033] Step 4: Detect ΔWx during fuel cell operation. If the actual value of ΔWx is less than the calibrated value of ΔWx / i (i is a coefficient, the value of which needs to be determined based on the consistency of hydrogen injection, front-end pressure fluctuation, demand flow fluctuation, and data acquisition error), proceed to the next step.

[0034] Step 5: Detect the hydrogen inlet pressure P1. The target hydrogen inlet pressure is P2. If P1 ∈ P2 ± N1% (N1 is determined based on the error of hydrogen pressure fluctuation), it proves that the hydrogen pressure is supplied normally, and the cause of insufficient hydrogen supply can be ruled out. Proceed to the next step.

[0035] Step 6: Detect the AC impedance value of the fuel cell stack at low frequency. The actual measured value is R1. Compare R1 with the calibrated impedance range R2-R3. If R1 > R2, the cause of excessive liquid water can be ruled out, and proceed to the next step.

[0036] Step 7: Detect the nitrogen concentration of the fuel cell stack. The actual detection value is Z1. If Z1 < N2% (N2 is the calibrated value of nitrogen concentration of the fuel cell stack), the cause of excessive nitrogen concentration can be ruled out, and proceed to the next step.

[0037] Step 8: After troubleshooting through the above steps, it can be determined that the abnormal hydrogen injection duty cycle is due to a tailpipe valve malfunction.

[0038] Vx is determined by the vehicle's own characteristics;

[0039] t1 and t2 are empirical values ​​and should be adjusted according to different models and weather conditions;

[0040] Ax calibration value and Bx calibration value are measured values;

[0041] P2 is the preset / calibrated value set during vehicle production;

[0042] R2 and R3 are preset / calibrated values.

[0043] Example 2

[0044] A fuel cell that performs the rapid diagnosis method for hydrogen shortage faults in the fuel cell stack as described in Example 1.

[0045] Example 3

[0046] A storage medium storing a computer program, which, when executed by a processor, implements the rapid diagnosis method for hydrogen deficiency faults in fuel cell stacks as described in Embodiment 1.

[0047] Example 4

[0048] A computer includes at least a memory and a processor, wherein the memory stores a computer program, characterized in that the processor, when executing the computer program in the memory, implements the rapid diagnosis method for hydrogen deficiency faults in fuel cell stacks as described in Embodiment 1.

[0049] The above description is merely an embodiment of the present invention and does not limit the patent scope of the present invention. Any equivalent modifications made based on the content of the present invention specification and drawings, or direct or indirect applications in related technical fields, are similarly included within the patent protection scope of the present invention.

Claims

1. A rapid diagnostic method for hydrogen deficiency faults in fuel cell stacks, characterized in that, The hydrogen injection PWM differential calibration of the fuel cell engine is performed. The nitrogen concentration value of the fuel cell and the PWM of hydrogen injection at each current point are tested and recorded. When the average value of a single or multiple cells of the fuel cell stack is detected to be less than Vx during fuel cell operation, the following steps are performed. S1. Set the start time of the tail valve to t1 and the closing time to t2 during operation; at each operating point, the hydrogen injection PWM value is Ax calibration value during purging and Bx calibration value during non-purging. S2. Based on the calibration value of △Wx = calibration value of Ax - calibration value of Bx, detect △Wx during fuel cell operation. If the actual value of △Wx < calibration value of △Wx / i, then detect the hydrogen inlet pressure P1. The target hydrogen inlet pressure is P2. If P1 ∈ P2 ± N1%, it proves that the hydrogen pressure is supplied normally, and the cause of insufficient hydrogen supply can be ruled out. Then proceed to S3. S3. Detect the AC impedance value of the fuel cell stack at low frequency. The actual detected value is R1. Compare R1 with the calibrated impedance range R2-R3. If R1>R2, then the cause of excessive liquid water is ruled out, and proceed to S4. S4. Detect the nitrogen concentration entering the pile. The actual detection value is Z1. If Z1 < N2%, then the cause of excessive nitrogen concentration is ruled out, and proceed to S5. S5. The abnormal hydrogen injection duty cycle was determined to be a tailpipe valve malfunction. Wherein, Vx is the lower limit of the protection threshold of the fuel cell; Wherein, the Ax calibration value is the average value at time t1; the Bx calibration value is the average value at time t2; Wherein, i is a coefficient, the value of which is determined based on the consistency of hydrogen injection, front-end pressure fluctuation, demand flow fluctuation, and data acquisition error; Wherein, N1 is determined based on the error of hydrogen pressure fluctuation; Wherein, N2 is the calibrated value of nitrogen concentration in the fuel cell stack.

2. The rapid diagnosis method for hydrogen deficiency faults in fuel cell stacks according to claim 1, characterized in that, The x values ​​of the Ax calibration value and the Bx calibration value range from 1 to N, with 1 to N corresponding to different operating conditions.

3. A fuel cell, characterized in that, The fuel cell performs the rapid diagnosis method for hydrogen deficiency faults in the fuel cell stack as described in any one of claims 1-2.

4. A storage medium storing a computer program, characterized in that, When the computer program is executed by the processor, it implements the rapid diagnosis method for hydrogen deficiency faults in fuel cell stacks as described in any one of claims 1-2.

5. A computer, comprising at least a memory and a processor, wherein the memory stores a computer program, characterized in that, When the processor executes the computer program on the memory, it implements the rapid diagnosis method for hydrogen deficiency faults in fuel cell stacks as described in any one of claims 1-2.

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