Fuel cell drainage fault diagnosis method, device, vehicle and storage medium

Abstract

The present invention belongs to the field of vehicle technology, and discloses a fuel cell drainage fault diagnosis method, device, vehicle and storage medium. The fuel cell drainage fault diagnosis method determines whether a water flooding fault occurs in the fuel cell stack based on the drainage duration ratio of the drainage valve. After the drainage valve is opened, the drainage time timer is turned on. By obtaining the pressure at the fuel cell stack outlet before and after a unit time, the pressure change rate at the fuel cell stack outlet is calculated, and the size of the pressure change rate and the set change rate are judged. If the pressure change rate is not less than the set change rate, the drainage duration ratio is calculated, and the size of the drainage duration ratio and the set ratio are judged. If the drainage duration ratio is less than the set ratio, it indicates that the water content in the gas-water separator is low and the fuel cell stack is flooded. By detecting the time when a large pressure change rate occurs, it is determined whether the fuel cell stack is flooded, thereby avoiding the risk of misjudgment due to the inability to accurately control the preset valve opening time.

Description

Technical Field

[0001] The present invention relates to the field of vehicle technology, and in particular to a fuel cell drainage fault diagnosis method, device, vehicle and storage medium. Background Art

[0002] During operation, hydrogen fuel cells react at the cathode to generate water, which then permeates from the cathode to the anode, damaging the anode. To avoid this, a hydrogen circulation loop and a gas-water separation device are usually installed at the outlet of the fuel cell stack. The hydrogen circulation loop removes water from the fuel cell stack, and liquid water is separated in the gas-water separator. The drain valve connected to the gas-water separator is periodically opened to drain the water from the gas-water separator. However, in cases where the hydrogen circulation volume is small, the fuel cell stack is lower than the hydrogen pipeline, or the hydrogen channel is lower than the gas-water separator, the hydrogen may not be able to carry the liquid water from the fuel cell stack to the gas-water separator, causing flooding.

[0003] To address this issue, a prior art method for diagnosing fuel cell flooding has been developed. This method detects the difference between the hydrogen outlet pressure and the target pressure while the drain valve is open to determine if the fuel cell is flooded. If the difference exceeds a threshold, the fuel cell is considered flooded. The principle is that when the anode is flooded, the amount of water in the gas-water separator is low. When the drain valve is opened, a large amount of gas is discharged from the hydrogen pipeline, causing a sudden drop in pressure.

[0004] In reality, the amount of water generated by the anode is difficult to accurately predict, making it difficult to precisely control the preset valve opening time. This results in a brief exhaust phase after the drain valve opens, which can also cause a sudden drop in pressure, leading to a pressure differential reaching a threshold. Consequently, existing fuel cell flooding diagnosis methods cannot accurately determine whether flooding has occurred, and are prone to misdiagnosis. Summary of the Invention

[0005] According to one aspect of the present invention, the present invention provides a fuel cell drainage fault diagnosis method to solve the problem that the fuel cell flooding diagnosis method in the prior art cannot accurately determine whether flooding has occurred, which easily leads to misjudgment.

[0006] To achieve the above object, the present invention adopts the following technical solutions:

[0007] A fuel cell drainage fault diagnosis method, wherein the fuel cell includes a stack having a stack inlet and a stack outlet, the fuel cell also including a gas-water separator connected to the stack outlet and a drain valve connected to the gas-water separator, the drain valve being used to drain water from the gas-water separator;

[0008] The fuel cell drainage fault diagnosis method includes:

[0009] Obtaining the pressure at the outlet of the fuel cell stack;

[0010] Determining that a water flooding fault occurs in the fuel cell stack according to the ratio of the drainage duration of the drain valve; determining that a water flooding fault occurs in the fuel cell stack according to the ratio of the drainage duration of the drain valve includes:

[0011] Obtaining a set valve opening time of the drain valve;

[0012] Determining that the drain valve is open;

[0013] Turn on the drain timer;

[0014] Re-obtaining the pressure at the outlet of the stack after a unit time;

[0015] Calculating the pressure change rate at the outlet of the stack;

[0016] Determining the magnitude of the pressure change rate and a set change rate;

[0017] If the pressure change rate is not less than the set change rate, a drainage duration ratio is calculated, where the drainage duration ratio is the ratio of the drainage time timer reading to the set valve opening time;

[0018] Determining the size of the drainage duration ratio and the set ratio;

[0019] If the drainage duration ratio is less than the set ratio, it is determined that a water flooding fault has occurred in the fuel cell stack.

[0020] As a preferred solution of the fuel cell drainage fault diagnosis method, the set ratio range is 50%-60%.

[0021] As a preferred solution of the fuel cell drainage fault diagnosis method, if the pressure change rate is less than the set change rate, the pressure at the outlet of the stack is re-obtained after a unit time has passed.

[0022] As a preferred solution of the fuel cell drainage fault diagnosis method, the method further includes the following steps, which are performed simultaneously with determining that the fuel cell stack has a flooding fault based on the drainage duration ratio of the drainage valve:

[0023] Determining whether a water flooding fault occurs in the fuel cell stack according to the inlet and outlet pressure difference of the fuel cell stack; determining whether a water flooding fault occurs in the fuel cell stack according to the inlet and outlet pressure difference of the fuel cell stack includes:

[0024] Obtaining the pressure at the inlet end of the fuel cell stack;

[0025] Calculating an inlet and outlet pressure difference of the fuel cell stack, where the inlet and outlet pressure difference is the difference between the pressure at the inlet end of the fuel cell stack and the pressure at the outlet end of the fuel cell stack;

[0026] Determining the magnitude of the inlet and outlet pressure difference and the set pressure difference;

[0027] If the inlet and outlet pressure difference is not less than the set pressure difference, it is determined that the fuel cell stack has a water flooding fault.

[0028] As a preferred embodiment of the fuel cell drainage fault diagnosis method, the fuel cell further includes a hydrogen circulation pump having a pump input end connected to the gas-water separator and a pump output end connected to the fuel cell stack inlet end, and the hydrogen circulation pump is used to pump gas from the gas-water separator;

[0029] The fuel cell drainage fault diagnosis method further includes, after determining that a flooding fault occurs:

[0030] Execute system fault recovery; executing system fault recovery includes:

[0031] Increase the rotation speed of the hydrogen circulation pump.

[0032] As a preferred solution of the fuel cell drainage fault diagnosis method, executing system fault recovery also includes:

[0033] The output current of the battery stack is reduced.

[0034] As a preferred solution of the fuel cell drainage fault diagnosis method, the method further includes, after determining that a flooding fault has occurred:

[0035] A flood fault alarm is issued.

[0036] According to another aspect of the present invention, there is provided a fuel cell drainage fault diagnosis device, comprising:

[0037] A first stack outlet pressure acquisition module, configured to acquire the pressure at the stack outlet;

[0038] A flooding fault determination module is used to determine whether a flooding fault has occurred in the stack based on the drainage duration ratio of the drain valve. The flooding fault determination module includes:

[0039] A set valve opening time acquisition unit, used to acquire the set valve opening time of the drain valve;

[0040] a drain valve opening determination unit, configured to determine if the drain valve is open;

[0041] A drainage time timer opening unit, used for opening the drainage time timer;

[0042] a second stack outlet pressure acquiring unit, configured to reacquire the pressure at the stack outlet after a unit time;

[0043] a pressure change rate calculation unit, configured to calculate the pressure change rate at the outlet of the fuel cell stack;

[0044] A pressure change rate determination unit, configured to determine a difference between the pressure change rate and a set pressure change rate;

[0045] a drainage duration ratio calculation unit, configured to calculate the drainage duration ratio when the pressure change rate is not less than the set change rate;

[0046] The drainage duration ratio judgment unit is used to judge the size of the drainage duration ratio and the set ratio.

[0047] According to another aspect of the present invention, a vehicle is provided, comprising a fuel cell, the fuel cell comprising a stack having a stack inlet and a stack outlet, the fuel cell further comprising an air-water separator connected to the stack outlet, and a drain valve connected to the air-water separator, the drain valve being configured to drain water from the air-water separator;

[0048] Also includes:

[0049] ECU;

[0050] a pressure sensor, disposed at an outlet of the fuel cell stack, for detecting the pressure at the outlet of the fuel cell stack and sending the detected pressure at the outlet of the fuel cell stack to the ECU;

[0051] a memory for storing one or more programs;

[0052] When the one or more programs are executed by the ECU, the ECU controls the vehicle to implement the above-mentioned fuel cell drainage fault diagnosis method.

[0053] According to another aspect of the present invention, a storage medium is provided, on which a computer program is stored. When the program is executed by an ECU, the vehicle implements the above-mentioned fuel cell drainage fault diagnosis method.

[0054] The beneficial effects of the present invention are:

[0055] The present invention provides a fuel cell drain fault diagnosis method, device, vehicle, and storage medium. The method determines whether a stack flooding fault has occurred based on the drain valve's drain duration ratio. After the drain valve is opened, a drain timer is activated. The pressure at the stack outlet is obtained before and after a unit time, and the pressure change rate at the stack outlet is calculated. The pressure change rate is compared to a set pressure change rate. If the pressure change rate is not less than the set pressure change rate, the drain valve has entered the exhaust phase. The drain duration ratio is then calculated and compared to the set ratio. If the drain duration ratio is less than the set ratio, the drain valve has entered the exhaust phase too early after opening, indicating low water content in the gas-water separator and stack flooding. The present invention determines stack flooding by detecting the time of a large pressure change rate, avoiding the risk of misjudgment due to inaccurate control of the preset valve opening time. Furthermore, the fuel cell drain fault diagnosis method provided by the present invention can also be used to predict anode water production and optimize drain valve opening time. BRIEF DESCRIPTION OF THE DRAWINGS

[0056] Figure 1 is a schematic structural diagram of a fuel cell in an embodiment of the present invention;

[0057] Figure 2 The process of the fuel cell drainage fault diagnosis method in the embodiment of the present invention is as follows Figure 1 ;

[0058] Figure 3 The process of the fuel cell drainage fault diagnosis method in the embodiment of the present invention is as follows Figure 2 ;

[0059] Figure 4 2 is a schematic structural diagram of a fuel cell drainage fault diagnosis device according to an embodiment of the present invention;

[0060] Figure 5 2 is a schematic structural diagram of a vehicle in an embodiment of the present invention.

[0061] In the picture:

[0062] 1. Fuel cell stack; 2. Gas-water separator; 3. Drain valve; 4. Hydrogen circulation pump;

[0063] 300, first stack outlet pressure acquisition module; 310, flooding fault determination module; 3101, set valve opening time acquisition unit; 3102, drain valve opening determination unit; 3103, drain time timer opening unit; 3104, second stack outlet pressure acquisition unit; 3105, pressure change rate calculation unit; 3106, pressure change rate determination unit; 3107, drain duration ratio calculation unit; 3108, drain duration ratio determination unit;

[0064] 400 , ECU; 410 , fuel cell; 420 , pressure sensor; 430 , memory. DETAILED DESCRIPTION

[0065] The present invention will be further described in detail below with reference to the accompanying drawings and examples. It will be understood that the specific embodiments described herein are intended only to illustrate the present invention and are not intended to limit the present invention. It should also be noted that, for ease of description, the accompanying drawings only illustrate portions relevant to the present invention, not all structures.

[0066] In the description of the present invention, unless otherwise expressly specified or limited, the terms "connected," "connected," and "fixed" should be understood in a broad sense. For example, they may refer to fixed connections, detachable connections, or integration; mechanical connections or electrical connections; direct connections or indirect connections through an intermediate medium; and internal communication between two components or interaction between two components. Those skilled in the art will understand the specific meanings of the above terms in the present invention in specific circumstances.

[0067] In the present invention, unless otherwise expressly specified or limited, a first feature being "above" or "below" a second feature may include the first and second features being in direct contact, or may include the first and second features being in contact not directly but through another feature between them. Furthermore, a first feature being "above," "above," and "above" a second feature may include the first feature being directly above or obliquely above the second feature, or may simply mean that the first feature is higher in level than the second feature. A first feature being "below," "below," and "below" a second feature may include the first feature being directly below or obliquely below the second feature, or may simply mean that the first feature is lower in level than the second feature.

[0068] In the description of this embodiment, terms such as "upper," "lower," "left," and "right" are used to refer to positions or locations based on those shown in the accompanying drawings. These terms are intended solely to facilitate description and simplify operation, and are not intended to indicate or imply that the devices or components referred to must have, be constructed, or operate in a specific orientation. Therefore, they should not be construed as limitations on the present invention. Furthermore, the terms "first" and "second" are used solely for descriptive purposes and have no special meaning.

[0069] Example 1

[0070] To prevent flooding of hydrogen fuel cell stacks, the prior art provides a fuel cell flooding diagnosis method. This method determines whether the fuel cell is flooded by detecting the difference between the hydrogen outlet pressure and the target pressure while the drain valve is open. When the difference exceeds a threshold, the fuel cell is deemed flooded. However, because the amount of water generated by the anode is difficult to accurately predict, the preset valve opening time cannot be accurately controlled. This results in a short exhaust phase after the normal drainage process when the drain valve is opened. During this exhaust phase, the pressure also drops sharply, and the pressure differential reaches the threshold. Therefore, the prior art fuel cell flooding diagnosis method cannot accurately determine whether flooding has occurred, which can easily lead to misjudgment.

[0071] In response to the above problems, this embodiment provides a fuel cell drainage fault diagnosis method to solve the problem that the fuel cell flooding diagnosis method in the prior art cannot accurately determine whether flooding has occurred and is prone to misjudgment. It can be used for fuel cells and applied in the field of vehicle technology.

[0072] Reference Figure 1 The fuel cell drainage fault diagnosis method in this embodiment is implemented by a fuel cell 410. The fuel cell 410 includes a stack 1 having a stack inlet and a stack outlet. The fuel cell 410 also includes a gas-water separator 2 connected to the stack outlet and a drain valve 3 connected to the gas-water separator 2. The drain valve 3 is used to drain water from the gas-water separator 2. Optionally, the fuel cell 410 also includes a hydrogen circulation pipeline. The hydrogen circulation pipeline is provided with a hydrogen circulation pump 4. The input end of the hydrogen circulation pump 4 is connected to the gas-water separator 2 and is used to absorb gas from the gas-water separator 2. The output end of the hydrogen circulation pump 4 is connected to the stack inlet. The mixture of hydrogen and water discharged from the stack outlet enters the gas-water separator 2 for gas-water separation. Liquid water can be discharged through the drain valve 3, while the gas enters the hydrogen circulation pump 4 and, driven by the hydrogen circulation pump 4, re-enters the stack inlet to achieve hydrogen circulation and remove water from the stack 1 through the flow of hydrogen.

[0073] Reference Figure 2 The fuel cell drainage fault diagnosis method in this embodiment is performed by a fuel cell drainage fault diagnosis device, which can be implemented by software and / or hardware and integrated into the vehicle. Specifically, the fuel cell drainage fault diagnosis method includes the following steps.

[0074] S100: Obtaining the pressure at the outlet of the fuel cell stack.

[0075] Because the amount of water in the gas-water separator 2 is difficult to accurately predict, opening the drain valve 3 typically involves both a draining and an exhausting process. Therefore, pressure changes at the stack outlet can intuitively reflect whether the drain valve 3 is in the draining or exhausting process. When the anode is flooded, the amount of water in the gas-water separator 2 is low. Opening the drain valve 3 will discharge a large amount of gas from the hydrogen pipeline, causing a sudden drop in pressure, which means that the drain valve 3 will enter the exhausting process earlier.

[0076] Specifically, the pressure at the outlet of the fuel cell stack can be obtained by a pressure sensor 420 disposed at the outlet of the fuel cell stack.

[0077] After step S100, the occurrence of a flooding fault in the fuel cell stack 1 is determined based on the drainage duration ratio of the drain valve 3. Specifically, the determination of the occurrence of a flooding fault in the fuel cell stack 1 based on the drainage duration ratio of the drain valve 3 includes steps S110-S117.

[0078] S110: Obtain the set valve opening time of the drain valve 3.

[0079] The opening and closing of drain valve 3 is typically controlled independently by a program that periodically opens drain valve 3. Generally, the amount of water in air-water separator 2 needs to be predicted, and the set opening time of drain valve 3 is typically determined based on the predicted amount of water in air-water separator 2. The calculation and prediction methods for the set opening time of drain valve 3 are already known in the art, and the specific principles and calculation process will not be elaborated on here.

[0080] S111: Determine whether the drain valve 3 is open.

[0081] S112: Start the drainage time timer.

[0082] After the drain valve 3 is opened, the drain process begins. At this time, the drain time timer is turned on to start accumulating the duration of the drain process.

[0083] S113: After a unit time, the pressure at the outlet of the fuel cell stack is re-obtained.

[0084] The specific information can still be obtained through the pressure sensor 420 arranged at the outlet end of the fuel cell stack.

[0085] S114: Calculate the pressure change rate at the outlet of the fuel cell stack.

[0086] The pressure change rate at the stack outlet refers to the change in pressure at the stack outlet per unit time. First, calculate the difference between the newly acquired pressure at the stack outlet and the previous pressure at the stack outlet. The pressure change rate at the stack outlet is the ratio of this difference to the unit time. The unit time should be as short as possible to ensure that the calculated pressure change rate at the stack outlet is closer to the actual pressure drop rate.

[0087] S115: Determine the magnitude of the pressure change rate and the set change rate.

[0088] If the pressure change rate is not less than the set change rate, execute S116.

[0089] The set change rate is the maximum pressure change rate when the drain valve 3 drains water. If the pressure change rate is not less than the set change rate, it indicates that the pressure change rate at this time is too large and the drain valve 3 has entered the process of starting to exhaust.

[0090] The drainage timer reading at this point is the duration of the drainage process of drain valve 3. By reading the drainage timer, the precise time when drain valve 3 transitions from the drainage process to the exhaust process can be accurately determined, facilitating subsequent determination of flooding. This also helps researchers more intuitively understand the drainage and exhaust processes of drain valve 3, enabling prediction of anode water production and optimization of the drain valve 3 opening time.

[0091] S116: Calculate the drainage duration ratio.

[0092] The drainage duration ratio is the ratio of the drainage time timer reading at this time to the set valve opening time.

[0093] S117: Determine the size of the drainage duration ratio and the set ratio.

[0094] If the drainage duration ratio is less than the set ratio, it is determined that a flooding fault has occurred.

[0095] The set ratio is the ratio of the actual draining time of drain valve 3 to the total valve opening time of drain valve 3. If the draining duration ratio is less than the set ratio, it indicates that drain valve 3 has entered the exhaust process prematurely, indicating that the water in the anode cannot be drained smoothly, that is, a flooding fault has occurred. The program can then terminate. Alternatively, if the draining duration ratio is not less than the set ratio, it indicates that a flooding fault has not occurred, and the process can return to S100.

[0096] The principle for setting the set ratio is mainly based on the accuracy of the water amount prediction in the gas-water separator 2. Optionally, the set ratio ranges from 50% to 90%. Theoretically, if the water amount prediction in the gas-water separator 2 is completely accurate, the drain valve 3 will close just after the water is completely drained, and there will be no exhaust state. However, due to the low accuracy of the water amount prediction in the gas-water separator 2, it is necessary to consider appropriately lowering the set ratio. For example, in this embodiment, the set ratio is 50% to 60%, and preferably 50%. It is understandable that with the advancement of technology, the accuracy of the water amount prediction in the gas-water separator 2 may gradually improve, and in this case, the set ratio should be appropriately increased.

[0097] The fuel cell drainage fault diagnosis method provided in this embodiment determines whether the fuel cell stack 1 has a flooding fault based on the drainage duration ratio of the drainage valve 3. After the drainage valve 3 is opened, the drainage time timer is turned on. By obtaining the pressure at the fuel cell stack outlet before and after a unit time, the pressure change rate at the fuel cell stack outlet is calculated, and the size of the pressure change rate and the set change rate are determined. If the pressure change rate is not less than the set change rate, it indicates that the drain valve 3 has entered the exhaust stage at this time. The drainage duration ratio is calculated and the size of the drainage duration ratio and the set ratio are determined. If the drainage duration ratio is less than the set ratio, it means that the drain valve 3 enters the exhaust stage too early after opening, indicating that the water content in the gas-water separator 2 is low and the fuel cell stack 1 is flooded. This embodiment determines whether the fuel cell stack 1 is flooded by detecting the time when a large pressure change rate occurs, avoiding the risk of misjudgment due to the inability to accurately control the preset valve opening time.

[0098] Example 2

[0099] The fuel cell drainage fault diagnosis method provided in this embodiment is specific based on the above embodiment 1. Figure 3 , a fuel cell drainage fault diagnosis method includes the following steps.

[0100] S200: Obtaining the pressure at the outlet of the fuel cell stack.

[0101] The pressure change at the outlet of the stack can reflect whether the drain valve 3 is in the draining process or the exhausting process. In addition, when the stack 1 is flooded, the pressure difference between the stack inlet and the stack outlet often changes.

[0102] After step S200, the process of determining whether the fuel cell stack 1 has been flooded is performed based on the ratio of the drainage durations of the drain valve 3, and simultaneously determining whether the fuel cell stack 1 has been flooded is performed based on the inlet and outlet pressure difference of the fuel cell stack 1. The process of determining whether the fuel cell stack 1 has been flooded based on the inlet and outlet pressure difference of the fuel cell stack 1 includes steps S201-S203, and the process of determining whether the fuel cell stack 1 has been flooded based on the ratio of the drainage durations of the drain valve 3 includes steps S210-S217.

[0103] S201: Obtain the pressure at the inlet end of the fuel cell stack.

[0104] Specifically, it can be obtained through an inlet pressure sensor arranged at the inlet of the fuel cell stack.

[0105] S202: Calculate the inlet and outlet pressure difference of the fuel cell stack 1.

[0106] The inlet and outlet pressure difference is the difference between the pressure at the inlet of the fuel cell stack and the pressure at the outlet of the fuel cell stack.

[0107] S203: Determine the magnitude of the inlet and outlet pressure difference and the set pressure difference.

[0108] If the inlet and outlet pressure difference is not less than the set pressure difference, it is determined that the fuel cell stack 1 has a water flooding fault.

[0109] The set pressure differential is the maximum allowable pressure difference between the stack inlet and outlet when no flooding occurs. If the inlet / outlet pressure differential is not less than the set pressure differential, it indicates that the pressure differential is too large, confirming that a flooding fault has occurred in stack 1.

[0110] S210: Obtain the set valve opening time of the drain valve 3.

[0111] S211: Determine whether the drain valve 3 is open.

[0112] S212: Start the drainage time timer.

[0113] S213: After a unit time, the pressure at the outlet of the fuel cell stack is re-obtained.

[0114] S214: Calculate the pressure change rate at the outlet of the fuel cell stack.

[0115] S215: Determine the magnitude of the pressure change rate and the set change rate.

[0116] If the pressure change rate is not less than the set change rate, execute S216. If the pressure change rate is less than the set change rate, return to S213 and recalculate the pressure change rate at the stack outlet. When drain valve 3 is in the drainage process, the pressure change rate at the stack outlet is generally less than the set change rate. However, after drain valve 3 enters the exhaust process, the pressure change rate at the stack outlet will instantly increase and reach the set change rate.

[0117] S216: Calculate the drainage duration ratio.

[0118] S217: Determine the size of the drainage duration ratio and the set ratio.

[0119] If the drainage duration ratio is less than the set ratio, it is determined that a flooding fault has occurred.

[0120] In step S203 and step S217, if no one step determines that a flood fault has occurred, the following steps may be continued.

[0121] S220: A flood fault alarm is issued.

[0122] Flood fault alarms include sound and light signals.

[0123] S230: Execute system fault recovery.

[0124] Specifically, step S230 includes:

[0125] The rotation speed of the hydrogen circulation pump 4 is increased to increase the air intake of the fuel cell stack 1 , and water can be taken out of the fuel cell stack 1 by increasing the circulating air intake.

[0126] Reducing the output current of the battery stack 1 can reduce the generation of water, which also helps to solve the flooding problem.

[0127] The fuel cell drain fault diagnosis method provided in this embodiment not only determines whether a fuel cell stack 1 has experienced a flooding fault based on the drain valve 3 drainage duration ratio, but also provides a method for determining whether a fuel cell stack 1 has experienced a flooding fault based on the inlet and outlet pressure differential of the fuel cell stack 1, thus avoiding the uncertainty of a single diagnostic method. After determining that a flooding fault has occurred, an alarm is issued and system fault recovery is automatically executed to attempt to automatically repair the flooding fault.

[0128] Example 3

[0129] This embodiment provides a fuel cell water drainage fault diagnosis device, which can execute the fuel cell water drainage fault diagnosis method described in the above embodiment.

[0130] Reference Figure 4 The fuel cell drainage fault diagnosis device includes a first stack outlet pressure acquisition module 300 and a water flooding fault determination module 310, wherein the water flooding fault determination module 310 is used to determine whether the stack has a water flooding fault based on the drainage duration ratio of the drainage valve, and includes a valve opening time acquisition unit 3101, a drainage valve opening determination unit 3102, a drainage time timer opening unit 3103, a second stack outlet pressure acquisition unit 3104, a pressure change rate calculation unit 3105, a pressure change rate judgment unit 3106, a drainage duration ratio calculation unit 3107 and a drainage duration ratio judgment unit 3108.

[0131] Among them, the first stack outlet pressure acquisition module 300 is used to obtain the pressure at the stack outlet; the set valve opening time acquisition unit 3101 is used to obtain the set valve opening time of the drain valve; the drain valve opening determination unit 3102 is used to determine whether the drain valve is open; the drain time timer opening unit 3103 is used to open the drain time timer; the second stack outlet pressure acquisition unit 3104 is used to re-acquire the pressure at the stack outlet after a unit time; the pressure change rate calculation unit 3105 is used to calculate the pressure change rate at the stack outlet; the pressure change rate judgment unit 3106 is used to judge the size of the pressure change rate and the set change rate; the drainage duration ratio calculation unit 3107 is used to calculate the drainage duration ratio when the pressure change rate is not less than the set change rate; the drainage duration ratio judgment unit 3108 is used to judge the size of the drainage duration ratio and the set ratio.

[0132] The fuel cell drain fault diagnosis device provided in this embodiment obtains the pressure at the stack outlet through the first stack outlet pressure acquisition module 300; obtains the set valve opening time of the drain valve through the set valve opening time acquisition unit 3101; determines the drain valve opening through the drain valve opening determination unit 3102; turns on the drain time timer through the drain time timer opening unit 3103; re-acquires the pressure at the stack outlet after a unit time through the second stack outlet pressure acquisition unit 3104; calculates the pressure change rate at the stack outlet through the pressure change rate calculation unit 3105; determines the difference between the pressure change rate and the set change rate through the pressure change rate judgment unit 3106; when the pressure change rate is not less than the set change rate, calculates the drain duration ratio through the drain duration ratio calculation unit 3107; and determines the difference between the drain duration ratio and the set ratio through the drain duration ratio judgment unit 3108. The fuel cell drain fault diagnosis device can determine whether the stack is flooded by detecting the time when a large pressure change rate occurs, thereby avoiding the risk of misjudgment due to the inability to accurately control the preset valve opening time.

[0133] Example 4

[0134] This embodiment provides a vehicle including a fuel cell 410. The fuel cell 410 includes a stack 1 having a stack inlet and a stack outlet. The fuel cell 410 also includes a gas-water separator 2 connected to the stack outlet and a drain valve 3 connected to the gas-water separator 2. The drain valve 3 is used to drain water from the gas-water separator 2. The vehicle also includes an ECU 400, a pressure sensor 420, and a memory 430. The ECU 400, the fuel cell 410, the pressure sensor 420, and the memory 430 may be connected via a bus.

[0135] Specifically, the pressure sensor 420 is disposed at the outlet of the fuel cell stack, and is used to detect the pressure at the outlet of the fuel cell stack, and send the detected pressure at the outlet of the fuel cell stack to the ECU 400 .

[0136] Memory 430, as a computer-readable storage medium, can be used to store software programs, computer-executable programs, and modules, such as the program instructions / modules corresponding to the fuel cell water drainage fault diagnosis method in the embodiments of the present invention. ECU 400 executes the software programs, instructions, and modules stored in memory 430 to perform various vehicle functions and data processing, thereby implementing the fuel cell water drainage fault diagnosis method in the embodiments described above.

[0137] Memory 430 primarily includes a program storage area and a data storage area. The program storage area can store an operating system and at least one application required for a function; the data storage area can store data generated based on the terminal's usage. Furthermore, memory 430 can include high-speed random access memory and non-volatile memory, such as at least one disk storage device, flash memory device, or other non-volatile solid-state memory device. In some instances, memory 430 may further include memory 430 located remotely from ECU 400, which can be connected to the vehicle via a network. Examples of such networks include, but are not limited to, the Internet, corporate intranets, local area networks, mobile communication networks, and combinations thereof.

[0138] The vehicle provided in the fourth embodiment of the present invention and the fuel cell drainage fault diagnosis method provided in the above embodiment belong to the same inventive concept. The technical details not described in detail in this embodiment can be referred to the above embodiment, and this embodiment has the same beneficial effects as executing the fuel cell drainage fault diagnosis method.

[0139] Example 5

[0140] The fifth embodiment of the present invention further provides a storage medium on which a computer program is stored. When the program is executed by the ECU, the vehicle implements the fuel cell drainage fault diagnosis method as described in the above embodiment of the present invention.

[0141] Of course, the storage medium containing computer-executable instructions provided in the embodiment of the present invention is not limited to the operations in the fuel cell drainage fault diagnosis method described above, but can also execute related operations in the fuel cell drainage fault diagnosis device provided in the embodiment of the present invention, and has corresponding functions and beneficial effects.

[0142] Through the above description of the implementation methods, those skilled in the art can clearly understand that the present invention can be implemented with the help of software and necessary general-purpose hardware. Of course, it can also be implemented by hardware, but in many cases the former is a better implementation method. Based on this understanding, the technical solution of the present invention, or the part that contributes to the existing technology, can be embodied in the form of a software product. The computer software product can be stored in a computer-readable storage medium, such as a computer floppy disk, read-only memory (ROM), random access memory (RAM), flash memory (FLASH), hard disk or optical disk, etc., and includes a number of instructions for enabling a computer device (which can be a robot, personal computer, server, or network device, etc.) to execute the fuel cell drainage fault diagnosis method described in each embodiment of the present invention.

[0143] Obviously, the above embodiments of the present invention are merely examples for the purpose of clearly illustrating the present invention and are not intended to limit the embodiments of the present invention. A person skilled in the art would be able to make various obvious changes, readjustments, and substitutions without departing from the scope of protection of the present invention. It is not necessary and impossible to enumerate all embodiments here. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention shall be included within the scope of protection of the claims of the present invention.

Claims

1. A method for diagnosing a fuel cell drainage fault, wherein the fuel cell includes a stack having a stack inlet and a stack outlet, a gas-water separator connected to the stack outlet, and a drain valve connected to the gas-water separator, the drain valve being used to drain water from the gas-water separator; It is characterized by: The fuel cell drainage fault diagnosis method includes: Obtaining the pressure at the outlet of the fuel cell stack; Determining that a water flooding fault occurs in the fuel cell stack according to the ratio of the drainage duration of the drain valve; determining that a water flooding fault occurs in the fuel cell stack according to the ratio of the drainage duration of the drain valve includes: Obtaining a set valve opening time of the drain valve; Determining that the drain valve is open; Turn on the drain timer; Re-obtaining the pressure at the outlet of the stack after a unit time; Calculating the pressure change rate at the outlet of the stack; Determining the magnitude of the pressure change rate and a set change rate; If the pressure change rate is not less than the set change rate, a drainage duration ratio is calculated, where the drainage duration ratio is the ratio of the drainage time timer reading to the set valve opening time; Determining the size of the drainage duration ratio and the set ratio; If the drainage duration ratio is less than the set ratio, it is determined that a water flooding fault has occurred in the fuel cell stack.

2. The fuel cell drainage fault diagnosis method according to claim 1, characterized in that: The set ratio range is 50%-60%.

3. The fuel cell drainage fault diagnosis method according to claim 1, characterized in that: If the pressure change rate is less than the set change rate, the pressure at the outlet of the stack is obtained again after a unit time has passed.

4. The fuel cell drainage fault diagnosis method according to claim 1, characterized in that: The method further includes the following steps, which are performed simultaneously with determining that a water flooding fault has occurred in the fuel cell stack based on the drainage duration ratio of the drainage valve: determining, based on the inlet and outlet pressure difference of the fuel cell stack, that a water flooding fault has occurred in the fuel cell stack; Determining whether the fuel cell stack is flooded according to the inlet and outlet pressure difference of the fuel cell stack includes: Obtaining the pressure at the inlet end of the fuel cell stack; Calculating an inlet and outlet pressure difference of the fuel cell stack, where the inlet and outlet pressure difference is the difference between the pressure at the inlet end of the fuel cell stack and the pressure at the outlet end of the fuel cell stack; Determining the magnitude of the inlet and outlet pressure difference and the set pressure difference; If the inlet and outlet pressure difference is not less than the set pressure difference, it is determined that the fuel cell stack has a water flooding fault.

5. The fuel cell drainage fault diagnosis method according to any one of claims 1 to 4, characterized in that: The fuel cell further includes a hydrogen circulation pump having a pump input end connected to the gas-water separator and a pump output end connected to the fuel cell stack inlet end, and the hydrogen circulation pump is used to pump gas from the gas-water separator; The fuel cell drainage fault diagnosis method further includes, after determining that a flooding fault occurs: Execute system fault recovery; executing system fault recovery includes: Increase the rotation speed of the hydrogen circulation pump.

6. The fuel cell drainage fault diagnosis method according to claim 5, characterized in that: Performing system fault recovery also includes: The output current of the battery stack is reduced.

7. The fuel cell drainage fault diagnosis method according to any one of claims 1 to 4, characterized in that: Also included after a flooding fault is determined to have occurred: A flood fault alarm is issued.

8. A fuel cell drainage fault diagnosis device, characterized in that: include: A first stack outlet pressure acquisition module, configured to acquire the pressure at the stack outlet; A flooding fault determination module is used to determine whether a flooding fault has occurred in the stack based on the drainage duration ratio of the drain valve. The flooding fault determination module includes: A set valve opening time acquisition unit, used to acquire the set valve opening time of the drain valve; a drain valve opening determination unit, configured to determine if the drain valve is open; A drainage time timer opening unit, used for opening the drainage time timer; a second stack outlet pressure acquiring unit, configured to reacquire the pressure at the stack outlet after a unit time; a pressure change rate calculation unit, configured to calculate the pressure change rate at the outlet of the fuel cell stack; A pressure change rate determination unit, configured to determine a difference between the pressure change rate and a set pressure change rate; a drainage duration ratio calculation unit, configured to calculate the drainage duration ratio when the pressure change rate is not less than the set change rate; The drainage duration ratio judgment unit is used to judge the size of the drainage duration ratio and the set ratio.

9. A vehicle comprising a fuel cell, the fuel cell comprising a stack having a stack inlet and a stack outlet, the fuel cell further comprising a gas-water separator connected to the stack outlet and a drain valve connected to the gas-water separator, the drain valve being configured to drain water from the gas-water separator; It is characterized by: Also includes: ECU; a pressure sensor, disposed at an outlet of the fuel cell stack, for detecting the pressure at the outlet of the fuel cell stack and sending the detected pressure at the outlet of the fuel cell stack to the ECU; a memory for storing one or more programs; When the one or more programs are executed by the ECU, the ECU controls the vehicle to implement the fuel cell water drainage fault diagnosis method according to any one of claims 1 to 7.

10. A storage medium having a computer program stored thereon, characterized in that When the program is executed by the ECU, the vehicle implements the fuel cell water drainage fault diagnosis method according to any one of claims 1 to 7.

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