Apparatus and method for diagnosing faults in a fuel cell system

Abstract

The present disclosure relates to an apparatus and method for diagnosing faults in a fuel cell system. To prevent degradation of a fuel cell stack due to an abnormal supply of hydrogen, the apparatus includes: a first pressure sensor for measuring the pressure of the hydrogen supplied to the fuel cell stack; a second pressure sensor for measuring the pressure of the hydrogen supplied to the fuel cell stack; and a controller for first diagnosing the hydrogen supply status based on a first pressure value measured by the first pressure sensor and a second pressure value measured by the second pressure sensor, and further diagnosing the hydrogen supply status based on the absolute value of the difference between the first pressure value and the second pressure value.

Description

[0001] Cross-citation to related applications

[0002] This application claims the benefit of priority from Korean Patent Application No. 10-2019-0144607, filed on November 12, 2019, in the Korean Intellectual Property Office, the entire contents of which are incorporated herein by reference. Technical Field

[0003] The present disclosure relates to a technology for diagnosing a fault in a fuel cell system installed in a fuel cell electric vehicle. Background Art

[0004] A fuel cell is a type of generator that converts the chemical energy of a fuel into electrical energy through an electrochemical reaction within the fuel cell stack, rather than converting chemical energy into heat through combustion. Fuel cells can provide electricity for industrial, domestic, and vehicle applications, and are also used as a power source for small electric electronic devices, particularly portable devices.

[0005] Currently, proton exchange membrane fuel cells (PEMFCs), also known as polymer electrolyte membrane fuel cells, are being widely researched as a power source for driving vehicles. Due to their low operating temperature, PEMFCs have fast startup times and rapid power conversion response times.

[0006] The PEMFC includes: a membrane electrode assembly (MEA) having catalyst electrode layers in which an electrochemical reaction occurs and attached to opposite sides of a solid polymer electrolyte membrane through which hydrogen ions move; a gas diffusion layer (GDL) for uniformly distributing the reaction gas and transmitting the generated electrical energy; gaskets and fastening members that prevent leakage of the reaction gas and cooling water and maintain appropriate fastening pressure; and bipolar plates that allow the reaction gas and cooling water to move therethrough.

[0007] When assembling a fuel cell stack using a unit cell configuration, the main components, the MEA and GDL, are located at the innermost position of the cell. The MEA includes catalyst electrode layers, namely the anode and cathode, attached to opposing surfaces of the polymer electrolyte membrane and coated with a catalyst to allow hydrogen and oxygen to react with each other. The GDL, gasket, and other components are stacked on the outside where the anode and cathode are located.

[0008] Bipolar plates having flow fields formed therein, which supply reactant gases (hydrogen as fuel and oxygen or air as oxidant) and allow cooling water to pass therethrough, are located outside the GDL.

[0009] After stacking a plurality of unit cells having the above configuration, current collectors, insulating plates, and end plates for supporting the stacked cells are coupled to the outermost portion of the fuel cell stack. The unit cells are repeatedly stacked and assembled between the end plates to form a fuel cell stack.

[0010] To achieve the required electric potential for a vehicle, cells corresponding to the required potential must be stacked, and this stack of cells is called a stack. For example, the potential generated by a single cell is approximately 1.3V, and to generate the power to drive a vehicle, multiple cells can be stacked in series.

[0011] Meanwhile, the pressure of hydrogen gas supplied to the fuel cell stack is one of the very important control factors that determine the performance of the fuel cell system.

[0012] For example, when high-pressure hydrogen is supplied to a fuel cell stack, poor fuel economy can result from hydrogen passing through the oxygen electrode. Conversely, when low-pressure hydrogen is supplied to the fuel cell stack, the required vehicle output power is not achieved, and catalyst damage can accelerate stack degradation. For reference, hydrogen that passes through the oxygen electrode is released into the air without any reaction.

[0013] Conventional techniques for diagnosing faults in fuel cell systems do not verify the pressure values ​​measured by multiple hydrogen pressure sensors and diagnose faults in the fuel cell system by using deviations in the pressure values. Therefore, conventional techniques may incorrectly diagnose a fuel cell system as having a fault even when the fuel cell system is not faulty.

[0014] The information disclosed in this Background section is only for enhancement of understanding of the background of the disclosure and may contain information that does not form the prior art already known to a person skilled in the art. Summary of the Invention

[0015] The present disclosure has been made to solve the above-mentioned problems occurring in the prior art while the advantages achieved by the prior art remain unchanged.

[0016] One aspect of the present disclosure provides an apparatus and method for diagnosing faults in a fuel cell system, wherein the apparatus and method diagnose whether hydrogen is smoothly supplied to a fuel cell stack by using a plurality of hydrogen pressure sensors and determine whether to shut down the fuel cell system based on the diagnosis result, thereby preventing degradation of the fuel cell stack due to abnormal supply of hydrogen.

[0017] The technical problems to be solved by the present invention are not limited to the above-mentioned problems, and any other technical problems not mentioned herein will be clearly understood by those skilled in the art to which the present disclosure pertains from the following description.

[0018] According to one aspect of the present disclosure, an apparatus for diagnosing faults in a fuel cell system includes: a first pressure sensor for measuring the pressure of hydrogen supplied to a fuel cell stack; a second pressure sensor for measuring the pressure of hydrogen supplied to the fuel cell stack; and a controller for first diagnosing the supply status of hydrogen based on a first pressure value measured by the first pressure sensor and a second pressure value measured by the second pressure sensor, and further diagnosing the supply status of hydrogen based on the absolute value of the difference between the first pressure value and the second pressure value.

[0019] When the minimum value of the first pressure value and the second pressure value is greater than or equal to the first threshold value, the controller may initially diagnose the supply state of the hydrogen gas as normal.

[0020] When the minimum value is less than the first threshold and the absolute value exceeds the second threshold, the controller may further diagnose the supply state of hydrogen as abnormal.

[0021] When a state in which the minimum value is less than a first threshold value and the absolute value exceeds a second threshold value continues for more than a first threshold time, the controller may further diagnose the supply state of hydrogen gas as abnormal.

[0022] During startup of the fuel cell system, when the hydrogen supply system is operating normally, the controller may start the fuel cell system when the target pressure value minus the current pressure value is less than a third threshold value. The current pressure value may be any one of the first pressure value, the second pressure value, a maximum of the first pressure value and the second pressure value, and an average of the first pressure value and the second pressure value.

[0023] During startup of the fuel cell system, the controller may start the fuel cell system when there is no abnormality in the hydrogen supply system within a second threshold time and a state in which the target pressure value minus the current pressure value is less than a third threshold value continues for a third threshold time. The current pressure value may be any one of the first pressure value, the second pressure value, a maximum of the first pressure value and the second pressure value, and an average of the first pressure value and the second pressure value.

[0024] The controller can diagnose the supply status of hydrogen based on the moving average of the difference between the first pressure value and the second pressure value during operation of the fuel cell system. When the supply status of hydrogen is diagnosed as abnormal, the controller can calculate the final target pressure value based on Equation 1.

[0025] According to another aspect of the present disclosure, a method for diagnosing faults in a fuel cell system includes: measuring the pressure of hydrogen supplied to the fuel cell stack by a first pressure sensor; measuring the pressure of hydrogen supplied to the fuel cell stack by a second pressure sensor; first diagnosing the supply status of hydrogen by a controller based on a first pressure value measured by the first pressure sensor and a second pressure value measured by the second pressure sensor; and further diagnosing the supply status of hydrogen by the controller based on the absolute value of the difference between the first pressure value and the second pressure value.

[0026] First diagnosing the supply state of hydrogen gas may include first diagnosing the supply state of hydrogen gas as normal when a minimum value of the first pressure value and the second pressure value is greater than or equal to a first threshold value.

[0027] Further diagnosing the supply state of hydrogen gas may include diagnosing the supply state of hydrogen gas as abnormal when the minimum value is less than a first threshold value and the absolute value exceeds a second threshold value.

[0028] Further diagnosing the supply state of hydrogen may include diagnosing the supply state of hydrogen as abnormal when a state in which the minimum value is less than a first threshold value and the absolute value exceeds a second threshold value continues for more than a first threshold time.

[0029] The method may further include starting the fuel cell system when, during startup of the fuel cell system, the hydrogen supply system is operating normally and the target pressure value minus the current pressure value is less than a third threshold value. The current pressure value may be any one of the first pressure value, the second pressure value, a maximum of the first pressure value and the second pressure value, and an average of the first pressure value and the second pressure value.

[0030] The method may further include starting the fuel cell system when, during startup of the fuel cell system, there is no abnormality in the hydrogen supply system within a second threshold time and a state in which the target pressure value minus the current pressure value is less than a third threshold value continues for a third threshold time. The current pressure value may be any one of the first pressure value, the second pressure value, a maximum of the first pressure value and the second pressure value, and an average of the first pressure value and the second pressure value.

[0031] The method may further include diagnosing a hydrogen supply status based on a moving average of a difference between a first pressure value and a second pressure value during operation of the fuel cell system. In this case, when the hydrogen supply status is diagnosed as abnormal, a final target pressure value may be calculated based on Equation 1. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] The above and other objects, features and advantages of the present disclosure will become more apparent from the following detailed description taken in conjunction with the accompanying drawings:

[0033] Figure 1is a diagram showing the structure of a fuel cell system to which one embodiment of the present disclosure is applied;

[0034] Figure 2 is a view showing a configuration of an apparatus for diagnosing a fault in a fuel cell system according to one embodiment of the present disclosure;

[0035] Figure 3 is a first flow chart illustrating a method for diagnosing a fault in a fuel cell system according to one embodiment of the present disclosure;

[0036] Figure 4 is a second flow chart illustrating a method for diagnosing a fault in a fuel cell system according to one embodiment of the present disclosure;

[0037] Figure 5 is a third flow chart illustrating a method for diagnosing a fault in a fuel cell system according to one embodiment of the present disclosure; and

[0038] Figure 6 is a block diagram illustrating a computing system for executing a fault diagnosis method for a fuel cell system according to one embodiment of the present disclosure. DETAILED DESCRIPTION

[0039] Hereinafter, some embodiments of the present disclosure will be described in detail with reference to the exemplary drawings. In adding reference numerals to the components of each drawing, it should be noted that the same or equivalent components are designated by the same reference numerals even when they are shown in other drawings. Furthermore, in describing the embodiments of the present disclosure, detailed descriptions of well-known features or functions will be excluded in order not to unnecessarily obscure the main idea of ​​the present disclosure.

[0040] In describing components according to embodiments of the present disclosure, terms such as first, second, "A", "B", (a), (b), etc. may be used. These terms are intended only to distinguish one component from another, and the terms do not limit the nature, sequence, or order of the components. Unless otherwise defined, all terms (including technical or scientific terms) used herein have the same meaning as commonly understood by those skilled in the art to which the present disclosure belongs. Terms such as those defined in commonly used dictionaries should be interpreted as having the same meaning as in the context of the relevant technical field and should not be interpreted as having an ideal or overly formal meaning unless expressly defined as having such a meaning in this application.

[0041] Figure 1 It is a view showing the structure of a fuel cell system to which one embodiment of the present disclosure is applied, and focuses on a hydrogen supply system consistent with the spirit of one embodiment of the present disclosure.

[0042] like Figure 1 As shown, a fuel cell system to which one embodiment of the present disclosure is applied may include an FBV 100 , an FSV 110 , an FEJ 120 , a first pressure sensor 130 , a second pressure sensor 131 , a fuel cell stack (FCS) 140 , an FPV 150 , an FWT 160 , an FL20 170 , and an FDV 180 .

[0043] A fuel shutoff valve (FBV) 100 serves to shut off the supply of hydrogen to the FCS 140 .

[0044] A fuel supply valve (FSV) 110 serves to regulate the pressure of hydrogen gas supplied to the FCS 140 .

[0045] The fuel injector (FEJ) 120 serves to recirculate hydrogen gas at the fuel electrode.

[0046] The first pressure sensor 130 is used to measure the pressure of hydrogen gas supplied to the FCS 140 .

[0047] The second pressure sensor 131 is used to measure the pressure of hydrogen gas supplied to the FCS 140 .

[0048] The FCS 140 generates electricity using a chemical reaction of hydrogen and oxygen.

[0049] The FPV 150 serves as a fuel line bleed valve to discharge condensed water and impurities from the fuel electrode in the FCS 140 .

[0050] The FWT 160, which serves as a fuel line water trap, is used to store water.

[0051] The FL20 170 , which is a fuel line water level sensor, serves to measure the level of water stored in the FWT 160 .

[0052] The FDV 180 , which is a fuel line drain valve, serves to drain water stored in the FWT 160 .

[0053] Figure 2 is a view showing a configuration of an apparatus for diagnosing a fault in a fuel cell system according to one embodiment of the present disclosure.

[0054] like Figure 2 As shown, a fault diagnosis apparatus 10 for a fuel cell system according to an embodiment of the present disclosure may include a storage device 11, a display 12, and a controller 13. Depending on how the fault diagnosis apparatus 10 for a fuel cell system according to an embodiment of the present disclosure is implemented, the components may be combined together to form a single entity, or some components may be omitted.

[0055] The components will be described below. First, the storage device 11 may store various types of logic, algorithms, and programs required for diagnosing whether hydrogen is being stably supplied to the FCS 140 using the plurality of pressure sensors 130 and 131, and determining whether to shut down the fuel cell system based on the diagnosis results. Here, shutting down the fuel cell system means blocking the supply of hydrogen to the FCS 140, thereby halting the operation of the FCS 140.

[0056] The storage device 11 may store a first threshold value P1 for the pressure value measured by the first pressure sensor 130 or the pressure value measured by the second pressure sensor 131. Here, the first threshold value P1 is preferably set to a pressure value (eg, 50 kPa) that is difficult to measure physically.

[0057] The storage device 11 may store a second threshold value P2 for a difference between the pressure value measured by the first pressure sensor 130 and the pressure value measured by the second pressure sensor 131. Here, the second threshold value P2 is preferably set to a pressure value (e.g., 30 kPa) at which excessive hydrogen may be supplied to the FCS 140 due to the difference between the pressure value measured by the first pressure sensor 130 and the pressure value measured by the second pressure sensor 131.

[0058] The storage device 11 may store a first threshold time T1 (e.g., 200 ms) for the time when a specific condition is satisfied. If the first threshold time T1 is too long, excessive hydrogen supply to the FCS 140 cannot be prevented, and if it is too short, misdiagnosis may occur.

[0059] In addition, the storage device 11 may store a second threshold time T2 for the time during which hydrogen gas is stably supplied during the startup of the fuel cell system. Here, for example, the second threshold time T2 may be set to 2 seconds.

[0060] The storage device 11 can store a target pressure value of hydrogen gas during the startup of the fuel cell system. Here, for example, the target pressure value of hydrogen gas can be set to 130 kPa.

[0061] The storage device 11 may store a third threshold value P3 (e.g., 10 kPa) for the difference between the target pressure value of hydrogen gas and the current pressure value (the pressure value measured by the first pressure sensor 130 or the second pressure sensor 131). If the third threshold value P3 is set to a value that is too small, the number of startup failures may increase. If the third threshold value P3 is set to a value that is too large, the fuel cell system may be started while the pressure of the hydrogen gas supplied to the FCS 140 is low. This generates a reverse voltage, which accelerates the degradation of the FCS 140.

[0062] The storage device 11 may store a third threshold time T3 for the time when the difference between the target pressure value of hydrogen and the current pressure value (the pressure value measured by the first pressure sensor 130 or the second pressure sensor 131) exceeds the third threshold value P3. Here, for example, the third threshold time T3 may be set to 500 ms.

[0063] Furthermore, when the fuel cell system is in operation, the storage device 11 may store a fourth threshold value P4 (e.g., 100 kPa) for the pressure value measured by the first pressure sensor 130 and the pressure value measured by the second pressure sensor 131. Here, when the fuel cell system is in operation, the fourth threshold value P4 is a value used to determine whether to perform fault diagnosis.

[0064] The storage device 11 may store a fifth threshold value P5 (e.g., 4 kPa) for a moving average value of a difference between a pressure value measured by the first pressure sensor 130 and a pressure value measured by the second pressure sensor 131. Here, when the fifth threshold value P5 is set too large, the operation of the fuel cell system may be continued in a hydrogen-deficient state, and when the fifth threshold value P5 is set too small, excessive hydrogen may be supplied to reduce the fuel ratio.

[0065] The storage device 11 may include at least one type of storage medium among memories of flash memory type, hard disk type, micro type, and card type (e.g., secure digital (SD) card or extreme digital (XD) card), and memories of random access memory (RAM) type, static RAM (SRAM) type, read-only memory (ROM) type, programmable ROM (PROM) type, electrically erasable ROM (EEPROM) type, magnetic RAM (MRAM) type, magnetic disk type, and optical disk type.

[0066] The display 12 may be implemented using a cluster, a head-up display (HUD), or an audio-visual navigation (AVN) system, and may provide a user with the results of diagnosing a fault in the fuel cell system.

[0067] The controller 13 performs overall control so that the components can perform their functions normally. The controller 13 can be implemented in the form of hardware or software, or can be implemented in the form of a combination of hardware and software. Preferably, the controller 13 can be implemented using, but not limited to, a microprocessor.

[0068] The controller 13 may perform various controls required in diagnosing whether hydrogen is smoothly supplied into the FCS 140 by using the plurality of pressure sensors 130 and 131 and determining whether to shut down the fuel cell system based on the diagnosis result.

[0069] The controller 13 may perform a timer function.

[0070] In the following, reference will be made to Figures 3 to 5 The operation of the controller 13 is described in detail.

[0071] Figure 3 is a first flow chart illustrating a method for diagnosing a fault in a fuel cell system according to one embodiment of the present disclosure.

[0072] First, in steps 301 and 302, when hydrogen is supplied to the FCS 140, the controller 13 detects a minimum value Pm between a first pressure value measured by the first pressure sensor 130 and a second pressure value measured by the second pressure sensor 131. At this time, the first pressure sensor 130 and the second pressure sensor 131 may periodically measure the pressure of the hydrogen supplied to the FCS 140.

[0073] Next, in 303 , the controller 13 determines whether the detected minimum value Pm is smaller than a first threshold value P1 .

[0074] When the determination result 303 shows that the detected minimum value Pm is not less than the first threshold value P1 , the controller 13 determines that the state of the first pressure sensor 130 and the state of the second pressure sensor 131 are normal, and proceeds to “ 302 ”.

[0075] When the determination result 303 shows that the detected minimum value Pm is smaller than the first threshold value P1 , the controller 13 calculates the absolute value Pa of the difference between the first pressure value and the second pressure value in 304 .

[0076] Next, in 305 , the controller 13 determines whether the calculated absolute value Pa exceeds a second threshold value P2 .

[0077] When the determination result 305 shows that the calculated absolute value Pa does not exceed the second threshold value P2 , the controller 13 determines that the state of the first pressure sensor 130 and the state of the second pressure sensor 131 are normal, and proceeds to “ 302 ”.

[0078] When the determination result 305 shows that the calculated absolute value Pa exceeds the second threshold value P2, the controller 13 determines that the fuel cell system has a fault (abnormality in the supply of hydrogen gas), and stops the supply of hydrogen gas in 306. When the detected minimum value Pm is less than the first threshold value P1 and the calculated absolute value Pa exceeds the second threshold value P2 for more than the first threshold time T1, the controller 13 may determine that the fuel cell system has a fault and may stop the supply of hydrogen gas.

[0079] Figure 4 is a second flow chart illustrating a method for diagnosing a fault in a fuel cell system according to one embodiment of the present disclosure.

[0080] First, when the fuel cell system is started in 401, the controller 13 determines in 402 Figure 1 When the fuel cell system is started, the controller 13 may determine whether hydrogen is normally supplied to the FCS 140 through the controller of the hydrogen supply system.

[0081] When the determination result 402 shows that there is an abnormality in the hydrogen supply system, the controller 13 stops the start-up of the fuel cell system in 403 .

[0082] When the determination result 402 indicates that there is no abnormality in the hydrogen supply system, the controller 13 determines whether the difference between the target pressure value (constant value) at startup and the current pressure value is less than a third threshold value P3 in 404. Here, the current pressure value as the sensor pressure value may be any one of the first pressure value measured by the first pressure sensor 130, the second pressure value measured by the second pressure sensor 131, the maximum value of the first pressure value and the second pressure value, and the average value of the first pressure value and the second pressure value.

[0083] When the determination result 404 shows that the difference between the target pressure value (constant value) at the time of startup and the current pressure value is not less than the third threshold value P3, the controller 13 stops the startup of the fuel cell system in 403.

[0084] When the determination result 404 shows that the difference between the target pressure value (constant value) at startup and the current pressure value is less than the third threshold value P3, the controller 13 completes the startup of the fuel cell system in 405. When there is no abnormality in the hydrogen supply system within the second threshold time and the difference between the target pressure value (constant value) at startup and the current pressure value is less than the third threshold value P3 for the third threshold time T3, the controller 13 may complete the startup of the fuel cell system.

[0085] When the diagnosis process in the first flowchart is executed, the diagnosis process in the second flowchart may be additionally executed.

[0086] Figure 5 is a third flow chart illustrating a method for diagnosing a fault in a fuel cell system according to one embodiment of the present disclosure.

[0087] First, in 501 , the controller 13 calculates a target pressure value TP1 corresponding to an output power requirement during operation of the fuel cell system.

[0088] Next, in 502, the controller 13 determines whether the current pressure value exceeds the fourth threshold P4. Here, the current pressure value as the sensor pressure value can be any one of the first pressure value measured by the first pressure sensor 130, the second pressure value measured by the second pressure sensor 131, the maximum value of the first pressure value and the second pressure value, and the average value of the first pressure value and the second pressure value.

[0089] When the determination result in 502 shows that the current pressure value does not exceed the fourth threshold P4, the controller 13 diagnoses that the fuel cell system has no fault, and in 503, sets the calculated target pressure value TP1 as the final target pressure value TP.

[0090] When the determination result in 502 shows that the current pressure value exceeds the fourth threshold P4, in 504, the controller 13 calculates a moving average value E1 of the difference between the first pressure value measured by the first pressure sensor 130 and the second pressure value measured by the second pressure sensor 131.

[0091] Then, in 505, the controller 13 determines whether the calculated moving average value E1 exceeds the fifth threshold P5.

[0092] When the determination result in 505 shows that the calculated moving average value E1 does not exceed the threshold P5, the controller 13 diagnoses that the fuel cell system has no fault, and in 503, sets the calculated target pressure value TP1 as the final target pressure value TP.

[0093] When the determination result shows that the calculated moving average value E1 exceeds the fifth threshold P5, in 506, the controller 13 calculates the final target pressure value TP based on the following equation 1.

[0094] Equation 1:

[0095] TP = TP1+(A×E1)

[0096] Here, TP1 represents the target pressure value corresponding to the output power requirement, and E1 represents the moving average value of the difference between the first pressure value measured by the first pressure sensor 130 and the second pressure value measured by the second pressure sensor 131. At this time, A is a constant value (weight value) that satisfies the relationship 0 < A < 1 and can be, for example, 0.5.

[0097] Meanwhile, in the state where the operation of the fuel cell system is stopped, when there is a history record that the moving average value E1 exceeds the fifth threshold P5, the controller 13 can correct the measurement errors of the first pressure sensor 130 and the second pressure sensor 131.

[0098] The diagnosis process in the third flowchart may be additionally performed while the diagnosis process in the first flowchart is performed, or may be performed after the diagnosis process in the second flowchart is performed.

[0099] Figure 6 is a block diagram illustrating a computing system for executing a fault diagnosis method for a fuel cell system according to one embodiment of the present disclosure.

[0100] refer to Figure 6 The fault diagnosis method for a fuel cell system according to one embodiment of the present disclosure can be implemented by a computing system 1000. The computing system 1000 may include at least one processor 1100, a memory 1300, a user interface input device 1400, a user interface output device 1500, a storage device 1600, and a network interface 1700, which are connected to each other via a bus 1200.

[0101] The processor 1100 may be a central processing unit (CPU) or a semiconductor device that processes instructions stored in the memory 1300 and / or the storage device 1600. The memory 1300 and the storage device 1600 may include various types of volatile or non-volatile storage media. For example, the memory 1300 may include a ROM (Read Only Memory) 1310 and a RAM (Random Access Memory) 1320.

[0102] Therefore, the operation of the method or algorithm described in conjunction with the embodiments disclosed herein can be directly embodied in a hardware or software module executed by the processor 1100 or in a combination thereof. The software module can be stored in a storage medium (i.e., memory 1300 and / or storage device 1600), such as RAM, flash memory, ROM, EPROM, EEPROM, registers, hard disk, removable disk or CD-ROM. An exemplary storage medium can be coupled to the processor 1100, and the processor 1100 can read the information in the storage medium and can record the information in the storage medium. Alternatively, the storage medium can be integrated with the processor 1100. The processor 1100 and the storage medium can be present in an application specific integrated circuit (ASIC). The ASIC can be present in a user terminal. In another case, the processor 1100 and the storage medium can be present in the user terminal as separate components.

[0103] According to an embodiment of the present disclosure, an apparatus and method for diagnosing faults in a fuel cell system diagnoses whether hydrogen is smoothly supplied to a fuel cell stack by using multiple hydrogen pressure sensors and determines whether to shut down the fuel cell system based on the diagnosis results, thereby preventing degradation of the fuel cell stack due to abnormal supply of hydrogen.

[0104] Although the present disclosure has been described above with reference to exemplary embodiments and the accompanying drawings, the present disclosure is not limited thereto, and various modifications and substitutions may be made by those skilled in the art without departing from the spirit and scope of the present disclosure as claimed in the appended claims.

[0105] Therefore, the exemplary embodiments of the present disclosure are provided to illustrate the spirit and scope of the present disclosure, but are not limited thereto, so that the spirit and scope of the present disclosure are not limited by the embodiments. The scope of the present disclosure should be interpreted based on the appended claims, and all technical concepts equivalent to those within the scope of the claims should be included within the scope of the present disclosure.

Claims

1. A device for diagnosing a fault in a fuel cell system, the device comprising: a first pressure sensor configured to measure the pressure of hydrogen gas supplied to the fuel cell stack; a second pressure sensor configured to measure the pressure of hydrogen gas supplied to the fuel cell stack; as well as a controller configured to first diagnose a supply state of hydrogen gas based on a first pressure value measured by the first pressure sensor and a second pressure value measured by the second pressure sensor, and further diagnose the supply state of hydrogen gas based on an absolute value of a difference between the first pressure value and the second pressure value, The controller is further configured to: during startup of the fuel cell system, when the hydrogen supply system is operating normally, start the fuel cell system when the target pressure value at startup minus the current pressure value is less than a third threshold; and when it is determined that the current pressure value during operation of the fuel cell system exceeds the current pressure threshold, calculate a moving average of the difference between the first pressure value and the second pressure value, and diagnose the supply status of hydrogen based on the moving average. When the minimum value between the first pressure value and the second pressure value is greater than or equal to a first threshold value, the controller first diagnoses the supply state of hydrogen as normal.

2. The device according to claim 1, wherein When the minimum value is smaller than the first threshold value and the absolute value exceeds a second threshold value, the controller further diagnoses the supply state of hydrogen gas as abnormal.

3. The device according to claim 1, wherein The controller further diagnoses the supply state of hydrogen as abnormal when the minimum value is smaller than the first threshold value and the state in which the absolute value exceeds a second threshold value continues for more than a first threshold time.

4. The apparatus according to claim 1, wherein The current pressure value is any one of the following values: the first pressure value, the second pressure value, a maximum value of the first pressure value and the second pressure value, and an average value of the first pressure value and the second pressure value.

5. The apparatus according to claim 1, wherein During startup of the fuel cell system, the controller starts the fuel cell system when there is no abnormality in the hydrogen supply system within a second threshold time and when the target pressure value minus the current pressure value is less than the third threshold value for a third threshold time.

6. The device according to claim 5, wherein The current pressure value is any one of the following values: the first pressure value, the second pressure value, a maximum value of the first pressure value and the second pressure value, and an average value of the first pressure value and the second pressure value.

7. The apparatus according to claim 1, wherein When the supply state of hydrogen is diagnosed as abnormal, the controller calculates the final target pressure value based on TP=TP1+(A×E1). Here, TP1 represents a target pressure value corresponding to the output power requirement, E1 represents the moving average value, and A represents a weight value.

8. A method for diagnosing a fault in a fuel cell system, the method comprising the steps of: measuring the pressure of hydrogen gas supplied to the fuel cell stack by a first pressure sensor; measuring the pressure of hydrogen gas supplied to the fuel cell stack by a second pressure sensor; first diagnosing, by a controller, a supply state of hydrogen gas based on a first pressure value measured by the first pressure sensor and a second pressure value measured by the second pressure sensor; and further diagnosing, by the controller, a supply status of the hydrogen gas based on an absolute value of a difference between the first pressure value and the second pressure value, The controller is further configured to: during startup of the fuel cell system, when the hydrogen supply system is operating normally, start the fuel cell system when the target pressure value at startup minus the current pressure value is less than a third threshold; and when it is determined that the current pressure value during operation of the fuel cell system exceeds the current pressure threshold, calculate a moving average of the difference between the first pressure value and the second pressure value, and diagnose the supply status of hydrogen based on the moving average. Among them, the first diagnosis of hydrogen supply status includes: When the minimum value of the first pressure value and the second pressure value is greater than or equal to a first threshold value, the supply state of hydrogen gas is initially diagnosed as normal.

9. The method according to claim 8, wherein Further diagnosis of the hydrogen supply status includes: When the minimum value is smaller than the first threshold value and the absolute value exceeds a second threshold value, the supply state of hydrogen gas is diagnosed as abnormal.

10. The method according to claim 8, wherein Further diagnosis of the hydrogen supply status includes: When the minimum value is smaller than the first threshold value and the state in which the absolute value exceeds the second threshold value continues for more than a first threshold time, the supply state of hydrogen gas is diagnosed as abnormal.

11. The method according to claim 8, wherein The current pressure value is any one of the following values: the first pressure value, the second pressure value, a maximum value of the first pressure value and the second pressure value, and an average value of the first pressure value and the second pressure value.

12. The method according to claim 8, further comprising: During startup of the fuel cell system, when there is no abnormality in the hydrogen supply system within a second threshold time and the target pressure minus the current pressure value is less than the third threshold value for a third threshold time, the fuel cell system is started.

13. The method according to claim 12, wherein: The current pressure value is any one of the following values: the first pressure value, the second pressure value, a maximum value of the first pressure value and the second pressure value, and an average value of the first pressure value and the second pressure value.

14. The method according to claim 8, wherein Diagnosing the supply status of hydrogen based on the moving average includes: When the supply state of hydrogen gas is diagnosed as abnormal, the final target pressure value is calculated based on TP=TP1+(A×E1). Here, TP1 represents a target pressure value corresponding to the output power requirement, E1 represents the moving average value, and A represents a weight value.

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