A method and system for determining and controlling hydrogen leakage faults in fuel cell vehicles.

Abstract

This invention discloses a method and system for determining and controlling hydrogen leakage faults in fuel cell vehicles. The method includes determining the vehicle's operating state, which includes normal driving, high-voltage idling, and low-voltage idling. It also involves real-time monitoring of the hydrogen concentration in the vehicle's fuel cell system. When the hydrogen concentration exceeds a preset concentration threshold: if the vehicle is in normal driving, a hydrogen leakage fault handling mechanism is executed; if the vehicle is in high-voltage idling, the hydrogen storage system pressure is checked, and the decision to execute the hydrogen leakage fault handling mechanism is determined based on the result; if the vehicle is in low-voltage idling, the power supply voltage of the hydrogen concentration sensor and the hydrogen storage system pressure are checked, and the decision to execute the hydrogen leakage fault handling mechanism is determined based on the result. This method effectively distinguishes between actual leaks and sensor malfunctions or residual hydrogen interference from exhaust emissions, significantly reducing false alarm rates and improving the accuracy and reliability of hydrogen safety management.

Description

Technical Field

[0001] This application relates to the field of hydrogen system safety control, specifically to a method and system for determining and controlling hydrogen leakage faults in fuel cell vehicles. Background Technology

[0002] Hydrogen fuel cell vehicles are an important development direction for the automotive industry, and monitoring hydrogen leakage in their hydrogen storage systems and supply paths has always been a key focus of vehicle safety control.

[0003] To monitor hydrogen leakage in a vehicle, hydrogen concentration sensors are typically placed in key areas of the vehicle to read their signals in real time. When the detected hydrogen concentration exceeds a preset safety threshold, a hydrogen leakage fault is identified, triggering an alarm or implementing safety measures such as valve shut-off and shutdown.

[0004] However, in practical applications, existing hydrogen leak monitoring and fault diagnosis strategies still have many shortcomings, which can easily lead to false alarms or missed alarms, affecting vehicle safety and user experience. When the sensor's own signal is abnormal, it is easy to misjudge it as a hydrogen leak causing the vehicle to shut down unexpectedly; when the fuel cell is shut down for purging, residual hydrogen in the exhaust can easily drift to the sensor, which can easily trigger false alarms. Furthermore, the existing warning mechanism lacks differentiated strategies for different operating scenarios, and a single logic cannot take into account both safety and accuracy under different operating conditions, which can easily lead to false alarms or missed alarms.

[0005] Therefore, how to reduce the false alarm rate and ensure safety under actual leakage conditions is a technical problem that urgently needs to be solved in the field of hydrogen fuel cell vehicle control technology. Summary of the Invention

[0006] This application provides a method and system for determining and controlling hydrogen leakage faults in fuel cell vehicles, which can solve the technical problem in the prior art that the determination of hydrogen leakage faults is inaccurate due to the failure to consider hydrogen concentration sensor failures and interference from residual hydrogen in fuel cell exhaust.

[0007] In a first aspect, embodiments of this application provide a method for determining and controlling hydrogen leakage faults in fuel cell vehicles, the method comprising: Determine the vehicle's operating status, including normal driving status, high-voltage idling status, and low-voltage idling status; The hydrogen concentration of the vehicle's fuel cell system is monitored in real time, and when the hydrogen concentration exceeds a preset concentration threshold: If the vehicle is in normal driving condition, the hydrogen leak fault handling mechanism will be executed; If the vehicle is in an idling high voltage state, the hydrogen storage system pressure is checked, and the hydrogen leakage fault handling mechanism is determined based on the pressure check result. If the vehicle is in an idling low voltage state, the power supply voltage of the hydrogen concentration sensor and the pressure of the hydrogen storage system are checked. Based on the power supply voltage and pressure check results, it is determined whether to implement the hydrogen leakage fault handling mechanism.

[0008] Secondly, embodiments of this application provide a hydrogen leakage fault determination and control system for fuel cell vehicles, the system comprising: A status determination module is used to determine the operating status of the vehicle, wherein the operating status includes normal driving status, high voltage idling status, and low voltage idling status. A concentration detection module is used to detect the hydrogen concentration in the vehicle's fuel cell system in real time. A fault handling module is used to handle situations where the hydrogen concentration exceeds a preset concentration threshold: If the vehicle is in normal driving condition, the hydrogen leak fault handling mechanism will be executed; If the vehicle is in an idling high voltage state, the hydrogen storage system pressure is checked, and the hydrogen leakage fault handling mechanism is determined based on the pressure check result. If the vehicle is in an idling low voltage state, the power supply voltage of the hydrogen concentration sensor and the pressure of the hydrogen storage system are checked. Based on the power supply voltage and pressure check results, it is determined whether to implement the hydrogen leakage fault handling mechanism.

[0009] The hydrogen leakage fault determination and control system for fuel cell vehicles provided in this application embodiment determines the vehicle's operating state, including normal driving, high-voltage idling, and low-voltage idling; it monitors the hydrogen concentration of the vehicle's fuel cell system in real time. When the hydrogen concentration exceeds a preset concentration threshold: if the vehicle is in normal driving, a hydrogen leakage fault handling mechanism is executed; if the vehicle is in high-voltage idling, the hydrogen storage system pressure is checked, and the decision to execute the hydrogen leakage fault handling mechanism is determined based on the pressure check result; if the vehicle is in low-voltage idling, the power supply voltage of the hydrogen concentration sensor and the hydrogen storage system pressure are checked, and the decision to execute the hydrogen leakage fault handling mechanism is determined based on the power supply voltage and pressure check results. This solves the technical problems in related technologies where the hydrogen leakage fault determination strategy is singular and easily affected by abnormal power supply to the hydrogen concentration sensor and interference from residual hydrogen in the fuel cell system exhaust, leading to false alarms.

[0010] This application develops differentiated judgment strategies for different operating scenarios and introduces hydrogen storage system pressure and sensor power supply voltage as cross-validation conditions. This effectively distinguishes between real hydrogen leaks, sensor malfunctions, and residual hydrogen interference during fuel cell purging, thereby significantly reducing false alarm rates, preventing unexpected vehicle downtime, and ensuring timely response when a real leak is confirmed, thus improving the accuracy and reliability of vehicle hydrogen safety management. Attached Figure Description

[0011] Figure 1 This is a schematic diagram of the hydrogen storage system structure of this application; Figure 2 This is a flowchart illustrating an embodiment of the hydrogen leakage fault determination and control method for fuel cell vehicles according to this application. Figure 3 This is a schematic diagram of the architecture of an embodiment of the hydrogen leakage fault determination and control system for fuel cell vehicles according to this application. Detailed Implementation

[0012] To enable those skilled in the art to better understand the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present application, and not all embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present application.

[0013] First, some of the technical terms used in this application will be explained to help those skilled in the art understand this application.

[0014] HMS: Onboard hydrogen system controller; FCCU: Gas-fired power system controller; VCU: Vehicle Control Unit; Ready: The entire vehicle is under high voltage. Shutdown purging: After the fuel cell stops working, a large amount of air is injected into the stack using an air compressor, and the residual moisture inside the stack is carried away by the air flow.

[0015] To make the objectives, technical solutions, and advantages of this application clearer, the embodiments of this application will be described in further detail below with reference to the accompanying drawings.

[0016] like Figure 1 As shown, the hydrogen storage system on a fuel cell vehicle typically includes components such as a hydrogen refueling port, hydrogen storage cylinders (or groups), cylinder valves, high-pressure sensors, pressure reducing valves, and medium-pressure sensors. The hydrogen storage system is connected to the fuel cell engine to supply the hydrogen required for the reaction. To achieve vehicle-wide hydrogen safety monitoring, hydrogen concentration sensors are deployed around key areas of the vehicle (including but not limited to the hydrogen storage cylinder port and fuel cell system). These hydrogen concentration sensors are communicatively connected to the onboard hydrogen system controller (HMS) to collect and transmit ambient hydrogen concentration data in real time.

[0017] In actual operation, the hydrogen leakage fault signal received by the vehicle hydrogen system controller (HMS) mainly originates from the following three situations: The first scenario involves a sealing failure in a hydrogen storage system component (such as valves, pipes, and connectors), causing hydrogen to leak and spread into the detection range of the hydrogen concentration sensor. When the detected hydrogen concentration reaches a preset fault alarm threshold, a leak fault signal is triggered. This scenario represents a real leak fault.

[0018] Secondly, the operating status of the hydrogen concentration sensor is greatly affected by the power supply voltage and its health status. When the sensor's power supply voltage is lower than the normal operating range, or when the sensor itself drifts or malfunctions, it may output an abnormally high concentration signal, causing the system to generate a false alarm for hydrogen leakage.

[0019] Thirdly, during the operation of the fuel cell system, especially during the shutdown purging phase, residual hydrogen in the stack and pipelines will be discharged through the exhaust. If the hydrogen concentration sensor is located close to the exhaust outlet, the residual hydrogen discharged during the purging process may diffuse to the sensor, causing a sudden increase in local concentration, thus triggering a false alarm for hydrogen leakage.

[0020] In a first aspect, embodiments of this application provide a method for determining and controlling hydrogen leakage faults in fuel cell vehicles to solve the aforementioned technical problems.

[0021] In one embodiment, reference is made to Figure 2 , Figure 2 This is a flowchart illustrating the first embodiment of the hydrogen leakage fault determination and control method for fuel cell vehicles according to this application. Figure 2 As shown, the methods for determining and controlling hydrogen leakage faults in fuel cell vehicles include: The vehicle's operating status is determined, including normal driving, high-voltage idling, and low-voltage idling; the hydrogen concentration of the vehicle's fuel cell system is monitored in real time; when the hydrogen concentration exceeds a preset concentration threshold, the following operations are performed according to the different vehicle operating states: If the vehicle is in normal driving condition, the hydrogen leak fault handling mechanism will be executed; If the vehicle is in an idling high voltage state, the hydrogen storage system pressure is checked, and the hydrogen leakage fault handling mechanism is determined based on the pressure check result. If the vehicle is in an idling low voltage state, the power supply voltage of the hydrogen concentration sensor and the pressure of the hydrogen storage system are checked. Based on the power supply voltage and pressure check results, it is determined whether to implement the hydrogen leakage fault handling mechanism.

[0022] It is worth noting that the embodiments of this application combine vehicle operating status, hydrogen storage system pressure and sensor power supply voltage for multi-dimensional verification to solve the technical problem of false alarm of hydrogen leakage fault caused by sensor abnormality, residual hydrogen interference in the tail exhaust and single operating condition strategy in the prior art, thereby improving the accuracy and reliability of vehicle hydrogen safety management.

[0023] To facilitate understanding, the hydrogen leakage fault handling mechanism in this application will first be explained. The hydrogen leakage fault handling mechanism in this embodiment adopts a hierarchical response strategy. Based on the different detected hydrogen concentrations, the leakage fault is divided into a first-level leakage fault and a second-level leakage fault, and the corresponding control logic is executed.

[0024] Specifically, the identification and handling of Level 1 leakage faults includes: When the hydrogen concentration is greater than a preset first concentration threshold and less than or equal to a preset second concentration threshold, and the duration is greater than a preset first duration, the vehicle control unit (VCU) determines that a level-one leakage fault exists. For a level-one leakage fault, differentiated operations are performed based on the current operating state of the fuel cell system: If the fuel cell system is operational: the vehicle controller (VCU) sends a shutdown command to the fuel cell system controller (FCCU) to stop the fuel cell stack reaction. Simultaneously, the onboard hydrogen system controller (HMS) starts a safety timer. If the HMS does not receive a valve-closing command from the VUC within a second preset time (e.g., 300 seconds) (possibly due to communication failure or VCU malfunction), the HMS will independently execute the valve-closing operation, closing the hydrogen storage tank valve. This redundant design ensures timely disconnection of the hydrogen source even in the event of controller communication failure.

[0025] If the fuel cell system is not in operation: the vehicle controller (VCU) controls the fuel cell system controller (FCCU) to be in a prohibited start state to prevent accidental system start-up from exacerbating the risk of leakage. Simultaneously, the VCU continuously sends valve-closing commands to the on-board hydrogen system controller (HMS), and the HMS responds by closing the hydrogen storage tank valve.

[0026] Level 2 leakage fault identification and handling include: When the hydrogen concentration exceeds the second concentration threshold and the duration exceeds the first preset duration, the vehicle control unit (VCU) determines that a secondary leakage fault exists, indicating an extremely high leakage risk. At this time, the on-board hydrogen system controller closes the hydrogen storage cylinder valve, and the VCU immediately sends an emergency valve-closing command to the on-board hydrogen system controller (HMS).

[0027] For example, the first concentration threshold and the second concentration threshold can be selected between 10,000 and 30,000 ppm, with the second concentration threshold being greater than the first concentration threshold. The first preset duration can be set to any value between 3 and 10 seconds, specifically calibrated according to the controller communication cycle and valve response time. For instance, the first concentration threshold can be set to 10,000 ppm, the second concentration threshold can be set to 30,000 ppm, and the first preset duration can be set to 3 seconds.

[0028] This embodiment achieves precise responses to leakage faults of varying severity through the aforementioned graded processing mechanism. Simultaneously, the introduction of an independent timed valve-closing mechanism via HMS effectively prevents valve-closing failures due to VCU communication malfunctions, thereby enhancing the system's safety redundancy.

[0029] Preferably, if the possibility of a genuine leak in the hydrogen storage system is ruled out, and it is determined that the hydrogen concentration exceeding the concentration threshold is due to a false alarm caused by a sensor malfunction, the control system will only issue a sensor fault warning signal and will not execute the valve closure operation at the hydrogen storage cylinder. This measure aims to avoid unexpected vehicle shutdowns caused by sensor false alarms, thereby improving the user experience while ensuring safety.

[0030] In an optional embodiment, the system also provides a fault clearance mechanism. When a primary leakage fault exists, if the hydrogen concentration is less than a first concentration threshold, the fault is determined to be cleared; when a secondary leakage fault exists, if the vehicle is powered on and off again and its self-test is normal, the fault is determined to be cleared. This mechanism allows the vehicle's normal operating privileges to be restored after the fault conditions are resolved.

[0031] The following section elaborates on the specific process of the hydrogen leakage fault determination and control method for fuel cell vehicles provided in this application embodiment, taking into account the specific operating conditions of the vehicle.

[0032] In one embodiment, the vehicle control unit (VCU) is configured to monitor the vehicle's driving status in real time to determine the vehicle's current operating condition. Specifically, when the VCU determines that the vehicle's speed is greater than zero, it determines that the vehicle is in a normal driving state.

[0033] Under normal driving conditions, based on the principle of safety first, regardless of whether the fuel cell system is in operation or not, once the on-board hydrogen system controller (HMS) detects that the hydrogen concentration value reaches or exceeds a preset first concentration threshold, the hydrogen leakage fault handling mechanism described in the aforementioned embodiments is triggered. The specific execution steps and logic of the hydrogen leakage fault handling mechanism have been described in detail in the aforementioned embodiments and will not be repeated here.

[0034] Preferably, to further ensure vehicle safety, the vehicle controller also simultaneously controls the vehicle to cut off the high-voltage electrical circuit to prevent the high-voltage arc from igniting the leaked hydrogen, thereby avoiding hydrogen-electric safety accidents.

[0035] In one embodiment, when the vehicle is detected to be in a Ready state and its speed is zero, it is determined that the vehicle is in an idling high-voltage state. In the idling high-voltage state, in response to the hydrogen concentration exceeding a first concentration threshold, the hydrogen storage system pressure is checked, and different judgments and controls are performed depending on whether the fuel cell system is in a purging state. Specifically, this includes the following two scenarios: When the fuel cell system is in purging mode: If the on-board hydrogen system controller (HMS) detects that the hydrogen concentration exceeds the first concentration threshold and the fuel cell system is in the shutdown purging phase, the pressure status of the hydrogen storage system is first checked. In this embodiment, the specific methods for pressure checking include, but are not limited to, monitoring whether the rate of pressure drop or the absolute pressure value after the hydrogen storage cylinder valve exceeds the preset normal purging pressure range.

[0036] If the pressure verification result is abnormal, it indicates that there may be a physical leak in the hydrogen storage system. In this case, the gas-fired power system should immediately stop the purging operation to prevent the leak from worsening and directly implement the hydrogen leak fault handling mechanism.

[0037] If the pressure verification result is normal, it indicates that the increased hydrogen concentration is likely due to the diffusion of residual hydrogen in the exhaust during the purging process, rather than a system leak. In this case, the system continues the purging process to ensure that residual hydrogen in the fuel cell stack and pipelines is fully removed, avoiding impact on the next start-up performance. After the purging process is completed, the vehicle control unit (VCU) or the on-board hydrogen system controller (HMS) sends a valve closing command to the hydrogen storage tank valve. After the hydrogen storage tank valve is closed, the pressure changes in the hydrogen storage system continue to be monitored.

[0038] If the pressure of the hydrogen storage system remains stable within a third preset time period (e.g., the duration of stable pressure reaches the third preset time, which is calibrable, such as 10 seconds), it indicates that the hydrogen storage system has good sealing performance and there is no physical leakage. A persistently high hydrogen concentration sensor reading indicates a hydrogen concentration sensor malfunction. In this case, the system does not execute the hydrogen leakage fault handling mechanism but only issues a sensor fault warning, prompting the user to perform maintenance, thereby avoiding unexpected vehicle downtime due to false sensor alarms.

[0039] If the pressure in the hydrogen storage system cannot remain stable within a preset time, for example, if the pressure drop exceeds the allowable threshold after the valve is closed, this indicates a leak point downstream of the valve or within the valve itself. This is considered a genuine leak, and the hydrogen leak fault handling mechanism will be activated.

[0040] When the fuel cell system is not in a purging state and the on-board hydrogen system controller (HMS) detects that the hydrogen concentration value has reached the preset concentration threshold, the system eliminates the interference factors of residual hydrogen in the exhaust and directly executes the hydrogen leakage fault handling mechanism described in the aforementioned embodiments.

[0041] In one embodiment, when the vehicle control unit (VCU) determines that the vehicle is in a low-pressure idling state (e.g., the vehicle KL15 is powered on but not ready, and the high-pressure system is not connected), if the on-board hydrogen system controller (HMS) detects that the hydrogen concentration value exceeds a first concentration threshold, the system first verifies the power supply voltage of the hydrogen concentration sensor to eliminate false alarms caused by sensor malfunction. The specific determination logic is as follows: If the power supply voltage of the hydrogen concentration sensor is within the preset normal voltage range (e.g., 9~32V), it indicates that the sensor is working well, and its output high concentration signal is highly reliable. In this case, it is determined that there is a high risk of a real hydrogen leak, and the hydrogen leak fault handling mechanism is directly executed to ensure the safety of the entire vehicle.

[0042] If the supply voltage exceeds the normal voltage range (e.g., too low or unstable voltage), it indicates that the sensor may be experiencing signal drift or false alarms due to insufficient power supply. In this case, instead of immediately implementing fault handling, further verify the hydrogen storage system pressure and cross-validate the leak's authenticity using physical pressure data. When the pressure verification result indicates an abnormal pressure, such as an excessively rapid rate of pressure drop in the hydrogen storage system or a pressure drop below a safety threshold, it indicates that even if the sensor power supply is abnormal, there is indeed a physical leak in the hydrogen storage system. In this case, the system still executes the hydrogen leak fault handling mechanism to prevent safety accidents.

[0043] When the pressure verification result is normal, it indicates that the hydrogen storage system is well-sealed and has no physical leakage. Considering the abnormal power supply to the sensor, the system determines that there is a hydrogen concentration sensor malfunction (rather than a hydrogen leak). In this case, the system does not execute the hydrogen leak fault handling mechanism, but only issues a sensor malfunction warning, prompting the user to repair the sensor.

[0044] Preferably, the pressure verification of the hydrogen storage system in this embodiment includes the following steps: acquiring the hydrogen high-pressure pH (collected by a high-pressure sensor) and hydrogen medium-pressure PM (collected by a medium-pressure sensor) of the hydrogen storage system. By simultaneously monitoring the pressure data on the high-pressure side and the medium-pressure side, full coverage monitoring of different sections of the hydrogen storage system can be achieved. If the hydrogen high-pressure drop rate is greater than a preset rate threshold (e.g., pH drop rate > rate threshold a), or the hydrogen medium-pressure exceeds a preset normal pressure range, then the pressure verification result is determined to be abnormal; otherwise, the pressure verification result is determined to be normal.

[0045] This pressure verification method can not only detect static pressure deviations, but also keenly capture dynamic pressure leakage trends, effectively avoiding missed detections caused by errors in a single pressure sensor or slow leakage, and significantly improving the robustness of pressure verification and the accuracy of leakage identification.

[0046] This application employs multi-dimensional cross-validation by combining vehicle operating status, hydrogen storage system pressure, and sensor power supply voltage. It develops differentiated judgment strategies for different operating conditions, effectively distinguishing between actual leaks, sensor malfunctions, and residual hydrogen interference from exhaust emissions, significantly reducing the false alarm rate. Simultaneously, it adopts a graded response mechanism and controller redundancy logic to ensure safety by quickly cutting off the hydrogen source and high-voltage power in the event of a severe leak, while avoiding unexpected vehicle shutdowns caused by general malfunctions. This improves the accuracy, reliability, and user experience of the vehicle's hydrogen safety management.

[0047] Secondly, embodiments of this application also provide a hydrogen leakage fault determination and control system for fuel cell vehicles.

[0048] In one embodiment, reference is made to Figure 3 , Figure 3 This is a functional module diagram of an embodiment of the hydrogen leakage fault determination and control system for fuel cell vehicles according to this application. Figure 3 As shown, the hydrogen leakage fault detection and control system for fuel cell vehicles includes: A status determination module is used to determine the operating status of the vehicle, wherein the operating status includes normal driving status, high voltage idling status, and low voltage idling status. A concentration detection module is used to detect the hydrogen concentration in the vehicle's fuel cell system in real time. A fault handling module is used to handle situations where the hydrogen concentration exceeds a preset concentration threshold: If the vehicle is in normal driving condition, the hydrogen leak fault handling mechanism will be executed; If the vehicle is in an idling high voltage state, the hydrogen storage system pressure is checked, and the hydrogen leakage fault handling mechanism is determined based on the pressure check result. If the vehicle is in an idling low voltage state, the power supply voltage of the hydrogen concentration sensor and the pressure of the hydrogen storage system are checked. Based on the power supply voltage and pressure check results, it is determined whether to implement the hydrogen leakage fault handling mechanism.

[0049] Furthermore, in one embodiment, the fault handling module is also used for: If the fuel cell system is in a purging state, the pressure of the hydrogen storage system is checked, and the hydrogen leakage fault handling mechanism is determined based on the pressure check result. If the fuel cell system is not in a purging state, a hydrogen leakage fault handling mechanism is executed.

[0050] Furthermore, in one embodiment, the fault handling module is also used for: If the pressure verification result is abnormal, purging is stopped and the hydrogen leak fault handling mechanism is executed. If the pressure verification result is normal, the purging process continues, and a valve closing command is sent after the purging is completed. After the hydrogen storage bottle valve is closed, the pressure of the hydrogen storage system is monitored. If the pressure of the hydrogen storage system remains stable within the preset time, it is determined that there is a hydrogen concentration sensor malfunction, and the hydrogen leakage fault handling mechanism is not executed. If the pressure of the hydrogen storage system cannot be maintained stable within a preset time, the hydrogen leakage fault handling mechanism will be executed.

[0051] Furthermore, in one embodiment, the fault handling module is also used for: If the power supply voltage is within the preset normal voltage range, the hydrogen leakage fault handling mechanism will be executed. If the supply voltage exceeds the normal voltage range, then check the hydrogen storage system pressure; When the pressure verification result indicates an abnormal pressure, the hydrogen leakage fault handling mechanism is executed. If the pressure verification result is normal, it is determined that there is a hydrogen concentration sensor malfunction, and the hydrogen leakage fault handling mechanism is not executed.

[0052] Furthermore, in one embodiment, the fault handling module is also used for: When a hydrogen concentration sensor malfunction is detected, a sensor malfunction warning is issued, and the valve closing operation of the hydrogen storage bottle is not performed.

[0053] Furthermore, in one embodiment, the fault handling module is also used for: Obtain the high-pressure and medium-pressure hydrogen of the hydrogen storage system; If the rate of decrease of the hydrogen high pressure is greater than a preset rate threshold, or the hydrogen medium pressure exceeds a preset normal pressure range, then the pressure verification result is determined to be a pressure anomaly. Otherwise, the pressure verification result is determined to be normal.

[0054] Furthermore, in one embodiment, the fault handling module is also used for: When the hydrogen concentration is greater than a preset first concentration threshold and less than or equal to a preset second concentration threshold, a first-level leakage fault is determined, and if the fuel cell system is in operation, a shutdown command is sent to the fuel cell system controller through the vehicle controller. After sending the fault signal, the on-board hydrogen system controller starts a timer. If no valve-closing command is received from the vehicle controller within a preset time, the valve-closing operation is performed independently. If the fuel cell system is not in operation, the fuel cell system is controlled to be in a prohibited start state, and a valve-closing command is sent to the on-board hydrogen system controller through the vehicle controller. When the hydrogen concentration is greater than the second concentration threshold, a secondary leakage fault is determined. Then, the vehicle controller sends a valve closing command to the on-board hydrogen system controller, and the on-board hydrogen system controller closes the hydrogen storage cylinder valve. Furthermore, in one embodiment, the fault handling module is also configured to: when a first-level leakage fault exists, if the hydrogen concentration is less than the first concentration threshold, then determine that the fault has been eliminated; If a secondary leakage fault exists, and the vehicle is powered on and off again and the self-test is normal, then the fault is considered to have been eliminated.

[0055] Furthermore, in one embodiment, the fault handling module is also used for: If the vehicle is in normal driving condition, the hydrogen leak fault handling mechanism is executed, and the high voltage power to the vehicle is cut off through the vehicle controller.

[0056] The functions of each module in the above-mentioned fuel cell vehicle hydrogen leakage fault determination and control system correspond to the steps in the above-mentioned fuel cell vehicle hydrogen leakage fault determination and control method embodiment, and their functions and implementation processes will not be described in detail here.

[0057] It should be noted that the sequence numbers of the embodiments in this application are for descriptive purposes only and do not represent the superiority or inferiority of the embodiments.

[0058] The terms "comprising" and "having," and any variations thereof, in the specification, claims, and accompanying drawings of this application are intended to cover non-exclusive inclusion. For example, a process, method, system, product, or apparatus that includes a series of steps or units is not limited to the listed steps or units, but may optionally include steps or units not listed, or may optionally include other steps or units inherent to such process, method, product, or apparatus. The terms "first," "second," and "third," etc., are used to distinguish different objects, etc., and do not indicate a sequence, nor do they limit "first," "second," and "third" to different types.

[0059] In the description of the embodiments of this application, terms such as "exemplary," "for example," or "for instance" are used to indicate examples, illustrations, or explanations. Any embodiment or design described as "exemplary," "for example," or "for instance" in the embodiments of this application should not be construed as being more preferred or advantageous than other embodiments or designs. Specifically, the use of terms such as "exemplary," "for example," or "for instance" is intended to present the relevant concepts in a concrete manner.

[0060] In the description of the embodiments of this application, unless otherwise stated, " / " means "or". For example, A / B can mean A or B. The "and / or" in the text is merely a description of the relationship between related objects, indicating that there can be three relationships. For example, A and / or B can mean: A exists alone, A and B exist simultaneously, and B exists alone. In addition, in the description of the embodiments of this application, "multiple" means two or more.

[0061] In some processes described in the embodiments of this application, multiple operations or steps are included in a specific order. However, it should be understood that these operations or steps may not be executed in the order they appear in the embodiments of this application, or they may be executed in parallel. The sequence number of the operation is only used to distinguish different operations, and the sequence number itself does not represent any execution order. In addition, these processes may include more or fewer operations, and these operations or steps may be executed sequentially or in parallel, and these operations or steps may be combined.

[0062] Through the above description of the embodiments, those skilled in the art can clearly understand that the methods of the above embodiments can be implemented by means of software plus necessary general-purpose hardware platforms. Of course, they 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 this application, in essence, or the part that contributes to the prior art, can be embodied in the form of a software product. This computer software product is stored in a storage medium (such as ROM / RAM, magnetic disk, optical disk) as described above, and includes several instructions to cause a terminal device to execute the methods described in the various embodiments of this application.

[0063] The above are merely preferred embodiments of this application and do not limit the patent scope of this application. Any equivalent structural or procedural transformations made using the content of this application's specification and drawings, or direct or indirect applications in other related technical fields, are similarly included within the patent protection scope of this application.

Claims

1. A method for determining and controlling hydrogen leakage faults in fuel cell vehicles, characterized in that, The method for determining and controlling hydrogen leakage faults in fuel cell vehicles includes: Determine the vehicle's operating status, including normal driving status, high-voltage idling status, and low-voltage idling status; The hydrogen concentration of the vehicle's fuel cell system is monitored in real time, and when the hydrogen concentration exceeds a preset concentration threshold: If the vehicle is in normal driving condition, the hydrogen leak fault handling mechanism will be executed; If the vehicle is in an idling high voltage state, the hydrogen storage system pressure is checked, and the hydrogen leakage fault handling mechanism is determined based on the pressure check result. If the vehicle is in an idling low voltage state, the power supply voltage of the hydrogen concentration sensor and the pressure of the hydrogen storage system are checked. Based on the power supply voltage and pressure check results, it is determined whether to implement the hydrogen leakage fault handling mechanism.

2. The method for determining and controlling hydrogen leakage faults in fuel cell vehicles as described in claim 1, characterized in that, If the vehicle is in an idling high-voltage state, the hydrogen storage system pressure is checked, and based on the pressure check result, it is determined whether to implement the hydrogen leak fault handling mechanism, including: If the fuel cell system is in a purging state, the pressure of the hydrogen storage system is checked, and the hydrogen leakage fault handling mechanism is determined based on the pressure check result. If the fuel cell system is not in a purging state, a hydrogen leakage fault handling mechanism is executed.

3. The method for determining and controlling hydrogen leakage faults in fuel cell vehicles as described in claim 2, characterized in that, If the fuel cell system is in a purging state, the hydrogen storage system pressure is checked, and based on the pressure check result, it is determined whether to implement the hydrogen leakage fault handling mechanism, including: If the pressure verification result is abnormal, purging is stopped and the hydrogen leak fault handling mechanism is executed. If the pressure verification result is normal, the purging process continues, and a valve closing command is sent after the purging is completed. After the hydrogen storage bottle valve is closed, the pressure of the hydrogen storage system is monitored. If the pressure of the hydrogen storage system remains stable within the preset time, it is determined that there is a hydrogen concentration sensor malfunction, and the hydrogen leakage fault handling mechanism is not executed. If the pressure of the hydrogen storage system cannot be maintained stable within a preset time, the hydrogen leakage fault handling mechanism will be executed.

4. The method for determining and controlling hydrogen leakage faults in fuel cell vehicles as described in claim 1, characterized in that, If the vehicle is in an idling low-voltage state, the power supply voltage of the hydrogen concentration sensor and the pressure of the hydrogen storage system are checked. Based on the power supply voltage and pressure check results, it is determined whether to implement the hydrogen leak fault handling mechanism, including: If the power supply voltage is within the preset normal voltage range, the hydrogen leakage fault handling mechanism will be executed. If the supply voltage exceeds the normal voltage range, then check the hydrogen storage system pressure; When the pressure verification result indicates an abnormal pressure, the hydrogen leakage fault handling mechanism is executed. If the pressure verification result is normal, it is determined that there is a hydrogen concentration sensor malfunction, and the hydrogen leakage fault handling mechanism is not executed.

5. The method for determining and controlling hydrogen leakage faults in fuel cell vehicles as described in any one of claims 3 or 4, characterized in that, When a hydrogen concentration sensor malfunction is confirmed, the following is also included: It issues a sensor malfunction warning but does not perform the valve closing operation on the hydrogen storage cylinder.

6. The method for determining and controlling hydrogen leakage faults in fuel cell vehicles as described in claim 1, characterized in that, Verifying the pressure of the hydrogen storage system includes: Obtain the high-pressure and medium-pressure hydrogen of the hydrogen storage system; If the rate of decrease of the hydrogen high pressure is greater than a preset rate threshold, or the hydrogen medium pressure exceeds a preset normal pressure range, then the pressure verification result is determined to be a pressure anomaly. Otherwise, the pressure verification result is determined to be normal.

7. The method for determining and controlling hydrogen leakage faults in fuel cell vehicles as described in claim 1, characterized in that, The hydrogen leak fault handling mechanism includes: When the hydrogen concentration is greater than a preset first concentration threshold and less than or equal to a preset second concentration threshold, a first-level leakage fault is determined, and if the fuel cell system is in operation, a shutdown command is sent to the fuel cell system controller through the vehicle controller. After sending the fault signal, the on-board hydrogen system controller starts a timer. If no valve-closing command is received from the vehicle controller within a preset time, the valve-closing operation is performed independently. If the fuel cell system is not in operation, the fuel cell system is controlled to be in a prohibited start state, and a valve-closing command is sent to the on-board hydrogen system controller through the vehicle controller. When the hydrogen concentration is greater than the second concentration threshold, a secondary leakage fault is determined. Then, the vehicle controller sends a valve closing command to the on-board hydrogen system controller, and the on-board hydrogen system controller closes the hydrogen storage cylinder valve.

8. The method for determining and controlling hydrogen leakage faults in fuel cell vehicles as described in claim 7, characterized in that, The method also includes a fault elimination mechanism: When a Level 1 leakage fault exists, if the hydrogen concentration is less than the first concentration threshold, the fault is determined to be eliminated. If a secondary leakage fault exists, and the vehicle is powered on and off again and the self-test is normal, then the fault is considered to have been eliminated.

9. The method for determining and controlling hydrogen leakage faults in fuel cell vehicles as described in claim 1, characterized in that, If the vehicle is in normal driving condition, the hydrogen leak fault handling mechanism is implemented, which also includes: The high-voltage power to the vehicle is cut off by the vehicle controller.

10. A hydrogen leakage fault detection and control system for fuel cell vehicles, characterized in that, The fuel cell vehicle hydrogen leakage fault detection and control system includes: A status determination module is used to determine the operating status of the vehicle, wherein the operating status includes normal driving status, high voltage idling status, and low voltage idling status. A concentration detection module, used to detect the hydrogen concentration in the vehicle's fuel cell system in real time; A fault handling module is used when the hydrogen concentration exceeds a preset concentration threshold: If the vehicle is in normal driving condition, the hydrogen leak fault handling mechanism will be executed; If the vehicle is in an idling high voltage state, the hydrogen storage system pressure is checked, and the hydrogen leakage fault handling mechanism is determined based on the pressure check result. If the vehicle is in an idling low voltage state, the power supply voltage of the hydrogen concentration sensor and the pressure of the hydrogen storage system are checked. Based on the power supply voltage and pressure check results, it is determined whether to implement the hydrogen leakage fault handling mechanism.

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