Vehicle insulation fault diagnosis method, device, equipment and storage medium

Abstract

The application discloses a vehicle insulation fault diagnosis method, device and equipment and a storage medium, and belongs to the technical field of hydrogen fuel vehicles. When it is detected that a vehicle is in an upper high-voltage state, a first insulation resistance value after a high-voltage power battery system is started is acquired, and the starting duration of the vehicle is recorded; insulation fault diagnosis is performed on the high-voltage power battery system according to the first insulation resistance value; if the high-voltage power battery system does not have insulation faults, whether the hydrogen fuel cell system is started is detected when the starting duration reaches a preset duration; if the hydrogen fuel cell system is started, a second insulation resistance value after the hydrogen fuel cell system and the high-voltage power battery system are simultaneously started is acquired; insulation fault diagnosis is performed on the hydrogen fuel cell system and the high-voltage power battery system according to the second insulation resistance value, the high-voltage power battery and the hydrogen fuel cell can be integrally diagnosed for insulation faults, and the hydrogen fuel cell can be efficiently and quickly diagnosed for insulation faults in an external mode.

Description

Technical Field

[0001] This invention relates to the field of hydrogen fuel cell vehicle technology, and in particular to a method, apparatus, equipment and storage medium for diagnosing vehicle insulation faults. Background Technology

[0002] Insulation diagnostics for hydrogen fuel cells is a significant challenge. As vehicle operating time and the hydrogen fuel cell's usage time increase, a decline in insulation performance is inevitable. When the insulation resistance falls below a certain threshold, replacement of the deionized water filter or other repairs are necessary to improve the fuel cell's insulation and reduce vehicle malfunctions. Range-extended hydrogen fuel cell vehicles have two power sources: a high-voltage battery system and a hydrogen fuel cell system. Currently, insulation diagnostics for hydrogen fuel cells rely on internal fuel cell parameters and do not address the overall insulation of the hydrogen fuel cell and the high-voltage battery system.

[0003] The above content is only used to help understand the technical solution of the present invention and does not represent an admission that the above content is prior art. Summary of the Invention

[0004] The main objective of this invention is to provide a method, apparatus, device, and storage medium for diagnosing vehicle insulation faults, aiming to solve the technical problem that the prior art does not cover the overall insulation diagnosis of hydrogen fuel cells and high-voltage power batteries.

[0005] To achieve the above objectives, the present invention provides a method for diagnosing insulation faults in a vehicle, the vehicle comprising a hydrogen fuel cell system and a high-voltage power battery system, the method comprising:

[0006] The vehicle insulation fault diagnosis method includes the following steps:

[0007] When the vehicle is detected to be in a high-voltage state, the first insulation resistance value of the high-voltage power battery system after startup is obtained, and the startup time of the vehicle is recorded.

[0008] The high-voltage power battery system is diagnosed for insulation faults based on the first insulation resistance value.

[0009] If the high-voltage power battery system does not have an insulation fault, then when the startup time reaches the preset time, it is detected whether the hydrogen fuel cell system has started.

[0010] If started, the second insulation resistance value is obtained after the hydrogen fuel cell system and the high-voltage power battery system are started simultaneously;

[0011] Insulation fault diagnosis is performed on the hydrogen fuel cell system and the high-voltage power battery system based on the second insulation resistance value.

[0012] Optionally, the insulation fault diagnosis of the hydrogen fuel cell system and the high-voltage power battery system based on the second insulation resistance value includes:

[0013] The second insulation resistance value is compared with the first resistance threshold and the second resistance threshold respectively, wherein the first resistance threshold is less than the second resistance threshold;

[0014] If the second insulation resistance value is greater than or equal to the second resistance threshold, it is determined that neither the hydrogen fuel cell system nor the high-voltage power battery system has an insulation fault.

[0015] If the second insulation resistance value is greater than or equal to the first resistance threshold and less than the second resistance threshold, and the duration exceeds the first preset duration, then it is determined that the hydrogen fuel cell system and / or the high-voltage power battery system have a low-level insulation fault.

[0016] Optionally, the vehicle insulation fault diagnosis method further includes:

[0017] If the second insulation resistance value is less than the first resistance threshold, then the vehicle is powered off.

[0018] After the vehicle is powered off, control the vehicle to restart and enter the high-voltage state;

[0019] Obtain the third insulation resistance value after the vehicle re-enters the high-voltage state;

[0020] Insulation fault diagnosis is performed on the hydrogen fuel cell system and the high-voltage power battery system based on the third insulation resistance value.

[0021] Optionally, the insulation fault diagnosis of the hydrogen fuel cell system and the high-voltage power battery system based on the third insulation resistance value includes:

[0022] If the third insulation resistance value is less than the first resistance threshold, it is determined that the high-voltage power battery system has a high-level insulation fault.

[0023] If the third insulation resistance value is greater than or equal to the first resistance threshold, less than the second resistance threshold, and the duration exceeds the first preset duration, then it is determined that the hydrogen fuel cell system has a high-level insulation fault and the high-voltage power battery system has a low-level insulation fault.

[0024] If the third insulation resistance value is greater than or equal to the second resistance threshold and the duration exceeds the first preset duration, then it is determined that the hydrogen fuel cell system has a high-level insulation fault, and the high-voltage power battery system does not have an insulation fault.

[0025] Optionally, the vehicle insulation fault diagnosis method further includes:

[0026] If the second insulation resistance value is less than the first resistance threshold, a shutdown request is sent to the hydrogen fuel cell system to shut down the hydrogen fuel cell system.

[0027] Obtain the fourth insulation resistance value of the hydrogen fuel cell system after it is shut down;

[0028] Insulation fault diagnosis is performed on the hydrogen fuel cell system and the high-voltage power battery system based on the fourth insulation resistance value.

[0029] Optionally, the insulation fault diagnosis of the hydrogen fuel cell system and the high-voltage power battery system based on the fourth insulation resistance value includes:

[0030] If the fourth insulation resistance value is less than the first resistance threshold, it is determined that the high-voltage power battery system has a high-level insulation fault.

[0031] If the fourth insulation resistance value is greater than or equal to the first resistance threshold, less than the second resistance threshold, and the duration exceeds the second preset duration, then it is determined that the hydrogen fuel cell system has a high-level insulation fault and the high-voltage power battery system has a low-level insulation fault.

[0032] If the fourth insulation resistance value is greater than or equal to the second resistance threshold and the duration exceeds the second preset duration, it is determined that the hydrogen fuel cell system has a high-level insulation fault, the high-voltage power battery system does not have an insulation fault, and the second preset duration is longer than the first preset duration.

[0033] Optionally, the step of performing insulation fault diagnosis on the high-voltage power battery system based on the first insulation resistance value includes:

[0034] If the first insulation resistance value is less than the first resistance threshold, it is determined that the high-voltage power battery system has a high-level insulation fault.

[0035] If the first insulation resistance value is greater than or equal to the first resistance value threshold, less than the second resistance value threshold, and the duration exceeds the first preset duration, then it is determined that the high-voltage power battery system has a low-level insulation fault.

[0036] If the first insulation resistance value is greater than or equal to the second resistance threshold and the duration exceeds the first preset duration, then it is determined that the high-voltage power battery system does not have an insulation fault.

[0037] Furthermore, to achieve the above objectives, the present invention also proposes a vehicle insulation fault diagnosis device, wherein the vehicle includes a hydrogen fuel cell system and a high-voltage power battery system, and the vehicle insulation fault diagnosis device includes:

[0038] The acquisition module is used to acquire the first insulation resistance value of the high-voltage power battery system after startup when the vehicle is detected to be in a high-voltage state, and to record the startup time of the vehicle.

[0039] The diagnostic module is used to diagnose insulation faults in the high-voltage power battery system based on the first insulation resistance value.

[0040] The detection module is used to detect whether the hydrogen fuel cell system has started when the startup time reaches a preset time if there is no insulation fault in the high-voltage power battery system.

[0041] The acquisition module is also used to acquire the second insulation resistance value after the hydrogen fuel cell system and the high-voltage power battery system are started simultaneously if the system is started.

[0042] The diagnostic module is also used to perform insulation fault diagnosis on the hydrogen fuel cell system and the high-voltage power battery system based on the second insulation resistance value.

[0043] Furthermore, to achieve the above objectives, the present invention also proposes a vehicle insulation fault diagnosis device, the vehicle insulation fault diagnosis device comprising: a memory, a processor, and a vehicle insulation fault diagnosis program stored in the memory and running on the processor, the vehicle insulation fault diagnosis program being configured to implement the vehicle insulation fault diagnosis method as described above.

[0044] In addition, to achieve the above objectives, the present invention also proposes a storage medium storing a vehicle insulation fault diagnosis program, which, when executed by a processor, implements the vehicle insulation fault diagnosis method as described above.

[0045] This invention obtains the first insulation resistance value of the high-voltage power battery system after startup when the vehicle is detected to be in a high-voltage state, and records the startup duration of the vehicle; performs insulation fault diagnosis on the high-voltage power battery system based on the first insulation resistance value; if the high-voltage power battery system does not have an insulation fault, then when the startup duration reaches a preset duration, it detects whether the hydrogen fuel cell system has started; if it has started, it obtains the second insulation resistance value after the hydrogen fuel cell system and the high-voltage power battery system start simultaneously; and performs insulation fault diagnosis on the hydrogen fuel cell system and the high-voltage power battery system based on the second insulation resistance value. This method enables comprehensive insulation fault diagnosis of both the high-voltage power battery and the hydrogen fuel cell, without needing to diagnose the internal state of the hydrogen fuel cell, allowing for efficient and rapid insulation fault diagnosis of the hydrogen fuel cell through external means. Attached Figure Description

[0046] Figure 1 This is a schematic diagram of the structure of a vehicle insulation fault diagnosis device in the hardware operating environment involved in the embodiments of the present invention;

[0047] Figure 2 This is a flowchart illustrating the first embodiment of the vehicle insulation fault diagnosis method of the present invention;

[0048] Figure 3 This is a schematic diagram of the overall architecture of a hydrogen fuel cell vehicle in one embodiment of the vehicle insulation fault diagnosis method of the present invention;

[0049] Figure 4 This is a flowchart illustrating the second embodiment of the vehicle insulation fault diagnosis method of the present invention;

[0050] Figure 5 This is a flowchart illustrating the third embodiment of the vehicle insulation fault diagnosis method of the present invention;

[0051] Figure 6 This is a structural block diagram of the first embodiment of the vehicle insulation fault diagnosis device of the present invention.

[0052] The realization of the objective, functional features and advantages of the present invention will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0053] It should be understood that the specific embodiments described herein are for illustrative purposes only and are not intended to limit the scope of the invention.

[0054] Reference Figure 1 , Figure 1 This is a schematic diagram of the vehicle insulation fault diagnosis device structure in the hardware operating environment involved in the embodiments of the present invention.

[0055] like Figure 1As shown, the vehicle insulation fault diagnosis device may include: a processor 1001, such as a central processing unit (CPU), a communication bus 1002, a user interface 1003, a network interface 1004, and a memory 1005. The communication bus 1002 is used to enable communication between these components. The user interface 1003 may include a display screen or an input unit such as a keyboard; optionally, the user interface 1003 may also include a standard wired interface or a wireless interface. The network interface 1004 may optionally include a standard wired interface or a wireless interface (such as a Wireless-Fidelity (Wi-Fi) interface). The memory 1005 may be a high-speed random access memory (RAM) or a stable non-volatile memory (NVM), such as a disk drive. The memory 1005 may also optionally be a storage device independent of the aforementioned processor 1001.

[0056] Those skilled in the art will understand that Figure 1 The structure shown does not constitute a limitation on vehicle insulation fault diagnosis equipment and may include more or fewer components than shown, or combine certain components, or have different component arrangements.

[0057] like Figure 1 As shown, the memory 1005, which serves as a storage medium, may include an operating system, a network communication module, a user interface module, and a vehicle insulation fault diagnosis program.

[0058] exist Figure 1 In the vehicle insulation fault diagnosis device shown, the network interface 1004 is mainly used for data communication with the network server; the user interface 1003 is mainly used for data interaction with the user; the processor 1001 and the memory 1005 in the vehicle insulation fault diagnosis device of the present invention can be set in the vehicle insulation fault diagnosis device. The vehicle insulation fault diagnosis device calls the vehicle insulation fault diagnosis program stored in the memory 1005 through the processor 1001 and executes the vehicle insulation fault diagnosis method provided in the embodiment of the present invention.

[0059] This invention provides a method for diagnosing vehicle insulation faults, referring to... Figure 2 , Figure 2 This is a flowchart illustrating the first embodiment of a vehicle insulation fault diagnosis method according to the present invention.

[0060] In this embodiment, the vehicle insulation fault diagnosis method includes the following steps:

[0061] Step S10: When the vehicle is detected to be in a high-voltage state, obtain the first insulation resistance value after the high-voltage power battery system is started, and record the start-up time of the vehicle.

[0062] In this embodiment, the executing entity can be the vehicle insulation fault diagnosis device, which has functions such as data processing, data communication, and program execution. The vehicle insulation fault diagnosis device can be a vehicle controller. Of course, other devices with similar functions can also be used, and this embodiment does not limit this. For ease of explanation, this embodiment uses a vehicle insulation fault diagnosis device as an example.

[0063] This embodiment focuses on a range-extended hydrogen fuel cell vehicle; the specific system structure can be found in [reference needed]. Figure 3 .like Figure 3 As shown, in this embodiment, the vehicle's power source includes a hydrogen fuel cell system and a high-voltage power battery system. Both systems can provide power to the vehicle. The hydrogen fuel cell system includes a hydrogen fuel cell and a hydrogen fuel cell controller (FCU), while the high-voltage power battery system includes a power battery and a power battery controller (BMS). The BMS contains an insulation resistance diagnostic circuit. Both the hydrogen fuel cell system and the high-voltage power battery system are equipped with relays. When the relays are engaged, the corresponding hydrogen fuel cell system and high-voltage power battery system are connected to the high-voltage bus to provide power to the vehicle. At this time, the insulation diagnostic circuit inside the BMS is connected to the vehicle's high-voltage system via the high-voltage bus to obtain the insulation resistance value of the vehicle's high-voltage system. Further, it should be noted that after the vehicle enters a high-voltage-ready state, the BMS first controls the corresponding relay of the high-voltage power battery system to engage, and then the insulation resistance value is obtained through the insulation diagnostic circuit inside the BMS. At this time, only the insulation resistance value of the high-voltage power battery system is included, and this value can be used to diagnose insulation faults in the high-voltage power battery system. To prevent drivers from only briefly entering the vehicle (e.g., to retrieve lost items) and then leaving, and to avoid situations where the State of Charge (SOC) is low during this period, causing the Vehicle Management System (VCM) to request the fuel cell system to start, only to quickly shut it down and purge it, the hydrogen fuel cell system is restarted only after the vehicle has been running for a certain period, such as 1-2 minutes. At this time, the corresponding relay for the hydrogen fuel cell system will also engage. In this scenario, the insulation resistance value obtained through the insulation diagnostic circuit within the Battery Management System (BMS) includes not only the insulation resistance value of the high-voltage power battery system but also that of the hydrogen fuel cell system. It is important to emphasize that the insulation resistance values ​​of both the high-voltage power battery system and the hydrogen fuel cell system change in real time during vehicle operation. This insulation resistance value allows for real-time insulation fault diagnosis of both systems.

[0064] Furthermore, the vehicle controller in the vehicle is used to receive insulation resistance values ​​uploaded by the BMS and issue control commands for relay activation. The vehicle is also equipped with related instrument displays and a connection to a remote server. The vehicle controller can also send insulation fault information to the instrument displays and the remote server.

[0065] It should be noted that range-extended hydrogen fuel cell vehicles have two power sources: a high-voltage power battery system and a hydrogen fuel cell system. Currently, insulation fault diagnosis of hydrogen fuel cells relies on internal parameters of the fuel cell and does not involve the overall insulation fault diagnosis of the hydrogen fuel cell and the high-voltage power battery. In this embodiment, to solve the above technical problem, when the vehicle is detected to be in a high-voltage state, the first insulation resistance value of the high-voltage power battery system after startup is obtained, and the startup time of the vehicle is recorded. Insulation fault diagnosis of the high-voltage power battery system is performed based on the first insulation resistance value. If the high-voltage power battery system does not have an insulation fault, when the startup time reaches a preset time, it is detected whether the hydrogen fuel cell system has started. If it has started, the second insulation resistance value of the hydrogen fuel cell system and the high-voltage power battery system after simultaneous startup is obtained. Insulation fault diagnosis of the hydrogen fuel cell system and the high-voltage power battery system is performed based on the second insulation resistance value. In this way, the overall insulation fault diagnosis of the high-voltage power battery and the hydrogen fuel cell can be performed without diagnosing the internal state of the hydrogen fuel cell. The insulation fault diagnosis of the hydrogen fuel cell can be performed efficiently and quickly through external means. Specifically, it can be implemented as follows.

[0066] In the specific implementation, before performing insulation fault diagnosis, the vehicle needs to be controlled to enter the high-voltage access state. Specifically, the vehicle can enter the high-voltage access state when conditions such as unlocking the door, pressing the brake, and pressing the start button are met. After the vehicle is in the high-voltage access state, a request is sent to the BMS of the high-voltage power battery system. After receiving the request, the BMS controls the relay to engage, so that the high-voltage power battery system is connected to the high-voltage bus. At this time, the high-voltage power battery system starts, and the whole vehicle is in the high-voltage access state. The BMS can obtain the first insulation resistance value and then upload the first insulation resistance value to the vehicle controller. This insulation resistance value does not include the insulation resistance value of the hydrogen fuel cell system. At the same time, this embodiment also records the start-up time of the vehicle in the high-voltage access state for subsequent start-up detection of the hydrogen fuel cell system.

[0067] Step S20: Perform insulation fault diagnosis on the high-voltage power battery system based on the first insulation resistance value.

[0068] It should be noted that since the first insulation resistance value does not include the insulation resistance value of the hydrogen fuel cell system, insulation fault diagnosis of the high-voltage power battery system can be directly performed based on this first insulation resistance value. In an optional embodiment, insulation fault detection of the high-voltage power battery system is achieved by comparing the first insulation resistance value with a first resistance threshold and a second resistance threshold, wherein the first resistance threshold is less than the second resistance threshold, and the specific threshold value can be set according to actual needs; this embodiment does not impose any restrictions on this. Specifically, if the first insulation resistance value is less than the first resistance threshold, it can be determined that the high-voltage power battery system has a high-level insulation fault. In this case, this embodiment enters the vehicle insulation fault emergency power-off process, and simultaneously sends the high-level insulation fault information to the instrument display and the remote server. If the first insulation resistance value is greater than or equal to the first resistance threshold, less than the second resistance threshold, and the duration exceeds a first preset duration, it is determined that the high-voltage power battery system has a low-level insulation fault, and the vehicle insulation fault warning process is entered, simultaneously sending the low-level insulation fault information to the instrument display and the remote server. If the first insulation resistance value is greater than or equal to the second resistance threshold and the duration exceeds the first preset duration, it is determined that the high-voltage power battery system has no insulation fault. Further, after the vehicle is ready for high voltage, the first diagnosis is completed after time T, the second diagnosis is completed after another time T, and so on. The result of each diagnosis, i.e., the insulation resistance value, is sent to the VCM via CAN. During the time interval between the first and second diagnoses, the value sent on CAN remains the result of the first diagnosis until the result is updated after the second diagnosis is completed. Therefore, the aforementioned first preset duration can be set to T, meaning the current diagnosis result is the same as the previous diagnosis result. The specific value can be adjusted according to actual needs.

[0069] Step S30: If there is no insulation fault in the high-voltage power battery system, then when the startup time reaches the preset time, detect whether the hydrogen fuel cell system has started.

[0070] In this implementation, the hydrogen fuel cell system is started only after the high-voltage power battery system has no insulation faults. Specifically, when the startup time reaches a preset duration, it is checked whether the startup conditions of the hydrogen fuel cell system are met. If they are met, the startup of the hydrogen fuel cell system can be requested. Startup conditions include, but are not limited to, a SOC below a certain threshold and no faults in the fuel cell system itself. To avoid the driver only getting into the vehicle for a short stay (such as to retrieve lost items) and then leaving, and to avoid the VCM requesting the fuel cell system to start during this period due to a low SOC, the preset duration can be set to 1-2 minutes. Of course, it can also be adjusted accordingly according to actual needs, and this embodiment does not impose any restrictions on this.

[0071] Step S40: If started, obtain the second insulation resistance value after the hydrogen fuel cell system and the high-voltage power battery system are started simultaneously.

[0072] It should be noted that after the hydrogen fuel cell system is started, the BMS in this embodiment can obtain the second insulation resistance value and then upload the second insulation resistance value to the vehicle controller. This insulation resistance value includes both the insulation resistance value of the hydrogen fuel cell system and the insulation resistance value of the high-voltage power battery.

[0073] Step S50: Perform insulation fault diagnosis on the hydrogen fuel cell system and the high-voltage power battery system based on the second insulation resistance value.

[0074] In practice, since the insulation resistance of the hydrogen fuel cell system and the high-voltage power battery changes in real time during vehicle operation, insulation fault detection of the hydrogen fuel cell system and the high-voltage power battery system is required after the hydrogen fuel cell system is started.

[0075] This embodiment obtains the first insulation resistance value of the high-voltage power battery system after startup when the vehicle is detected to be in a high-voltage state, and records the startup duration of the vehicle; performs insulation fault diagnosis on the high-voltage power battery system based on the first insulation resistance value; if the high-voltage power battery system does not have an insulation fault, then when the startup duration reaches a preset duration, it is detected whether the hydrogen fuel cell system has started; if it has started, a second insulation resistance value is obtained after the hydrogen fuel cell system and the high-voltage power battery system start simultaneously; and insulation fault diagnosis is performed on the hydrogen fuel cell system and the high-voltage power battery system based on the second insulation resistance value. This method enables comprehensive insulation fault diagnosis of both the high-voltage power battery and the hydrogen fuel cell, without needing to diagnose the internal state of the hydrogen fuel cell, allowing for efficient and rapid insulation fault diagnosis of the hydrogen fuel cell through external means.

[0076] refer to Figure 4 , Figure 4 This is a flowchart illustrating a second embodiment of a vehicle insulation fault diagnosis method according to the present invention.

[0077] Based on the first embodiment described above, the vehicle insulation fault diagnosis method of this embodiment includes the following in step S50:

[0078] Step S501: Compare the second insulation resistance value with the first resistance threshold and the second resistance threshold respectively, wherein the first resistance threshold is less than the second resistance threshold.

[0079] In practical implementation, when performing overall insulation fault diagnosis on hydrogen fuel cell systems and high-voltage power battery systems, the second insulation resistance value can be compared with the first resistance threshold and the second resistance threshold respectively.

[0080] Step S502: If the second insulation resistance value is greater than or equal to the second resistance threshold, it is determined that neither the hydrogen fuel cell system nor the high-voltage power battery system has an insulation fault.

[0081] It should be noted that if the second insulation resistance value is greater than or equal to the second resistance threshold, then in this embodiment it can be determined that neither the hydrogen fuel cell system nor the high-voltage power battery system has an insulation fault.

[0082] Step S503: If the second insulation resistance value is greater than or equal to the first resistance threshold and less than the second resistance threshold, and the duration exceeds the first preset duration, then it is determined that the hydrogen fuel cell system and / or the high-voltage power battery system have a low-level insulation fault.

[0083] It should be noted that if the second insulation resistance value is greater than or equal to the first resistance threshold and less than the second resistance threshold, and the duration exceeds the first preset duration, it indicates that the whole vehicle has a low-level insulation fault. It is determined that the hydrogen fuel cell system and / or the high-voltage power battery system have a low-level insulation fault. However, in this case, the whole vehicle insulation fault warning process is entered, and the low-level insulation fault information is sent to the instrument and the remote server. However, it does not affect the vehicle's movement, and the vehicle can still be driven. The settings of the first preset duration, the first resistance threshold, and the second resistance threshold can be referred to the above description, and will not be repeated here.

[0084] Furthermore, if the second insulation resistance value is less than the first resistance threshold, it indicates that the vehicle has a high-level insulation fault. In this case, in this embodiment, it is necessary to obtain a new insulation resistance value to determine the insulation faults corresponding to the hydrogen fuel cell system and the high-voltage power battery system.

[0085] In one optional embodiment, when the second insulation resistance value is less than the first resistance threshold, the vehicle is controlled to enter the emergency power-off process for a vehicle insulation fault, and high-level insulation fault information is sent to the instrument panel and the remote server. After the vehicle is powered down, both the hydrogen fuel cell system and the high-voltage power battery system are disconnected and shut down. Then, the vehicle is restarted and enters the high-voltage state. The third insulation resistance value after the vehicle re-enters the high-voltage state is then obtained. It is easy to understand that after the vehicle enters the high-voltage state, the high-voltage power battery system is started first. At this time, the third insulation resistance value does not include the insulation resistance value of the hydrogen fuel cell system. Based on this third insulation resistance value, insulation fault diagnosis can be performed on the hydrogen fuel cell system and the high-voltage power battery system. Specifically, if the third insulation resistance value is less than the first resistance threshold, it is determined that the high-voltage power battery system has a high-level insulation fault; if the third insulation resistance value is greater than or equal to the first resistance threshold, less than the second resistance threshold, and the duration exceeds the first preset duration, it is determined that the hydrogen fuel cell system has a high-level insulation fault and the high-voltage power battery system has a low-level insulation fault. In this case, the vehicle can travel in EV mode; if the third insulation resistance value is greater than or equal to the second resistance threshold and the duration exceeds the first preset duration, it is determined that the hydrogen fuel cell system has a high-level insulation fault and the high-voltage power battery system does not have an insulation fault. In this case, the vehicle can also travel in EV mode.

[0086] This embodiment compares the second insulation resistance value with a first resistance threshold and a second resistance threshold, respectively, where the first resistance threshold is less than the second resistance threshold. If the second insulation resistance value is greater than or equal to the second resistance threshold, it is determined that neither the hydrogen fuel cell system nor the high-voltage power battery system has an insulation fault. If the second insulation resistance value is greater than or equal to the first resistance threshold but less than the second resistance threshold and the duration exceeds a first preset duration, it is determined that the hydrogen fuel cell system and / or the high-voltage power battery system has a low-level insulation fault. If the second insulation resistance value is less than the first resistance threshold, the vehicle is powered down. After the vehicle is powered down, the vehicle is restarted and enters the high-voltage state. The third insulation resistance value after the vehicle re-enters the high-voltage state is obtained. If the third insulation resistance value is less than the first resistance threshold, then the high-voltage power battery system is determined to have a high-level insulation fault. If the third insulation resistance value is greater than or equal to the first resistance threshold, less than the second resistance threshold, and the duration exceeds the first preset duration, then the hydrogen fuel cell system is determined to have a high-level insulation fault, and the high-voltage power battery system has a low-level insulation fault. If the third insulation resistance value is greater than or equal to the second resistance threshold and the duration exceeds the first preset duration, then the hydrogen fuel cell system is determined to have a high-level insulation fault, and the high-voltage power battery system does not have an insulation fault. By using the above method, after a high-level insulation fault exists in the vehicle, the insulation resistance value obtained by power-down restart is used to accurately diagnose the insulation faults of the hydrogen fuel cell system and the high-voltage power battery system.

[0087] refer to Figure 5 , Figure 5 This is a flowchart illustrating a third embodiment of a vehicle insulation fault diagnosis method according to the present invention.

[0088] Based on the first embodiment described above, a third embodiment of a vehicle insulation fault diagnosis method is proposed.

[0089] In this embodiment, after step S503, the method further includes:

[0090] Step S504: If the second insulation resistance value is less than the first resistance threshold, a shutdown request is sent to the hydrogen fuel cell system to shut down the hydrogen fuel cell system.

[0091] Step S505: Obtain the fourth insulation resistance value after the hydrogen fuel cell system is shut down.

[0092] In specific implementation, in this embodiment, for the case of the whole vehicle being in a high-level insulation fault, it is also possible to only shut down the hydrogen fuel cell system, and after the hydrogen fuel cell system is shut down, obtain the fourth insulation resistance value, and the fourth insulation resistance value does not include the insulation resistance value of the hydrogen fuel cell system.

[0093] Step S506: Perform insulation fault diagnosis on the hydrogen fuel cell system and the high-voltage power battery system based on the fourth insulation resistance value.

[0094] In practical implementation, if the fourth insulation resistance value is less than the first resistance threshold, a high-level insulation fault is determined to exist in the high-voltage power battery system. If the fourth insulation resistance value is greater than or equal to the first resistance threshold, less than the second resistance threshold, and its duration exceeds the second preset duration, a high-level insulation fault is determined to exist in the hydrogen fuel cell system, and a low-level insulation fault is determined to exist in the high-voltage power battery system. In this case, the vehicle can operate in EV mode. If the fourth insulation resistance value is greater than or equal to the second resistance threshold and its duration exceeds the second preset duration, a high-level insulation fault is determined to exist in the hydrogen fuel cell system, and no insulation fault exists in the high-voltage power battery system. In this case, the vehicle can also operate in EV mode. The second preset duration is longer than the first preset duration. When the first preset duration is set to T, the second preset duration can be set to 2T.

[0095] This embodiment uses the following method: if the second insulation resistance value is less than the first resistance threshold, a shutdown request is sent to the hydrogen fuel cell system to shut it down; a fourth insulation resistance value is obtained after the hydrogen fuel cell system is shut down; if the fourth insulation resistance value is less than the first resistance threshold, a high-level insulation fault is determined in the high-voltage power battery system; if the fourth insulation resistance value is greater than or equal to the first resistance threshold, less than the second resistance threshold, and its duration exceeds a second preset duration, a high-level insulation fault is determined in the hydrogen fuel cell system, and a low-level insulation fault is determined in the high-voltage power battery system; if the fourth insulation resistance value is greater than or equal to the second resistance threshold and its duration exceeds the second preset duration, a high-level insulation fault is determined in the hydrogen fuel cell system, and no insulation fault is determined in the high-voltage power battery system, where the second preset duration is greater than the first preset duration. By using the above method, after a high-level insulation fault exists in the entire vehicle, accurate insulation fault diagnosis is performed on the hydrogen fuel cell system and the high-voltage power battery system based on the insulation resistance value obtained by only shutting down the hydrogen fuel cell system.

[0096] Furthermore, this embodiment of the invention also proposes a storage medium storing a vehicle insulation fault diagnosis program, which, when executed by a processor, implements the steps of the vehicle insulation fault diagnosis method described above.

[0097] Since this storage medium adopts all the technical solutions of all the above embodiments, it has at least all the beneficial effects brought about by the technical solutions of the above embodiments, which will not be repeated here.

[0098] Reference Figure 6 , Figure 6 This is a structural block diagram of the first embodiment of the vehicle insulation fault diagnosis device of the present invention.

[0099] like Figure 6 As shown, the vehicle insulation fault diagnosis device proposed in this embodiment of the invention includes:

[0100] The acquisition module 10 is used to acquire the first insulation resistance value of the high-voltage power battery system after startup when the vehicle is detected to be in a high-voltage state, and to record the startup time of the vehicle.

[0101] The diagnostic module 20 is used to perform insulation fault diagnosis on the high-voltage power battery system based on the first insulation resistance value.

[0102] The detection module 30 is used to detect whether the hydrogen fuel cell system has started when the startup time reaches a preset time if there is no insulation fault in the high-voltage power battery system.

[0103] The acquisition module 10 is further configured to acquire, if started, the second insulation resistance value after the hydrogen fuel cell system and the high-voltage power battery system are started simultaneously.

[0104] The diagnostic module 20 is also used to perform insulation fault diagnosis on the hydrogen fuel cell system and the high-voltage power battery system based on the second insulation resistance value.

[0105] This embodiment obtains the first insulation resistance value of the high-voltage power battery system after startup when the vehicle is detected to be in a high-voltage state, and records the startup duration of the vehicle; performs insulation fault diagnosis on the high-voltage power battery system based on the first insulation resistance value; if the high-voltage power battery system does not have an insulation fault, then when the startup duration reaches a preset duration, it is detected whether the hydrogen fuel cell system has started; if it has started, a second insulation resistance value is obtained after the hydrogen fuel cell system and the high-voltage power battery system start simultaneously; and insulation fault diagnosis is performed on the hydrogen fuel cell system and the high-voltage power battery system based on the second insulation resistance value. This method enables comprehensive insulation fault diagnosis of both the high-voltage power battery and the hydrogen fuel cell, without needing to diagnose the internal state of the hydrogen fuel cell, allowing for efficient and rapid insulation fault diagnosis of the hydrogen fuel cell through external means.

[0106] In one embodiment, the diagnostic module 20 is further configured to compare the second insulation resistance value with a first resistance threshold and a second resistance threshold, wherein the first resistance threshold is less than the second resistance threshold; if the second insulation resistance value is greater than or equal to the second resistance threshold, it is determined that neither the hydrogen fuel cell system nor the high-voltage power battery system has an insulation fault; if the second insulation resistance value is greater than or equal to the first resistance threshold and less than the second resistance threshold and the duration exceeds a first preset duration, it is determined that the hydrogen fuel cell system and / or the high-voltage power battery system has a low-level insulation fault.

[0107] In one embodiment, the diagnostic module 20 is further configured to: control the vehicle to power down if the second insulation resistance value is less than the first resistance threshold; control the vehicle to restart and enter the high-voltage state after the vehicle is powered down; obtain the third insulation resistance value after the vehicle re-enters the high-voltage state; and perform insulation fault diagnosis on the hydrogen fuel cell system and the high-voltage power battery system based on the third insulation resistance value.

[0108] In one embodiment, the diagnostic module 20 is further configured to: determine that the high-voltage power battery system has a high-level insulation fault if the third insulation resistance value is less than the first resistance threshold; determine that the hydrogen fuel cell system has a high-level insulation fault and the high-voltage power battery system has a low-level insulation fault if the third insulation resistance value is greater than or equal to the first resistance threshold, less than the second resistance threshold, and the duration exceeds the first preset duration; and determine that the hydrogen fuel cell system has a high-level insulation fault and the high-voltage power battery system does not have an insulation fault if the third insulation resistance value is greater than or equal to the second resistance threshold and the duration exceeds the first preset duration.

[0109] In one embodiment, the diagnostic module 20 is further configured to send a shutdown request to the hydrogen fuel cell system to shut down the hydrogen fuel cell system if the second insulation resistance value is less than the first resistance threshold; obtain a fourth insulation resistance value after the hydrogen fuel cell system is shut down; and perform insulation fault diagnosis on the hydrogen fuel cell system and the high-voltage power battery system based on the fourth insulation resistance value.

[0110] In one embodiment, the diagnostic module 20 is further configured to: determine that the high-voltage power battery system has a high-level insulation fault if the fourth insulation resistance value is less than the first resistance threshold; determine that the hydrogen fuel cell system has a high-level insulation fault and the high-voltage power battery system has a low-level insulation fault if the fourth insulation resistance value is greater than or equal to the first resistance threshold, less than the second resistance threshold, and the duration exceeds a second preset duration; determine that the hydrogen fuel cell system has a high-level insulation fault and the high-voltage power battery system does not have an insulation fault if the fourth insulation resistance value is greater than or equal to the second resistance threshold and the duration exceeds the second preset duration, wherein the second preset duration is greater than the first preset duration.

[0111] In one embodiment, the diagnostic module 20 is further configured to: determine that the high-voltage power battery system has a high-level insulation fault if the first insulation resistance value is less than a first resistance threshold; determine that the high-voltage power battery system has a low-level insulation fault if the first insulation resistance value is greater than or equal to the first resistance threshold, less than a second resistance threshold, and lasts for a duration exceeding a first preset duration; and determine that the high-voltage power battery system does not have an insulation fault if the first insulation resistance value is greater than or equal to the second resistance threshold and lasts for a duration exceeding the first preset duration.

[0112] It should be understood that the above are merely illustrative examples and do not constitute any limitation on the technical solutions of the present invention. In specific applications, those skilled in the art can make settings as needed, and the present invention does not impose any restrictions on this.

[0113] It should be noted that the workflow described above is merely illustrative and does not limit the scope of protection of this invention. In practical applications, those skilled in the art can select some or all of the workflow to achieve the purpose of this embodiment according to actual needs, and no restrictions are imposed here.

[0114] In addition, for technical details not described in detail in this embodiment, please refer to the vehicle insulation fault diagnosis method provided in any embodiment of the present invention, which will not be repeated here.

[0115] Furthermore, it should be noted that, in this document, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or system that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or system. Unless otherwise specified, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or system that includes that element.

[0116] The sequence numbers of the above embodiments of the present invention are for descriptive purposes only and do not represent the superiority or inferiority of the embodiments.

[0117] 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 the present invention, 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 read-only memory (ROM) / RAM, magnetic disk, optical disk) and includes several instructions to cause a terminal device (which may be a mobile phone, computer, server, or network device, etc.) to execute the methods described in the various embodiments of the present invention.

[0118] The above are merely preferred embodiments of the present invention and do not limit the scope of the patent. Any equivalent structural or procedural transformations made based on the description and drawings of the present invention, or direct or indirect applications in other related technical fields, are similarly included within the scope of patent protection of the present invention.

Claims

1. A method for diagnosing vehicle insulation faults, characterized in that, The vehicle includes a hydrogen fuel cell system and a high-voltage power battery system, and the vehicle insulation fault diagnosis method includes: When the vehicle is detected to be in a high-voltage state, the first insulation resistance value of the high-voltage power battery system after startup is obtained, and the startup time of the vehicle is recorded. The high-voltage power battery system is diagnosed for insulation faults based on the first insulation resistance value. If the high-voltage power battery system does not have an insulation fault, then when the startup time reaches the preset time, it is detected whether the hydrogen fuel cell system has started. If started, the second insulation resistance value is obtained after the hydrogen fuel cell system and the high-voltage power battery system are started simultaneously; Insulation fault diagnosis is performed on the hydrogen fuel cell system and the high-voltage power battery system based on the second insulation resistance value. The insulation fault diagnosis of the hydrogen fuel cell system and the high-voltage power battery system based on the second insulation resistance value includes: The second insulation resistance value is compared with the first resistance threshold and the second resistance threshold respectively, wherein the first resistance threshold is less than the second resistance threshold; If the second insulation resistance value is greater than or equal to the second resistance threshold, it is determined that neither the hydrogen fuel cell system nor the high-voltage power battery system has an insulation fault. If the second insulation resistance value is greater than or equal to the first resistance threshold and less than the second resistance threshold, and the duration exceeds the first preset duration, then it is determined that the hydrogen fuel cell system and / or the high-voltage power battery system has a low-level insulation fault. If the second insulation resistance value is less than the first resistance threshold, it is determined that the vehicle has a high-level insulation fault, and the vehicle is powered down; after the vehicle is powered down, the vehicle is restarted and enters the high-voltage state; the third insulation resistance value after the vehicle re-enters the high-voltage state is obtained; and insulation fault diagnosis is performed on the hydrogen fuel cell system and the high-voltage power battery system based on the third insulation resistance value.

2. The vehicle insulation fault diagnosis method as described in claim 1, characterized in that, The insulation fault diagnosis of the hydrogen fuel cell system and the high-voltage power battery system based on the third insulation resistance value includes: If the third insulation resistance value is less than the first resistance threshold, it is determined that the high-voltage power battery system has a high-level insulation fault. If the third insulation resistance value is greater than or equal to the first resistance threshold, less than the second resistance threshold, and the duration exceeds the first preset duration, then it is determined that the hydrogen fuel cell system has a high-level insulation fault and the high-voltage power battery system has a low-level insulation fault. If the third insulation resistance value is greater than or equal to the second resistance threshold and the duration exceeds the first preset duration, then it is determined that the hydrogen fuel cell system has a high-level insulation fault, and the high-voltage power battery system does not have an insulation fault.

3. The vehicle insulation fault diagnosis method as described in claim 1, characterized in that, The vehicle insulation fault diagnosis method also includes: If the second insulation resistance value is less than the first resistance threshold, a shutdown request is sent to the hydrogen fuel cell system to shut down the hydrogen fuel cell system. Obtain the fourth insulation resistance value of the hydrogen fuel cell system after it is powered off; Insulation fault diagnosis is performed on the hydrogen fuel cell system and the high-voltage power battery system based on the fourth insulation resistance value.

4. The vehicle insulation fault diagnosis method as described in claim 3, characterized in that, The insulation fault diagnosis of the hydrogen fuel cell system and the high-voltage power battery system based on the fourth insulation resistance value includes: If the fourth insulation resistance value is less than the first resistance threshold, it is determined that the high-voltage power battery system has a high-level insulation fault. If the fourth insulation resistance value is greater than or equal to the first resistance threshold, less than the second resistance threshold, and the duration exceeds the second preset duration, then it is determined that the hydrogen fuel cell system has a high-level insulation fault and the high-voltage power battery system has a low-level insulation fault. If the fourth insulation resistance value is greater than or equal to the second resistance threshold and the duration exceeds the second preset duration, it is determined that the hydrogen fuel cell system has a high-level insulation fault, the high-voltage power battery system does not have an insulation fault, and the second preset duration is longer than the first preset duration.

5. The vehicle insulation fault diagnosis method according to any one of claims 1 to 4, characterized in that, The insulation fault diagnosis of the high-voltage power battery system based on the first insulation resistance value includes: If the first insulation resistance value is less than the first resistance threshold, it is determined that the high-voltage power battery system has a high-level insulation fault. If the first insulation resistance value is greater than or equal to the first resistance value threshold, less than the second resistance value threshold, and the duration exceeds the first preset duration, then it is determined that the high-voltage power battery system has a low-level insulation fault. If the first insulation resistance value is greater than or equal to the second resistance threshold and the duration exceeds the first preset duration, then it is determined that the high-voltage power battery system does not have an insulation fault.

6. A vehicle insulation fault diagnosis device, characterized in that, The vehicle includes a hydrogen fuel cell system and a high-voltage power battery system, and the vehicle insulation fault diagnosis device includes: The acquisition module is used to acquire the first insulation resistance value of the high-voltage power battery system after startup when the vehicle is detected to be in a high-voltage state, and to record the startup time of the vehicle. The diagnostic module is used to diagnose insulation faults in the high-voltage power battery system based on the first insulation resistance value. The detection module is used to detect whether the hydrogen fuel cell system has started when the startup time reaches a preset time if there is no insulation fault in the high-voltage power battery system. The acquisition module is also used to acquire the second insulation resistance value after the hydrogen fuel cell system and the high-voltage power battery system are started simultaneously if the system is started. The diagnostic module is also used to perform insulation fault diagnosis on the hydrogen fuel cell system and the high-voltage power battery system based on the second insulation resistance value; The diagnostic module is further configured to compare the second insulation resistance value with a first resistance threshold and a second resistance threshold, wherein the first resistance threshold is less than the second resistance threshold; if the second insulation resistance value is greater than or equal to the second resistance threshold, it is determined that neither the hydrogen fuel cell system nor the high-voltage power battery system has an insulation fault; if the second insulation resistance value is greater than or equal to the first resistance threshold and less than the second resistance threshold and the duration exceeds a first preset duration, it is determined that the hydrogen fuel cell system and / or the high-voltage power battery system has a low-level insulation fault; if the second insulation resistance value is less than the first resistance threshold, it is determined that the entire vehicle has a high-level insulation fault, and the vehicle is powered down; after the vehicle is powered down, the vehicle is restarted and enters the high-voltage state; a third insulation resistance value is obtained after the vehicle re-enters the high-voltage state; and insulation fault diagnosis is performed on the hydrogen fuel cell system and the high-voltage power battery system based on the third insulation resistance value.

7. A vehicle insulation fault diagnosis device, characterized in that, The vehicle insulation fault diagnosis device includes: a memory, a processor, and a vehicle insulation fault diagnosis program stored in the memory and running on the processor, the vehicle insulation fault diagnosis program being configured to implement the vehicle insulation fault diagnosis method as described in any one of claims 1 to 5.

8. A storage medium, characterized in that, The storage medium stores a vehicle insulation fault diagnosis program, which, when executed by a processor, implements the vehicle insulation fault diagnosis method as described in any one of claims 1 to 5.

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