Power battery insulation fault protection method and device, vehicle and storage medium

Abstract

The invention relates to power battery safety, in particular to a power battery insulation fault protection method and device, a vehicle and a storage medium, and the method comprises the steps: obtaining an insulation resistance value and current of a high-voltage loop of a power battery in response to the normal voltage of a storage battery of the vehicle and the non-charging state of the whole vehicle; comparing the current with a second preset condition to obtain a comparison result in response to the condition that the acquired insulation resistance meets a first preset condition, and executing a response strategy according to the comparison result; and in response to the condition that the acquired insulation resistance value does not meet the first preset condition, terminating the process. When the high-voltage loop of the power battery has an insulation fault, effective early warning or measure implementation can be realized, and the safety is improved.

Description

Technical Field

[0001] The present invention relates to power battery safety, and in particular to a power battery insulation fault protection method, device, vehicle and storage medium. Background Art

[0002] In recent years, with the rapid development of new energy vehicle technology, market requirements for performance and safety have become increasingly stringent. Real-time monitoring of the insulation performance of the high-voltage system (including key components such as the power battery, drive motor, and DC / DC converter) is crucial within the core architecture of new energy vehicles. This is a key step in preventing the risk of short circuits or electric shock caused by insulation failure. Currently, insulation fault detection mechanisms within the industry are often triggered when the vehicle is charging or driving. However, when the vehicle is in a static, uncharged state, if the insulation resistance and insulation performance decrease due to factors such as humidity, existing mechanisms are unable to issue timely alarms, which directly creates the risk of potential damage to high-voltage components or safety accidents. Summary of the Invention

[0003] The purpose of the present invention is to provide a power battery insulation fault protection method, device, vehicle and storage medium, which can effectively warn or implement measures to improve safety when an insulation fault occurs in the power battery high-voltage circuit.

[0004] In order to achieve the above object, the technical solution adopted by the present invention is as follows: In a first aspect, the present invention discloses a power battery insulation fault protection method, which comprises: In response to the vehicle battery voltage being normal and the vehicle being in a non-charging state, obtaining the insulation resistance and current of the power battery high-voltage circuit; In response to the obtained insulation resistance value meeting the first preset condition, the current is compared with the second preset condition to obtain a comparison result, and a response strategy is executed according to the comparison result; In response to the obtained insulation resistance not meeting the first preset condition, the process is terminated.

[0005] Furthermore, the first preset condition includes that the duration of the insulation resistance value being lower than the first resistance threshold value within the preset period exceeds a first time threshold value; or the duration of the insulation resistance value being lower than the second resistance threshold value within the preset period exceeds a second time threshold value; The first resistance threshold is greater than the second resistance threshold, and the first time threshold is greater than the second time threshold.

[0006] Further, executing a response strategy according to the comparison result includes: disconnecting the power battery high-voltage circuit in response to the current satisfying a second preset condition; In response to the insulation resistance being lower than the first resistance threshold for a duration exceeding a first time threshold within a preset period and the current not meeting a second preset condition, directly reporting an insulation resistance abnormality fault; In response to the insulation resistance being lower than the second resistance threshold for a duration exceeding the second time threshold for a number of times exceeding the preset number of times within the preset period, an insulation resistance abnormality fault is reported.

[0007] Furthermore, the second preset condition includes that the duration of the current exceeding the current threshold exceeds a third time threshold.

[0008] Furthermore, the insulation resistance of the power battery high-voltage circuit is obtained through an insulation detection module arranged inside the battery pack, and the current of the power battery high-voltage circuit is obtained through a current sensor arranged inside the battery pack.

[0009] Furthermore, the insulation detection module can also obtain the insulation resistance of the connection port, and in response to the insulation resistance of the connection port being lower than the third resistance threshold for a duration exceeding the fourth time threshold, determine that the connection status of the power battery is abnormal; otherwise, determine that the connection status of the power battery is normal.

[0010] Furthermore, the connection port includes a first port connected to a charging device and a second port connected to an electrical device; and the insulation detection module is connected in series with the first port and the second port.

[0011] In a second aspect, the present invention discloses a power battery insulation fault protection device, which includes: an acquisition unit, in response to the vehicle battery voltage being normal and the vehicle being in a non-charging state, acquiring the insulation resistance and current of the power battery high-voltage circuit; a first execution unit, in response to the obtained insulation resistance value meeting the first preset condition, comparing the current with the second preset condition to obtain a comparison result, and executing a response strategy according to the comparison result; The second execution unit terminates the process in response to the obtained insulation resistance value not meeting the first preset condition.

[0012] In a third aspect, the present invention discloses a vehicle, including a power battery assembly, wherein the power battery assembly includes the above-mentioned power battery insulation fault protection device.

[0013] In a fourth aspect, the present invention discloses a storage medium having a computer program stored thereon, which implements the steps of the above-mentioned power battery insulation fault protection method when executed by a processor.

[0014] The present invention has the following unexpected beneficial effects: The power battery insulation fault protection method reduces the false alarm rate for insulation faults and improves detection accuracy. By employing a dual-layer judgment logic that compares the current with a second preset condition after the insulation resistance meets a first preset condition, compared to the existing method that relies solely on threshold detection, this method adds current as a reference dimension, enabling comprehensive multi-parameter analysis. This reduces the possibility of false alarms caused by fluctuations in a single parameter, eliminates the need for backend screening or waiting for the entire vehicle to fail before processing, and improves the reliability of insulation fault diagnosis. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] In order to more clearly illustrate the specific implementation of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the implementation or prior art description. Obviously, the drawings described below are only some embodiments of the present invention.

[0016] Figure 1 A schematic diagram showing a flow chart of an embodiment of a power battery insulation fault protection method provided by the present invention; Figure 2 A schematic flow chart showing another embodiment of the power battery insulation fault protection method provided by the present invention; Figure 3 The figure shows a schematic structural diagram of the power battery insulation fault protection device provided by the present invention; Figure 4 A schematic diagram of a vehicle high-voltage architecture provided by the present invention is shown. DETAILED DESCRIPTION

[0017] The following describes the embodiments of the present invention with reference to the accompanying drawings and preferred embodiments. Those skilled in the art will readily appreciate the other advantages and benefits of the present invention from the disclosure herein. The present invention may also be implemented or applied through various other specific embodiments, and the various details in this specification may be modified or altered based on different viewpoints and applications without departing from the spirit of the present invention. It should be understood that the preferred embodiments are intended only to illustrate the present invention and are not intended to limit the scope of protection of the present invention.

[0018] In one embodiment, see Figure 1 As shown, the present invention provides a power battery insulation fault protection method, which includes: In response to the vehicle battery voltage being normal and the entire vehicle being in a non-charging state, the insulation resistance and current of the power battery high-voltage circuit are obtained.

[0019] In response to the obtained insulation resistance value meeting the first preset condition, the current is compared with the second preset condition to obtain a comparison result, and a response strategy is executed according to the comparison result.

[0020] In response to the obtained insulation resistance not meeting the first preset condition, the process is terminated.

[0021] The power battery insulation fault protection method described in this invention reduces the false alarm rate for insulation faults and improves detection accuracy. This dual-layer judgment logic, which compares the current with a second preset condition after the insulation resistance meets a first preset condition, adds current as a reference dimension, compared to the existing method that relies solely on threshold detection, enabling comprehensive multi-parameter analysis. This reduces the possibility of false alarms caused by fluctuations in a single parameter, eliminates the need for backend screening or waiting for a complete vehicle fault to occur before processing, and improves the reliability of insulation fault diagnosis.

[0022] The low-voltage battery serves as the starting and control power source for the power battery system. Its primary functions include powering the high-voltage system's control modules (such as the BMS, battery management system), insulation detection circuits, relays, and other low-voltage components. It also controls the high-voltage system's power-up process (e.g., waking up the BMS and activating high-voltage relays). When the vehicle is turned off or the high-voltage system is disconnected, it maintains low-power operation of key modules (e.g., storing fault codes and maintaining the real-time clock). Abnormal low-voltage battery voltage (undervoltage or overvoltage) can directly impact the stability of these core functions.

[0023] In this embodiment, the power battery insulation fault protection method described in the present invention first detects the battery voltage to ensure the accuracy of insulation detection. The acquisition of insulation resistance relies on a precision insulation resistance detection module in the low-voltage circuit, such as an insulation monitor IMD, which works by injecting a specific detection signal into the high-voltage circuit to calculate the insulation resistance of the circuit to the ground. If the battery is undervoltage, the insulation resistance detection module may cause a decrease in signal generation accuracy due to insufficient power supply, misjudge the insulation resistance, or cause the sampling circuit to work unstably, with data jumps or no output. If the battery is overvoltage, it may exceed the power supply range of the insulation resistance detection module, causing circuit damage or detection logic disorder, and it is also impossible to obtain reliable data. Therefore, only when the battery voltage is normal can the detection module be in a stable working state to ensure that the acquisition of insulation resistance is accurate and effective.

[0024] Moreover, if the battery voltage is abnormal, it is essentially a low-voltage power supply system failure. At this time, even if the insulation resistance is abnormal, it may be a derivative result of the power supply problem rather than a failure of the insulation itself.

[0025] In electric vehicle insulation testing, the acquisition of power battery insulation resistance values ​​is limited to the non-charging state. This is to prevent external factors (especially the insulation status of the charging pile) from interfering with the test results during charging, ensuring the accuracy of insulation fault detection. When the vehicle is charging, whether using DC fast charging or AC slow charging, the power battery system forms an electrical connection circuit with the external charging pile through the charging port. This fundamentally changes the insulation testing environment of the system: the previously independent power battery high-voltage circuit is now connected to the internal circuit of the charging pile via the charging cable, forming an extended circuit consisting of power battery, charging cable, and charging pile. If the power battery insulation is forcibly tested during charging, the test signal may penetrate the charging pile, causing the detection range to exceed the designed boundaries. Similarly, if the charging pile has poor insulation, such as a live charging pile housing or a short-circuit at the output terminal to ground, the fault condition will be transmitted to the vehicle's high-voltage circuit through the cable during charging. In this case, the power battery insulation detection module may mistakenly identify the charging pile insulation fault as a vehicle system insulation fault, resulting in a meaningless false alarm. Furthermore, aging or damage to the charging cable insulation layer, or water ingress to the plug, can cause the cable's insulation resistance to decrease. When charging, these insulation problems will be included in the sampling range of the on-board detection system, causing the insulation resistance detection module to mistakenly judge that the power battery or electric drive system has poor insulation, while the actual fault point is in the external cable.

[0026] Power battery insulation testing typically involves injecting a low-frequency signal and performing sampling calculations. However, the internal circuitry of charging piles can generate high-frequency noise or co-frequency interference signals. These signals can overlap with the onboard test signals, distorting the sampled data and ultimately causing errors in insulation resistance calculations.

[0027] Therefore, insulation testing of the power battery system can only meet the following conditions when the battery is not charging, that is, when the charging port is disconnected and the onboard high-voltage circuit is completely isolated from external devices: 1) Clear testing scope: This only targets the power battery high-voltage circuit, eliminating interference from external devices. 2) Independent signal path: The test signal is transmitted only within the onboard circuit, and the calculation results will not be affected by impedance changes in the external circuit. 3) Clear fault responsibility: If an insulation anomaly is detected at this time, it can be directly identified as a problem with the onboard system, avoiding confusion with external factors such as charging piles and cables, and facilitating troubleshooting.

[0028] As a preferred embodiment of the present invention, see Figure 2 As shown, the first preset condition includes that the duration of the insulation resistance value being lower than the first resistance threshold value within the preset period exceeds the first time threshold value; or the duration of the insulation resistance value being lower than the second resistance threshold value within the preset period exceeds the second time threshold value; the first resistance threshold value is greater than the second resistance threshold value, and the first time threshold value is greater than the second time threshold value.

[0029] In this preferred embodiment, the first preset condition includes the insulation resistance R within the preset period. A The duration t below the first resistance threshold R1 A Exceeding the first time threshold t1 is suitable for a slight insulation drop scenario. For example, the first resistance threshold R1 is set to 2100kΩ, and the first time threshold t1 is set to 15 minutes. If the insulation resistance R A If the resistance is lower than 2100kΩ for a long time (more than 15 minutes), it indicates that the insulation layer may be slowly aging. The system can provide early warning of insulation performance degradation and prompt the user to perform preventive maintenance.

[0030] The insulation resistance R within the preset period of the first preset condition A The duration t below the second resistance threshold R2 A Exceeding the second time threshold t2 applies to severe insulation fault scenarios. For example, the second resistance threshold is set to 1100kΩ and the second time threshold is set to 30 seconds. If the insulation resistance remains below 1100kΩ for 30 seconds, it indicates a potential instantaneous breakdown or severe leakage. The system must immediately report an insulation fault and trigger protection measures, such as shutting off the high-voltage circuit, to avoid the risk of electric shock or fire.

[0031] This preferred implementation method uses hierarchical judgment, and the system can not only identify potential hidden dangers, but also quickly respond to emergency failures, realizing full-chain management from early warning to protection.

[0032] It should be noted that the insulation detection signal may be affected by vehicle vibration, electromagnetic interference or glitches in the detection circuit, resulting in short-term resistance jumps, such as momentarily falling below the threshold but the actual insulation is normal. The "long duration" of the first time threshold can filter out slight interference: even if the power battery insulation resistance drops temporarily due to interference, as long as it does not continue to exceed the first time threshold, the system will not determine it as a fault, avoiding frequent warnings that affect user experience. The "short duration" of the second time threshold can exclude instantaneous spike interference: only when the obtained power battery insulation resistance continues to be lower than the critical value for more than the second time threshold is the fault confirmed, which not only ensures a rapid response in an emergency, but also prevents false operations caused by occasional interference, such as suddenly cutting off high voltage while driving. This differentiated design of time thresholds balances detection sensitivity and anti-interference capability.

[0033] As a preferred embodiment of the present invention, see Figure 2As shown, the response strategy executed based on the comparison results includes: disconnecting the power battery high-voltage circuit in response to the current meeting the second preset condition. This response strategy essentially treats current anomalies as the highest priority safety trigger signal. Current is a direct reflection of the energy flow in the high-voltage circuit. If the current is abnormal, it often means that the insulation fault has progressed to the stage of substantial leakage. At this point, the leakage energy may cause electric shock, component burns, or even fire, which is the highest risk level. Compared to the potential risk signal of decreased insulation resistance, current anomalies are an immediate danger signal. By prioritizing the high-voltage circuit, the energy source can be quickly cut off, physically preventing the risk from escalating and ensuring the safety of the entire vehicle.

[0034] For the two scenarios of abnormal insulation resistance, the strategy realizes risk classification through the difference design of direct reporting and cumulative reporting. Specifically, in response to the duration of the insulation resistance value lower than the first resistance threshold value for more than the first time threshold within the preset period, and the current does not meet the second preset condition, the insulation resistance abnormality fault is directly reported, prompting active maintenance. For example; the insulation resistance value R A If the resistance remains below 2100kΩ for an extended period (over 15 minutes) but the current does not reach the abnormal threshold, it indicates noticeable insulation degradation. Reporting the fault immediately alerts users or maintenance personnel to potential insulation aging or moisture, promoting preventative maintenance and preventing further damage from untimely resolution.

[0035] In response to the insulation resistance being lower than the second resistance threshold for a period of time exceeding the second time threshold for more than the preset number of times within the preset period, an insulation resistance abnormality fault is reported. That is, the report is made after cumulative judgment, filtering out occasional interference. For scenarios where the insulation resistance is temporarily lower than the second resistance threshold, the response strategy is set to report only when the number of times exceeds the preset number. The core is to distinguish occasional interference from continuous hidden dangers. The insulation resistance R within the preset period may be caused by vibration or electromagnetic interference during vehicle driving. A Short-term transients, such as a resistance below 1100kΩ for 40 seconds when insulation is actually normal, can easily lead to false alarms if reported as a single occurrence, potentially affecting user confidence. Only when such short-term anomalies occur repeatedly are they considered to indicate insulation instability. Reporting the fault at this time prevents missed detections and ensures a more rigorous assessment.

[0036] As a preferred embodiment of the present invention, the second preset condition includes that the duration that the current exceeds the current threshold exceeds a third time threshold.

[0037] In this preferred embodiment, current overlimit and continuous timeout are used as dual judgment conditions, rather than just instantaneous current overlimit as the trigger basis, which avoids false protection caused by instantaneous interference and improves system stability. In the vehicle's high-voltage circuit, instantaneous current overlimit may be caused by non-fault factors, such as instantaneous impact current during motor startup or rapid acceleration, or current fluctuations when high-voltage components switch working states, which may exceed the conventional threshold for a short time, but belong to normal working conditions; if only the current exceeding the threshold is used as the trigger condition, such instantaneous fluctuations are easily misjudged as leakage or short-circuit faults, resulting in frequent disconnection of the high-voltage circuit, seriously affecting vehicle availability and user experience. By setting the duration of the current exceeding the current threshold to exceed the third time threshold, that is, by setting a time buffer, such instantaneous, harmless current fluctuations can be filtered out, and only respond to the current that continuously exceeds the limit, reducing false protection from the source and improving the accuracy of system judgment.

[0038] Integrating the logic of insulation resistance grading in the aforementioned preferred embodiment, the inclusion of a continuous current exceeding the limit as the second precondition corresponds to the development stage of the insulation fault. When the insulation fault is minor, such as a slight drop in insulation resistance without breakdown, the leakage current is typically small and unstable, making it difficult to meet the continuous current exceeding limit condition. Therefore, high-voltage disconnection is not triggered, and the fault is only reported via the insulation resistance abnormality strategy, ensuring basic vehicle operation. When the insulation fault worsens, such as insulation breakdown or severe aging, the leakage current increases and stabilizes. At this point, the continuous current exceeding limit condition is triggered, immediately disconnecting the high-voltage circuit, forming a progressive protection chain from minor fault warning to severe fault disconnection.

[0039] This setting allows current protection and insulation resistance protection to complement each other. That is, insulation resistance monitoring is responsible for early warning, and continuous current over-limit monitoring is responsible for emergency loss prevention. The combination of the two makes the protection logic more in line with the objective laws of fault development, thereby improving the safety and logic of the system.

[0040] As a preferred embodiment of the present invention, see Figure 4 As shown, the insulation resistance of the power battery high-voltage circuit is obtained by the insulation detection module 21 arranged inside the battery pack 20, and the current of the power battery high-voltage circuit is obtained by the current sensor 22 arranged inside the battery pack 20.

[0041] The insulation state and current signal of the power battery's high-voltage circuit are easily affected by external factors (such as wiring harness length and electromagnetic interference). However, integrating the detection element internally optimizes signal quality from the source. Testing the power battery's insulation resistance relies on accurate measurement of the high-voltage circuit's impedance to ground. If the insulation detection module is external, such as installed in a high-voltage distribution box or vehicle body wiring harness, it must be connected to the power battery via a long, high-voltage wiring harness. The insulation performance of the wiring harness itself (such as aging and moisture) may be included in the detection range, leading to the misidentification of wiring harness insulation problems as internal battery pack faults. By integrating the insulation detection module 21 into the battery pack 20, the insulation detection module 21 can directly detect the insulation resistance of the power battery's high-voltage circuit within the battery pack 20, eliminating interference from external wiring harnesses and ensuring that the detection object is focused on the power battery itself, making the data more accurate.

[0042] Current signal acquisition requires extremely short paths and minimal interference. If the current sensor is external, the high current in the high-voltage main circuit will generate strong electromagnetic radiation in the wiring harness, interfering with the current sensor's sampling accuracy. Once built into the battery pack 20, the current sensor 22 can be directly mounted on the main circuit busbar inside the battery pack, closer to the current source. This shortens the signal transmission path, reduces electromagnetic interference, and ensures the authenticity of the current data.

[0043] Furthermore, if the insulation detection module 21 or current sensor 22 were external, they would need to be connected to the battery pack via additional high-voltage cables, increasing the number of high-voltage interfaces. If these interfaces are poorly sealed, loose, or aged, they could become new insulation weaknesses or leakage risks. An internal design, however, directly integrates the detection elements—the insulation detection module 21 and current sensor 22—with the internal high-voltage circuit of the battery pack 20, reducing the number of external high-voltage interfaces and mitigating safety risks caused by connection component failures.

[0044] As a preferred embodiment of the present invention, the insulation detection module 21 can also obtain the insulation resistance of the connection port, and in response to the insulation resistance of the connection port being lower than the third resistance threshold for a duration exceeding the fourth time threshold, it is determined that the connection status of the power battery is abnormal; otherwise, it is determined that the connection status of the power battery is normal.

[0045] Connection ports (such as high-voltage plug-ins and busbar connectors) are the weak links in the high-voltage circuit of power batteries. Traditional insulation testing focuses mainly on the overall insulation status of the circuit and cannot specifically identify port-level faults. For example, vibration, frequent plugging and unplugging, or improper installation may cause oxidation and loosening of the port contact surface, forming high-resistance points, causing local heating and even arcing. For another example, aging or damage to the port sealing ring may cause water and dust to enter, reducing insulation performance. This preferred embodiment independently monitors the port insulation resistance, allowing the system to provide timely warnings in the early stages of a fault, preventing it from developing into a serious short circuit or arcing fault.

[0046] As a preferred embodiment of the present invention, see Figure 4 As shown, the connection port includes a first port 23 connected to the charging device 30 and a second port 24 connected to the power device; the insulation detection module 22 is connected in series with the first port 23 and the second port 24.

[0047] The first port 23, the charging device connection, is exposed to the external environment for extended periods, making it susceptible to insulation degradation due to water ingress, dust accumulation, and wear and tear during insertion and removal. Failures are often related to the charging process. The second port 24, the power device connection, connects to high-voltage components onboard, such as the electric drive assembly 40 and the compressor 50. Operating in the enclosed space of the vehicle, it is susceptible to vibration, high temperatures, or wiring harness pulls, potentially leading to insulation aging and loose connectors. Failures are often related to driving.

[0048] When connected in series with the first port 23 and the second port 24, the insulation detection module 21 can identify insulation anomalies at specific ports through voltage division or signal path differences. For example, after injecting a detection signal into the series circuit, if only the signal feedback from the first port is abnormal, it can be determined to be a charging port insulation problem; if only the signal from the second port is abnormal, it can be located as a fault at the power device connection terminal. This independent monitoring avoids the drawback of traditional integrated detection, where two port faults cannot be distinguished, and allows fault location to be accurately determined from the system level to the port level.

[0049] See also Figure 4 As shown, the high-voltage circuit of the power battery within the battery pack 20 is also equipped with a fuse 25 and a relay 26. When a short circuit in the high-voltage circuit (e.g., a damaged wiring harness or internal short circuit in the battery module) generates a current far exceeding the design threshold, the fuse 25 will quickly fuse, actively disconnecting the faulty circuit. The relay 26 is used to close or disconnect the high-voltage circuit of the power battery. The charging device 30 includes a DC charging port 31 connected to the power battery within the battery pack and an AC charging port 42 connected to the inverter 41 within the electric drive assembly 40.

[0050] In one embodiment, the present invention discloses a power battery insulation fault protection device, see Figure 3 As shown, the protection device 10 includes an acquisition unit 11, a first execution unit 12, and a second execution unit 13. In response to the vehicle battery voltage being normal and the vehicle being in a non-charging state, the acquisition unit 11 acquires the insulation resistance and current of the power battery high-voltage circuit. In response to the acquired insulation resistance satisfying a first preset condition, the first execution unit 12 compares the current with a second preset condition, obtains a comparison result, and executes a response strategy based on the comparison result. In response to the acquired insulation resistance not satisfying the first preset condition, the second execution unit 13 terminates the process.

[0051] In one embodiment, the present invention discloses a vehicle including a power battery assembly, wherein the power battery assembly includes the power battery insulation fault protection device described above.

[0052] It should be noted that the vehicle may be, but is not limited to, a pure electric vehicle (Pure Electric Vehicle / Battery Electric Vehicle, PEV / BEV), a hybrid electric vehicle (Hybrid Electric Vehicle, HEV), a range extended electric vehicle (Range Extended Electric Vehicle, REEV), a plug-in hybrid electric vehicle (Plug-in Hybrid Electric Vehicle, PHEV), etc.

[0053] In one embodiment, the present invention discloses a storage medium having a computer program stored thereon. When the computer program is executed by a processor, the steps of the above-mentioned power battery insulation fault protection method are implemented.

[0054] In the several embodiments provided in this application, it should be understood that the disclosed devices and methods can be implemented in other ways. The device embodiments described above are merely schematic. For example, the division of the units is merely a logical function division. In actual implementation, there may be other division methods, such as: multiple units or components can be combined, or can be integrated into another system, or some features can be ignored or not executed. In addition, the coupling, direct coupling, or communication connection between the components shown or discussed can be through some interfaces, indirect coupling or communication connection of devices or units, which can be electrical, mechanical or other forms.

[0055] The units described above as separate components may or may not be physically separated, and the components displayed as units may or may not be physical units; they may be located in one place or distributed across multiple network units; some or all of the units may be selected according to actual needs to achieve the purpose of the scheme of this embodiment.

[0056] In addition, all functional units in the embodiments of the present application can be integrated into one processing unit, or each unit can be a separate unit, or two or more units can be integrated into one unit; the above-mentioned integrated units can be implemented in the form of hardware or in the form of hardware plus software functional units.

[0057] Those skilled in the art will understand that all or part of the steps of the above-mentioned method embodiment can be completed by hardware related to program instructions, and the aforementioned program can be stored in a computer-readable storage medium. When the program is executed, it executes the steps of the above-mentioned method embodiment; and the aforementioned storage medium includes: mobile storage devices, read-only memories (ROM), magnetic disks or optical disks, and other media that can store program codes.

[0058] Alternatively, if the above-mentioned integrated unit of the present application is implemented in the form of a software functional module and sold or used as an independent product, it can also be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present application, or the part that contributes to the relevant technology, can be embodied in the form of a software product. The computer software product is stored in a storage medium and includes a number of instructions for enabling an electronic device (which can be a personal computer, server, or network device, etc.) to execute all or part of the methods described in the various embodiments of the present application. The aforementioned storage medium includes: various media that can store program code, such as mobile storage devices, ROMs, magnetic disks, or optical disks.

[0059] The above is only an implementation method of the present application, but the scope of protection of the present application is not limited thereto. Any technician familiar with this technical field can easily think of changes or replacements within the technical scope disclosed in this application, which should be covered by the scope of protection of the present application.

Claims

1. A power battery insulation fault protection method, characterized in that: include: In response to the vehicle battery voltage being normal and the vehicle being in a non-charging state, obtaining the insulation resistance and current of the power battery high-voltage circuit; In response to the obtained insulation resistance value meeting the first preset condition, the current is compared with the second preset condition to obtain a comparison result, and a response strategy is executed according to the comparison result; In response to the obtained insulation resistance not meeting the first preset condition, the process is terminated.

2. The power battery insulation fault protection method according to claim 1, characterized in that: The first preset condition includes that the duration of the insulation resistance value being lower than the first resistance threshold value within the preset period exceeds a first time threshold value; or the duration of the insulation resistance value being lower than the second resistance threshold value within the preset period exceeds a second time threshold value; The first resistance threshold is greater than the second resistance threshold, and the first time threshold is greater than the second time threshold.

3. The power battery insulation fault protection method according to claim 1, characterized in that: Executing a response strategy based on the comparison result includes: disconnecting the power battery high-voltage circuit in response to the current satisfying a second preset condition; In response to the insulation resistance being lower than the first resistance threshold for a duration exceeding a first time threshold within a preset period and the current not meeting a second preset condition, directly reporting an insulation resistance abnormality fault; In response to the insulation resistance being lower than the second resistance threshold for a duration exceeding the second time threshold for a number of times exceeding the preset number of times within the preset period, an insulation resistance abnormality fault is reported.

4. The power battery insulation fault protection method according to claim 1, characterized in that: The second preset condition includes a duration in which the current exceeds the current threshold value exceeding a third time threshold value.

5. The power battery insulation fault protection method according to claim 1, characterized in that: The insulation resistance of the power battery high-voltage circuit is obtained through the insulation detection module arranged inside the battery pack, and the current of the power battery high-voltage circuit is obtained through the current sensor arranged inside the battery pack.

6. The power battery insulation fault protection method according to claim 5, characterized in that: The insulation detection module can also obtain the insulation resistance of the connection port, and in response to the insulation resistance of the connection port being lower than the third resistance threshold for a duration exceeding the fourth time threshold, determine that the connection status of the power battery is abnormal; otherwise, determine that the connection status of the power battery is normal.

7. The power battery insulation fault protection method according to claim 6, characterized in that: The connection port includes a first port connected to a charging device and a second port connected to an electric device; The insulation detection module is connected in series with the first port and the second port.

8. A power battery insulation fault protection device, characterized in that: include: an acquisition unit, in response to the vehicle battery voltage being normal and the vehicle being in a non-charging state, acquiring the insulation resistance and current of the power battery high-voltage circuit; a first execution unit, in response to the obtained insulation resistance value meeting the first preset condition, comparing the current with the second preset condition to obtain a comparison result, and executing a response strategy according to the comparison result; The second execution unit terminates the process in response to the obtained insulation resistance value not meeting the first preset condition.

9. A vehicle comprising a power battery assembly, characterized in that: The power battery assembly includes the power battery insulation fault protection device as claimed in claim 8.

10. A storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the steps of the power battery insulation fault protection method according to any one of claims 1 to 7 are implemented.

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