Power battery current detection method and device and vehicle

Abstract

The invention provides a power battery current detection method, a power battery current detection device and a vehicle, which are used for providing power battery current meeting functional safety. A first current sensor and a second current sensor which are different in acquisition precision are arranged in a power battery high-voltage loop. The power battery current detection method comprises the following steps: acquiring a first channel current and a second channel current which are respectively acquired by the first sensor and the second sensor; acquiring physical failure states of the first sensor and the second sensor; when the first sensor and the second sensor do not physically fail, determining data failure states of the first sensor and the second sensor according to the first channel current and the second channel current; and according to the first channel current, the second channel current, the physical failure state of the first sensor, the physical failure state of the second sensor, the data failure state of the first sensor and the data failure state of the second sensor, outputting the power battery current meeting the function safety requirement.

Description

Technical Field

[0001] The present invention is applied to the technical field of power batteries for new energy vehicles, and more specifically relates to a power battery current detection method, device, and vehicle. Background Art

[0002] With the rapid development of new energy vehicles, their safety has become a major concern. Prolonged battery overcharging can easily lead to overheating and, in severe cases, fire and explosion, severely impacting both the vehicle and personnel. Currently, most current monitoring methods rely on single-channel current detection. This is due to the high probability of failure and potential deviations in acquisition accuracy, making it impossible to accurately monitor actual current. A small number of battery management systems equipped with functional safety utilize dual-channel current detection. However, this dual-channel approach lacks detailed analysis and processing of each operating condition in the event of anomalies or discrepancies between the two channels, which can easily lead to current mishandling and failure to meet functional safety requirements. Summary of the Invention

[0003] The present invention provides a power battery current detection method, device and vehicle, for providing a power battery current that meets functional safety requirements.

[0004] The technical solution of the present invention is: The present application provides a power battery current detection method, in which a first current sensor and a second current sensor with different acquisition accuracy are arranged in a high-voltage circuit of the power battery. The power battery current detection method includes: Acquire a first channel current and a second channel current respectively collected by the first sensor and the second sensor; Acquiring a physical failure status of the first sensor and the second sensor; When neither the first sensor nor the second sensor is physically failed, determining data failure states of the first sensor and the second sensor according to the first channel current and the second channel current; Output a power battery current that meets functional safety requirements based on the first channel current, the second channel current, the physical failure state of the first sensor, the physical failure state of the second sensor, the data failure state of the first sensor, and the data failure state of the second sensor.

[0005] Preferably, the acquisition accuracy of the first sensor is higher than that of the second sensor.

[0006] Preferably, when neither the first sensor nor the second sensor is physically failed, the step of determining the data failure status of the first sensor and the second sensor according to the first channel current and the second channel current includes: determining a maximum error difference between the first sensor and the second sensor according to a preset acquisition error range of the first sensor and a preset acquisition error range of the second sensor; determining a current difference between the first channel current and the second channel current; If the current difference exceeds the maximum error difference, it is determined that the data of the first sensor and the second sensor are invalid; otherwise, it is determined that the data of the first sensor and the second sensor are not invalid.

[0007] Preferably, the step of outputting a power battery current that meets functional safety requirements according to the first channel current, the second channel current, the physical failure state of the first sensor, the physical failure state of the second sensor, the data failure state of the first sensor, and the data failure state of the second sensor includes: If one of the first sensor and the second sensor is physically invalid and the other is physically valid, the current output is performed according to the physically valid sensor; If both the first sensor and the second sensor are physically failed, the current output is performed according to the effective current output last time; If both the first sensor and the second sensor are physically valid, data of the first sensor and the second sensor are invalid, and the first channel current and the second channel current are of the same type, outputting the current according to the larger value of the first channel current and the second channel current; If the first sensor and the second sensor are both physically valid, data of the first sensor and the second sensor are invalid, and the first channel current and the second channel current are different types of current, outputting current of corresponding types according to the first channel current and the second channel current; If the first sensor and the second sensor are both physically valid and the data of the first sensor and the second sensor are not invalid, the current is output according to the first channel current.

[0008] Preferably, if one of the first sensor and the second sensor is physically invalid and the other is physically valid, the step of outputting current according to the physically valid sensor includes: If the first sensor is not physically failed, the second sensor is physically failed, and the first channel current is a charging current, the first channel current is output as the charging current, and the discharge current is set to 0; If the first sensor is not physically failed, the second sensor is physically failed, and the first channel current is a discharge current, the first channel current is output as the discharge current, and the charging current is set to 0; If the first sensor fails physically, the second sensor does not fail physically, and the second channel current is a charging current, the second channel current is output as the charging current, and the discharge current is set to 0; If the first sensor physically fails, the second sensor does not physically fail, and the second channel current is a discharge current, the second channel current is output as the discharge current, and the charging current is set to 0.

[0009] Preferably, if the first sensor and the second sensor are both physically valid, data of the first sensor and the second sensor are invalid, and the first channel current and the second channel current are of the same type, the step of outputting current according to the larger value of the first channel current and the second channel current includes: If both the first sensor and the second sensor are physically valid, the data of the first sensor and the second sensor are invalid, and both the first channel current and the second channel current are charging currents, the larger value of the first channel current and the second channel current is output as the charging current, and the discharging current is set to 0; If the first sensor and the second sensor are both physically valid, the data of the first sensor and the second sensor are invalid, and the first channel current and the second channel current are both discharge currents, the discharge current is output according to the larger value of the first channel current and the second channel current, and the charging current is set to 0.

[0010] Preferably, if the first sensor and the second sensor are both physically valid, data of the first sensor and the second sensor are invalid, and the first channel current and the second channel current are different types of current, the step of outputting current of corresponding types according to the first channel current and the second channel current includes: If both the first sensor and the second sensor are physically valid, data of the first sensor and the second sensor are invalid, and the first channel current is a charging current and the second channel current is a discharging current, the charging current is output according to the first channel current, and the discharging current is output according to the second channel current; If the first sensor and the second sensor are both physically valid, the data of the first sensor and the second sensor are invalid, and the first channel current is a discharge current and the second channel current is a charge current, the discharge current is output according to the first channel current, and the charging current is output according to the second channel current.

[0011] Preferably, if both the first sensor and the second sensor are physically valid and data of both the first sensor and the second sensor are valid, the step of outputting current according to the first channel current includes: The first sensor and the second sensor are both physically valid, data of the first sensor and the second sensor are not invalid, and the first channel current is a charging current. The first channel current is output as the charging current, and the discharge current is set to 0; The first sensor and the second sensor are both physically valid, data of the first sensor and the second sensor are both valid, and the first channel current is a discharge current. The first channel current is output as the discharge current, and the charging current is set to 0.

[0012] The present application also provides a power battery current detection device, in which a first current sensor and a second current sensor with different acquisition accuracy are arranged in a high-voltage circuit of the power battery. The power battery current detection device includes: An acquisition module, configured to acquire a first channel current and a second channel current respectively acquired by the first sensor and the second sensor; a failure status module, configured to obtain the physical failure status of the first sensor and the second sensor; a data failure state determining module, configured to determine the data failure state of the first sensor and the second sensor according to the first channel current and the second channel current when neither the first sensor nor the second sensor is physically failed; A current output module is used to output a power battery current that meets functional safety requirements based on the first channel current, the second channel current, the physical failure state of the first sensor, the physical failure state of the second sensor, the data failure state of the first sensor, and the data failure state of the second sensor.

[0013] The present application also provides a vehicle, comprising the above-mentioned power battery current detection device.

[0014] The beneficial effects of the present invention are: The above current acquisition processing and diagnosis process effectively prevents excessive current usage despite limited current capabilities, directly avoiding subsequent irreversible risks. Accurate current determination and processing also improves fault accuracy, effectively avoiding false positives and missed positives, and enhances software control precision. It also addresses misdiagnosis and battery safety issues caused by current acquisition anomalies and errors. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1This is a flow chart of a method for detecting current of a power battery in an embodiment of the application; Figure 2 Schematic diagram of current output logic for various working conditions related to step S104 in the application embodiment. DETAILED DESCRIPTION

[0016] To facilitate understanding by those skilled in the art, the present invention is further described below with reference to the accompanying drawings. The detailed description is complete, but it should not be construed as limiting the scope of the present invention. Obvious variations and alternative forms of the following examples are all within the scope of protection of this patent.

[0017] Reference Figure 1 The present application provides a method for detecting current in a power battery. A first current sensor and a second current sensor having different acquisition accuracy are arranged in a high-voltage circuit of the power battery. The method for detecting current in the power battery includes: S101, obtaining a first channel current and a second channel current respectively collected by the first sensor and the second sensor; S102, obtaining the physical failure status of the first sensor and the second sensor; S103: When neither the first sensor nor the second sensor is physically failed, determine data failure states of the first sensor and the second sensor according to the first channel current and the second channel current; S104: Output a power battery current that meets functional safety requirements based on the first channel current, the second channel current, the physical failure status of the first sensor, the physical failure status of the second sensor, the data failure status of the first sensor, and the data failure status of the second sensor.

[0018] The current in the high-voltage circuit of the power battery is measured simultaneously by two current sensors with different acquisition accuracy to obtain two independent sets of current data; the two sensors work at the same time, and even if one of the sensors fails, the data of the other sensor can still be used for reference; and sensors with different acquisition accuracy can be verified with each other to improve the overall measurement accuracy.

[0019] In actual applications, after the current sensor is connected to the high-voltage circuit of the power battery, due to its complex working environment (such as high voltage, large current, high temperature, etc.), it is prone to various faults such as sampling line failure, power supply failure, overtemperature failure, etc. When any one or more of these faults occurs, it is determined that the sensor has physically failed.

[0020] In the embodiment of the present application, the acquisition accuracy of the first sensor is higher than that of the second sensor.

[0021] For example, a fluxgate current sensor is used as the first sensor to collect the current value currently flowing through the battery pack in real time as the first channel current; for example, a shunt current sensor is used as the second current sensor to collect the current value currently flowing through the battery pack in real time as the second channel current.

[0022] In the embodiment of the present application, when neither the first sensor nor the second sensor is physically failed, step S103 of determining the data failure status of the first sensor and the second sensor according to the first channel current and the second channel current includes: S1031, determining a maximum error difference between the first sensor and the second sensor based on a preset acquisition error range of the first sensor and a preset acquisition error range of the second sensor; S1032, determining a current difference between the first channel current and the second channel current; S1033: If the current difference exceeds the maximum error difference, determine that the data of the first sensor and the second sensor are invalid; otherwise, determine that the data of the first sensor and the second sensor are not invalid.

[0023] The first and second sensors are factory-set with a preset acquisition error range. This range is an inherent characteristic of the sensor and describes the allowable deviation in its measurement accuracy. In the present embodiment, the preset acquisition error range of the first current sensor and the preset acquisition error range of the second current sensor refer to the measurement error ranges set by the manufacturer for these two current sensors at the time of shipment, based on their design and calibration standards.

[0024] The maximum error difference between the first sensor and the second sensor refers to the difference between the minimum value of the preset error range of the first sensor and the maximum value of the preset error range of the second sensor, or the difference between the maximum value of the preset error range of the first sensor and the minimum value of the preset error range of the first sensor; in actual conditions, the specific values ​​of the preset acquisition error ranges of the two sensors are used to determine whether it is the difference between the minimum value of the preset error range of the first sensor and the maximum value of the preset error range of the second sensor, or the difference between the maximum value of the preset error range of the first sensor and the minimum value of the preset error range of the first sensor.

[0025] For example, it is assumed that the preset acquisition error range of the first current sensor is ±0.05A; and the preset acquisition error range of the second current sensor is ±0.1A.

[0026] The maximum error difference refers to the difference in the errors of the two sensors under the worst-case scenario (i.e., when the errors are in opposite directions). When the error of the first current sensor is +0.05A and the error of the second current sensor is -0.1A, the error difference is: 0.05A - (-0.1A) = 0.05A + 0.1A = 0.15A. When the error of the first current sensor is -0.05A and the error of the second current sensor is +0.1A, the error difference is: -0.05A - 0.1A = -0.15A.

[0027] The maximum error difference is the one with the larger absolute value in the above two cases, that is: max(|0.15 A ∣,∣−0.15 A ∣)=0.15 A Therefore, the maximum error difference between the first current sensor and the second current sensor is 0.15A.

[0028] If the current difference is greater than the maximum error difference, it means that the difference between the measurement results of the two sensors exceeds the range that can be explained by their error ranges. Therefore, it can be determined that the data of the first current sensor and the second current sensor are both invalid.

[0029] Based on the above failure conditions and the charging and discharging direction problem of the current value itself, the embodiment of the present invention decomposes a total of eleven failure scenarios, including channel one failure and channel two normal, channel one normal and channel two failure, channel one failure and channel two failure, channel one normal and channel two normal but data failure, etc.

[0030] For these current failure scenarios, an available current is required to support subsequent overcurrent diagnosis. This paper combines the actual current values ​​collected by the two channels and the failure impact of the current sensor itself to propose current processing methods for these eleven failure scenarios: If the first channel current fails and the second channel is normal, the second channel current value is used; If channel one is normal and channel two fails, the current value of the first channel is used; If channel 1 and channel 2 fail, the last valid value will be used; If channel 1 is normal and channel 2 is normal but data is invalid, the maximum value is used; If channel 1, channel 2, and data are normal, the current value of the first channel is used.

[0031] Based on the above processing principles, all working conditions can be covered and correct and accurate current values ​​can be obtained for subsequent overcurrent diagnosis.

[0032] After processing the above current values, the corresponding charging and discharging currents can be derived. The resulting charging and discharging currents are used for overcurrent diagnosis. When the charging current exceeds the currently allowed charging current by a certain small multiple, it is considered a charging overcurrent, and the charging power should be limited. When the charging current exceeds the currently allowed charging current by a certain large multiple, it is considered a severe charging overcurrent, and the disconnect relay should be immediately controlled to disconnect the charging circuit to prevent continuous charging. When the discharge current exceeds the currently allowed discharge current by a certain small multiple, it is considered a discharge overcurrent, and the discharge power should be limited. When the discharge current exceeds the currently allowed discharge current by a certain large multiple, it is considered a severe discharge overcurrent, and the disconnect relay should be immediately controlled to disconnect the discharge circuit to prevent continuous discharge.

[0033] The above current acquisition processing and diagnosis process effectively prevents excessive current usage despite limited current capabilities, directly avoiding subsequent irreversible risks. Accurate current determination and processing also improves fault accuracy, effectively avoiding false positives and missed positives, and enhances software control precision. It also addresses misdiagnosis and battery safety issues caused by current acquisition anomalies and errors.

[0034] In the embodiment of the present application, step S104 of outputting a power battery current that meets functional safety requirements based on the first channel current, the second channel current, the physical failure state of the first sensor, the physical failure state of the second sensor, the data failure state of the first sensor, and the data failure state of the second sensor includes: S1041: If one of the first sensor and the second sensor fails and the other is valid, output current according to the valid sensor; S1042: If both the first sensor and the second sensor fail, output current according to the effective current output last time; S1043: If both the first sensor and the second sensor are physically valid, data of the first sensor and the second sensor are invalid, and the first channel current and the second channel current are of the same type, output the current according to the larger value of the first channel current and the second channel current; S1044: If the first sensor and the second sensor are both physically valid, data of the first sensor and the second sensor are invalid, and the first channel current and the second channel current are different types of current, outputting currents of corresponding types according to the first channel current and the second channel current; S1045: If the first sensor and the second sensor are both physically valid and the data of the first sensor and the second sensor are not invalid, output the current according to the first channel current.

[0035] If one of the first sensor and the second sensor fails and the other is valid, step S1041 of outputting current according to the valid sensor includes: If the first sensor is not failed, the second sensor is failed, and the first channel current is a charging current, the first channel current is output as the charging current, and the discharge current is set to 0; If the first sensor is not failed, the second sensor is failed, and the first channel current is a discharge current, the first channel current is output as the discharge current, and the charging current is set to 0; If the first sensor physically fails, the second sensor is not failed, and the second channel current is a charging current, the second channel current is output as the charging current, and the discharge current is set to 0; If the first sensor physically fails, the second sensor is not failed, and the second channel current is a discharge current, the second channel current is output as the discharge current, and the charging current is set to 0.

[0036] If both the first sensor and the second sensor are physically valid, data of the first sensor and the second sensor are invalid, and the first channel current and the second channel current are of the same type, step S1042 of outputting current according to the larger value of the first channel current and the second channel current includes: If both the first sensor and the second sensor are physically valid, the data of the first sensor and the second sensor are invalid, and both the first channel current and the second channel current are charging currents, the larger value of the first channel current and the second channel current is output as the charging current, and the discharging current is set to 0; If the first sensor and the second sensor are both physically valid, the data of the first sensor and the second sensor are invalid, and the first channel current and the second channel current are both discharge currents, the discharge current is output according to the larger value of the first channel current and the second channel current, and the charging current is set to 0.

[0037] If the first sensor and the second sensor are both physically valid, data of the first sensor and the second sensor are invalid, and the first channel current and the second channel current are different types of current, step S1044 of outputting currents of corresponding types according to the first channel current and the second channel current includes: If both the first sensor and the second sensor are physically valid, data of the first sensor and the second sensor are invalid, and the first channel current is a charging current and the second channel current is a discharging current, the charging current is output according to the first channel current, and the discharging current is output according to the second channel current; If the first sensor and the second sensor are both physically valid, the data of the first sensor and the second sensor are invalid, and the first channel current is a discharge current and the second channel current is a charge current, the discharge current is output according to the first channel current, and the charging current is output according to the second channel current.

[0038] If the first sensor and the second sensor are both physically valid and the data of the first sensor and the second sensor are not invalid, the step S1045 of outputting the current according to the first channel current includes: The first sensor and the second sensor are both physically valid, data of the first sensor and the second sensor are not invalid, and the first channel current is a charging current. The first channel current is output as the charging current, and the discharge current is set to 0; The first sensor and the second sensor are both physically valid, data of the first sensor and the second sensor are both valid, and the first channel current is a discharge current. The first channel current is output as the discharge current, and the charging current is set to 0.

[0039] Reference Figure 2 In this embodiment, a detailed analysis and description of the dual-channel acquisition failure is made, including the dual-channel failure mode and the data processing logic after failure. The judgment of abnormal situations has a priority, and the priority of the acquisition failure judgment is higher, followed by the data validity failure, and finally the processing of the no-fault state. The order is as follows Figure 2 For S1-S11 in each case, the specific processing steps are as follows: The first case involved in the dual-channel current mentioned above is S1: there is no collection problem for the first channel current, but there is a collection problem for the second channel current. At this time, the first channel current is collected as the charging current, so the charging current directly uses the first channel current, and the discharge current is processed as 0.

[0040] The second case involved in the above dual-channel current is S2: there is no collection problem for the first channel current, but there is a collection problem for the second channel current. At this time, the first channel current is collected as the discharge current, so the discharge current directly uses the first channel current, and the charging current is processed as 0.

[0041] The third situation involved in the above dual-channel current is S3: there is a collection problem with the first channel current, and there is no collection problem with the second channel current. At this time, the second channel current is collected as the charging current, so the charging current directly uses the second channel current, and the discharge current is processed as 0.

[0042] The fourth situation involved in the above dual-channel current is S4: there is a collection problem with the first channel current, and there is no collection problem with the second channel current. At this time, the second channel current is collected as the discharge current, so the discharge current directly uses the second channel current, and the charging current is processed as 0.

[0043] The fifth situation involved in the above-mentioned dual-channel current is S5: there is a collection problem with the current of the first channel, and there is a collection problem with the current of the second channel. At this time, the currents of the two channels are both invalid, and the charging current maintains the effective value of the previous moment, and the discharging current maintains the effective value of the previous moment.

[0044] The sixth case involved in the above-mentioned dual-channel current is S6: there is no collection problem for the first channel current, there is no collection problem for the second channel current, and at this time the first channel current and the second channel current are both charging currents, but the difference between the two channel current values ​​is greater than the maximum error difference between the two sensors. In this case, the charging current uses the maximum charging value of the two channels, and the discharge current is processed as 0.

[0045] The seventh case involved in the above-mentioned dual-channel current is S7: there is no collection problem for the first channel current, there is no collection problem for the second channel current, and at this time the first channel current and the second channel current are both discharge currents, but the difference between the two channel current values ​​is greater than the maximum error difference between the two sensors. In this case, the discharge current uses the maximum discharge value of the two channels, and the charging current is processed as 0.

[0046] The eighth situation involved in the above-mentioned dual-channel current is S8: there is no collection problem for the first channel current, there is no collection problem for the second channel current, and at this time the first channel current is the charging current and the second channel current is the discharging current, but the difference between the two channel current values ​​is greater than the maximum error difference between the two sensors, then the charging current uses the first channel current and the discharging current uses the second channel current.

[0047] The ninth situation involved in the above-mentioned dual-channel current is S9: there is no collection problem for the first channel current, there is no collection problem for the second channel current, and at this time the first channel current is the discharge current and the second channel current is the charging current, but the difference between the two channel current values ​​is greater than the maximum error difference between the two sensors, then the charging current uses the second channel current and the discharging current uses the first channel current.

[0048] The tenth case involved in the above-mentioned dual-channel current is S10: there is no acquisition problem with the first channel current, there is no acquisition problem with the second channel current, and the difference between the two channel current values ​​is within the error range. At this time, the first channel current is the charging current, then the charging current uses the first channel current, and the discharge current is processed as 0.

[0049] The eleventh case involved in the above-mentioned dual-channel current is S11: there is no acquisition problem with the first channel current, there is no acquisition problem with the second channel current, and the difference between the two channel current values ​​is within the error range. At this time, the first channel current is the discharge current, then the discharge current uses the first channel current, and the charging current is processed as 0.

[0050] After obtaining a valid and correct current value based on the output of S104, this current value is used to perform battery overcurrent diagnosis. If the charging current is greater than or equal to the maximum allowable charging current of the battery at a low rate, the battery pack is considered to have a charging overcurrent fault, and the charging overcurrent status needs to be recorded. If the charging current is greater than or equal to the maximum allowable charging current of the battery at a high rate, the battery pack is considered to have a severe charging overcurrent fault, and the charging severe overcurrent status needs to be recorded. If the discharge current is greater than or equal to the maximum allowable discharge current of the battery at a low rate, the battery pack is considered to have a discharge overcurrent fault, and the discharge overcurrent status needs to be recorded. If the discharge current is greater than or equal to the maximum allowable discharge current of the battery at a high rate, the battery pack is considered to have a severe discharge overcurrent fault, and the discharge severe overcurrent status needs to be recorded. Finally, after determining the charge and discharge fault status, the battery system needs to be controlled and limited based on the fault's impact. If both charge and discharge overcurrent faults occur, the battery pack is considered to be in a low fault state, and the allowable charge and discharge current of the battery pack needs to be limited. When a serious overcurrent fault occurs during charging and discharging, the battery pack is considered to be in a high fault state. If it is used again, it is likely to cause subsequent thermal runaway faults. Therefore, the high voltage state of the battery pack needs to be controlled. In order to protect the battery pack, the high voltage state of the battery should be cut off immediately, and high voltage is prohibited again during this key cycle.

[0051] The above method in the embodiment of this application effectively improves the accuracy and reliability of power battery current detection through a dual-channel current detection mechanism combined with multi-level failure detection and data processing logic. The specific technical effects are as follows: By deploying a first current sensor (such as a fluxgate current sensor) and a second current sensor (such as a shunt current sensor) with different acquisition accuracies, the present invention leverages the complementary properties of the two sensors to improve the accuracy and reliability of current measurement. The high precision of the first sensor provides accurate current values, while the second sensor acts as a redundant backup, ensuring reference data is still available in the event of a failure of the first sensor.

[0052] This invention not only detects physical sensor failures (such as sampling line faults, power supply failures, and overtemperature faults), but also determines data failures by comparing the measurement data from two sensors. By calculating the maximum error difference between the two sensors and comparing it with the actual current difference, it accurately determines the validity of the sensor data. This multi-layered failure detection mechanism effectively avoids misjudgments due to sensor failures or data anomalies.

[0053] The embodiments of this invention propose detailed current processing methods for different failure scenarios, ensuring that the power battery current output meets functional safety requirements in all situations. For example, if one sensor fails, the data from the other sensor is used; if both sensors fail, the last valid value is used; and if the data fails but the sensor is physically normal, the appropriate processing strategy is selected based on the current type. This processing logic covers all possible operating conditions, ensuring that the current output meets functional safety requirements.

[0054] Based on accurate current values, the present invention enables effective overcurrent diagnosis. By setting different overcurrent thresholds (small and large rates), it can distinguish between mild and severe overcurrent conditions and take appropriate control measures. For example, it limits the charge or discharge power in the case of mild overcurrent, while immediately disconnecting the high-voltage circuit in the case of severe overcurrent, effectively avoiding battery damage and safety risks caused by overcurrent.

[0055] By carefully analyzing dual-channel failure modes and the corresponding processing logic, the present invention effectively handles various abnormal situations. For example, when the difference between the two channel data exceeds the error range, a reasonable current value is selected for output. In the event of a channel failure, data from the valid channel is prioritized. This fault-tolerance mechanism significantly improves the system's robustness and reliability.

[0056] The present application also provides a power battery current detection device, in which a first current sensor and a second current sensor with different acquisition accuracy are arranged in a high-voltage circuit of the power battery. The power battery current detection device includes: An acquisition module, configured to acquire a first channel current and a second channel current respectively acquired by the first sensor and the second sensor; a failure status module, configured to obtain the physical failure status of the first sensor and the second sensor; a data failure state determining module, configured to determine the data failure state of the first sensor and the second sensor according to the first channel current and the second channel current when neither the first sensor nor the second sensor is physically failed; A current output module is used to output a power battery current that meets functional safety requirements based on the first channel current, the second channel current, the physical failure state of the first sensor, the physical failure state of the second sensor, the data failure state of the first sensor, and the data failure state of the second sensor.

[0057] An embodiment of the present application further provides a vehicle, comprising the power battery current detection device as described in the above claims.

[0058] It should be noted that the various embodiments in this specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same and similar parts between the various embodiments can be referenced to each other.

[0059] Although the preferred embodiments of the present invention have been described, those skilled in the art may make additional changes and modifications to these embodiments once they become aware of the basic creative concepts. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications that fall within the scope of the embodiments of the present invention.

[0060] It should also be noted that, in this document, the terms "center", "up", "down", "left", "right", "vertical", "horizontal", "inside", "outside" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, and are for the purpose of facilitating the description of the present invention and simplifying the description, rather than indicating or implying that the devices or components referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the present invention. In addition, relational terms such as "first" and "second" are used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply that there is any actual relationship or order between these entities or operations, nor should they be understood as indicating or implying relative importance. Moreover, the terms "comprises", "includes" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or terminal device comprising a series of elements does not include those elements, but also includes other elements not explicitly listed, or also includes elements inherent to such process, method, article or terminal device. In the absence of further restrictions, an element defined by the sentence "comprising a ..." does not exclude the presence of other identical elements in the process, method, article or terminal device comprising the element.

[0061] The technical solutions provided by the present invention have been described in detail above. Specific examples are used herein to illustrate the principles and implementation methods of the present invention. The description of the above embodiments is intended only to facilitate understanding of the present invention, and the contents of this specification should not be construed as limiting the present invention. Furthermore, those skilled in the art will appreciate that various modifications may be made to the specific implementation methods and scope of application according to the present invention. It is not necessary and impossible to exhaustively enumerate all implementation methods herein, and any obvious variations or modifications derived therefrom remain within the scope of protection of the present invention.

Claims

1. A power battery current detection method, characterized in that: A first current sensor and a second current sensor with different acquisition accuracy are arranged in a high-voltage circuit of a power battery. The power battery current detection method includes: Acquire a first channel current and a second channel current respectively collected by the first sensor and the second sensor; Acquiring a physical failure status of the first sensor and the second sensor; When neither the first sensor nor the second sensor is physically failed, determining data failure states of the first sensor and the second sensor according to the first channel current and the second channel current; Output a power battery current that meets functional safety requirements based on the first channel current, the second channel current, the physical failure state of the first sensor, the physical failure state of the second sensor, the data failure state of the first sensor, and the data failure state of the second sensor.

2. The power battery current detection method according to claim 1, characterized in that: The acquisition accuracy of the first sensor is higher than that of the second sensor.

3. The power battery current detection method according to claim 1, characterized in that: When neither the first sensor nor the second sensor is physically failed, the step of determining the data failure status of the first sensor and the second sensor according to the first channel current and the second channel current includes: determining a maximum error difference between the first sensor and the second sensor according to a preset acquisition error range of the first sensor and a preset acquisition error range of the second sensor; determining a current difference between the first channel current and the second channel current; If the current difference exceeds the maximum error difference, it is determined that the data of the first sensor and the second sensor are invalid; otherwise, it is determined that the data of the first sensor and the second sensor are not invalid.

4. The power battery current detection method according to claim 2, characterized in that: The step of outputting a power battery current that meets functional safety requirements according to the first channel current, the second channel current, the physical failure state of the first sensor, the physical failure state of the second sensor, the data failure state of the first sensor, and the data failure state of the second sensor includes: If one of the first sensor and the second sensor is physically invalid and the other is physically valid, the current output is performed according to the physically valid sensor; If both the first sensor and the second sensor are physically failed, the current output is performed according to the effective current output last time; If both the first sensor and the second sensor are physically valid, data of the first sensor and the second sensor are invalid, and the first channel current and the second channel current are of the same type, outputting the current according to the larger value of the first channel current and the second channel current; If the first sensor and the second sensor are both physically valid, data of the first sensor and the second sensor are invalid, and the first channel current and the second channel current are different types of current, outputting current of corresponding types according to the first channel current and the second channel current; If the first sensor and the second sensor are both physically valid and the data of the first sensor and the second sensor are not invalid, the current is output according to the first channel current.

5. The power battery current detection method according to claim 4, characterized in that: If one of the first sensor and the second sensor is physically invalid and the other is physically valid, the step of outputting current according to the physically valid sensor includes: If the first sensor is not physically failed, the second sensor is physically failed, and the first channel current is a charging current, the first channel current is output as the charging current, and the discharge current is set to 0; If the first sensor is not physically failed, the second sensor is physically failed, and the first channel current is a discharge current, the first channel current is output as the discharge current, and the charging current is set to 0; If the first sensor fails physically, the second sensor does not fail physically, and the second channel current is a charging current, the second channel current is output as the charging current, and the discharge current is set to 0; If the first sensor physically fails, the second sensor does not physically fail, and the second channel current is a discharge current, the second channel current is output as the discharge current, and the charging current is set to 0.

6. The power battery current detection method according to claim 4, characterized in that: If both the first sensor and the second sensor are physically valid, data of the first sensor and the second sensor are invalid, and the first channel current and the second channel current are of the same type, the step of outputting current according to the larger value of the first channel current and the second channel current includes: If both the first sensor and the second sensor are physically valid, the data of the first sensor and the second sensor are invalid, and both the first channel current and the second channel current are charging currents, the larger value of the first channel current and the second channel current is output as the charging current, and the discharging current is set to 0; If the first sensor and the second sensor are both physically valid, the data of the first sensor and the second sensor are invalid, and the first channel current and the second channel current are both discharge currents, the discharge current is output according to the larger value of the first channel current and the second channel current, and the charging current is set to 0.

7. The power battery current detection method according to claim 4, characterized in that: If both the first sensor and the second sensor are physically valid, data of the first sensor and the second sensor are invalid, and the first channel current and the second channel current are different types of current, the step of outputting current of corresponding types according to the first channel current and the second channel current includes: If both the first sensor and the second sensor are physically valid, data of the first sensor and the second sensor are invalid, and the first channel current is a charging current and the second channel current is a discharging current, the charging current is output according to the first channel current, and the discharging current is output according to the second channel current; If the first sensor and the second sensor are both physically valid, the data of the first sensor and the second sensor are invalid, and the first channel current is a discharge current and the second channel current is a charge current, the discharge current is output according to the first channel current, and the charging current is output according to the second channel current.

8. The power battery current detection method according to claim 4, characterized in that: If both the first sensor and the second sensor are physically valid and data of both the first sensor and the second sensor are valid, the step of outputting current according to the first channel current includes: The first sensor and the second sensor are both physically valid, data of the first sensor and the second sensor are not invalid, and the first channel current is a charging current. The first channel current is output as the charging current, and the discharge current is set to 0; The first sensor and the second sensor are both physically valid, data of the first sensor and the second sensor are both valid, and the first channel current is a discharge current. The first channel current is output as the discharge current, and the charging current is set to 0.

9. A power battery current detection device, characterized in that: A first current sensor and a second current sensor with different acquisition accuracy are arranged in the high-voltage circuit of the power battery. The power battery current detection device includes: An acquisition module, configured to acquire a first channel current and a second channel current respectively acquired by the first sensor and the second sensor; a failure status module, configured to obtain the physical failure status of the first sensor and the second sensor; a data failure state determining module, configured to determine the data failure state of the first sensor and the second sensor according to the first channel current and the second channel current when neither the first sensor nor the second sensor is physically failed; A current output module is used to output a power battery current that meets functional safety requirements based on the first channel current, the second channel current, the physical failure state of the first sensor, the physical failure state of the second sensor, the data failure state of the first sensor, and the data failure state of the second sensor.

10. A vehicle, characterized in that: Including the power battery current detection device as described in claim 9.

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