Overcurrent fault recognition method, motor drive unit and computer readable storage medium

Abstract

The application discloses an overcurrent fault identification method, a motor driving unit and a storage medium. The method comprises the following steps: when an overcurrent fault signal is detected, determining a triggering time of the overcurrent fault signal; obtaining three-phase current values in a sampling period in which the triggering time is located; and determining a fault type according to a comparison result of a sum value of the three-phase current values and a first threshold value and a comparison result of each-phase current value and a second threshold value. In the case that the overcurrent fault identification method detects the overcurrent fault signal and determines that a hardware overcurrent fault occurs, in order to determine the specific fault type of the hardware overcurrent fault, three-phase current values of a driving motor in a sampling period in which the triggering time of the overcurrent fault signal is located are obtained, the change characteristics of the three-phase current values when the hardware overcurrent fault occurs are known, and then the fault type of the hardware overcurrent fault is determined according to the three-phase current values, so that the fault reason of the hardware overcurrent fault is known.

Description

Technical Field

[0001] This invention relates to the field of fault detection technology, and in particular to an overcurrent fault identification method, a motor drive unit, and a computer-readable storage medium. Background Technology

[0002] As the power unit of new energy vehicles, the electric drive system's fault diagnosis capability is of great significance for fault location during vehicle application, vehicle repair methods after a fault, electric drive system design, and production quality improvement.

[0003] Hardware overcurrent faults are common in electric drive systems, and the causes are diverse. Currently, existing technologies can only determine whether a hardware overcurrent fault has occurred in the electric drive system, but cannot accurately identify the specific type of fault. This leads to reduced maintenance efficiency due to the unclear cause of the overcurrent fault in the entire vehicle.

[0004] The above content is only used to help understand the technical solution of the present invention and does not represent an admission that the above content is related technology. Summary of the Invention

[0005] The main objective of this invention is to provide an overcurrent fault identification method, a motor drive unit, and a computer-readable storage medium, aiming to solve the problem that the maintenance efficiency of a vehicle is reduced due to the unknown cause of overcurrent faults during the maintenance process.

[0006] To achieve the above objectives, the present invention provides an overcurrent fault identification method, the overcurrent fault identification method comprising:

[0007] When an overcurrent fault signal is detected, the triggering time of the overcurrent fault signal is determined;

[0008] The three-phase current values ​​are obtained during the sampling period at the trigger time, and the three-phase current values ​​represent the instantaneous current when the drive motor is running;

[0009] The fault type that triggers the overcurrent fault signal is determined based on the comparison between the sum of the three-phase current values ​​and the first threshold, and the comparison between the current values ​​of each phase and the second threshold.

[0010] Optionally, the first threshold includes an upper limit of the sum of the three-phase current zero drift, and the second threshold includes: an upper limit of the current zero drift and a hardware overcurrent fault threshold.

[0011] Accordingly, the step of determining the fault type that triggers the overcurrent fault signal based on the comparison result of the sum of the three-phase current values ​​with the first threshold and the comparison result of each phase current value with the second threshold includes:

[0012] Compare the sum of the three-phase current values ​​with the upper limit of the sum of the three-phase current zero drift values;

[0013] When the sum of the three-phase current values ​​is less than or equal to the upper limit of the sum of the three-phase current zero drift, the fault type that triggers the overcurrent fault signal is determined based on the comparison result between the current values ​​of each phase and the corresponding upper limit of the current zero drift.

[0014] When the sum of the three-phase current values ​​is greater than the upper limit of the sum of the three-phase current zero drift, the fault type that triggers the overcurrent fault signal is determined based on the comparison result between the current values ​​of each phase and the hardware overcurrent fault threshold.

[0015] Optionally, the step of determining the fault type that triggers the overcurrent fault signal based on the comparison result between the current values ​​of each phase and the corresponding upper limit of the current zero drift includes:

[0016] If any one of the phase current values ​​is less than the corresponding current zero drift upper limit, the fault type is determined to be a hardware overcurrent fault caused by a motor phase loss fault.

[0017] When the current values ​​of each phase are all greater than or equal to the corresponding upper limit of current zero drift, the fault type is determined to be a hardware overcurrent fault caused by software control.

[0018] Optionally, the step of determining the fault type that triggers the overcurrent fault signal based on the comparison result between the phase current values ​​and the hardware overcurrent fault threshold includes:

[0019] If any one of the phase current values ​​is greater than the hardware overcurrent fault threshold, the fault type is determined to be a hardware overcurrent fault caused by a single-phase current detection circuit fault.

[0020] When the current values ​​of each phase are all less than or equal to the hardware overcurrent fault threshold, the fault type is determined to be a hardware overcurrent fault caused by the motor phase-to-phase short circuit fault.

[0021] Optionally, the step of obtaining the three-phase current value of the drive motor during the sampling period in which the triggering time occurs includes:

[0022] Obtain the first three-phase current values ​​of the drive motor corresponding to at least two consecutive sampling periods before the triggering time;

[0023] Obtain the second and third phase current values ​​of the drive motor corresponding to at least two consecutive sampling periods after the triggering time;

[0024] Based on the first three-phase current value and the second three-phase current value, the three-phase current value within the sampling period is determined.

[0025] Optionally, after determining the fault type that triggers the overcurrent fault signal based on the sum of the three-phase current values ​​and the current values ​​of each phase, the method further includes:

[0026] Obtain the fault solution corresponding to the fault type;

[0027] Output the fault type and the fault solution.

[0028] Optionally, the step of obtaining a fault solution corresponding to the fault type includes:

[0029] Obtain the solution corresponding to the fault type;

[0030] When there are at least two solutions, a reference fault condition parameter is obtained for each solution. The reference fault condition parameter includes at least one of the following: drive motor model, vehicle model, version number, and three-phase current value.

[0031] Obtain the fault condition parameters corresponding to the time when the overcurrent fault signal is generated;

[0032] The target solution is determined based on the matching rate between the reference fault condition parameters and the fault condition parameters.

[0033] Based on the target solution, determine or generate the fault solution corresponding to the fault type.

[0034] Optionally, the step of determining the target solution based on the matching rate between the reference fault condition parameters and the fault condition parameters includes:

[0035] Obtain the matching rate between the reference fault condition parameters and the fault condition parameters, sort at least two solutions in descending order of the matching rate, and determine the target solution based on the sorted at least two solutions; or,

[0036] Obtain the matching rate between the reference fault condition parameter and the fault condition parameter. When the matching rate is greater than or equal to a preset matching rate, determine the solution corresponding to the reference fault condition parameter as the target solution.

[0037] In addition, to achieve the above objectives, the present invention also provides a motor drive unit, the motor drive unit including a memory, a processor, and a signal decoding program stored in the memory and executable on the processor, wherein when the signal decoding program is executed by the processor, it implements the steps of the overcurrent fault identification method as described above.

[0038] In addition, to achieve the above objectives, the present invention also provides a computer-readable storage medium storing an overcurrent fault identification program, which, when executed by the processor, implements the various steps of the overcurrent fault identification method described above.

[0039] The overcurrent fault identification method, motor drive unit, and computer-readable storage medium proposed in this invention, when an overcurrent fault signal is detected and a hardware overcurrent fault is determined, further determine the specific fault type by acquiring the three-phase current values ​​of the drive motor during the sampling period when the overcurrent fault signal is triggered. This reveals the variation characteristics of the three-phase current values ​​when a hardware overcurrent fault occurs, and the fault type is determined based on the three-phase current values, thus identifying the cause of the hardware overcurrent fault. Therefore, during the maintenance process, knowing the specific fault type of the hardware overcurrent fault allows for a clear understanding of the corresponding fault cause, improving the overall vehicle maintenance efficiency. Attached Figure Description

[0040] Figure 1 This is a schematic diagram of the structure of the overcurrent fault identification device involved in various embodiments of the overcurrent fault identification method of the present invention;

[0041] Figure 2 This is a flowchart illustrating the first embodiment of the overcurrent fault identification method of the present invention;

[0042] Figure 3 For overcurrent diagnostic circuits in electric drive systems;

[0043] Figure 4 The cause of the overcurrent fault in the electric drive system hardware;

[0044] Figure 5 This is a flowchart illustrating the process of determining the fault type in the first embodiment of the overcurrent fault identification method of the present invention;

[0045] Figure 6 This is a flowchart illustrating the second embodiment of the overcurrent fault identification method of the present invention.

[0046] The realization of the objective, functional features and advantages of the present invention will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0047] It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

[0048] In the following description, the use of suffixes such as "module," "part," or "unit" to denote elements is solely for the purpose of illustrative purposes and has no specific meaning in itself. Therefore, "module," "part," or "unit" may be used interchangeably.

[0049] Please refer to Figure 1 , Figure 1 This is a schematic diagram of the structure of the overcurrent fault identification device involved in various embodiments of the overcurrent fault identification method of the present invention.

[0050] like Figure 1 As shown, the overcurrent fault identification device may include a memory 101 and a processor 102. Those skilled in the art will understand that... Figure 1 The structural block diagram of the terminal shown does not constitute a limitation on the terminal. The terminal may include more or fewer components than shown, or combine certain components, or have different component arrangements. The memory 101 stores the operating system and the overcurrent fault identification program. The processor 102 is the control center of the overcurrent fault identification device. The processor 102 executes the overcurrent fault identification program stored in the memory 101 to implement the steps of the various embodiments of the overcurrent fault identification method of the present invention.

[0051] Optionally, the overcurrent fault identification device may also include a display unit 103, which includes a display panel. The display panel may be configured in the form of a liquid crystal display (LCD), an organic light-emitting diode (OLED), or the like, for outputting and displaying the user's browsing interface.

[0052] Optionally, the overcurrent fault identification device also includes a communication unit 104, which establishes data communication with the terminal device through a network protocol (the data communication can be IP communication or Bluetooth channel) to realize data transmission with the terminal device, such as sending the fault type that triggers the overcurrent fault signal and / or the fault solution corresponding to the fault type to the terminal device.

[0053] Based on the above structural block diagram of the overcurrent fault identification device, various embodiments of the overcurrent fault identification method of the present invention are proposed.

[0054] In the first embodiment, the present invention provides an overcurrent fault identification method, please refer to... Figure 2 , Figure 2 This is a schematic flowchart of a first embodiment of the overcurrent fault identification method of the present invention. In this embodiment, the overcurrent fault identification method includes the following steps:

[0055] Step S10: When an overcurrent fault signal is detected, determine the trigger time of the overcurrent fault signal;

[0056] When an overcurrent fault signal is detected, it indicates that a hardware overcurrent fault has occurred. The trigger time of the overcurrent fault signal can be determined by recording the trigger time point when the overcurrent fault signal is generated using a timing device or timing apparatus.

[0057] Optionally, the timing device or timing apparatus may employ at least one of a clock and a timer.

[0058] Optionally, before the step of detecting the overcurrent fault signal, the method further includes:

[0059] Obtain the current three-phase current value of the drive motor;

[0060] The overcurrent fault signal is triggered when one of the three phase current values ​​exceeds the hardware overcurrent fault threshold.

[0061] In practical applications, please refer to Figure 3 , Figure 3 This is a hardware overcurrent diagnostic circuit for the electric drive system (motor drive unit). The circuit includes a current sensor, a current detection circuit, a hardware comparison circuit, and a digital signal processor (DSP). The current sensor samples the three-phase output current (U / V / W) of the drive motor and sends the signals to the three-phase current detection circuit. The processed signals are then sent to the DSP's ADC sampling module for data sampling and simultaneously compared with a preset hardware overcurrent fault threshold by the hardware overcurrent comparison circuit. The output signal from the hardware comparison circuit is sent to the DSP's capture interrupt input pin, triggering a capture interrupt to diagnose the hardware overcurrent fault. Finally, the electric drive system determines that a hardware overcurrent fault has occurred.

[0062] Optionally, the current sensor may be a HALL sensor.

[0063] To obtain the current three-phase current value of the drive motor, the three-phase output current of the drive motor (U / V / W) can be sampled by the HALL sensor to obtain the three-phase current values, namely U-phase current value: I(U), V-phase current value: I(V), and W-phase current value: I(W). When any one of the current phases exceeds the hardware overcurrent fault threshold, that is, when I(U) exceeds the preset hardware overcurrent fault threshold, or when I(V) exceeds the preset hardware overcurrent fault threshold and I(W) exceeds the preset hardware overcurrent fault threshold, an overcurrent fault signal is triggered.

[0064] Optionally, the current three-phase current value of the drive motor can be obtained in real time, or through a preset time period or a preset time interval; there is no limitation on this.

[0065] Step S20: Obtain the three-phase current value within the sampling period at the trigger time, wherein the three-phase current value represents the instantaneous current during the operation of the drive motor;

[0066] Step S30: Determine the fault type that triggers the overcurrent fault signal based on the comparison result of the sum of the three-phase current values ​​with the first threshold and the comparison result of each phase current value with the second threshold.

[0067] The fault types can include: hardware overcurrent faults caused by motor phase loss, hardware overcurrent faults caused by software control, hardware overcurrent faults caused by single-phase current detection circuit faults, and hardware overcurrent faults caused by motor phase-to-phase short circuit faults. It should be noted that the drive motor is controlled by the motor controller, specifically by the control components within the motor controller, which control the changes in the three-phase current. When a control component in the motor controller malfunctions, the three-phase current values ​​will continuously increase. This continuous increase in the three-phase current values ​​can be understood as a hardware overcurrent fault caused by software control.

[0068] The sampling period in which the trigger time is located can be preset. In practical applications, there may be time delay and / or interference when an overcurrent fault signal is detected. By presetting the sampling period in which the overcurrent fault signal trigger time is located, the three-phase current values ​​within the sampling period can be obtained to monitor the variation characteristics of the three-phase current values ​​within the sampling period. Based on the variation of the three-phase current values ​​within the sampling period, the fault type generated by the overcurrent fault signal can be determined.

[0069] The first threshold includes the upper limit of the sum of the three-phase current zero drift, and the second threshold includes the upper limit of the current zero drift and the hardware overcurrent fault threshold.

[0070] Optionally, step S20 includes:

[0071] Obtain the first three-phase current values ​​of the drive motor corresponding to at least two consecutive sampling periods before the triggering time;

[0072] Obtain the second and third phase current values ​​of the drive motor corresponding to at least two consecutive sampling periods after the triggering time;

[0073] Based on the first three-phase current value and the second three-phase current value, the three-phase current value within the sampling period is determined.

[0074] In practical applications, hardware overcurrent faults occur rapidly, with the duration on the order of microseconds. To determine and capture the changes in the three-phase current values ​​when a hardware overcurrent fault occurs, a continuous sampling method is used to obtain the three-phase current values ​​during the sampling period at the trigger time of the hardware overcurrent fault, so as to know the changes in the three-phase current values.

[0075] The sampling period in which the trigger moment occurs includes at least two consecutive sampling periods before the trigger moment and at least two consecutive sampling periods after the trigger moment. Therefore, the three-phase current values ​​within the sampling period can be determined based on the first three-phase current values ​​corresponding to the at least two consecutive sampling periods before the trigger moment, and the second three-phase current values ​​corresponding to the at least two consecutive sampling periods after the trigger moment.

[0076] Optionally, the sampling period in which the trigger time occurs includes 15 consecutive sampling periods before the trigger time and 10 consecutive sampling periods after the trigger time.

[0077] Understandably, one sampling period can determine a set of three-phase current values.

[0078] Optionally, the sampling period in which the trigger time occurs can be determined based on the storage space of the DSP storing the three-phase current values ​​acquired during the sampling period.

[0079] It should be noted that, please refer to Figure 4 , Figure 4 The causes of hardware overcurrent faults in electric drive systems are mainly due to faults in the electric drive system or the drive motor. Electric drive system faults include current detection circuit malfunctions or software control issues causing a continuous increase in current, triggering an overcurrent fault signal. Drive motor faults include phase-to-phase short circuits or phase loss faults.

[0080] It should be noted that when a hardware overcurrent fault occurs, the three-phase current values ​​(U / V / W) will exhibit different characteristics. Furthermore, the triggering of hardware overcurrent interrupts by the three-phase currents (U / V / W) will also differ. Based on this, by analyzing the DSP's ADC current sampling values ​​(current values ​​of each phase) and the sum of the three-phase current values ​​when a hardware overcurrent fault occurs, the specific cause of the hardware overcurrent fault can be distinguished. See the table below for details:

[0081]

[0082] Among them, the hardware overcurrent point includes the upper limit of the current zero drift of the phase corresponding to the three-phase current value and the hardware overcurrent fault threshold.

[0083] As one possible implementation, please refer to... Figure 5 , Figure 5 This is a flowchart illustrating the process of determining the fault type in the first embodiment of the overcurrent fault identification method of the present invention. Step S30 includes:

[0084] Step S31: Compare the sum of the three-phase current values ​​with the upper limit of the sum of the three-phase current zero drift values;

[0085] Step S32: When the sum of the three-phase current values ​​is less than or equal to the upper limit of the sum of the three-phase current zero drift, determine the fault type that triggers the overcurrent fault signal based on the comparison result between the current values ​​of each phase and the corresponding upper limit of the current zero drift.

[0086] Step S33: When the sum of the three-phase current values ​​is greater than the upper limit of the sum of the three-phase current zero drift, the fault type that triggers the overcurrent fault signal is determined based on the comparison result between the current values ​​of each phase and the hardware overcurrent fault threshold.

[0087] Assume the three-phase current values ​​sampled by the ADC are Iu, Iv, and Iw, respectively. Iu_bias, Iv_bias, and Iw_bias are the upper limits of zero drift for each phase of the three-phase current (U / V / W), respectively, and Ioc is the hardware overcurrent fault threshold. It should be noted that the three-phase current values ​​are obtained continuously over multiple sampling periods within the sampling time period where the overcurrent fault signal is triggered, and each sampling period corresponds to one sampling point and one set of three-phase current values.

[0088] In this embodiment, the sum of the three-phase current values ​​in all sampling periods can be compared with the upper limit of the sum of the three-phase current zero drift values ​​to determine whether the sum of the three-phase current values ​​is zero. When the sum of the three-phase current values ​​in all sampling periods is less than or equal to the upper limit, it indicates that the sum of the three-phase current values ​​is zero, and the fault type that triggers the overcurrent fault signal is determined to be a hardware overcurrent fault caused by a motor phase loss fault or a hardware overcurrent fault caused by software control. When the sum of the three-phase current values ​​in all sampling periods is greater than the upper limit, it indicates that the sum of the three-phase current values ​​is not zero, and the fault type that triggers the overcurrent fault signal is determined to be a hardware overcurrent fault caused by a single-phase current detection circuit fault or a hardware overcurrent fault caused by a motor phase-to-phase short circuit fault.

[0089] To further determine the specific fault type of the hardware overcurrent fault, optionally, the step of determining the fault type that triggers the overcurrent fault signal based on the comparison result of the current values ​​of each phase with the corresponding upper limit of current zero drift includes:

[0090] If any one of the phase current values ​​is less than the corresponding current zero drift upper limit, the fault type is determined to be a hardware overcurrent fault caused by a motor phase loss fault.

[0091] When the current values ​​of each phase are all greater than or equal to the corresponding current zero drift upper limit, the fault type is determined to be a hardware overcurrent fault caused by software control.

[0092] In this embodiment, by determining whether there is an absolute value of the phase current in I(U), I(V), and I(W) that is always less than the upper limit of the current zero drift in multiple consecutive sampling periods, if there is, the hardware overcurrent fault type code is assigned to 3, which can be judged as a hardware overcurrent fault caused by motor phase loss; otherwise, the hardware overcurrent fault type code is assigned to 4, which can be judged as a hardware overcurrent fault caused by software control.

[0093] Optionally, the step of determining the fault type that triggers the overcurrent fault signal based on the comparison result between the current values ​​of each phase and the hardware overcurrent fault threshold includes:

[0094] If any one of the phase current values ​​is greater than the hardware overcurrent fault threshold, the fault type is determined to be a hardware overcurrent fault caused by a single-phase current detection circuit fault.

[0095] When the current values ​​of each phase are all less than or equal to the hardware overcurrent fault threshold, the fault type is determined to be a hardware overcurrent fault caused by the inter-phase short circuit fault of the motor.

[0096] If any phase current value exceeds the hardware overcurrent fault threshold, it indicates that at least one of the absolute values ​​of I(U), I(V), and I(W) is greater than the hardware overcurrent fault threshold. The hardware overcurrent fault type code is then assigned a value of 1, indicating a hardware overcurrent fault caused by a fault in the current detection circuit. Otherwise, the hardware overcurrent fault type code is assigned a value of 2, indicating a hardware overcurrent fault caused by a short circuit between motor phases.

[0097] Optionally, determining the fault type that triggers the overcurrent fault signal can be done by first determining the fault type code that triggers the overcurrent fault signal, and then determining the fault type based on the fault type code. Determining the fault type by setting the fault type code can shorten the number of characters outputting the fault type.

[0098] For example, the correspondence between fault type codes and fault types can be preset. When the fault type that triggers the overcurrent fault signal is a hardware overcurrent fault caused by a fault in the current detection circuit, the fault type code is set to 1. When the fault type that triggers the overcurrent fault signal is a hardware overcurrent fault caused by a phase-to-phase short circuit in the motor, the fault type code is set to 2. When the fault type that triggers the overcurrent fault signal is a hardware overcurrent fault caused by a phase loss in the motor, the fault type code is set to 3. When the fault type that triggers the overcurrent fault signal is a hardware overcurrent fault caused by software control, the fault type code is set to 4.

[0099] In the technical solution disclosed in this embodiment, when an overcurrent fault signal is detected and a hardware overcurrent fault is determined, in order to further determine the specific fault type of the hardware overcurrent fault, the three-phase current value of the drive motor during the sampling period when the overcurrent fault signal is triggered is obtained. The change characteristics of the three-phase current value during the sampling period when the hardware overcurrent fault is triggered are known, and then the fault type of the hardware overcurrent fault is determined based on the three-phase current value, so as to know the cause of the hardware overcurrent fault. Thus, during the maintenance process, since the specific fault type of the hardware overcurrent fault is known, the fault cause corresponding to the fault type can be clearly known, thereby improving the maintenance efficiency of the whole vehicle.

[0100] In the second embodiment proposed based on the first embodiment, please refer to Figure 6 , Figure 6 This is a schematic flowchart of a second embodiment of the overcurrent fault identification method of the present invention. In this embodiment, after step S30, the method further includes:

[0101] Step S40: Obtain the fault solution corresponding to the fault type;

[0102] Step S50: Output the fault type and the fault solution.

[0103] It is understandable that different fault types correspond to different fault solutions. A fault solution can include one or at least two methods to resolve the fault. In this embodiment, fault types include, but are not limited to, hardware overcurrent faults caused by motor phase loss, hardware overcurrent faults caused by software control, hardware overcurrent faults caused by single-phase current detection circuit faults, and hardware overcurrent faults caused by motor phase-to-phase short circuit faults. Fault solutions corresponding to each fault type can be preset.

[0104] It should be noted that when the fault type is a hardware overcurrent fault caused by a motor phase loss, the corresponding solutions include, but are not limited to, checking whether the power line connection between the drive motor and the electric drive system is reliable, and replacing the drive motor. For example, checking whether the power line connection between the drive motor and the electric drive system is reliable can specifically involve checking whether the fixing screws of the wiring harness are loose. If the fixing screws are loose, the power wiring harness can be re-twisted; if the fixing screws are not loose, the drive motor can be replaced.

[0105] When the fault type is a hardware overcurrent fault caused by software control, the corresponding fault solutions include, but are not limited to, removing the faulty electric drive system and replacing it with a new electric drive system.

[0106] When the fault type is a hardware overcurrent fault caused by a single-phase current detection circuit fault, the corresponding fault solutions include, but are not limited to, removing the faulty electric drive system and replacing it with a new electric drive system.

[0107] When the fault type is a hardware overcurrent fault caused by a phase-to-phase short circuit fault in the motor, the corresponding fault solutions include, but are not limited to, checking whether the external insulation of the three-phase power harness of the drive motor is damaged, and checking whether there is a phase-to-phase short circuit problem in the drive motor.

[0108] After determining the fault type, based on the pre-set mapping relationship between fault types and fault solutions, the fault solution corresponding to the fault type is obtained, and the fault type and fault solution are output. The solution provided by the fault solution is used to resolve the hardware overcurrent fault, which reduces the repair difficulty when the whole vehicle experiences a hardware overcurrent fault and can improve repair efficiency.

[0109] As an optional implementation, step S40 includes:

[0110] Obtain the solution corresponding to the fault type;

[0111] When there are at least two solutions, a reference fault condition parameter is obtained for each solution. The reference fault condition parameter includes at least one of the following: drive motor model, vehicle model, version number, and three-phase current value.

[0112] Obtain the fault condition parameters corresponding to the time when the overcurrent fault signal is generated;

[0113] The target solution is determined based on the matching rate between the reference fault condition parameters and the fault condition parameters.

[0114] Based on the target solution, determine or generate the fault solution corresponding to the fault type.

[0115] It should be noted that even with the same fault type, the solutions to the faults may differ due to variations in the vehicle's hardware environment and / or fault scenario parameters. The hardware environment can be determined by hardware environment parameters, which include, but are not limited to, at least one of the following: drive motor model, vehicle model, and version number. Fault scenario parameters include, but are not limited to, changes or characteristics of three-phase current values, and the three-phase current values ​​themselves. Therefore, the relationships between fault types, corresponding fault solutions, solutions included in the fault solutions, reference fault parameters corresponding to the solutions, and reference fault conditions corresponding to the solutions can be pre-defined.

[0116] For example, when a reference fault condition is clearly defined based on reference fault parameters, the fault can be resolved by adopting the solution corresponding to the reference fault condition or the solution corresponding to the reference fault condition parameters.

[0117] In this embodiment, to further improve maintenance efficiency and quickly determine the target solution that can resolve the fault from the solutions corresponding to the fault type, when at least two solutions are determined to be corresponding to the fault type, reference fault condition parameters are obtained for each solution. These reference fault condition parameters are used to obtain the hardware environment parameters and fault scenario parameters corresponding to the fault occurrence. The fault condition parameters corresponding to the generation of the overcurrent fault signal are also obtained to clarify the fault condition parameters corresponding to the current actual hardware overcurrent fault. Based on the matching rate between the reference fault condition parameters and the fault condition parameters, the target solution is determined. Based on the matching rate between the reference fault condition parameters and the fault condition parameters, a target reference fault condition that is the same as or similar to the fault condition corresponding to the current actual hardware overcurrent fault is determined. Then, the corresponding target solution is determined based on the target reference fault condition. Finally, a fault solution corresponding to the fault type is determined or generated based on the target solution, so that the fault condition corresponding to the current actual hardware overcurrent fault can be quickly resolved by adopting the target solution from the fault solution.

[0118] Optionally, based on the matching rate between the reference fault condition parameters and the fault condition parameters, a target solution is determined. Based on the matching rate between the reference fault condition parameters and the fault condition parameters, a target reference fault condition that is the same as or similar to the fault condition corresponding to the current actual hardware overcurrent fault is determined. Then, a corresponding target solution is determined based on the target reference fault condition. Based on the target solution, a fault solution corresponding to the fault type is determined or generated, so that the fault condition corresponding to the current actual hardware overcurrent fault can be quickly resolved by adopting the target solution in the fault solution. Specifically, based on the matching rate between the reference fault condition parameters and the fault condition parameters, a target reference fault condition that is the same as or similar to the fault condition parameters can be determined. Based on the target reference fault condition parameters, a target reference fault condition can be determined. Based on the target reference fault condition, a corresponding target solution can be determined.

[0119] Optionally, based on the matching rate between the reference fault condition parameter and the fault condition parameter, a target reference fault condition parameter that is the same as or similar to the fault condition parameter is determined. When the matching rate between the reference fault condition parameter and the fault condition parameter is greater than or equal to a preset matching rate, the reference fault condition parameter is determined as the target reference fault condition parameter that is the same as or similar to the fault condition parameter, indicating that the reference fault condition determined by the target reference fault condition parameter is the same as or similar to the current actual fault condition.

[0120] Optionally, the matching rate between reference fault condition parameters and fault condition parameters can be determined by comparing the hardware environment parameters and / or fault scenario parameters between the reference fault condition parameters and fault condition parameters, and based on the comparison results. For example, the matching rate can be determined by comparing the hardware environment parameters and / or fault scenario parameters between the reference fault condition parameters and fault condition parameters respectively, such as comparing the data items (drive motor model, vehicle model, version number, and three-phase current value) between the reference fault condition parameters and fault condition parameters respectively, identifying the same or similar data items in the comparison results, and determining the matching rate between the reference fault condition parameters and fault condition parameters based on the ratio of these data items to the total number of data items.

[0121] For example, the data items that are the same or similar in the comparison results can be the same or similar drive motor models, the same applies to vehicle models and version numbers, or the corresponding phases of the three-phase current values ​​between the reference fault condition parameters and the fault condition parameters are the same or similar. For example, if the three-phase current values ​​of the reference fault condition parameters are I(U1), I(V1) and I(W1), and the three-phase current values ​​of the fault condition parameters are I(U), I(V) and I(W), when the difference between I(U1) and I(U) is less than or equal to a preset difference, it indicates that the U phase of the three-phase current values ​​is the same or similar, and there is a data item that is the same or similar. The same applies to the V phase and W phase of the three-phase current values, which are the same or similar to the U phase. This will not be elaborated further here.

[0122] Among them, the more identical or similar data items in the comparison results, the larger the ratio of data items to total data items, the higher the matching rate between the reference fault condition parameters and the fault condition parameters, and the more similar the reference fault condition is to the current fault condition. Therefore, based on the solution corresponding to the reference fault condition that is similar to the current fault condition, a solution to the current fault can be generated or determined, which can solve the current fault condition more specifically and quickly.

[0123] Understandably, corresponding to the reference fault condition parameters, the fault condition parameters include at least one of the following: drive motor model, vehicle model, version number, and three-phase current value.

[0124] Optionally, the step of determining the target solution based on the matching rate between the reference fault condition parameters and the fault condition parameters includes:

[0125] Obtain the matching rate between the reference fault condition parameters and the fault condition parameters, sort at least two solutions in descending order of the matching rate, and determine the target solution based on the sorted at least two solutions; or,

[0126] Obtain the matching rate between the reference fault condition parameter and the fault condition parameter. When the matching rate is greater than or equal to a preset matching rate, determine the solution corresponding to the reference fault condition parameter as the target solution.

[0127] In one embodiment, based on the matching rate between reference fault condition parameters and fault condition parameters, a target reference fault condition that is the same as or similar to the fault condition corresponding to the current actual hardware overcurrent fault is identified. The higher the matching rate, the closer the identified target reference fault condition is to the current fault condition. The higher the probability of the solution corresponding to the target reference fault condition successfully resolving the current fault condition, the more efficient the fault resolution becomes. Then, at least two solutions are sorted in descending order of matching rate to determine the target solution. A fault solution is determined or generated based on the target solution. When the current fault condition is resolved in the reference fault solution according to the sorted solutions, the fault is resolved in descending order of the success rate of resolving the current fault condition, thereby improving the maintenance efficiency of fault resolution.

[0128] Optionally, at least two solutions are sorted in descending order of matching rate. That is, given a known matching rate between the reference fault condition parameter and the fault condition parameter, the solutions corresponding to the reference fault condition parameter are obtained, and then sorted in descending order of matching rate. For example, the matching rates between reference fault condition parameters A, B, C, and D and the fault condition parameter are 70%, 60%, 95%, and 90%, respectively. The solutions corresponding to reference fault condition parameters A, B, C, and D are Method 1, Method 2, Method 3, and Method 4, respectively. The solutions are then sorted in descending order of matching rate, resulting in the following sorted solutions: Method 3, Method 4, Method 1, and Method 2.

[0129] In one embodiment, based on the matching rate between the reference fault condition parameters and the fault condition parameters, when the matching rate is greater than or equal to a preset matching rate, a target reference fault condition that is the same as or similar to the fault condition corresponding to the current actual hardware overcurrent fault is identified. The solution determined by the fault condition parameters corresponding to the matching rate being greater than or equal to the preset matching rate is taken as the target solution. That is, the solution provided by the target reference fault condition that is the same as or similar to the current fault condition is taken as the target solution. Based on the target solution, a fault solution corresponding to the fault type is determined or generated, so that the fault condition corresponding to the current actual hardware overcurrent fault can be quickly resolved by adopting the target solution in the fault solution.

[0130] In the technical solution disclosed in this embodiment, after determining the specific fault type of the hardware overcurrent fault, a fault solution corresponding to the fault type can be obtained, the fault type and the fault solution can be output, and the hardware overcurrent fault can be resolved by referring to the solution provided by the fault solution. This reduces the repair difficulty when the vehicle experiences a hardware overcurrent fault, and the repair efficiency can be improved by directly referring to the solution corresponding to the fault solution.

[0131] This invention also proposes a motor drive unit, which includes a memory, a processor, and a signal decoding program stored in the memory and executable on the processor. When executed by the processor, the signal decoding program implements the steps of the overcurrent fault identification method described above. The motor drive unit can be understood as a motor controller.

[0132] The present invention also proposes a computer-readable storage medium storing an overcurrent fault identification program, which, when executed by a processor, implements the steps of the overcurrent fault identification method as described in any of the above embodiments.

[0133] The embodiments of the overcurrent fault identification device and computer-readable storage medium provided by the present invention include all the technical features of the embodiments of the above-described overcurrent fault identification method. The extended and explanatory contents of the specification are basically the same as those of the embodiments of the above-described overcurrent fault identification method, and will not be repeated here.

[0134] It should be noted that, in this document, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or system that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or system. Unless otherwise specified, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or system that includes that element.

[0135] The sequence numbers of the above embodiments of the present invention are for descriptive purposes only and do not represent the superiority or inferiority of the embodiments.

[0136] Through the above description of the embodiments, those skilled in the art can clearly understand that the methods of the above embodiments can be implemented by means of software plus necessary general-purpose hardware platforms. Of course, they can also be implemented by hardware, but in many cases the former is a better implementation method. Based on this understanding, the technical solution of the present invention, or the part that contributes to the prior art, can be embodied in the form of a software product. This computer software product is stored in a computer-readable storage medium (such as ROM / RAM, magnetic disk, optical disk) as described above, and includes several instructions to cause a mobile terminal (which may be a mobile phone, computer, server, controlled terminal, or network device, etc.) to execute the methods of each embodiment of the present invention.

[0137] The above are merely preferred embodiments of the present invention and do not limit the scope of the patent. Any equivalent structural or procedural transformations made based on the description and drawings of the present invention, or direct or indirect applications in other related technical fields, are similarly included within the scope of patent protection of the present invention.

Claims

1. A method for identifying overcurrent faults, characterized in that, The overcurrent fault identification method includes: When an overcurrent fault signal is detected, the triggering time of the overcurrent fault signal is determined; The three-phase current values ​​are obtained during the sampling period at the trigger time, and the three-phase current values ​​represent the instantaneous current when the drive motor is running; The fault type that triggers the overcurrent fault signal is determined based on the comparison between the sum of the three-phase current values ​​and the first threshold, and the comparison between the current values ​​of each phase and the second threshold. The first threshold includes the upper limit of the sum of the three-phase current zero drift, and the second threshold includes the upper limit of the current zero drift and the hardware overcurrent fault threshold.

2. The method as described in claim 1, characterized in that, The step of determining the fault type that triggers the overcurrent fault signal based on the comparison result of the sum of the three-phase current values ​​with the first threshold and the comparison result of each phase current value with the second threshold includes: Compare the sum of the three-phase current values ​​with the upper limit of the sum of the three-phase current zero drift values; When the sum of the three-phase current values ​​is less than or equal to the upper limit of the sum of the three-phase current zero drift, the fault type that triggers the overcurrent fault signal is determined based on the comparison result between the current values ​​of each phase and the corresponding upper limit of the current zero drift. When the sum of the three-phase current values ​​is greater than the upper limit of the sum of the three-phase current zero drift, the fault type that triggers the overcurrent fault signal is determined based on the comparison result between the current values ​​of each phase and the hardware overcurrent fault threshold.

3. The method as described in claim 2, characterized in that, The step of determining the fault type that triggers the overcurrent fault signal based on the comparison result between the current values ​​of each phase and the corresponding upper limit of the current zero drift includes: If any one of the phase current values ​​is less than the corresponding current zero drift upper limit, the fault type is determined to be a hardware overcurrent fault caused by a motor phase loss fault. When the current values ​​of each phase are all greater than or equal to the corresponding upper limit of current zero drift, the fault type is determined to be a hardware overcurrent fault caused by software control.

4. The method as described in claim 2, characterized in that, The step of determining the fault type that triggers the overcurrent fault signal based on the comparison result between the current values ​​of each phase and the hardware overcurrent fault threshold includes: If any one of the phase current values ​​is greater than the hardware overcurrent fault threshold, the fault type is determined to be a hardware overcurrent fault caused by a single-phase current detection circuit fault. When the current values ​​of each phase are all less than or equal to the hardware overcurrent fault threshold, the fault type is determined to be a hardware overcurrent fault caused by the motor phase-to-phase short circuit fault.

5. The method as described in claim 1, characterized in that, The step of obtaining the three-phase current value of the drive motor during the sampling period at the trigger time includes: Obtain the first three-phase current values ​​of the drive motor corresponding to at least two consecutive sampling periods before the triggering time; Obtain the second and third phase current values ​​of the drive motor corresponding to at least two consecutive sampling periods after the triggering time; Based on the first three-phase current value and the second three-phase current value, the three-phase current value within the sampling period is determined.

6. The method as described in claim 1, characterized in that, After determining the fault type that triggers the overcurrent fault signal based on the sum of the three-phase current values ​​and the current values ​​of each phase, the method further includes: Obtain the fault solution corresponding to the fault type; Output the fault type and the fault solution.

7. The method as described in claim 6, characterized in that, The steps for obtaining the fault solution corresponding to the fault type include: Obtain the solution corresponding to the fault type; When there are at least two solutions, a reference fault condition parameter is obtained for each solution. The reference fault condition parameter includes at least one of the following: drive motor model, vehicle model, version number, and three-phase current value. Obtain the fault condition parameters corresponding to the time when the overcurrent fault signal is generated; The target solution is determined based on the matching rate between the reference fault condition parameters and the fault condition parameters. Based on the target solution, determine or generate the fault solution corresponding to the fault type.

8. The method as described in claim 7, characterized in that, The step of determining the target solution based on the matching rate between the reference fault condition parameters and the fault condition parameters includes: Obtain the matching rate between the reference fault condition parameters and the fault condition parameters, sort at least two solutions in descending order of the matching rate, and determine the target solution based on the sorted at least two solutions; or, Obtain the matching rate between the reference fault condition parameter and the fault condition parameter. When the matching rate is greater than or equal to a preset matching rate, determine the solution corresponding to the reference fault condition parameter as the target solution.

9. A motor drive unit, characterized in that, The motor drive unit includes a memory, a processor, and a signal decoding program stored in the memory and executable on the processor. When the signal decoding program is executed by the processor, it implements the steps of the overcurrent fault identification method as described in any one of claims 1-8.

10. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores a signal decoding program, which, when executed by a processor, implements the steps of the overcurrent fault identification method as described in any one of claims 1-8.

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