Method and device for determining stall of driving motor in vehicle, and vehicle-mounted terminal

Abstract

The application discloses a method and device for determining the stall of a driving motor in a vehicle and a vehicle-mounted terminal, and relates to the technical field of vehicle detection. The method comprises the following steps: obtaining the rotation speed and driving current of the driving motor in the vehicle during the driving of the vehicle; when the rotation speed is less than a preset stall rotation speed threshold, determining the heat accumulation value corresponding to the driving motor based on the driving current of the driving motor and a preset stall current threshold; and determining whether the driving motor stalls during the driving of the vehicle based on the heat accumulation value and a preset stall heat accumulation value, wherein the preset stall heat accumulation value is used to represent the maximum heat value accumulated by the driving motor from the normal driving of the vehicle to the stall process. The embodiments provided in the application can accurately determine the stall of the driving motor under different output torques, improve the accuracy and efficiency of stall identification, and thus prolong the service life of the driving motor.

Description

Technical Field

[0001] This application relates to the field of vehicle detection technology, and in particular to a method, device and vehicle terminal for determining the stall of a drive motor in a vehicle. Background Technology

[0002] Currently, with social development and technological progress, the market share of electric vehicles is increasing. As the most core power component of electric vehicles, the safety and reliability of the drive motor assembly have received increasing attention. The performance of the drive motor in driving the vehicle uphill is an important indicator of a car. Due to the presence of a battery pack in electric vehicles, their weight is heavier than that of ordinary fuel vehicles. Therefore, climbing hills is a test for the drive motor-driven powertrain. During the process of climbing hills, the vehicle is very prone to hill-hanging, which can lead to the drive motor stalling. This stalling condition can easily damage the drive motor.

[0003] However, traditional methods for determining drive motor stall are usually based on the time it takes for the drive motor to stall under different output torques. But this method can only be used when the output torque is constant. It cannot determine the stall status of the drive motor under different output torques, which leads to low accuracy in stall identification. Furthermore, since the transmission path for different output torques is relatively long, the drive motor may be damaged during signal transmission, resulting in low efficiency in stall identification and affecting the lifespan of the drive motor. Summary of the Invention

[0004] This application provides a method, device, and vehicle terminal for determining the stall condition of a drive motor in a vehicle. The embodiments provided by this application solve the technical problems of low accuracy and low efficiency in stall identification in the prior art. The embodiments provided by this application can accurately determine the stall condition of the drive motor under different output torques, improve the accuracy and efficiency of stall identification, and thus extend the service life of the drive motor.

[0005] In a first aspect, this application provides a method for determining the stall of a drive motor in a vehicle, the method comprising:

[0006] During vehicle operation, the rotational speed and drive current of the drive motor in the vehicle are acquired;

[0007] When the rotational speed is less than the preset stall speed threshold, the cumulative heat value of the drive motor is determined based on the drive current of the drive motor and the preset stall current threshold, wherein the cumulative heat value is used to characterize the heat value accumulated by the drive motor during the vehicle's operation.

[0008] Based on the accumulated heat value and the preset stall heat value, it is determined whether the drive motor stalls during the vehicle's operation. The preset stall heat value is used to characterize the maximum heat value accumulated by the drive motor from normal vehicle operation to stall.

[0009] In one feasible implementation, when the rotational speed is less than the preset stall speed threshold, determining the cumulative heat value of the drive motor based on the drive current of the drive motor and the preset stall current threshold includes:

[0010] When the rotational speed is less than the preset stall speed threshold, the difference between the drive current of the drive motor and the square of the preset stall current threshold is determined;

[0011] The difference is integrated over time to determine the cumulative heat value corresponding to the drive motor.

[0012] In one feasible implementation, determining whether the drive motor stalls during vehicle operation based on the accumulated heat value and a preset stall heat value includes:

[0013] If the accumulated heat value is greater than or equal to the preset stall heat value, then it is determined that the drive motor stalls during the vehicle's operation.

[0014] If the accumulated heat value is less than the preset stall heat value, then it is determined that the drive motor did not stall during the vehicle's operation.

[0015] In one feasible implementation, after determining whether the drive motor has stalled during vehicle operation based on the accumulated heat value and a preset stall heat value, the stall determination method for the drive motor in the vehicle further includes:

[0016] After determining that the drive motor stalls during vehicle operation and adjusting the current of the drive motor by reducing current and / or frequency, the adjustment speed and adjustment drive current of the drive motor are determined.

[0017] Based on the adjusted drive current and the preset stall current threshold, the cumulative heat adjustment value corresponding to the drive motor is determined;

[0018] If it is determined that the cumulative heat adjustment value is less than or equal to the preset stall heat adjustment value, then it is determined to stop the stall adjustment of the drive motor, wherein the preset stall heat adjustment value is less than the preset stall heat cumulative value;

[0019] If it is determined that the adjusted rotational speed is greater than or equal to the preset stall speed threshold, then it is determined to stop the stall monitoring of the drive motor.

[0020] In one feasible implementation, after determining to stop monitoring the stall of the drive motor if it is determined that the adjusted rotational speed is greater than or equal to the preset stall speed threshold, the method for determining the stall of the drive motor in the vehicle further includes:

[0021] Based on the accumulated heat value and the time of heat accumulation, the heat slope corresponding to the drive motor is determined;

[0022] Based on the heat slope, the cumulative heat adjustment value is subjected to heat attenuation processing until the cumulative heat adjustment value is reduced to a set threshold.

[0023] In one feasible implementation, determining the cumulative heat adjustment value corresponding to the drive motor based on the adjusted drive current and the preset stall current threshold includes:

[0024] Determine the difference between the adjusted drive current and the square of the preset stall current threshold;

[0025] The difference is integrated over time to determine the cumulative heat adjustment value corresponding to the drive motor.

[0026] In one feasible implementation, the preset stalled rotor heat adjustment value is the difference between the preset stalled rotor heat accumulation value and the heat accumulation value.

[0027] In a second aspect, this application provides a stall detection device for a drive motor in a vehicle, the device comprising:

[0028] The acquisition module is used to acquire the speed and drive current of the drive motor in the vehicle during the vehicle's operation.

[0029] The first determining module is used to determine the cumulative heat value of the drive motor based on the drive current of the drive motor and the preset stall current threshold when the rotational speed is less than the preset stall speed threshold. The cumulative heat value is used to characterize the heat value accumulated by the drive motor during the vehicle's operation.

[0030] The second determining module is used to determine whether the drive motor stalls during the vehicle's operation based on the accumulated heat value and the preset stall heat value, wherein the preset stall heat value is used to characterize the maximum heat value accumulated by the drive motor from the normal operation of the vehicle to the stall process.

[0031] In a third aspect of this application, an in-vehicle terminal is provided, comprising: a processor, a memory, and a bus. The memory stores machine-readable instructions executable by the processor. When the in-vehicle terminal is running, the processor communicates with the memory via the bus, and the machine-readable instructions are executed by the processor to perform the steps of the stall determination method for the drive motor in the vehicle as described above.

[0032] In a sixth aspect of this application, this application provides a computer-readable storage medium storing a computer program that, when executed by a processor, performs the steps of the stall determination method for a drive motor in a vehicle as described above.

[0033] The method, apparatus, and vehicle terminal for determining stall of a drive motor in a vehicle provided in this application, compared with the prior art, solve the technical problems of low accuracy and low efficiency in stall identification. The embodiments provided in this application acquire the rotational speed and drive current of the drive motor in the vehicle during driving. When the rotational speed is less than a preset stall speed threshold, the accumulated heat value of the drive motor is determined based on the drive current and the preset stall current threshold. Then, based on the accumulated heat value and the preset stall heat value, it is determined whether the drive motor has stalled during vehicle driving. The embodiments provided in this application can accurately determine the stall status of the drive motor under different output torques, improving the accuracy of stall identification. Furthermore, compared with the prior art method that requires setting thresholds for multiple torque segments to determine motor stall, the embodiments provided in this application improve the efficiency of stall identification, thereby extending the service life of the drive motor. Attached Figure Description

[0034] Figure 1 This is one of the flowcharts of a method for determining the stall of a drive motor in a vehicle, provided in an embodiment of this application.

[0035] Figure 2 A circuit diagram of a method for determining the stall of a drive motor in a vehicle, provided in an embodiment of this application, is shown.

[0036] Figure 3 This is a second flowchart illustrating a method for determining the stall of a drive motor in a vehicle, as provided in an embodiment of this application.

[0037] Figure 4 A structural block diagram of a vehicle drive motor stall determination device provided in an embodiment of this application;

[0038] Figure 5 This is a schematic diagram of the structure of a vehicle-mounted terminal provided in an embodiment of this application.

[0039] Figure 4 and Figure 5 The correspondence between the figure labels and figure titles in the accompanying drawings is as follows:

[0040] 400 A device for determining the stall of a drive motor in a vehicle; 410 An acquisition module; 420 A first determining module; 430 A second determining module; 440 A third determining module; 450 A fourth determining module; 460 A fifth determining module; 470 A sixth determining module; 480 A seventh determining module; 490 An eighth determining module; 4100 A ninth determining module; 500 An on-board terminal; 510 A processor; 520 A memory; 530 A bus. Detailed Implementation

[0041] To better understand the technical solutions provided in the embodiments of this specification, the technical solutions of the embodiments of this specification will be described in detail below with reference to the accompanying drawings and specific embodiments. It should be understood that the embodiments of this specification and the specific features in the embodiments are detailed descriptions of the technical solutions of the embodiments of this specification, rather than limitations on the technical solutions of this specification. In the absence of conflict, the embodiments of this specification and the technical features in the embodiments can be combined with each other.

[0042] In this document, relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, without necessarily requiring or implying any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus 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 apparatus. Without further limitation, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element. The term "two or more" includes two or more cases.

[0043] First, the applicable application scenarios of this application will be introduced. The embodiments provided in this application are applicable to the field of vehicle inspection technology.

[0044] Currently, traditional methods for determining drive motor stall typically rely on the time taken for the drive motor to stall under different output torques. However, this method only works when the output torque remains constant and cannot determine the stall status of the drive motor under different output torques. This results in low accuracy in stall identification. Furthermore, because the transmission path for different output torques is relatively long, damage to the drive motor can occur during signal transmission, leading to low efficiency in stall identification and affecting the lifespan of the drive motor. In addition, traditional stall identification methods cannot reliably and smoothly overcome stall conditions.

[0045] Based on this, the embodiments of this application provide a method, device and vehicle terminal for determining the stall of a drive motor in a vehicle. The embodiments provided by this application solve the technical problems of low accuracy and low efficiency of stall identification in the prior art. The embodiments provided by this application can accurately determine the stall status of the drive motor under different output torques, improve the accuracy and efficiency of stall identification, and thus extend the service life of the drive motor.

[0046] Figure 1 This is one of the flowcharts for a method to determine the stall of a drive motor in a vehicle, provided in an embodiment of this application. Figure 1 As shown, the method for determining the stall of the drive motor in a vehicle provided in this application includes the following steps:

[0047] S101. During the vehicle's operation, obtain the speed and drive current of the drive motor in the vehicle.

[0048] In this step, the embodiments provided in this application can be specifically applied to the drive motor controller, but are not limited to it. During normal vehicle operation or operation under special working conditions, the speed and drive current of the vehicle's drive motor are acquired in real time, and the acquired speed and drive current are transmitted to the drive motor controller.

[0049] The specific working conditions in the embodiments provided in this application include, but are not limited to, the process of climbing a hill.

[0050] S102. When the speed is less than the preset stall speed threshold, the cumulative heat value of the drive motor is determined based on the drive current of the drive motor and the preset stall current threshold, wherein the cumulative heat value is used to characterize the heat value accumulated by the drive motor during vehicle operation.

[0051] In this step, the rotational speed of the drive motor in the vehicle under the current driving state is compared with the preset stall speed threshold to determine whether stall monitoring of the drive motor is required. If the rotational speed is less than the preset stall speed threshold, stall monitoring of the drive motor is determined. At this time, based on the drive current of the drive motor and the preset stall current threshold, the heat value accumulated by the drive motor during vehicle operation is determined, that is, the heat accumulation value corresponding to the drive motor.

[0052] In this embodiment, the preset stall speed threshold is specifically 100 rpm. When the speed is less than 100 rpm, stall monitoring of the drive motor is determined. In this embodiment, the drive current of the drive motor is the effective value of the phase current.

[0053] It is understood that the embodiments provided in this application determine that no stall monitoring will be performed on the drive motor when the rotational speed is greater than or equal to a preset stall speed threshold, and determine that no stall monitoring will be performed on the drive motor when the rotational speed is greater than or equal to 100 rpm.

[0054] The vehicle in the embodiments provided in this application may experience a traffic jam during operation, and the underlying principle is as follows: Figure 2 As shown, Figure 2 This is a circuit diagram illustrating the stall condition of a drive motor in a vehicle, as provided in an embodiment of this application. Figure 2 As shown, under normal operating conditions, the upper and lower three bridges of the IGBT switch on and off at an extremely high frequency. At this time, a sinusoidal three-phase current is formed on the U / V / W three-phase side of the drive motor to ensure that the drive motor outputs normal speed and torque. Under this condition, the upper and lower three bridges of the IGBT will be turned on and off at an extremely high frequency. During the IGBT's turn-on process, a large drive current flows through it, resulting in significant heat generation and a rapid temperature rise. During the IGBT's turn-off process, no current flows through it, and the temperature drops rapidly. Therefore, when the vehicle is in an off-road scenario with a large slope and insufficient driving force, the drive motor outputs a large torque but the speed is 0, a condition known as stall.

[0055] In the above scenario, since the vehicle is in a hovering state, the motor speed is 0, the motor's three-phase current is no longer a sine wave but DC, the IGBT no longer switches between states, but one bridge is in a constantly open state, and at this time, due to the large torque of the entire vehicle, the drive current is large. Under these circumstances, the temperature rise of the IGBT will be particularly high. If measures are not taken in time, the IGBT will be damaged, leading to the vehicle breaking down. Therefore, the stall determination method in the embodiments provided in this application is needed to accurately determine the time of stall occurrence, thereby accurately avoiding or reducing IGBT damage and vehicle breakdown.

[0056] S103. Based on the above-mentioned accumulated heat value and the preset accumulated stall heat value, determine whether the drive motor stalls during the driving of the vehicle, wherein the preset accumulated stall heat value is used to characterize the maximum heat value accumulated by the drive motor from the normal driving of the vehicle to the stall process.

[0057] In this step, after determining the cumulative heat value corresponding to the drive motor, the cumulative heat value corresponding to the drive motor is compared with the preset cumulative heat value for stall. If the cumulative heat value is greater than or equal to the preset cumulative heat value for stall, it is determined that the drive motor has stalled during vehicle operation; if the cumulative heat value is less than the preset cumulative heat value for stall, it is determined that the drive motor has not stalled during vehicle operation.

[0058] Understandable, if Q1≥Q m If Q1≤Q m This confirms that the drive motor did not stall during vehicle operation.

[0059] Among them, Q m Used to characterize the preset stalled rotor heat accumulation value, and Q m The value is the integral of the square of the peak current over time T when the drive motor is stalled and the output peak current is stalled. Time T is the same as the time it takes for the IGBT temperature to reach the over-temperature threshold under this drive current. Q1 is used to characterize the cumulative heat value of the drive motor.

[0060] For example, step S102 includes: when the speed is less than the preset stall speed threshold, determining the difference between the drive current of the drive motor and the square of the preset stall current threshold; performing time integration on the difference to determine the heat accumulation value corresponding to the drive motor.

[0061] The formula for determining the cumulative heat value corresponding to the drive motor is as follows:

[0062]

[0063] Where Q1 is used to characterize the cumulative heat value corresponding to the drive motor; I1 is used to characterize the drive current; Ia is used to characterize the preset stall current threshold, and the preset stall current threshold is the current that can be stabilized at the highest junction temperature of the IGBT under a certain constant torque output.

[0064] The method for determining stall of a drive motor in a vehicle provided in this application addresses the technical problems of low accuracy and efficiency in stall identification compared to existing technologies. This method acquires the rotational speed and drive current of the drive motor during vehicle operation. When the rotational speed is less than a preset stall speed threshold, it determines the accumulated heat value of the drive motor based on the drive current and the preset stall current threshold. Then, based on the accumulated heat value and the preset stall heat value, it determines whether the drive motor has stalled during vehicle operation. This method accurately determines the stall status of the drive motor under different output torques, improving the accuracy and efficiency of stall identification and extending the service life of the drive motor.

[0065] Figure 3 This is a second flowchart of a method for determining the stall of a drive motor in a vehicle, provided in an embodiment of this application. Figure 3 As shown, the method for determining the stall of the drive motor in a vehicle includes the following steps:

[0066] S301. During the vehicle's operation, obtain the speed and drive current of the drive motor in the vehicle.

[0067] S302. When the speed is less than the preset stall speed threshold, the cumulative heat value of the drive motor is determined based on the drive current of the drive motor and the preset stall current threshold, wherein the cumulative heat value is used to characterize the heat value accumulated by the drive motor during the vehicle's operation.

[0068] S303. Based on the above-mentioned accumulated heat value and the preset accumulated stall heat value, determine whether the drive motor stalls during the driving of the vehicle, wherein the preset accumulated stall heat value is used to characterize the maximum heat value accumulated by the drive motor from the normal driving of the vehicle to the stall process.

[0069] S304. After determining that the drive motor stalls during the operation of the vehicle, and after adjusting the current of the drive motor by reducing the current and / or reducing the frequency to achieve stall adjustment, determine the adjustment speed and adjustment drive current of the drive motor.

[0070] In this step, the embodiment provided in this application determines that the drive motor is stuck during vehicle operation. At this time, it is necessary to reduce the current and / or frequency of the drive motor. After processing, based on the adjustment speed and adjustment drive current of the drive motor, the cumulative heat adjustment value is continuously calculated. In order to prevent the normal identification of the stuck condition when the torque changes and the drive motor enters and exits the stuck condition, it is necessary to calculate the cumulative heat adjustment value to determine whether the drive motor exits the stuck adjustment and stuck monitoring, or whether it re-enters the stuck condition. This can better protect the drive motor and prevent permanent damage caused by the overheating and demagnetization of the drive motor.

[0071] Understandably, the current reduction of the drive motor in the embodiments provided in this application can be specifically described as: derating, that is, reducing the external characteristic torque of the controller in the drive motor. The peak current controlled by the drive motor is related to the external characteristic torque. The larger the torque, the larger the current. And the larger the current, the greater the heat generation of the IGBT. By directly reducing the current, the heat generation of the IGBT can be directly reduced.

[0072] The specific method to reduce the carrier frequency of the IGBT in the drive motor is to reduce the IGBT carrier frequency from 8-10kHz to 2kHz. This is because the IGBT has relatively large turn-on and turn-off losses, but its NVH (Noise, Vibration, and Harshness) and torque control accuracy are relatively good. If it is found that the drive motor needs to be locked, the carrier frequency can be directly reduced to 2kHz. At this time, since the speed is almost 0, it will not affect the torque control accuracy, but some NVH performance will be sacrificed.

[0073] S305. Based on the above-mentioned adjusted drive current and the above-mentioned preset stall current threshold, determine the heat accumulation adjustment value corresponding to the above-mentioned drive motor.

[0074] In this step, after adjusting the drive motor to lock up, it is necessary to continuously calculate the cumulative heat adjustment value. Specifically, this involves determining the difference between the adjusted drive current and the square of the preset lock up current threshold, and then integrating this difference over time to determine the corresponding cumulative heat adjustment value for the drive motor. The formula for determining the cumulative heat adjustment value is as follows:

[0075]

[0076] Where Q2 is used to characterize the cumulative heat adjustment value corresponding to the drive motor; I2 is used to characterize the adjusted drive current; Ia is used to characterize the preset stall current threshold, and the preset stall current threshold is the current that can be stabilized at the highest junction temperature of the IGBT under a certain constant torque output.

[0077] In the above scenario, when I2 is less than Ia, Q2 will continue to decrease, indicating that the vehicle temperature is in a heat dissipation state; when I2 is greater than Ia, Q2 will continue to rise, indicating that the vehicle temperature is in a dangerous state.

[0078] S306. If it is determined that the above-mentioned cumulative heat adjustment value is less than or equal to the above-mentioned preset stall heat adjustment value, then it is determined to stop the stall adjustment of the above-mentioned drive motor, wherein the above-mentioned preset stall heat adjustment value is less than the preset stall heat cumulative value.

[0079] In this step, after determining Q2≤Q n When this occurs, the stall adjustment of the aforementioned drive motor is stopped, wherein the second preset stall heat is represented by Q. n To express.

[0080] It is understood that the aforementioned preset stalled rotor heat adjustment value is the difference between the aforementioned preset stalled rotor heat accumulation value and the aforementioned heat accumulation value. Assuming that Q in the embodiments provided in this application... n It can be specific but is not limited to Q. n =Q m -Q.

[0081] S307. If it is determined that the above-mentioned adjusted speed is greater than or equal to the above-mentioned preset stall speed threshold, then it is determined to stop the stall monitoring of the above-mentioned drive motor.

[0082] In this step, when the adjusted speed is greater than or equal to the preset stall speed threshold of 100 rpm, it indicates that the drive motor has exited the stall state, and at this time, the stall monitoring of the drive motor is stopped.

[0083] S308. Based on the above accumulated heat value and the heat accumulation time, determine the heat slope corresponding to the above drive motor.

[0084] In this step, it is assumed that the time for heat accumulation is 5 seconds; the heat slope corresponding to the drive motor is represented by S, where S = Q / 5s.

[0085] S309. Based on the above heat slope, perform heat attenuation processing on the above heat cumulative adjustment value until the above heat cumulative adjustment value is reduced to the set threshold.

[0086] In this step, after determining to stop monitoring the stall of the aforementioned drive motor, it is necessary to perform heat attenuation processing on the accumulated heat adjustment value. Specifically, the heat is attenuated according to the heat slope of S = Q / 5s until the accumulated heat adjustment value is reduced to the set threshold.

[0087] In the above-mentioned embodiments, the threshold values ​​set in the embodiments provided by this application can be customized according to different application scenarios. Specifically, the threshold value set in the embodiments provided by this application is 0.

[0088] Here, if the drive motor exits the previous stall monitoring and immediately enters the stall monitoring again, the heat accumulation value will continue to accumulate from the previous heat accumulation value. This can ensure the accuracy of the stall status judgment to the greatest extent and prevent IGBT overheating from causing other abnormal situations.

[0089] The method for determining the stall of a drive motor in a vehicle provided in this application, compared with the prior art, solves the technical problems of low accuracy and low efficiency in stall identification in the prior art. The method obtains the rotational speed and drive current of the drive motor during vehicle operation. When the rotational speed is less than a preset stall speed threshold, it determines the cumulative heat value of the drive motor based on the drive current and the preset stall current threshold. Then, based on the cumulative heat value and the preset stall heat value, it determines whether the drive motor has stalled during vehicle operation. The method can accurately determine the stall status of the drive motor under different output torques, improving the accuracy of stall identification. Compared with the prior art method that requires setting thresholds for multiple torque segments to determine motor stall, this method improves the efficiency of stall identification, thereby extending the service life of the drive motor. Furthermore, the method can calculate the cumulative heat adjustment value to determine whether the drive motor has exited stall adjustment, stall monitoring, or re-entered stall, thus better protecting the drive motor and preventing permanent damage caused by overheating and demagnetization.

[0090] Please see Figure 4 , Figure 4 This is a structural block diagram of a vehicle drive motor stall determination method apparatus 400 provided in an embodiment of this application. The vehicle drive motor stall determination method apparatus 400 includes:

[0091] The acquisition module 410 is used to acquire the speed and drive current of the drive motor in the vehicle during the vehicle's operation.

[0092] The first determining module 420 is used to determine the cumulative heat value of the drive motor based on the drive current of the drive motor and the preset stall current threshold when the speed is less than the preset stall speed threshold. The cumulative heat value is used to characterize the heat value accumulated by the drive motor during the vehicle's operation.

[0093] The second determining module 430 is used to determine whether the drive motor is stalled during the driving of the vehicle based on the above-mentioned accumulated heat value and the preset stalled heat value, wherein the preset stalled heat value is used to characterize the maximum heat value accumulated by the drive motor from the normal driving of the vehicle to the stalled process.

[0094] The third determining module 440 is used to determine the adjustment speed and adjustment drive current of the drive motor after determining that the drive motor is stalled during the driving of the vehicle and after adjusting the stall by reducing the current and / or frequency of the drive motor.

[0095] The fourth determining module 450 is used to determine the difference between the square of the adjusted drive current and the preset stall current threshold.

[0096] The fifth determining module 460 is used to perform time integration processing on the above difference to determine the cumulative heat adjustment value corresponding to the above drive motor.

[0097] The sixth determining module 470 is used to determine to stop the stall adjustment of the drive motor if it is determined that the above-mentioned cumulative heat adjustment value is less than or equal to the above-mentioned preset stall heat adjustment value, wherein the above-mentioned preset stall heat adjustment value is less than the preset stall heat cumulative value.

[0098] The seventh determining module 480 is used to determine to stop the stall monitoring of the drive motor if it is determined that the adjusted speed is greater than or equal to the preset stall speed threshold.

[0099] The eighth determining module 490 is used to determine the heat slope corresponding to the drive motor based on the above-mentioned heat accumulation value and heat accumulation time.

[0100] The ninth determining module 4100 is used to perform heat attenuation processing on the above-mentioned heat accumulation adjustment value until the above-mentioned heat accumulation adjustment value is reduced to a set threshold.

[0101] For example, the preset stalled rotor heat adjustment value is the difference between the preset stalled rotor heat accumulation value and the heat accumulation value.

[0102] For example, the first determining module 420 is specifically used for:

[0103] When the speed is less than the preset stall speed threshold, the difference between the drive current of the drive motor and the square of the preset stall current threshold is determined.

[0104] The above difference is integrated over time to determine the cumulative heat value corresponding to the drive motor.

[0105] For example, the second determining module 430 is specifically used for:

[0106] If the above-mentioned cumulative heat value is greater than or equal to the preset cumulative stall heat value, it is determined that the above-mentioned drive motor stalls during the driving of the above-mentioned vehicle.

[0107] If the above-mentioned cumulative heat value is less than the preset cumulative stall heat value, it is determined that the drive motor did not stall during the vehicle's operation.

[0108] The vehicle drive motor stall determination device 400 provided in this application embodiment solves the technical problems of low accuracy and low efficiency of stall identification in the prior art. This embodiment acquires the speed and drive current of the drive motor during vehicle operation. When the speed is less than a preset stall speed threshold, it determines the corresponding heat accumulation value of the drive motor based on the drive current and the preset stall current threshold. Then, based on the heat accumulation value and the preset stall heat accumulation value, it determines whether the drive motor has stalled during vehicle operation. This embodiment can accurately determine the stall status of the drive motor under different output torques, improving the accuracy of stall identification. Compared with the prior art method of determining motor stall by setting thresholds for multiple torque segments, this embodiment improves the efficiency of stall identification, thereby extending the service life of the drive motor. Furthermore, this embodiment can determine whether the drive motor has exited stall adjustment, stall monitoring, or re-entered stall by calculating the heat accumulation adjustment value. This better protects the drive motor and prevents permanent damage caused by overheating and demagnetization.

[0109] Please see Figure 5 , Figure 5 This application provides a schematic diagram of the structure of an in-vehicle terminal according to an embodiment. Figure 5 As shown, the vehicle terminal 500 includes a processor 510, a memory 520, and a bus 530.

[0110] Memory 520 stores machine-readable instructions executable by processor 510. When the vehicle terminal 500 is running, processor 510 and memory 520 communicate via bus 530. When the machine-readable instructions are executed by processor 510, they can perform the operations described above. Figures 1 to 2 The steps of the method for determining the stall of the drive motor in the vehicle in the method embodiment shown are described in detail in the method embodiment, and will not be repeated here.

[0111] This application also provides a computer-readable storage medium storing a computer program, which, when executed by a processor, can perform the above-described actions. Figures 1 to 2The steps of the method for determining the stall of the drive motor in the vehicle in the method embodiment shown are described in detail in the method embodiment, and will not be repeated here.

[0112] Those skilled in the art will understand that, for the sake of convenience and brevity, the specific working processes of the systems, devices, and units described above can be referred to the corresponding processes in the foregoing method embodiments, and will not be repeated here.

[0113] It should be noted that the descriptions of each embodiment in the above embodiments have different focuses. For parts that are not described in detail in a certain embodiment, please refer to the relevant descriptions in other embodiments.

[0114] Those skilled in the art will understand that embodiments of this application can be provided as methods, systems, or computer program products. Therefore, this application can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, this application can take the form of a computer program product embodied on one or more computer-readable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-readable program code.

[0115] This application is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of this application. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded computer, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, create a machine for implementing the flowchart illustrations. Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0116] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0117] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0118] This application also provides a computer program product, which includes computer software instructions that, when executed on a processing device, cause the processing device to execute a process for determining the stall of a drive motor in a vehicle.

[0119] A computer program product includes one or more computer instructions. When the computer program instructions are loaded and executed on a computer, all or part of the flow or function according to the embodiments of this application is generated. The computer may be a general-purpose computer, a special-purpose computer, a computer network, or other programmable device. The computer instructions may be stored in a computer-readable storage medium or transmitted from one computer-readable storage medium to another. For example, computer instructions may be transmitted from one website, computer, server, or data center to another website, computer, server, or data center via wired (e.g., coaxial cable, fiber optic, digital subscriber line (DSL)) or wireless (e.g., infrared, wireless, microwave, etc.) means. The computer-readable storage medium may be any available medium that a computer can store or a data storage device such as a server or data center that integrates one or more available media. The available media may be magnetic media (e.g., floppy disks, hard disks, magnetic tapes), optical media (e.g., DVDs), or semiconductor media (e.g., solid-state drives (SSDs)).

[0120] Those skilled in the art will clearly understand that, for the sake of convenience and brevity, the specific working processes of the systems, devices, and units described above can be referred to the corresponding processes in the foregoing method embodiments, and will not be repeated here.

[0121] In the several embodiments provided in this application, it should be understood that the disclosed devices, apparatuses, and methods can be implemented in other ways. For example, the apparatus embodiments described above are merely illustrative; for instance, the division of units is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the coupling or direct coupling or communication connection shown or discussed may be through some interfaces, or indirect coupling or communication connection between devices or units, and may be electrical, mechanical, or other forms.

[0122] The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs.

[0123] Furthermore, the functional units in the various embodiments of this application can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The integrated unit can be implemented in hardware or as a software functional unit.

[0124] If the integrated unit is implemented as a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, or all or part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods of the various embodiments of this application. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0125] The above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application.

[0126] Although preferred embodiments have been described in this specification, those skilled in the art, upon learning the basic inventive concept, can make other changes and modifications to these embodiments. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments as well as all changes and modifications falling within the scope of this specification.

[0127] Obviously, those skilled in the art can make various modifications and variations to this specification without departing from its spirit and scope. Therefore, if such modifications and variations fall within the scope of the claims and their equivalents, this specification is also intended to include such modifications and variations.

Claims

1. A method for determining stall of a drive motor in a vehicle, characterized in that, The method for determining the stall of the drive motor in the vehicle includes: During vehicle operation, the rotational speed and drive current of the drive motor in the vehicle are acquired; When the rotational speed is less than a preset stall speed threshold, the cumulative heat value of the drive motor is determined based on the drive current of the drive motor and the preset stall current threshold, wherein the cumulative heat value is used to characterize the heat value accumulated by the drive motor during the vehicle's operation. Based on the accumulated heat value and the preset stall heat value, it is determined whether the drive motor stalls during the vehicle's operation. The preset stall heat value is used to characterize the maximum heat value accumulated by the drive motor from normal vehicle operation to stall. After determining whether the drive motor has stalled during vehicle operation based on the accumulated heat value and the preset stall heat value, the method for determining the stall of the drive motor in the vehicle further includes: After determining that the drive motor stalls during vehicle operation and adjusting the current of the drive motor by reducing current and / or frequency, the adjustment speed and adjustment drive current of the drive motor are determined. Based on the adjusted drive current and the preset stall current threshold, the cumulative heat adjustment value corresponding to the drive motor is determined; If it is determined that the cumulative heat adjustment value is less than or equal to the preset stall heat adjustment value, then it is determined to stop the stall adjustment of the drive motor, wherein the preset stall heat adjustment value is less than the preset stall heat cumulative value; If it is determined that the adjusted rotational speed is greater than or equal to the preset stall speed threshold, then it is determined to stop the stall monitoring of the drive motor.

2. The method for determining stall of a drive motor in a vehicle according to claim 1, characterized in that, When the rotational speed is less than the preset stall speed threshold, the step of determining the cumulative heat value of the drive motor based on the drive current of the drive motor and the preset stall current threshold includes: When the rotational speed is less than the preset stall speed threshold, the difference between the drive current of the drive motor and the square of the preset stall current threshold is determined; The difference is integrated over time to determine the cumulative heat value corresponding to the drive motor.

3. The method for determining stall of a drive motor in a vehicle according to claim 1, characterized in that, The step of determining whether the drive motor stalls during vehicle operation based on the accumulated heat value and a preset stall heat value includes: If the accumulated heat value is greater than or equal to the preset stall heat value, then it is determined that the drive motor stalls during the vehicle's operation. If the accumulated heat value is less than the preset stall heat value, then it is determined that the drive motor did not stall during the vehicle's operation.

4. The method for determining stall of a drive motor in a vehicle according to claim 1, characterized in that, After determining that the adjusted rotational speed is greater than or equal to the preset stall speed threshold, and then determining to stop stall monitoring of the drive motor, the stall determination method for the drive motor in the vehicle further includes: Based on the accumulated heat value and the time of heat accumulation, the heat slope corresponding to the drive motor is determined; Based on the heat slope, the cumulative heat adjustment value is subjected to heat attenuation processing until the cumulative heat adjustment value is reduced to a set threshold.

5. The method for determining stall of a drive motor in a vehicle according to claim 1, characterized in that, The step of determining the cumulative heat adjustment value corresponding to the drive motor based on the adjusted drive current and the preset stall current threshold includes: Determine the difference between the adjusted drive current and the square of the preset stall current threshold; The difference is integrated over time to determine the cumulative heat adjustment value corresponding to the drive motor.

6. The method for determining stall of a drive motor in a vehicle according to claim 1, characterized in that, The preset stalled rotor heat adjustment value is the difference between the preset stalled rotor heat accumulation value and the heat accumulation value.

7. A device for determining the stall of a drive motor in a vehicle, characterized in that, The stall detection device for the drive motor in the vehicle includes: The acquisition module is used to acquire the speed and drive current of the drive motor in the vehicle during the vehicle's operation. The first determining module is used to determine the cumulative heat value of the drive motor based on the drive current of the drive motor and the preset stall current threshold when the rotational speed is less than the preset stall speed threshold. The cumulative heat value is used to characterize the heat value accumulated by the drive motor during the vehicle's operation. The second determining module is used to determine whether the drive motor stalls during the vehicle's operation based on the accumulated heat value and the preset stall heat value, wherein the preset stall heat value is used to characterize the maximum heat value accumulated by the drive motor from the normal operation of the vehicle to the stall process; The third determining module is used to determine the adjusting speed and adjusting drive current of the drive motor after determining that the drive motor is stalled during the driving of the vehicle and after adjusting the stall by reducing the current and / or frequency of the drive motor. The fourth determining module is used to determine the cumulative heat adjustment value corresponding to the drive motor based on the adjusted drive current and the preset stall current threshold. The fifth determining module is used to determine to stop the stall adjustment of the drive motor if the cumulative heat adjustment value is determined to be less than or equal to the preset stall heat adjustment value, wherein the preset stall heat adjustment value is less than the preset stall heat cumulative value. The sixth determining module is used to determine to stop monitoring the stall of the drive motor if it is determined that the adjusted speed is greater than or equal to the preset stall speed threshold.

8. A vehicle-mounted terminal, characterized in that, include: The system includes a processor, a memory, and a bus. The memory stores machine-readable instructions executable by the processor. When the vehicle terminal is running, the processor communicates with the memory via the bus. The machine-readable instructions are executed by the processor to perform the steps of the stall determination method for the drive motor in the vehicle as described in any one of claims 1-6.

9. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores a computer program that, when executed by a processor, performs the steps of the stall determination method for the drive motor in a vehicle as described in any one of claims 1-6.

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