A motor-based differential limit method, device, equipment and storage medium

Abstract

The application relates to the field of automobile driving technology and provides a motor-based differential limiting method, device, equipment and storage medium, the method comprising the following steps: obtaining an initial request torque, an output torque, a speed difference and preset calibration torque information; determining a torque threshold corresponding to the speed difference according to the speed difference and the calibration torque information; comparing the speed difference with a preset speed difference threshold; comparing the output torque with the torque threshold to obtain a comparison result; and determining and executing a limiting measure based on the comparison result to limit the initial request torque. The application jointly judges the differential limiting demand through the speed difference and the output torque, can effectively improve the matching degree of the limiting measure and the actual working condition, can reduce the control delay by limiting the initial request torque, effectively improves the timeliness, accuracy and safety of the differential limiting measure, and greatly reduces the control delay and hardware failure risk in the differential limiting process.

Description

Technical Field

[0001] This application relates to the field of automotive drive technology, specifically to a method, apparatus, device, and storage medium for differential speed limiting based on an electric motor. Background Technology

[0002] The drive motor is a core component of new energy vehicles, used to provide the power for the vehicle to move forward during driving. The output torque of the drive motor is distributed to the drive wheels through the differential to create a speed difference. During the driving process, the speed difference between the left and right drive wheels will inevitably increase due to steering, slippage, and other situations. In order to ensure hardware safety and driving safety, the speed difference needs to be limited under certain circumstances.

[0003] In existing differential speed limiting methods, a preset speed difference is generally used as a reference value. The actual collected speed difference is then compared with the preset speed difference, and the vehicle controller adjusts the current speed difference based on the comparison. For example, patent CN114954027A discloses a method that obtains the current wheel speed difference and compares it with a preset wheel speed difference, and controls the vehicle controller to adjust the motor torque based on the comparison result. The existing differential speed limiting methods have the following drawbacks:

[0004] Using only the actual collected speed difference as the basis for judgment, the torque output of the drive motor is not considered in the process of controlling the torque through the vehicle controller. This fails to fully reflect the differential speed limit adjustment requirements, resulting in a mismatch between the limit measures and the actual operating conditions of the vehicle. This can easily lead to untimely or inaccurate limits, causing control delays and increasing the risk of hardware wear and failure. Summary of the Invention

[0005] Given that the differential speed limit measures in the prior art described above cannot fully correspond to the differential speed limit requirements, resulting in a mismatch between the limit measures and the actual operating conditions of the vehicle, it is easy for the limit to be untimely or inaccurate, causing control delays and increasing the risk of hardware wear and failure. Therefore, this application provides a differential speed limit method, device, equipment and storage medium based on an electric motor to solve the above-mentioned technical problems.

[0006] In a first aspect, the present invention provides a differential speed limiting method based on a motor, comprising:

[0007] The system acquires the initial requested torque input to the drive motor, the output torque of the drive motor, the speed difference of the drive wheels, and preset calibration torque information.

[0008] Based on the speed difference and the calibrated torque information, determine the torque threshold corresponding to the speed difference;

[0009] The speed difference is compared with a preset speed difference threshold, and the output torque is compared with the torque threshold to obtain the comparison result;

[0010] Based on the comparison results, a limit measure is determined and implemented to limit the initial requested torque.

[0011] Secondly, the present invention provides a differential speed limiting device based on a motor, comprising:

[0012] The data acquisition module is used to acquire the initial requested torque input to the drive motor, the output torque of the drive motor, the speed difference of the drive wheels, and preset calibration torque information;

[0013] The data processing module is used to determine the torque threshold corresponding to the speed difference based on the speed difference and the calibrated torque information;

[0014] The parameter comparison module is used to compare the speed difference with a preset speed difference threshold and the output torque with the torque threshold to obtain the comparison result.

[0015] An execution module is used to determine and execute limiting measures based on the comparison results to limit the initial requested torque.

[0016] Thirdly, the present invention provides an electronic device, comprising:

[0017] One or more processors;

[0018] A storage device for storing one or more programs, which, when executed by one or more processors, cause the electronic device to implement a motor-based differential speed limiting method as described above.

[0019] Fourthly, the present invention provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a computer processor, causes the computer to perform one of the above-described methods for differential speed limiting based on a motor.

[0020] The aforementioned method, apparatus, device, and storage medium for differential speed limiting based on a motor first acquires the initial requested torque input to the drive motor, the output torque of the drive motor, the speed difference of the drive wheels, and preset calibration torque information. Based on the speed difference and calibration torque information, a torque threshold corresponding to the speed difference is determined. Then, the speed difference is compared with the preset speed difference threshold, and the output torque is compared with the torque threshold to obtain the comparison result. Finally, based on the comparison result, a limiting measure is determined and executed to limit the initial requested torque. By jointly determining the differential speed limiting requirement through the speed difference and output torque, the matching degree between the limiting measure and the actual working condition can be effectively improved. By limiting the initial requested torque, control delay can be reduced, effectively improving the timeliness, accuracy, and safety of the differential speed limiting measure, and greatly reducing the control delay and hardware failure risk in the differential speed limiting process.

[0021] It should be understood that the above general description and the following detailed description are exemplary and explanatory only, and do not limit this application. Attached Figure Description

[0022] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this application and, together with the description, serve to explain the principles of this application. It is obvious that the drawings described below are merely some embodiments of this application, and those skilled in the art can obtain other drawings based on these drawings without any inventive effort. In the drawings:

[0023] Figure 1 This is a flowchart illustrating a motor-based differential speed limit method in an exemplary embodiment of this application;

[0024] Figure 2 The calibration torque information shown in an exemplary embodiment of this application includes the safe speed difference-torque graph and the limit speed difference-torque graph.

[0025] Figure 3 This is a schematic diagram of the structure of a motor-based differential speed limiting device shown in an exemplary embodiment of this application;

[0026] Figure 4 A schematic diagram of the structure of a computer system suitable for implementing the electronic device of the present application is shown. Detailed Implementation

[0027] The embodiments of the present invention will be described below with reference to the accompanying drawings and preferred embodiments. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of the present invention. It should be understood that the preferred embodiments are only for illustrating the present invention and not for limiting the scope of protection of the present invention.

[0028] It should be noted that the illustrations provided in the following embodiments are only schematic representations of the basic concept of the present invention. Therefore, the drawings only show the components related to the present invention and are not drawn according to the actual number, shape and size of the components in the actual implementation. In the actual implementation, the form, quantity and proportion of each component can be changed according to actual needs, and the layout of the components may also be more complex.

[0029] In the following description, numerous details are explored to provide a more thorough explanation of embodiments of the invention. However, it will be apparent to those skilled in the art that embodiments of the invention may be practiced without these specific details. In other embodiments, well-known structures and devices are shown in block diagram form rather than in detail to avoid obscuring embodiments of the invention.

[0030] First, it needs to be clarified that current technology for differential speed limiting relies solely on the actual collected speed difference as the basis for judgment. When controlling torque through the vehicle controller, the reasonableness of the drive motor's output torque is not considered, failing to fully reflect the differential speed limit adjustment requirements. This leads to a mismatch between the limiting measures and the vehicle's actual operating conditions, easily resulting in untimely or inaccurate limiting, causing control delays and increasing the risk of hardware wear and failure. For example, in some scenarios, a brief vehicle slippage causes a momentary increase in the speed difference, while the drive motor's output torque remains normal. In such cases, the driver's control can quickly restore the normal speed difference. However, under current control logic, the drive motor's output torque will be reduced, causing a sharp decrease in vehicle power. This is not only detrimental to handling but also leads to a mismatch between the change in output torque and the change in speed difference. This results in a mismatch in the movement of hardware components such as differential gears, drive motor output shafts, and reducers, exacerbating hardware wear. Furthermore, vehicle controller control is generally achieved through CAN (Controller Area Network). Network (Controller Area Network) signals, as a signal transmission method, have a communication delay compared to independent controllers or control units. This is not conducive to timely escape from extreme operating conditions when the speed difference or torque is too large, increasing the risk of hardware failure and, to some extent, also increasing the risk of control delay during differential speed limiting.

[0031] To address the aforementioned deficiencies, this application provides a method, apparatus, device, and storage medium for limiting the differential speed of a motor, as illustrated in the following embodiments:

[0032] In one embodiment, please refer to Figure 1 This application exemplarily illustrates a differential speed limiting method based on a motor, specifically including the following steps:

[0033] Step S110: Obtain the initial requested torque input to the drive motor, the output torque of the drive motor, the speed difference of the drive wheels, and the preset calibration torque information;

[0034] Step S120: Determine the torque threshold corresponding to the speed difference based on the speed difference and the calibrated torque information;

[0035] Step S130: Compare the speed difference with a preset speed difference threshold, and compare the output torque with a torque threshold to obtain the comparison result;

[0036] Step S140: Determine and implement limiting measures based on the comparison results to limit the initial requested torque.

[0037] For the above steps, determining the differential speed limit requirement by combining the speed difference and output torque can effectively improve the matching degree between the limit measures and the actual operating conditions. By limiting the initial requested torque, control delay can be reduced, effectively improving the timeliness, accuracy and safety of the differential speed limit measures, and greatly reducing the control delay and hardware failure risk in the differential speed limit process. The following is a detailed explanation of each step:

[0038] In step S110, the initial requested torque input to the drive motor, the output torque of the drive motor, the speed difference of the drive wheels, and the preset calibration torque information are obtained.

[0039] Here, the drive motor refers to the motor that provides power to the vehicle. It's worth noting that in the process of providing power to the vehicle, the drive motor controller typically receives a request signal from the driver's operation, such as pressing the accelerator pedal. The drive motor then outputs the corresponding actual torque based on this request signal. Therefore, the initial requested torque should be understood as the request signal received by the drive motor; that is, the initial requested torque is a virtual torque representing how much torque the drive motor needs to output. Its specific form can include, but is not limited to, digital or analog signals issued by the drive motor controller. The output torque, on the other hand, is the torque that the drive motor outputs based on the input signal. The actual output torque of the requested signal can be calculated by obtaining operating status parameters such as motor power and speed. Under normal operating conditions of the drive motor, if no processing is performed on the initial requested torque, the output torque of the drive motor should be equal to the initial requested torque. However, if the initial requested torque is limited or processed, so that the initial requested torque is not actually fully input to the drive motor, the output result of the drive motor may change. This limiting or processing can be performed inside or outside the drive motor. Therefore, before any operation is performed on the initial requested torque, the torque described below can refer to either the initial requested torque or the output torque.

[0040] Wheel speed difference refers to the difference in rotational speed between the left and right drive wheels after receiving the output torque provided by the drive motor. It can be obtained through devices such as wheel speed sensors. It can be understood that a differential is set between the drive wheels to balance the amount of motion of the left and right wheels when turning. When the speed difference is too large, it indicates that the amount of motion of the two wheels is extremely uneven, which is likely to cause slippage, oversteering, etc., and may even lead to the transmission components reaching the extreme stress condition, resulting in damage or failure.

[0041] The calibration torque information refers to the data used to calibrate the torque during the vehicle calibration process. It is important to understand that the torque calibration of the vehicle's drive motor is based on a range of speed differences. In other words, the calibrated data is usually a graph showing the relationship between the speed difference and the maximum torque, with the speed difference and the maximum torque corresponding to that speed difference as the coordinate axes.

[0042] In step S120, the torque threshold corresponding to the speed difference is determined based on the speed difference and the calibrated torque information;

[0043] It is understood that the relationship between the calibration torque information and the speed difference has been explained in the aforementioned step S110. Therefore, based on the calibration torque information, the maximum torque set during calibration corresponding to the speed difference can be determined accordingly, i.e., the torque threshold, based on the real-time acquired speed difference.

[0044] In this embodiment, an exemplary scheme for determining a torque threshold based on the speed difference and calibrated torque information is shown. Step S120, that is, the step of determining the torque threshold corresponding to the speed difference based on the speed difference and calibrated torque information, specifically includes the following steps:

[0045] The calibration torque information includes the safe speed difference-torque graph and the limit speed difference-torque graph. Based on the speed difference, the safe torque and the limit torque corresponding to the speed difference are determined from the safe speed difference-torque graph and the limit speed difference-torque graph, respectively.

[0046] The safe torque is used as the first torque threshold, and the ultimate torque is used as the second torque threshold. The torque threshold includes the first torque threshold and the second torque threshold.

[0047] Regarding the above steps, it is understood that the calibration torque information includes at least two sets of calibration relationships between speed difference and torque, namely two sets of speed difference-torque graphs: a safe speed difference-torque graph and a limit speed difference-torque graph. These correspond to the speed difference and torque when the safe operating condition and the limit operating condition are reached, respectively. It is easy to understand that the safe operating condition refers to the operating condition in which the drive motor, drive wheel, or differential can operate safely when working at a certain speed difference and torque. Once the speed difference or torque exceeds the safe operating condition, there may be safety risks such as operation lag and feedback delay. The limit operating condition refers to the operating condition when the hardware reaches its limit. Once the speed difference or torque exceeds the limit operating condition, the risk of major failures such as stress fatigue, failure, and damage of transmission components will increase significantly, leading to a sharp increase in the risk of accidents.

[0048] Under ideal vehicle operating conditions, the operating range should not exceed safe operating conditions for extended periods, nor should it exceed extreme operating conditions. Based on this, please refer to [link / reference needed]. Figure 2 , Figure 2 The calibrated torque information in this embodiment includes a safe speed difference-torque graph and a limit speed difference-torque graph. Both graphs use the speed difference on the x-axis as the independent variable and the torque on the y-axis. The graphs represent the safe torque and limit torque corresponding to each speed difference. The lower left region of the safe speed difference-torque graph indicates that the torque is under safe operating conditions. The region between the safe speed difference-torque graph and the limit speed difference-torque graph indicates that the torque exceeds the safe operating conditions but does not exceed the limit operating conditions. The upper right region of the limit speed difference-torque graph indicates that the torque exceeds the limit operating conditions. By using the speed difference obtained under the current operating conditions and the pre-calibrated safe speed difference-torque graph and limit speed difference-torque graph, the safe torque and limit torque corresponding to the speed difference can be determined and used as the first torque threshold and the second torque threshold, respectively. This allows for the evaluation of the safety of the initial requested torque in subsequent steps based on the first torque threshold and the second torque threshold.

[0049] Regarding the above implementation methods and Figure 2 The two graphs shown primarily use the torque corresponding to a certain speed difference as an evaluation index for safety. The subject of evaluation is torque, and the speed difference, as the final manifestation of torque, is applied in the above steps. It is worth noting that the speed difference itself, as an indicator of the differential's working state, also has its own value for independent evaluation. Therefore, in subsequent steps of this method, a determination is made as to whether the speed difference exceeds the threshold corresponding to the speed difference, which serves as the basis for processing the initial requested torque. This will be explained in detail in the following steps.

[0050] It should be understood that, in the above embodiments, to avoid redundancy, the torque described may refer to either the initial requested torque or the output torque before any operation is performed on the initial requested torque.

[0051] For step S130, the speed difference is compared with a preset speed difference threshold, and the output torque is compared with a torque threshold to obtain the comparison result.

[0052] It is understandable that the overall logic of comparing the speed difference and output torque in step S130 is that the speed difference should not exceed its own threshold, and the output torque should not exceed the threshold of the torque corresponding to the speed difference. Comparing the two indicators of speed difference and output torque at the same time helps to improve the reliability of the judgment result.

[0053] In this embodiment, a scheme for obtaining comparison results by comparison is also specifically shown. In step S130, a preset safe speed difference is first used as a first speed difference threshold, and a preset limit speed difference is used as a second speed difference threshold, to obtain the following possible comparison results:

[0054] The first speed difference comparison result is that the speed difference is greater than the first speed difference threshold and the speed difference is less than or equal to the second speed difference threshold. The speed difference threshold includes the first speed difference threshold and the second speed difference threshold.

[0055] The second speed difference comparison result shows that the speed difference is greater than the second speed difference threshold.

[0056] The first torque comparison result shows that the output torque is greater than the first torque threshold and the output torque is less than or equal to the second torque threshold.

[0057] The second torque comparison result shows that the output torque is greater than the second torque threshold.

[0058] In the above implementation, the safe speed difference and the limit speed difference are preset for the safe and limit operating conditions corresponding to the speed difference itself. In different implementations, the actual values ​​of the safe speed difference and the limit speed difference also vary depending on the size, mass and material of the differential. Since their specific values ​​are determined during the vehicle design process, they are not limited here. The aforementioned safe torque and limit torque are set based on the torque corresponding to the speed difference, and the evaluation dimensions are different. In this embodiment, the current operating condition is evaluated by the speed difference itself and the torque corresponding to the speed difference, which helps to reduce misjudgment and avoid ineffective limitation on vehicle power.

[0059] Step S140: Determine and implement limiting measures based on the comparison results to limit the initial requested torque.

[0060] Regarding the above steps, it is understood that the evaluation of the operating condition is based on the output torque and speed difference of the current actual operating condition. The output torque is output by the drive motor based on the received torque request. Therefore, after comparing the output torque, it is necessary to limit the initial requested torque to adjust the subsequent output torque. In other words, this method uses the method of limiting the initial requested torque to implement the limiting measures from the input end of the drive motor, through the output torque, and with the speed difference as the final manifestation of the limiting measures. This can limit the speed difference in the most timely manner. At the same time, the limiting of the initial requested torque is not limited to being completed by the vehicle controller. It can be done through an independent calculation unit or control unit, thereby improving the communication delay that may occur when the vehicle controller controls the drive motor through CAN signals in the prior art, and effectively improving the timeliness of differential limiting.

[0061] In this embodiment, based on the aforementioned possible comparison results, an exemplary scheme for determining the limit measures is provided, including the following steps:

[0062] When the comparison result includes one of the first speed difference comparison result, the first torque comparison result, and the second torque comparison result, or when the comparison result includes one of the first torque comparison result, the first speed difference comparison result, and the second speed difference comparison result, the first limit measure shall be implemented, the first limit measure including differential limit protection measures.

[0063] When the comparison results include the second speed difference comparison results and the second torque comparison results, the second limit measures shall be implemented, including shutdown protection measures.

[0064] Report or display the fault information corresponding to the first and second limit measures implemented.

[0065] Regarding the above steps, it is understandable that when both the speed difference and the output torque exceed the range of safe operating conditions, differential limit protection measures need to be taken. By reducing the input torque request, i.e. the initial requested torque, the impact on driving control can be reduced while reducing the output torque and speed difference. When both the speed difference and the output torque exceed the range of extreme operating conditions, shutdown protection measures need to be taken to immediately stop the power output and avoid an accident.

[0066] In the above steps, after the limit measures are taken, the corresponding fault information is reported or displayed. The reporting here includes, but is not limited to, uploading the type of limit measures taken to the vehicle controller, cloud, server or other devices that can be used to analyze or store the messages in the form of a message. The display here includes, but is not limited to, informing or notifying the action of taking limit measures through the vehicle screen, audio, mobile phone or other electronic devices.

[0067] Based on the above implementation methods, this embodiment also exemplarily illustrates specific schemes for the first and second limit measures, wherein the first limit measure is implemented through the following steps:

[0068] The initial requested torque is subjected to torque limit processing with a first torque gradient to obtain a first intermediate requested torque. The first torque gradient represents the torque change gradient per unit time in the torque limit processing, and the first torque gradient is less than or equal to a preset torque reduction gradient.

[0069] Send a torque limiting information acquisition request to the vehicle's traction control system, and obtain the second intermediate requested torque based on the feedback information;

[0070] The minimum effective value between the first intermediate requested torque and the second intermediate requested torque at each moment is taken as the target requested torque input to the drive motor at that moment.

[0071] Report or display differential limit fault information.

[0072] Regarding the execution steps of the aforementioned first limit measure, it should be understood that when the first limit measure is taken, it indicates that the speed difference and the output torque of the drive motor exceed the range of safe operating conditions. It is necessary to perform torque limit processing on the initial requested torque, that is, only a portion of it is actually input to the drive motor to gradually reduce the output torque, thereby reducing the speed difference. For example, in some embodiments, a coefficient is multiplied on the initial requested torque. This coefficient is reduced from 1 to 0, so that the first intermediate requested torque that can actually be input to the drive motor is decreasing relative to the initial requested torque with a first torque gradient until it decreases to 0. At this point, the drive motor can no longer receive the input request and no longer output torque. In this embodiment, the first torque gradient is used as the change gradient of the initial requested torque. The first torque gradient should be less than the preset torque reduction gradient to prevent the risk of operation delay, hardware wear, etc. caused by excessively rapid torque reduction.

[0073] Meanwhile, this embodiment also includes a second intermediate requested torque, which is the requested torque fed back to the drive motor by the traction control system (TCS) based on the vehicle's driving state. The traction control system mainly determines whether the current vehicle driving state is normal by monitoring the wheel movement state and the output torque of the drive motor, thereby controlling the output torque. Its working principle belongs to the prior art and is widely used in this technical field, so it will not be described in detail here.

[0074] By using the minimum effective value of the first intermediate requested torque and the second intermediate requested torque as the target requested torque, it can be ensured that the target requested torque actually input to the drive motor simultaneously meets the torque limit requirements of the drive motor represented by the first intermediate requested torque and the second intermediate requested torque. Here, the effective value refers to the effective requested torque. In some embodiments, the vehicle is not equipped with a traction control system, so it is impossible to obtain the effective second intermediate requested torque fed back by it. In this case, the first intermediate requested torque is used as the target requested torque.

[0075] By taking the above steps and combining them with the traction control system to limit the output torque, the speed difference can be limited, which further improves the accuracy of judging the limit requirements and helps to improve the timeliness of speed difference control.

[0076] In this embodiment, the second limit measure is implemented through the following steps:

[0077] Reset the initial requested torque to zero;

[0078] Report or display downtime fault information.

[0079] Understandably, when the second limit measure is implemented, it indicates that the operating conditions reflected by the speed difference and output torque have exceeded the limit conditions. Therefore, it is necessary to immediately limit the power and stop inputting torque to the drive motor. Thus, the initial requested torque is reset to zero.

[0080] In this embodiment, after determining and implementing the quota measures based on the comparison results, the method further includes the following steps:

[0081] When the speed difference is less than or equal to the preset third speed difference threshold, the limit measure is lifted by the second torque gradient, wherein the second torque gradient represents the torque change gradient per unit time when the limit measure is lifted, the third speed difference threshold is less than the first speed difference threshold, and the second torque gradient is less than or equal to the preset torque increase gradient.

[0082] If the speed difference fails to be acquired, the output torque is limited so that the output torque is less than or equal to the preset third torque threshold.

[0083] Regarding the above steps, it is understood that when the speed difference has been limited to a range that will not cause safety risks after the aforementioned steps, the limiting measures can be terminated. At the same time, in order to avoid repeated triggering of the limiting measures, the third speed difference threshold used to determine whether the limiting measures have been triggered is set to be less than the first speed difference threshold. In order to avoid transmission lag, hardware stress concentration and other possible risks caused by excessively rapid torque increase, it is necessary to ensure that the recovery speed of the output torque does not exceed the preset torque increase gradient.

[0084] In addition, when the speed difference acquisition fails, for example, if the signal feedback from the speed sensor of one or more wheels of the left and right wheels is lost, or if the wheel speed obtained by other means is invalid or lost, the basic steps of this method are missing. In order to avoid the inability to limit the speed difference in time, the output torque is limited so that the output torque is less than or equal to a preset third torque threshold. The third torque threshold can be set as needed according to the differences in the understanding of safe driving and the formulation of design standards in the actual vehicle design process, and is not limited here. In some embodiments, when the output torque is limited by the third torque threshold, the wheel speed signal failure will also be reported or displayed at the same time to inform the user or third party that the wheel speed acquisition function of the current vehicle has failed.

[0085] As described above, the differential speed limiting method based on a motor provided in this application first obtains the initial requested torque input to the drive motor, the output torque of the drive motor, the speed difference of the drive wheels, and preset calibration torque information. Based on the speed difference and calibration torque information, a torque threshold corresponding to the speed difference is determined. Then, the speed difference is compared with the preset speed difference threshold, and the output torque is compared with the torque threshold to obtain the comparison result. Finally, based on the comparison result, a limiting measure is determined and executed to limit the initial requested torque. By jointly determining the differential speed limiting requirement through the speed difference and output torque, the matching degree between the limiting measure and the actual working condition can be effectively improved. By limiting the initial requested torque, control delay can be reduced, effectively improving the timeliness, accuracy, and safety of the differential speed limiting measure, and greatly reducing the control delay and hardware failure risk in the differential speed limiting process.

[0086] In one embodiment, this application also specifically provides a motor-based differential speed limiting device, which corresponds one-to-one with the motor-based differential speed limiting method in the above embodiments, such as... Figure 3 As shown, Figure 3 This is a schematic diagram of the structure of a motor-based differential speed limiting device illustrated in an exemplary embodiment of this application, including a data acquisition module 301, a data processing module 302, a parameter comparison module 303, and an execution module 304. Detailed descriptions of each module are as follows:

[0087] The data acquisition module 301 is used to acquire the initial requested torque input to the drive motor, the output torque of the drive motor, the speed difference of the drive wheels, and the preset calibration torque information.

[0088] Data processing module 302 is used to determine the torque threshold corresponding to the speed difference based on the speed difference and the calibrated torque information;

[0089] The parameter comparison module 303 is used to compare the speed difference with a preset speed difference threshold and the output torque with a torque threshold to obtain the comparison result.

[0090] Execution module 304 is used to determine and execute limiting measures based on the comparison results to limit the torque of the initial request.

[0091] This application provides a motor-based differential speed limiting device. First, it acquires the initial requested torque input to the drive motor, the output torque of the drive motor, the speed difference between the drive wheels, and preset calibration torque information. Based on the speed difference and calibration torque information, it determines the torque threshold corresponding to the speed difference. Then, it compares the speed difference with the preset speed difference threshold and the output torque with the torque threshold to obtain the comparison result. Finally, based on the comparison result, it determines and executes a limiting measure to limit the initial requested torque. By jointly determining the differential speed limiting requirement through the speed difference and output torque, it can effectively improve the matching degree between the limiting measures and the actual working conditions. By limiting the initial requested torque, it can reduce control delay, effectively improve the timeliness, accuracy, and safety of the differential speed limiting measures, and greatly reduce the control delay and hardware failure risk in the differential speed limiting process.

[0092] It should be noted that the motor-based differential speed limiting device and the motor-based differential speed limiting method provided in the above embodiments belong to the same concept. The specific methods by which each terminal performs operations have been described in detail in the method embodiments and will not be repeated here. In practical applications, the motor-based differential speed limiting device provided in the above embodiments can allocate the above functions to different functional modules as needed, that is, divide the internal structure of the system into different functional modules to complete all or part of the functions described above. This is not a limitation here.

[0093] An embodiment of this application also provides an electronic device, including: one or more processors; and a storage device for storing one or more programs, which, when executed by the one or more processors, cause the electronic device to implement the motor-based differential speed limiting method provided in the above embodiments.

[0094] Figure 4 A schematic diagram of a computer system suitable for implementing the embodiments of this application is shown. It should be noted that... Figure 4 The computer system 400 of the electronic device shown is merely an example and should not impose any limitation on the functionality and scope of use of the embodiments of this application.

[0095] like Figure 4As shown, the computer system 400 includes a Central Processing Unit (CPU) 401, which can perform various appropriate actions and processes based on programs stored in Read-Only Memory (ROM) 402 or programs loaded from storage portion 408 into Random Access Memory (RAM) 403, such as performing the methods described in the above embodiments. The RAM 403 also stores various programs and data required for system operation. The CPU 401, ROM 402, and RAM 403 are interconnected via a bus 404. An Input / Output (I / O) interface 405 is also connected to the bus 404.

[0096] The following components are connected to I / O interface 405: an input section 406 including a keyboard, mouse, etc.; an output section 407 including a cathode ray tube (CRT), liquid crystal display (LCD), etc., and speakers, etc.; a storage section 408 including a hard disk, etc.; and a communication section 409 including a network interface card such as a LAN (Local Area Network) card, modem, etc. The communication section 409 performs communication processing via a network such as the Internet. A drive 410 is also connected to I / O interface 405 as needed. A removable medium 411, such as a disk, optical disk, magneto-optical disk, semiconductor memory, etc., is installed on drive 410 as needed so that computer programs read from it can be installed into storage section 408 as needed.

[0097] Specifically, according to embodiments of this application, the processes described above with reference to the flowcharts can be implemented as computer software programs. For example, embodiments of this application include a computer program product comprising a computer program carried on a computer-readable medium, the computer program including a computer program for performing the methods shown in the flowcharts. In such embodiments, the computer program can be downloaded and installed from a network via communication section 409, and / or installed from removable medium 411. When the computer program is executed by central processing unit (CPU) 401, it performs various functions defined in the system of this application.

[0098] It should be noted that the computer-readable medium shown in the embodiments of this application can be a computer-readable signal medium or a computer-readable storage medium, or any combination of the two. A computer-readable storage medium can be, for example, an electrical, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or any combination thereof. More specific examples of a computer-readable storage medium may include, but are not limited to: an electrical connection having one or more wires, a portable computer disk, a hard disk, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM), flash memory, optical fiber, portable compact disc read-only memory (CD-ROM), optical storage device, magnetic storage device, or any suitable combination thereof. In this application, a computer-readable signal medium may include a data signal propagated in baseband or as part of a carrier wave, carrying a computer-readable computer program. Such propagated data signals can take various forms, including but not limited to electromagnetic signals, optical signals, or any suitable combination thereof. Computer-readable signal media can also be any computer-readable medium other than computer-readable storage media, which can send, propagate, or transmit a program for use by or in connection with an instruction execution system, apparatus, or device. The computer program contained on the computer-readable medium can be transmitted using any suitable medium, including but not limited to wireless, wired, etc., or any suitable combination thereof.

[0099] The flowcharts and block diagrams in the accompanying drawings illustrate the architecture, functionality, and operation of possible implementations of systems, methods, and computer program products according to various embodiments of this application. Each block in a flowchart or block diagram may represent a module, segment, or portion of code, which contains one or more executable instructions for implementing a specified logical function. It should also be noted that in some alternative implementations, the functions indicated in the blocks may occur in a different order than those indicated in the drawings. For example, two consecutively indicated blocks may actually be executed substantially in parallel, and they may sometimes be executed in reverse order, depending on the functions involved. It should also be noted that each block in a block diagram or flowchart, and combinations of blocks in a block diagram or flowchart, can be implemented using a dedicated hardware-based system that performs the specified function or operation, or using a combination of dedicated hardware and computer instructions.

[0100] The units described in the embodiments of this application can be implemented in software or hardware, and the described units can also be located in a processor. The names of these units do not necessarily limit the specific unit itself.

[0101] Another aspect of this application provides a computer-readable storage medium storing a computer program thereon, which, when executed by a computer's processor, causes the computer to perform the motor-based differential speed limiting method as described above. This computer-readable storage medium may be included in the electronic device described in the above embodiments, or it may exist independently and not assembled into the electronic device.

[0102] Another aspect of this application provides a computer program product or computer program including computer instructions stored in a computer-readable storage medium. A processor of a computer device reads the computer instructions from the computer-readable storage medium and executes the computer instructions, causing the computer device to perform the motor-based differential speed limiting method provided in the various embodiments described above.

[0103] The above embodiments are merely illustrative of the principles and effects of the present invention and are not intended to limit the invention. Any person skilled in the art can modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by those skilled in the art without departing from the spirit and technical concept disclosed in the present invention should still be covered by the claims of the present invention.

Claims

1. A differential speed limiting method based on a motor, characterized in that, include: The system acquires the initial requested torque input to the drive motor, the output torque of the drive motor, the speed difference of the drive wheels, and preset calibration torque information. Based on the speed difference and the calibrated torque information, determine the torque threshold corresponding to the speed difference; The speed difference is compared with a preset speed difference threshold, and the output torque is compared with the torque threshold to obtain the comparison result; Based on the comparison results, a limiting measure is determined and implemented to limit the initial requested torque. The step of determining the torque threshold corresponding to the speed difference based on the speed difference and the calibrated torque information includes: The calibration torque information includes a safe speed difference-torque graph and a limit speed difference-torque graph. Based on the speed difference, the safe torque and the limit torque corresponding to the speed difference are determined from the safe speed difference-torque graph and the limit speed difference-torque graph, respectively. The safe torque is used as the first torque threshold, and the ultimate torque is used as the second torque threshold. The torque threshold includes the first torque threshold and the second torque threshold. The comparison results include: The preset safe speed difference is used as the first speed difference threshold, and the preset extreme speed difference is used as the second speed difference threshold. The first speed difference comparison result is that the speed difference is greater than the first speed difference threshold and the speed difference is less than or equal to the second speed difference threshold, wherein the speed difference threshold includes the first speed difference threshold and the second speed difference threshold; The second speed difference comparison result is that the speed difference is greater than the second speed difference threshold. The first torque comparison result shows that the output torque is greater than the first torque threshold, and the output torque is less than or equal to the second torque threshold; The second torque comparison result shows that the output torque is greater than the second torque threshold. The step of determining and implementing quota measures based on the comparison results includes: When the comparison result includes one of the first speed difference comparison result, the first torque comparison result, and the second torque comparison result, or when the comparison result includes one of the first torque comparison result, the first speed difference comparison result, and the second speed difference comparison result, a first limit measure is implemented, the first limit measure including differential limit protection measures; When the comparison results include the second speed difference comparison results and the second torque comparison results, the second limit measures are implemented, and the second limit measures include shutdown protection measures; The fault information corresponding to the first and second limit measures implemented shall be reported or displayed.

2. The differential speed limiting method based on a motor according to claim 1, characterized in that, The first limit measure includes: The initial requested torque is subjected to torque limiting processing with a first torque gradient to obtain a first intermediate requested torque. The first torque gradient represents the torque change gradient per unit time in the torque limiting processing, and the first torque gradient is less than or equal to a preset torque reduction gradient. Send a torque limiting information acquisition request to the vehicle's traction control system, and obtain the second intermediate requested torque based on the feedback information; The minimum effective value between the first intermediate requested torque and the second intermediate requested torque at each moment is taken as the target requested torque input to the drive motor at that moment. Report or display differential limit fault information.

3. The differential speed limit method based on a motor according to claim 1, characterized in that, The second limit measure includes: Reset the initial requested torque to zero; Report or display shutdown fault information.

4. The differential speed limiting method based on a motor according to claim 1, characterized in that, After determining and implementing the quota measures based on the comparison results, the method further includes: When the speed difference is less than or equal to a preset third speed difference threshold, the limiting measure is lifted by a second torque gradient, wherein the second torque gradient represents the torque change gradient per unit time when the limiting measure is lifted, the third speed difference threshold is less than the first speed difference threshold, and the second torque gradient is less than or equal to a preset torque increase gradient. If obtaining the speed difference fails, the output torque is limited so that the output torque is less than or equal to a preset third torque threshold.

5. A motor-based differential speed limiting device, used to implement the motor-based differential speed limiting method according to any one of claims 1-4, characterized in that, include: The data acquisition module is used to acquire the initial requested torque input to the drive motor, the output torque of the drive motor, the speed difference of the drive wheels, and preset calibration torque information; The data processing module is used to determine the torque threshold corresponding to the speed difference based on the speed difference and the calibrated torque information; The parameter comparison module is used to compare the speed difference with a preset speed difference threshold and the output torque with the torque threshold to obtain the comparison result. An execution module is used to determine and execute limiting measures based on the comparison results to limit the initial requested torque.

6. An electronic device, characterized in that, The electronic device includes: One or more processors; A storage device for storing one or more programs that, when executed by one or more processors, cause the electronic device to implement the motor-based differential speed limiting method as described in any one of claims 1 to 4.

7. A computer-readable storage medium, characterized in that, It stores a computer program that, when executed by the computer's processor, causes the computer to perform the motor-based differential speed limiting method as described in any one of claims 1 to 4.

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