Motor rotating speed control method and circuit and vehicle

Abstract

The invention discloses a motor rotating speed control method and circuit and a vehicle, and relates to the technical field of vehicles. The method comprises the steps that an initial torque amplitude limiting value is determined based on the current rotating speed of a motor in a vehicle and a rotating speed amplitude limiting value, the rotating speed amplitude limiting value is used for limiting the rotating speed of the motor, and the initial torque amplitude limiting value is used for limiting the torque of the motor; a current torque amplitude limiting value is determined based on the initial torque amplitude limiting value and a torque compensation value, and the torque compensation value is used for counteracting interference of external frictional resistance on the rotating speed of the motor; an output torque instruction is determined based on the indicated torque value and the current torque amplitude limiting value, the indicated torque value is the torque size indicated by the current torque instruction, and the current torque instruction is used for reflecting the current torque intention of the target object; and performing torque control on the motor based on the output torque instruction to adjust the rotating speed of the motor. The technical problem that the response speed and strategy flexibility of a vehicle body stabilizing system in the related technology are insufficient is solved.

Description

Technical Field

[0001] This application relates to the field of vehicle technology, and more specifically, to a method, circuit, and vehicle for controlling motor speed. Background Technology

[0002] Against the backdrop of the rapid development of new energy vehicles, their fast power response and excellent handling have become significant advantages. However, when encountering complex conditions such as rain and snow, speed bumps, or wheels lifting off the ground, effectively preventing slippage, reducing bumps, and avoiding lurching and dizziness become crucial for improving the driving experience and safety.

[0003] Currently, traditional anti-shake and anti-skid technologies rely on Electronic Stability Program (ESP). ESP uses a sensor array to monitor vehicle dynamic parameters in real time, thereby identifying and responding to conditions such as understeer, oversteer, or drive wheel slippage. However, ESP's response speed and strategy flexibility are insufficient, failing to guarantee ideal control performance under all operating conditions.

[0004] There is currently no effective solution to the above problems. Summary of the Invention

[0005] This application provides a motor speed control method, circuit, and vehicle to at least solve the technical problems of insufficient response speed and strategy flexibility in vehicle stability systems in related technologies.

[0006] According to one aspect of the embodiments of this application, a motor speed control method is provided, comprising: determining an initial torque limit value based on the current speed of the motor in a vehicle and a speed limit value, wherein the speed limit value is used to limit the speed of the motor, and the initial torque limit value is used to limit the torque of the motor; determining a current torque limit value based on the initial torque limit value and a torque compensation value, wherein the torque compensation value is used to counteract the interference of external frictional resistance on the motor speed; determining an output torque command based on an indicated torque value and the current torque limit value, wherein the indicated torque value is the torque indicated by the current torque command, and the current torque command is used to reflect the current torque intention of the target object; and performing torque control on the motor based on the output torque command to adjust the motor speed.

[0007] Furthermore, the speed limit value includes a first upper limit value and a first lower limit value. Determining the initial torque limit value based on the current speed of the motor in the vehicle and the speed limit value includes: calculating the difference between the first upper limit value and the current speed to obtain a second upper limit value, and calculating the difference between the first lower limit value and the current speed to obtain a second lower limit value; multiplying the second upper limit value by a proportional coefficient to obtain a third upper limit value, and multiplying the second lower limit value by a proportional coefficient to obtain a third lower limit value; and determining the initial torque limit value based on the third upper limit value and the third lower limit value.

[0008] Further, determining the current torque limit value based on the initial torque limit value and the torque compensation value includes: performing time compensation processing on the torque command of the previous frame to obtain a first torque value, wherein the torque command of the previous frame is the output torque command generated by the motor control system in the frame preceding the current frame; performing error compensation processing on the motor speed of the previous frame to obtain a second torque value, wherein the motor speed of the previous frame is the speed output by the motor in the frame preceding the current frame; calculating the difference between the first torque value and the second torque value to obtain the torque compensation value; and adding the initial torque limit value and the torque compensation value to obtain the current torque limit value.

[0009] Furthermore, the time compensation processing of the previous frame torque command to obtain the first torque value includes: preprocessing the previous frame torque command using a low-pass filter to obtain the processed torque command; and performing time compensation processing on the processed torque command using a torque loop strategy to obtain the first torque value.

[0010] Furthermore, the error compensation processing of the motor speed in the previous frame to obtain the second torque value includes: preprocessing the motor speed in the previous frame using a low-pass filter to obtain the processed motor speed; and performing error compensation processing on the processed torque command using an integral strategy to obtain the second torque value.

[0011] Furthermore, the current torque limit value includes a fourth upper limit value and a fourth lower limit value. Determining the output torque command based on the indicated torque value and the current torque limit value includes: if the indicated torque value is less than the fourth upper limit value and the indicated torque value is greater than the fourth lower limit value, then an output torque command is generated based on the current torque command; or, if the indicated torque value is greater than or equal to the fourth upper limit value, then an output torque command is generated based on the fourth upper limit value; or, if the indicated torque value is less than or equal to the fourth lower limit value, then an output torque command is generated based on the fourth lower limit value.

[0012] Furthermore, the torque control of the motor based on the output torque command to adjust the motor speed includes: using a torque loop strategy to perform time compensation processing on the output torque command to obtain a third torque value; adding the third torque value and the torque interference value to obtain a fourth torque value; and using an integral strategy to perform error compensation processing on the fourth torque value to obtain the output speed of the motor.

[0013] Furthermore, the method also includes: multiplying the output speed and the reduction ratio to obtain the vehicle speed; and controlling the vehicle's driving speed based on the vehicle speed.

[0014] According to another aspect of the embodiments of this application, a motor speed control circuit is also provided, including: a speed monitoring component, a torque limiting component, a saturator, a disturbance observer, and a speed adjustment component; the speed monitoring component is used to determine an initial torque limiting value based on the current speed of the motor in the vehicle and a speed limiting value, wherein the speed limiting value is used to limit the speed of the motor, and the initial torque limiting value is used to limit the torque of the motor; the torque limiting component is used to determine a current torque limiting value based on the initial torque limiting value and a torque compensation value, wherein the torque compensation value is used to offset the interference of external frictional resistance on the motor speed, and the torque compensation value is determined based on the disturbance observer; the saturator is used to determine an output torque command based on an indicated torque value and a current torque limiting value, wherein the indicated torque value is the torque magnitude indicated by the current torque command, and the current torque command is used to reflect the current torque intention of the target object; the speed adjustment component is used to perform torque control on the motor based on the output torque command to adjust the speed of the motor.

[0015] According to another aspect of the embodiments of this application, a vehicle is also provided, including: a memory storing an executable program; and a processor for running the executable program, wherein the executable program performs the methods of various embodiments of this application when running on the processor.

[0016] According to another aspect of the embodiments of this application, a computer-readable storage medium is also provided, the computer-readable storage medium including a stored executable program, wherein, when the executable program is running, it controls the device where the computer-readable storage medium is located to perform the methods of various embodiments of this application.

[0017] According to another aspect of the embodiments of this application, a computer program product is also provided, including a non-volatile computer-readable storage medium storing a computer program that, when executed by a processor, implements the methods in various embodiments of this application.

[0018] According to another aspect of the embodiments of this application, an electronic device is also provided, including a memory and a processor, wherein the memory stores a computer program and the processor is configured to run the computer program to perform the methods in various embodiments of this application.

[0019] In this embodiment, an initial torque limit is determined based on the current motor speed and a speed limit value in the vehicle. The speed limit value restricts the motor's speed, and the initial torque limit value restricts the motor's torque. Then, a current torque limit is determined based on the initial torque limit and a torque compensation value, where the torque compensation value counteracts the interference of external frictional resistance on the motor speed. Next, an output torque command is determined based on an indicated torque value and the current torque limit value, where the indicated torque value is the torque indicated by the current torque command, reflecting the target's current torque intention. Finally, torque control is applied to the motor based on the output torque command to adjust its speed. Therefore, this application can achieve rapid response and smooth control of the motor speed under various complex operating conditions by precisely controlling the motor torque. This optimizes vehicle performance in rain and snow to prevent slippage, reduces bumps when going over speed bumps, and avoids forward lurching and dizziness when the wheels are off the ground. This solves the technical problems of insufficient response speed and strategy flexibility in related vehicle stability systems. Attached Figure Description

[0020] The accompanying drawings, which are included to provide a further understanding of this application and form part of this application, illustrate exemplary embodiments and are used to explain this application, but do not constitute an undue limitation of this application. In the drawings:

[0021] Figure 1 This is a schematic diagram of a motor speed control method according to an embodiment of this application;

[0022] Figure 2 This is a simplified schematic diagram of a vehicle motor according to an embodiment of this application;

[0023] Figure 3 This is a schematic diagram of the working principle of a motor speed control system according to an embodiment of this application;

[0024] Figure 4 This is a schematic diagram illustrating a motor speed control method according to an embodiment of this application;

[0025] Figure 5 This is a schematic diagram illustrating another motor speed control method according to an embodiment of this application;

[0026] Figure 6 This is a schematic diagram of a motor speed control circuit according to an embodiment of this application. Detailed Implementation

[0027] To enable those skilled in the art to better understand the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present application, and not all embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative effort should fall within the scope of protection of the present application.

[0028] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of this application described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0029] First, some nouns or terms that appear in the description of the embodiments of this application shall be interpreted as follows:

[0030] Electronic Stability Program (ESP): An active safety system for automobiles. ESP can detect and reduce the risk of loss of control of the vehicle. By monitoring parameters such as the vehicle's yaw rate, steering angle, wheel speed and lateral acceleration, ESP can automatically brake individual wheels or adjust engine output when the vehicle is understeer or oversteer, in order to help the driver maintain control of the vehicle.

[0031] Low-pass filter: A signal processing tool used to smooth signals and eliminate high-frequency noise or abrupt changes. A low-pass filter only allows signal components with frequencies below a certain threshold to pass through, while suppressing or attenuating signal components with frequencies above this threshold.

[0032] Torque loop strategy: A closed-loop control strategy used to track a reference torque command. By comparing the reference torque command with the actual motor torque output, the control signal (such as the motor voltage or current) is adjusted so that the actual torque output is as close as possible to the command value.

[0033] Integral strategy: In control theory, the integral strategy is the "integral" part of proportional-integral-derivative control (PID control). Its function is to eliminate steady-state error and enable the system output to approach the set value over time.

[0034] Reduction ratio: In a vehicle's transmission system, the ratio between the motor speed and the actual wheel speed is achieved through a gearbox or reducer. The reduction ratio determines the degree to which the motor speed affects the vehicle's speed.

[0035] With the rapid popularization of new energy vehicles, one of their advantages over traditional fuel vehicles is their faster power response and greater potential for improvement in anti-slip and anti-shake performance.

[0036] Currently, the mainstream method for anti-shake and anti-skid in new energy vehicles is to use a vehicle stability system. The vehicle stability system uses a group of sensors such as wheel speed, steering angle, yaw angle, and acceleration to collect vehicle dynamic parameters in real time to identify dangerous conditions such as understeer, oversteer, or drive wheel slippage. Its sampling frequency (e.g., 25Hz) is lower than that of the motor resolver sensor (e.g., 10kHz). Therefore, the vehicle stability system control has a natural disadvantage in response speed compared to direct motor control.

[0037] However, after the vehicle stability system determines that it needs to intervene, it will brake one side of the wheels or limit power output. Because the execution strategy is too simplistic, it cannot guarantee ideal results in all operating conditions and may introduce an unexpected lurch forward, which will spoil the driving experience.

[0038] According to an embodiment of this application, a method for controlling motor speed is provided. It should be noted that the steps shown in the flowchart in the accompanying drawings can be executed in a computer system such as a set of computer-executable instructions. Also, although a logical order is shown in the flowchart, in some cases, the steps shown or described may be executed in a different order than that shown here.

[0039] This application provides a motor speed control method. The motor speed control method can be used to provide motor speed control functionality for preset application scenarios. These preset application scenarios may include the following scenarios in the vehicle field: autonomous driving scenarios for commuting, artificial intelligence (AI) assisted driving scenarios for family cars, automatic parking assistance (APA) scenarios (such as memory parking for self-owned parking spaces in garages, intelligent parking for designated parking spaces in parking lots, etc.), and navigation-guided pilot (NGP) scenarios in urban or highway areas. Furthermore, the preset application scenarios may also include, but are not limited to: motor speed control scenarios for intelligent driving trucks or unmanned trucks in the logistics and transportation field, motor speed control scenarios for autonomous agricultural vehicles in the agricultural machinery field, motor speed control scenarios for unmanned aerial vehicles (UAVs), and motor speed control scenarios for intelligent robots (such as cleaning robots, service robots, delivery robots, etc.).

[0040] When the aforementioned preset application scenario is a scenario in a field other than the vehicle field, those skilled in the art should understand that the vehicle in the above motor speed control method can be replaced with other objects (such as agricultural machinery, drones, robots, etc.). Based on this, this application embodiment takes the vehicle technology field as an example to illustrate the specific implementation of the above motor speed control method.

[0041] Figure 1 This is a schematic diagram of a motor speed control method according to an embodiment of this application, as shown below. Figure 1 As shown, the method includes the following steps:

[0042] Step S10: Determine the initial torque limit value based on the current speed of the motor in the vehicle and the speed limit value, wherein the speed limit value is used to limit the speed of the motor and the initial torque limit value is used to limit the torque of the motor.

[0043] In this embodiment of the application, the speed limit value can be understood as the upper and lower limits of the motor speed that are preset. The speed limit value is used to prevent the motor speed from exceeding the safe or expected range and to avoid phenomena such as slippage and bumps.

[0044] Current speed refers to the actual speed at which the motor in the vehicle is running.

[0045] The initial torque limit is used to restrict the magnitude of the motor's torque, that is, to limit the motor's torque output and ensure that the speed does not exceed the limit. It should be noted that the initial torque limit is not the final limit value for restricting the motor's torque output, and further adjustments are required afterward.

[0046] This can be understood as follows: the motor speed control system of this application monitors the current speed of the motor in real time, and then determines the initial torque limit value based on the current speed and a preset speed limit value. For example, the torque limit value can be obtained by multiplying the difference between the current speed and the speed limit value by a proportional coefficient. It is understood that if the current speed exceeds the limit value, the initial torque limit value will be used to limit the output torque of the motor, thereby controlling the motor speed.

[0047] Therefore, this application can adjust the torque output of the motor in a timely manner, prevent sudden changes in motor speed, and improve the stability of vehicle driving.

[0048] Step S12: Determine the current torque limit value based on the initial torque limit value and the torque compensation value, wherein the torque compensation value is used to offset the interference of external frictional resistance on the motor speed.

[0049] In this embodiment, the torque compensation value is the torque increment used to offset the effect of external frictional resistance on the motor speed. This application introduces a disturbance observer to determine the torque compensation value, thereby ensuring that the motor can maintain the target speed even in the presence of frictional resistance.

[0050] This can be understood as the motor speed control system of this application adjusting the initial torque limit value based on the torque compensation value to calculate the final actual torque compensation value, i.e., the current torque limit value. For example, the initial torque limit value can be added to the torque compensation value to obtain the current torque limit value.

[0051] Therefore, by adjusting the initial torque limit value by incorporating a torque compensation value and determining the current torque limit value, the motor speed control system of this application can better cope with external interferences such as road friction and wind resistance, ensuring the stability of the motor speed. Even in the presence of external friction interference, the motor's torque output can be appropriately adjusted to maintain the target speed, improving the driving comfort of the vehicle under complex road conditions.

[0052] Step S14: Determine the output torque command based on the indicated torque value and the current torque limit value, wherein the indicated torque value is the torque magnitude indicated by the current torque command, and the current torque command is used to reflect the current torque intention of the target object.

[0053] In this embodiment, the indicated torque value is the torque magnitude indicated by the current torque command, which is a torque command generated based on the driver's operating intention or the requirements of the autonomous vehicle control strategy. That is, the indicated torque value reflects the torque target value required by the driver's operating intention or the autonomous vehicle control strategy. For example, the indicated torque value typically originates from the driver's operation (such as the depth of the accelerator pedal) or the output of the autonomous vehicle control system (such as Electronic Stability Program (ESP) or Adaptive Cruise Control (ACC)).

[0054] The output torque command is the final control signal sent to the motor by the motor control system, used to directly adjust the motor's torque output. By determining the output torque command based on the indicated torque value and the current torque limit value, it is ensured that the motor meets immediate torque requirements without exceeding safety and performance limits.

[0055] This can be understood as follows: the motor speed control system of this application compares the indicated torque value with the current torque limit value to determine the actual torque command that the motor needs to execute, i.e., the output torque command. For example, if the indicated torque value falls within the current torque limit value, the output torque command will be directly equal to the indicated torque value, allowing the motor to output torque according to the indicated torque value. If the indicated torque value exceeds the current torque limit value (whether it is the upper or lower limit), the output torque command will be adjusted to be equal to the upper or lower limit of the current torque limit value to prevent the torque output from exceeding the safety threshold and ensure that the motor operates within a safe and controllable range.

[0056] Therefore, this application ensures that the motor torque output meets the requirements of the driver or vehicle control strategy while not exceeding safety and performance limits, achieving precise control, reducing the risk of vehicle loss of control due to excessive torque, and improving driving safety. Furthermore, the adjustment of the output torque command ensures that the motor torque output remains stable under different road conditions, such as when the wheels are off the ground, avoiding unnecessary forward lurching or dizziness, and greatly improving driving comfort and satisfaction.

[0057] Step S16: Perform torque control on the motor based on the output torque command to adjust the motor speed.

[0058] In this embodiment, the motor speed control system uses the aforementioned determined output torque command to perform torque control on the motor, thereby adjusting the motor speed to ensure that the speed matches the target value. Exemplarily, the control process involves adjusting the motor's current or voltage to achieve precise output of the motor torque, which in turn affects the motor's speed. If the output torque command requires an increase in torque, the motor current is increased accordingly, resulting in greater torque and thus increased speed. If the output torque command requires a decrease in torque, the motor current is reduced, decreasing the motor torque and consequently, the speed.

[0059] Therefore, this application directly controls the motor torque based on the output torque command, reducing intermediate delays and enabling faster motor speed control, thus improving the system's response speed. Furthermore, through precise torque control, this application effectively suppresses speed fluctuations, especially when encountering external disturbances (such as changes in road conditions or wind resistance), maintaining stable motor speed and enhancing vehicle stability. Moreover, the fast and precise speed control of this application significantly improves the driving experience, particularly in driving scenarios requiring rapid response, such as preventing slippage in rain or snow, reducing bumps when going over speed bumps, and preventing a feeling of lurching forward when the wheels are off the ground.

[0060] In summary, this application establishes a torque limiting mechanism based on motor speed feedback. This mechanism not only effectively limits motor speed fluctuations under extreme operating conditions but also improves vehicle safety and comfort in complex road conditions through intelligent torque control. Compared to traditional control strategies, this application offers higher response speed and control precision, better addressing driving scenarios such as preventing slippage in rain and snow, reducing bumps when going over speed bumps, and avoiding lurching and dizziness when the wheels are off the ground. It achieves precise matching of motor torque and speed, significantly improving the performance of new energy vehicles while providing drivers with a smoother and more comfortable driving experience.

[0061] In this embodiment, an initial torque limit is determined based on the current motor speed and a speed limit value in the vehicle. The speed limit value restricts the motor's speed, and the initial torque limit value restricts the motor's torque. Then, a current torque limit is determined based on the initial torque limit and a torque compensation value, where the torque compensation value counteracts the interference of external frictional resistance on the motor speed. Next, an output torque command is determined based on an indicated torque value and the current torque limit value, where the indicated torque value is the torque indicated by the current torque command, reflecting the target's current torque intention. Finally, torque control is applied to the motor based on the output torque command to adjust its speed. Therefore, this application can achieve rapid response and smooth control of the motor speed under various complex operating conditions by precisely controlling the motor torque. This optimizes vehicle performance in rain and snow to prevent slippage, reduces bumps when going over speed bumps, and avoids forward lurching and dizziness when the wheels are off the ground. This solves the technical problems of insufficient response speed and strategy flexibility in related vehicle stability systems.

[0062] In an optional embodiment, the speed limit value includes a first upper limit value and a first lower limit value. In step S10, an initial torque limit value is determined based on the current speed of the motor in the vehicle and the speed limit value, including the following method steps:

[0063] Step S101: Calculate the difference between the first upper limit value and the current speed to obtain the second upper limit value, and calculate the difference between the first lower limit value and the current speed to obtain the second lower limit value.

[0064] Step S102: Multiply the second upper limit value by the scaling factor to obtain the third upper limit value, and multiply the second lower limit value by the scaling factor to obtain the third lower limit value.

[0065] Step S103: Determine the initial torque limit value based on the third upper limit value and the third lower limit value.

[0066] In this embodiment of the application, the speed limit value includes a first upper limit value and a first lower limit value, which are used to limit the maximum and minimum speed of the motor to prevent the speed from exceeding the safe or expected range.

[0067] When determining the initial torque limit based on the current speed of the motor in the vehicle and the speed limit value, the difference between the first upper limit value and the current speed can be calculated to obtain the second upper limit value, and the difference between the first lower limit value and the current speed can be calculated to obtain the second lower limit value. This can be understood as calculating the difference between the speed limit value and the current motor speed; this calculation process essentially assesses whether the motor speed is close to its limit value.

[0068] Then, the second upper limit is multiplied by the proportional coefficient to obtain the third upper limit, and the second lower limit is multiplied by the proportional coefficient to obtain the third lower limit. This can be understood as multiplying the calculated second upper and lower limits by a pre-set proportional coefficient (denoted as Kp) to obtain the third upper and lower limits, respectively. The proportional coefficient is a calibrable coefficient; multiplying by this coefficient aims to convert the speed deviation into a torque limiting value, thereby restricting the range of variation in the motor's torque output.

[0069] Finally, the initial torque limit value is determined based on the third upper limit and the third lower limit. This can be understood as initially determining the initial torque limit value based on the calculated third upper and lower limits. The initial torque limit value sets a new constraint on the motor's torque output, ensuring that the motor's speed does not exceed the safe or expected range due to arbitrary changes in torque.

[0070] In an optional embodiment, in step S12, determining the current torque limit value based on the initial torque limit value and the torque compensation value includes the following method steps:

[0071] Step S121: Perform time compensation processing on the torque command of the previous frame to obtain the first torque value, wherein the torque command of the previous frame is the output torque command generated by the motor control system in the previous frame of the current frame.

[0072] Step S122: Perform error compensation processing on the motor speed of the previous frame to obtain the second torque value, wherein the motor speed of the previous frame is the speed output by the motor in the previous frame of the current frame.

[0073] Step S123: Calculate the difference between the first torque value and the second torque value to obtain the torque compensation value.

[0074] Step S124: Add the initial torque limit value to the torque compensation value to obtain the current torque limit value.

[0075] In this embodiment, when determining the current torque limit value based on the initial torque limit value and the torque compensation value, time compensation processing can be performed on the previous frame torque command to obtain the first torque value. The previous frame torque command is the output torque command generated by the motor control system in the frame preceding the current frame; it can be understood as the output torque command generated by the motor control system in the last time frame before the current time frame.

[0076] This application can be understood as performing time compensation processing on the output torque command of the previous frame to eliminate the influence of control delay on torque output, thereby obtaining a first torque value that is closer to real time.

[0077] Simultaneously, error compensation processing is performed on the motor speed of the previous frame to obtain the second torque value. Here, the motor speed of the previous frame is the speed output by the motor in the frame before the current frame, which can be understood as the actual speed output by the motor in the last time frame before the current time frame.

[0078] This application can be understood as also performing error compensation processing on the motor speed of the previous frame, thereby correcting the torque control deviation caused by measurement error or model error, so that the obtained second torque value is closer to the actual requirement.

[0079] Next, the difference between the first torque value and the second torque value is calculated to obtain the torque compensation value. This can be understood as follows: this application calculates the difference between the first torque value after time compensation processing and the second torque value after error compensation processing; this difference is the torque compensation value. The torque compensation value reflects the gap between the error in the control process and the actual demand, and is an important basis for adjusting the torque limit value in the next step.

[0080] Finally, the initial torque limit value is added to the torque compensation value to obtain the current torque limit value. This can be understood as the application adding the previously obtained torque compensation value to the initial torque limit value to obtain an updated current torque limit value. This ensures that the motor's torque output meets immediate requirements while also being corrected in a timely manner based on errors from the previous control process, thereby achieving a more precise torque control effect.

[0081] As can be seen, this application effectively corrects potential errors during the control process through time compensation and error compensation, enhancing the closed-loop feedback characteristics of torque control and ensuring the stability and accuracy of the control process. Simultaneously, by dynamically calculating and adjusting the torque compensation value, the current torque limit value can more accurately match the actual driving needs of the vehicle, avoiding mismatch between torque output and demand, and improving vehicle driving efficiency and comfort. Furthermore, the introduction of torque compensation increases the system's resistance to various disturbances, improving the overall robustness of the system. Especially when facing complex operating conditions (such as rainy or snowy weather, bumpy roads, etc.), it ensures the stability of motor speed and torque output, avoiding unexpected vehicle behavior and enhancing driving safety.

[0082] In an optional embodiment, in step S121, time compensation processing is performed on the torque command of the previous frame to obtain a first torque value, including the following method steps:

[0083] Step S1211: Use a low-pass filter to preprocess the torque command of the previous frame to obtain the processed torque command.

[0084] Step S1212: The torque command is processed using a torque loop strategy to perform time compensation processing to obtain the first torque value.

[0085] In this embodiment, when performing time compensation processing on the previous frame torque command to obtain the first torque value, a low-pass filter can be used to preprocess the previous frame torque command to obtain the processed torque command. The low-pass filter (denoted as Q, with a cutoff frequency that can be designed to be 50Hz, but not limited here) is used to filter high-frequency noise in the previous frame torque command, improving the accuracy of subsequent calculations.

[0086] This application can be understood as follows: it first uses a low-pass filter to preprocess the torque command from the previous frame, removing any high-frequency noise or abrupt changes to obtain a smoother and more stable torque command. This ensures that the subsequently calculated torque command is more reliable and will not cause control instability due to signal noise.

[0087] Then, a torque loop strategy is used to perform time compensation processing on the torque command to obtain the first torque value. The torque loop strategy (denoted as torque loop G) is then employed. p_1 This is used to perform time compensation on the torque command after the aforementioned steps, that is, to take into account the time delay between the generation of the control signal and its actual impact on the motor output, and to make corresponding corrections to the processed torque command.

[0088] This application can be understood as taking into account the time delay between the generation of the control signal and the motor response, and thus employing a torque loop strategy to perform time compensation processing on the torque command to obtain the first torque value. The goal of the time compensation processing is to make the motor torque control more accurate and timely, and to reduce control errors caused by time delays.

[0089] As can be seen, the preprocessing with a low-pass filter in this application can effectively reduce high-frequency noise in torque commands, avoid unnecessary torque fluctuations, and improve the stability and reliability of the control system. Furthermore, the time compensation processing of the torque loop strategy can reduce the impact of the time delay between the generation of the control signal and the motor output, making the motor response faster and the control more precise.

[0090] In an optional embodiment, in step S122, error compensation processing is performed on the motor speed of the previous frame to obtain the second torque value, including the following method steps:

[0091] Step S1221: Use a low-pass filter to preprocess the motor speed of the previous frame to obtain the processed motor speed.

[0092] Step S1222: An integral strategy is used to perform error compensation processing on the torque command to obtain the second torque value.

[0093] In this embodiment, when performing error compensation processing on the motor speed of the previous frame to obtain the second torque value, a low-pass filter can be used to preprocess the motor speed of the previous frame to obtain the processed motor speed. This can be understood as follows: this application first uses a low-pass filter to preprocess the motor speed of the previous frame to remove high-frequency noise or abrupt changes that may exist in the speed signal, resulting in a smoother and more stable processed motor speed, providing a more accurate data basis for subsequent error analysis.

[0094] Then, an integral strategy is used to perform error compensation processing on the torque command to obtain the second torque value. The integral strategy (denoted as G in the vehicle speed stage) is then employed. p_2 It is used to compensate for the error between the processing motor speed and the target speed. By accumulating the error, the control signal is adjusted to ensure that the motor speed is stable near the target value.

[0095] This application can be understood as employing an integral strategy to compensate for the error between the processed motor speed and the target speed. The integral strategy accumulates the speed deviation, and as the deviation accumulates, the system adjusts the torque output accordingly to reduce the deviation until it is eliminated, thereby obtaining a second torque value. This second torque value is used to guide the motor torque output at the next moment.

[0096] Therefore, the preprocessing of the low-pass filter can reduce high-frequency noise in the motor speed signal, making it smoother and helping to reduce instantaneous fluctuations in control, thus improving the stability and reliability of speed control. Simultaneously, the error compensation processing of the integral strategy can effectively eliminate steady-state errors in motor speed control. Even in the presence of continuous disturbances, it can adjust the torque output by accumulating errors, making the actual speed as close as possible to the target speed. Furthermore, the second torque value obtained through error compensation is the result of dynamically adjusting the torque output based on real-time analysis and historical data, thereby enabling more precise control of the motor speed and improving vehicle driving comfort and safety.

[0097] In an optional embodiment, the current torque limit value includes a fourth upper limit value and a fourth lower limit value. In step S14, the output torque command is determined based on the indicated torque value and the current torque limit value, including the following method steps:

[0098] Step S141: If the indicated torque value is less than the fourth upper limit value and the indicated torque value is greater than the fourth lower limit value, then an output torque command is generated based on the current torque command.

[0099] Alternatively, in step S142, if the indicated torque value is greater than or equal to the fourth upper limit value, an output torque command is generated based on the fourth upper limit value.

[0100] Alternatively, in step S143, if the indicated torque value is less than or equal to the fourth lower limit value, an output torque command is generated based on the fourth lower limit value.

[0101] In this embodiment of the application, when determining the output torque command based on the indicated torque value and the current torque limit value, the output logic is divided into the following three cases:

[0102] Scenario 1: If the indicated torque value is less than the fourth upper limit and greater than the fourth lower limit, then an output torque command is generated based on the current torque command. This can be understood as follows: if the indicated torque value is both less than the upper limit and greater than the lower limit of the current torque limit, it indicates that the indicated torque value is within the safe and performance-permissible range. In this case, the indicated torque value can be directly used as the output torque command without additional adjustments or restrictions, thus ensuring optimal vehicle power performance.

[0103] Scenario 2: If the indicated torque value is less than or equal to the fourth lower limit, the output torque command is generated based on the fourth lower limit. This can be understood as follows: if the indicated torque value exceeds the upper limit of the current torque limit (i.e., greater than or equal to the fourth upper limit), the corresponding output torque command is directly generated using the fourth upper limit. This prevents excessive motor torque output, which could increase safety risks such as tire slippage and vehicle loss of control.

[0104] Scenario 3: If the indicated torque value is less than or equal to the fourth lower limit, then the output torque command is generated based on the fourth lower limit. This can be understood as follows: if the indicated torque value is less than or equal to the fourth lower limit, then the corresponding output torque command is generated based on the fourth lower limit. This avoids excessively low torque output, which could lead to insufficient power or sluggish control response, ensuring that the vehicle maintains basic driving performance and stability even under low torque demand.

[0105] Therefore, through the output logic of the torque command described above in this application, intelligent management and safety control of the motor torque output are achieved, ensuring that the motor torque meets performance requirements without exceeding safety boundaries under various operating conditions. This dynamic adjustment mechanism based on the current torque limit value and the indicated torque value not only improves the flexibility and response speed of motor control, but also enhances the stability and safety of new energy vehicles in complex driving environments, avoiding abnormal vehicle behavior caused by improper torque output, and providing drivers with a safer and smoother driving experience.

[0106] In an optional embodiment, in step S16, torque control of the motor is performed based on the output torque command to adjust the motor speed, including the following method steps:

[0107] Step S161: The torque loop strategy is used to perform time compensation processing on the output torque command to obtain the third torque value.

[0108] Step S162: Add the third torque value and the torque interference value to obtain the fourth torque value.

[0109] Step S163: An integral strategy is used to perform error compensation processing on the fourth torque value to obtain the output speed of the motor.

[0110] In this embodiment, when controlling the motor's speed based on the output torque command, a torque loop strategy can be used to perform time compensation processing on the output torque command to obtain a third torque value. This can be understood as time compensation correcting the time delay between control signal transmission and motor response, ensuring the motor operates at the correct torque value at the correct time, thereby improving the timeliness and accuracy of control.

[0111] Then, the third torque value and the torque interference value are added together to obtain the fourth torque value. The torque interference value (denoted as d) is used to represent the adverse effects of the external environment on the motor's torque output. For example, adverse effects may be wind resistance, road friction, or other interference factors, which are not limited here. It can be understood that this application considers the influence of external environmental factors on torque output, and by increasing the compensation of the torque interference value, ensures that the motor can still output the expected torque and maintain a stable driving state when facing interference such as wind resistance and road friction.

[0112] Finally, an integral strategy is used to compensate for the error in the fourth torque value to obtain the motor's output speed. This can be understood as follows: by accumulating the deviation between the output torque and the fourth torque value, the integral strategy gradually adjusts the motor's output torque, stabilizing the motor's output speed near the target value (i.e., the final output speed of the motor), thereby achieving precise motor speed control.

[0113] Figure 2 This is a simplified schematic diagram of a vehicle motor according to an embodiment of this application, where the motor is denoted as the controlled object G. n Controlled object G n It is a high-order hysteresis element, affected by various torque disturbances d. The controlled object G n The torque ring G plays a dominant role in this process. p_1 and speed integral G p_2 Two steps.

[0114] like Figure 2 As shown, torque ring G p_1 It is a first-order inertial element, torque loop G p_1 The expression is given in formula (1).

[0115]

[0116] Where Trq is the torque ring Gp_1 The time constant is Trq = 1 / (2 × π × 50 Hz) ≈ 0.003 s. s is the complex frequency variable in the Laplace transform. 50 Hz is the torque loop G. p_1 The cutoff frequency, taking into account the dynamic characteristics of components such as the motor and transmission system, is determined by the torque loop G. p_1 The cutoff frequency is designed to be approximately 50Hz, indicating that it can quickly respond to low-frequency torque changes and smooth the motor torque output. It can be adjusted according to actual conditions, and there is no limitation here.

[0117] Speed ​​integral G p_2 It is an integral term, the integral of rotational speed G. p_2 The expression is given in formula (2).

[0118]

[0119] Among them, J m is the moment of inertia of the motor, and s is the complex frequency variable in the Laplace transform.

[0120] Figure 2 It can be seen that the output torque command (denoted as Trqcmd) output by the motor control system will first be input to the torque loop G. p_1 Using torque ring G p_1 The output torque command undergoes time compensation processing to obtain the estimated torque (i.e., the third torque value). Then, the torque disturbances to vehicle torque control caused by external environmental factors, such as wind resistance and road friction (i.e., the torque disturbance value d), are added to the estimated torque via an adder, and the result of the addition (i.e., the fourth torque value) is used as input to the speed integral G. p_2 Using speed integral G p_2 The input is processed to compensate for errors, and the output speed of the motor (denoted as Spd) is obtained.

[0121] Therefore, through G p_1 and G p_2 By combining these features, the system can reduce steady-state errors caused by external disturbances, ensuring that vehicle speed remains stable near the target value even under complex and changing road conditions. Meanwhile, due to G... p_1 Its rapid response characteristics enable the vehicle to quickly adjust torque output to adapt to changes in driver needs or road conditions, improving the vehicle's dynamic performance and driving experience.

[0122] In an optional embodiment, the method further includes the following steps:

[0123] Step S164: Multiply the output speed and the reduction ratio to obtain the vehicle speed.

[0124] Step S165: Control the vehicle's speed based on the vehicle speed.

[0125] In this embodiment, the output speed of the motor (denoted as Spd) is multiplied by the reduction ratio to obtain the vehicle speed. The reduction ratio (denoted as K) is the proportional relationship between the motor speed and the actual wheel speed (i.e., the output speed), used to determine the degree of influence of the motor speed on the vehicle speed. Then, using the calculated vehicle speed, the vehicle speed is further adjusted to ensure that the vehicle speed matches the driver's intentions, road conditions, and safety standards.

[0126] Therefore, by precisely controlling the motor output speed through the solution of this application, and thereby adjusting the vehicle speed, not only can the vehicle operate stably and safely under complex working conditions, but energy utilization efficiency is also optimized and the driving experience is improved.

[0127] Figure 3 This is a schematic diagram of the working principle of a motor speed control system according to an embodiment of this application, such as... Figure 3 As shown, the motor speed control system first compares whether the actual motor speed Spd exceeds the set speed limit range (upper speed limit and lower speed limit), and then outputs the difference between the actual speed Spd and the speed limit range. Next, the difference is multiplied by the proportional coefficient Kp to calculate the initial torque limit value Trq*. Then, the initial torque limit value Trq* is added to the disturbance compensation torque value to obtain the actual torque limit value (upper and lower limits), which will be used to adjust the motor's torque output.

[0128] Next, the actual torque limit value is compared and adjusted with the vehicle torque command u, and the final adjusted torque command y is output. The torque command y will be used to control the torque output of the motor, thereby indirectly controlling the vehicle speed and ensuring that it does not exceed the preset safety range.

[0129] Afterwards, the controlled subject G n The system receives torque commands y (Trqcmd) and various torque disturbances d during actual driving, such as wind resistance, changes in road conditions, and vehicle load. Then, the controlled object G... n Under the torque command y, the actual vehicle speed Spd is output after overcoming various disturbances. The actual speed Spd is multiplied by the vehicle reduction ratio K to convert the motor speed into the actual vehicle speed, thereby adjusting the vehicle's speed. Simultaneously, the actual speed Spd is also fed back into the aforementioned process and added to the initial torque limit value Trq*.

[0130] Furthermore, the torque command y is also input to the low-pass filter Q and the torque loop G. p_1 In the process, the torque command y passes through the low-pass filter Q and the torque loop G. p_1The inertial processing first eliminates high-frequency components in the torque command through a low-pass filter Q, retaining only the low-frequency torque signal closely related to the vehicle's driving state. This signal is then further input into the first-order inertial torque loop G. p_1 Time compensation processing is performed, and a final estimated torque is output. Simultaneously, the actual engine speed Spd is also input to the low-pass filter Q and the speed integral G. p_2 First, a low-pass filter Q is used to filter out high-frequency noise and rapidly changing interference, retaining only the low-frequency speed information that reflects the actual driving conditions of the vehicle. This information is then further input to the speed integral G. p_2 The process involves integration, ultimately outputting a torque calculated based on acceleration. Finally, the torque difference between the estimated torque and the calculated torque is calculated to obtain the disturbance compensation torque value, which is fed back into the aforementioned process for comparison with the speed limit range.

[0131] Figure 4 This is a schematic diagram illustrating a motor speed control method according to an embodiment of this application, as shown below. Figure 4 As shown, when the torque indicated by the vehicle torque command u (i.e., the indicated torque value) is within the current torque limit range (i.e., the indicated torque value is less than the upper limit of the current torque limit and greater than the lower limit of the current torque limit), the vehicle torque command u normally acts on the controlled object G. n Torque ring G p_1 Above, it is not affected by the speed limit. That is, the vehicle torque command u is directly used as the output torque command y of the motor control system.

[0132] Figure 5 This is a schematic diagram illustrating another motor speed control method according to an embodiment of this application, as shown below. Figure 5 As shown, when the torque indicated by the vehicle torque command u (i.e., the indicated torque value) is not within the current torque limit range (i.e., the indicated torque value is greater than or equal to the fourth upper limit value, or the indicated torque value is less than or equal to the fourth lower limit value), the upper and lower torque limits take effect. Specifically, if the torque indicated by the vehicle torque command u is greater than or equal to the upper limit value within the current torque limit range, a corresponding output torque command is generated based on that upper limit value. If the torque indicated by the vehicle torque command u is less than or equal to the lower limit value within the current torque limit range, a corresponding output torque command is generated based on that lower limit value.

[0133] Furthermore, when the upper and lower torque limits are in effect, the transfer function G between the torque limit Trq* and the speed Spd is... Trq*_Spd As shown in formula (3). G Trq*_Spd This demonstrates how the torque limit value Trq* affects the dynamic response of the motor speed Spd after disturbance compensation, filtering, and smoothing control.

[0134]

[0135] Among them, G n It describes the ability and characteristics of the controlled object to receive input signals (such as torque) and generate corresponding outputs (such as rotational speed). G p_2 Q is the transfer function for the speed integral term, responsible for the dynamic response that converts torque or acceleration signals into speed or speed feedback signals. G is the transfer function for the low-pass filter. p_1 Let Q·G be the transfer function of the control element in the torque loop. p_1 Indicate Q and G p_1 The product of reflects the system's resistance to disturbances at low frequencies and its suppression effect at high frequencies.

[0136] When Q·G p_1 ≈1, meaning that when the frequency is below 50Hz, the transfer function G between the torque limit Trq* and the speed Spd is approximately 1. Trq*_Spd It can be simplified to formula (4).

[0137]

[0138] When Q≈0, i.e., the frequency is higher than 50Hz, the transfer function G between torque limit Trq* and speed Spd is... Trq*_Spd It can be simplified to formula (5).

[0139] G Trq*_Spd =G n Formula (5)

[0140] It can be seen that at low frequencies, i.e., frequencies less than 50Hz, the controlled object G... n Equivalent to an integral step G p_2 and first-order inertial element G p_1 Combination (G) p_2 ·G p_1 The bandwidth of the entire system is the same as that of the controller during design, which is the ideal state for controller design because the system bandwidth and response characteristics are easier to control, which is conducive to achieving precise speed adjustment.

[0141] At high frequencies, i.e., frequencies greater than 50Hz, the controlled object G n This is equivalent to a higher-order lag element, with the system response primarily determined by the controlled object G. n The natural dynamic characteristics of a motor mean that the controller's ability to suppress high-frequency noise is weakened, but noise above 50Hz is usually not a major influencing factor.

[0142] When the upper and lower torque limits are in effect, the transfer function G between the torque disturbance d and the speed Spd is... d_Spd This can be represented by formula (6). G d_SpdThe paper presents the control process of how torque disturbance d affects motor speed Spd at different frequencies, and how the system responds to these disturbances through disturbance observation, filtering and smooth control mechanisms to ensure the stability and comfort of vehicle operation.

[0143]

[0144] When Q·G p_1 ≈1, meaning that when the frequency is below 50Hz, the transfer function G of torque disturbance d and rotational speed Spd is approximately equal to 1. d_Spd It can be simplified to 0.

[0145] When Q≈0, i.e., the frequency is higher than 50Hz, the transfer function G of torque disturbance d and speed Spd is... d_Spd It can be simplified to formula (7).

[0146] G d_Spd =G p_2 Formula (7)

[0147] It can be seen that at low frequencies, i.e., frequencies less than 50Hz, the torque disturbance d has zero effect on the rotational speed Spd, because the low-pass filter Q and the first-order inertial element G... p_1 The combination of these can effectively suppress these torque disturbances.

[0148] At high frequencies, i.e., frequencies greater than 50Hz, the torque disturbance d normally acts on the speed integral term G. p_2 The above means that the torque disturbance d is mainly transmitted through the speed integral term G. p_2 Spd affects the motor speed.

[0149] In summary, this application proposes a torque control algorithm for stable engine speed. Its main principle is to switch the torque command to a speed limit value when the actual engine speed exceeds the speed limit range. The torque limit value is obtained by multiplying the difference between the speed limit value and the actual engine speed by a proportional coefficient, and then limiting the engine speed by limiting the torque. Furthermore, to address the impact of wind resistance, road friction, and other interference factors on the control effect during vehicle operation, this application incorporates a disturbance observer into the torque control, thereby offsetting the influence of frictional resistance interference and ensuring that the designed system bandwidth does not change with road conditions or vehicle speed. Therefore, this application achieves optimizations in several aspects, including preventing slippage in rain and snow, reducing bumps when going over speed bumps and manhole covers, and avoiding dizziness caused by wheel lift. Compared with traditional vehicle stability systems, it has the advantages of fast response and small speed fluctuations.

[0150] It is understood that the proposed solution can further incorporate integral and derivative control on top of proportional control, thereby reducing steady-state error and overshoot. Furthermore, although this solution is based on vehicle control, it can also be applied to other control applications such as temperature control, current control, voltage control, position control, and flow control, without limitation.

[0151] It should be noted that the user information (including but not limited to user device information, user personal information, etc.) and data (including but not limited to data used for analysis, data stored, data displayed, etc.) involved in this application are all information and data authorized by the user or fully authorized by all parties. Furthermore, the collection, use and processing of the relevant data must comply with the relevant laws, regulations and standards of the relevant countries and regions, and corresponding operation portals are provided for users to choose to authorize or refuse.

[0152] According to an embodiment of this application, a circuit embodiment for motor speed control is provided. It should be noted that the motor speed control circuit can be used to execute the above-described motor speed control method.

[0153] Figure 6 This is a schematic diagram of a motor speed control circuit according to an embodiment of this application, as shown below. Figure 6 As shown, the motor speed control circuit includes: a speed monitoring component, a torque limiting component, a saturator, a disturbance observer, and a speed adjustment component.

[0154] The speed monitoring component is used to determine the initial torque limit value based on the current speed of the motor in the vehicle and the speed limit value. The speed limit value is used to limit the speed of the motor, and the initial torque limit value is used to limit the torque of the motor.

[0155] The torque limiting component is used to determine the current torque limiting value based on the initial torque limiting value and the torque compensation value. The torque compensation value is used to offset the interference of external frictional resistance on the motor speed and is determined based on the disturbance observer.

[0156] A saturator is used to determine the output torque command based on the indicated torque value and the current torque limit value, where the indicated torque value is the torque magnitude indicated by the current torque command, which reflects the current torque intention of the target object.

[0157] The speed adjustment component is used to control the torque of the motor based on the output torque command in order to adjust the motor speed.

[0158] In this embodiment, the motor speed control circuit includes: a speed monitoring component, a torque limiting component, a saturator, a disturbance observer, and a speed adjustment component. The motor speed control circuit is capable of executing the motor speed control method described in the foregoing embodiments; please refer to the description of the foregoing embodiments for details, which will not be repeated here.

[0159] Embodiments of this application also provide a vehicle, including: a memory storing an executable program; and a processor for running the executable program, wherein the executable program performs the methods of various embodiments of this application when running on the processor.

[0160] Embodiments of this application also provide a computer-readable storage medium including a stored executable program, wherein, when the executable program is running, it controls the device where the computer-readable storage medium is located to perform the methods of various embodiments of this application.

[0161] Embodiments of this application also provide a computer program product, including a non-volatile computer-readable storage medium for storing a computer program that, when executed by a processor, implements the methods in various embodiments of this application.

[0162] Embodiments of this application also provide an electronic device including a memory and a processor, wherein the memory stores a computer program and the processor is configured to run the computer program to perform the methods in various embodiments of this application.

[0163] In the above embodiments of this application, the descriptions of each embodiment have different focuses. For parts not described in detail in a certain embodiment, please refer to the relevant descriptions of other embodiments.

[0164] In the several embodiments provided in this application, it should be understood that the disclosed technical content can be implemented in other ways. The device embodiments described above are merely illustrative; for example, the division of units can be a logical functional division, and in actual implementation, there may be other division methods. For instance, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the displayed or discussed mutual coupling, direct coupling, or communication connection may be through some interfaces; the indirect coupling or communication connection between units or modules may be electrical or other forms.

[0165] 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 units. Some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs.

[0166] 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.

[0167] 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 described in the various embodiments of this application. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, read-only memory (ROM), random access memory (RAM), portable hard drives, magnetic disks, or optical disks.

[0168] The above description is only a preferred embodiment of this application. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of this application, and these improvements and modifications should also be considered within the scope of protection of this application.

Claims

1. A method for controlling motor speed, characterized in that, The method includes: An initial torque limit value is determined based on the current speed of the motor in the vehicle and the speed limit value, wherein the speed limit value is used to limit the speed of the motor, and the initial torque limit value is used to limit the torque of the motor. The current torque limit value is determined based on the initial torque limit value and the torque compensation value, wherein the torque compensation value is used to offset the interference of external frictional resistance on the motor speed; The output torque command is determined based on the indicated torque value and the current torque limit value, wherein the indicated torque value is the torque magnitude indicated by the current torque command, and the current torque command is used to reflect the current torque intention of the target object; The motor is subjected to torque control based on the output torque command to adjust the motor speed.

2. The method according to claim 1, characterized in that, The speed limit value includes a first upper limit value and a first lower limit value, and the determination of the initial torque limit value based on the current speed of the motor in the vehicle and the speed limit value includes: Calculate the difference between the first upper limit value and the current rotational speed to obtain the second upper limit value, and calculate the difference between the first lower limit value and the current rotational speed to obtain the second lower limit value; Multiply the second upper limit value by the scaling factor to obtain the third upper limit value, and multiply the second lower limit value by the scaling factor to obtain the third lower limit value; The initial torque limit value is determined based on the third upper limit value and the third lower limit value.

3. The method according to claim 1, characterized in that, Determining the current torque limit value based on the initial torque limit value and the torque compensation value includes: Time compensation processing is performed on the torque command of the previous frame to obtain the first torque value, wherein the torque command of the previous frame is the output torque command generated by the motor control system in the frame preceding the current frame; Error compensation processing is performed on the motor speed of the previous frame to obtain the second torque value, wherein the motor speed of the previous frame is the speed output by the motor in the previous frame of the current frame; The difference between the first torque value and the second torque value is calculated to obtain the torque compensation value; The initial torque limit value is added to the torque compensation value to obtain the current torque limit value.

4. The method according to claim 3, characterized in that, The step of performing time compensation processing on the torque command of the previous frame to obtain the first torque value includes: The torque command of the previous frame is preprocessed using a low-pass filter to obtain the processed torque command; The torque command is processed using a torque loop strategy to perform time compensation processing, thereby obtaining the first torque value.

5. The method according to claim 3, characterized in that, The step of performing error compensation processing on the motor speed of the previous frame to obtain the second torque value includes: The motor speed of the previous frame is preprocessed using a low-pass filter to obtain the processed motor speed; An integral strategy is used to perform error compensation processing on the torque command to obtain the second torque value.

6. The method according to claim 1, characterized in that, The current torque limit value includes a fourth upper limit value and a fourth lower limit value, and the determination of the output torque command based on the indicated torque value and the current torque limit value includes: If the indicated torque value is less than the fourth upper limit value and the indicated torque value is greater than the fourth lower limit value, then the output torque command is generated based on the current torque command; or, If the indicated torque value is greater than or equal to the fourth upper limit value, then the output torque command is generated based on the fourth upper limit value; or, If the indicated torque value is less than or equal to the fourth lower limit value, then the output torque command is generated based on the fourth lower limit value.

7. The method according to any one of claims 1-6, characterized in that, The step of controlling the motor's torque based on the output torque command to adjust the motor's speed includes: A torque loop strategy is used to perform time compensation processing on the output torque command to obtain a third torque value; The third torque value and the torque interference value are added together to obtain the fourth torque value; An integral strategy is used to perform error compensation processing on the fourth torque value to obtain the output speed of the motor.

8. The method according to claim 7, characterized in that, The method further includes: Multiplying the output speed and the reduction ratio, the vehicle speed is obtained. The vehicle's speed is controlled based on the vehicle speed.

9. A motor speed control circuit, characterized in that, The circuit includes: a speed monitoring component, a torque limiting component, a saturator, a disturbance observer, and a speed adjustment component; the speed monitoring component is used to determine an initial torque limiting value based on the current speed of the motor in the vehicle and a speed limiting value, wherein the speed limiting value is used to limit the speed of the motor, and the initial torque limiting value is used to limit the torque of the motor; the torque limiting component is used to determine a current torque limiting value based on the initial torque limiting value and a torque compensation value, wherein the torque compensation value is used to offset the interference of external frictional resistance on the motor speed, and the torque compensation value is determined based on the disturbance observer; the saturator is used to determine an output torque command based on an indicated torque value and the current torque limiting value, wherein the indicated torque value is the torque magnitude indicated by the current torque command, and the current torque command is used to reflect the current torque intention of the target object; the speed adjustment component is used to perform torque control on the motor based on the output torque command to adjust the speed of the motor.

10. A vehicle, characterized in that, include: Memory, which stores executable programs; A processor for running the executable program, wherein the executable program, when running on the processor, performs the motor speed control method according to any one of claims 1 to 8.

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