Automobile torque control method and device, vehicle controller and storage medium

Abstract

The application relates to an automobile torque control method and device, a vehicle controller and a storage medium. The method comprises the following steps: during automobile parking braking, if a comfortable braking function flag bit of the automobile in a current parking braking period is in an activated state, the motor speed of the automobile is acquired; according to the motor speed and the automobile braking torque, the feedforward torque of the automobile is acquired; according to the motor speed, the target deceleration of the automobile is acquired, and the feedback torque of the automobile is obtained by using the target deceleration and the actual deceleration of the automobile; according to the feedforward torque, the feedback torque and the braking torque, the target torque of the automobile is acquired, and the torque control instruction of the automobile in the current parking braking period is generated according to the target torque; the torque control instruction is used for adjusting the motor torque output of the automobile to the target torque, so as to control the parking braking of the automobile. The automobile torque control precision can be improved by adopting the method.

Description

Technical Field

[0001] This application relates to the field of automotive control technology, and in particular to an automotive torque control method, device, vehicle controller, storage medium, and computer program product. Background Technology

[0002] With the development of automotive control technology, a technology has emerged that introduces driving torque during parking to achieve comfortable braking. This technology can introduce driving torque during parking, thereby reducing the rate of change of vehicle deceleration during parking braking, thus reducing the pitching sensation of the vehicle during parking and improving the driver's driving experience.

[0003] However, if the output control of the drive torque is not reasonable, it may lead to an unreasonable deceleration setting, resulting in the inability to suppress vehicle pitch, or insufficient deceleration, or even acceleration. It can be seen that the existing vehicle torque control methods have low accuracy. Summary of the Invention

[0004] Therefore, it is necessary to provide an automotive torque control method, device, vehicle controller, computer-readable storage medium, and computer program product that can improve the accuracy of automotive torque control in response to the above-mentioned technical problems.

[0005] In a first aspect, this application provides a method for controlling automotive torque, including:

[0006] During vehicle parking braking, if the comfort braking function flag of the vehicle is activated during the current parking braking cycle, the motor speed of the vehicle during the current parking braking cycle is obtained.

[0007] Based on the motor speed and the vehicle's braking torque in the current parking braking cycle, the feedforward torque of the vehicle in the current parking braking cycle is obtained;

[0008] Based on the motor speed, the target deceleration of the vehicle in the current parking braking cycle is obtained, and the feedback torque of the vehicle in the current parking braking cycle is obtained using the target deceleration and the actual deceleration of the vehicle in the current parking braking cycle.

[0009] Based on the feedforward torque, the feedback torque, and the braking torque, the target torque of the vehicle in the current parking braking cycle is obtained, and a torque control command for the vehicle in the current parking braking cycle is generated based on the target torque; the torque control command is used to adjust the motor torque output of the vehicle to the target torque to control the parking braking of the vehicle.

[0010] In one embodiment, obtaining the target deceleration of the vehicle in the current parking braking cycle based on the motor speed includes: obtaining a reference target deceleration that matches the motor speed from a pre-constructed first mapping relationship; the first mapping relationship stores the correspondence between different motor speeds and different reference target decelerations; wherein the magnitude of the reference target deceleration is positively correlated with the motor speed; and obtaining the target deceleration of the vehicle in the current parking braking cycle based on the reference target deceleration.

[0011] In one embodiment, obtaining the target deceleration of the vehicle in the current parking braking cycle based on the benchmark target deceleration includes: obtaining a target deceleration correction coefficient for the vehicle corresponding to the current parking braking process; the target deceleration correction coefficient is obtained based on the historical parking braking behavior of the vehicle corresponding to the comfort braking function flag being in an active state during historical parking braking processes; and correcting the benchmark target deceleration using the target deceleration correction coefficient to obtain the target deceleration of the vehicle in the current parking braking cycle.

[0012] In one embodiment, obtaining the target deceleration correction coefficient for the current vehicle parking braking process includes: obtaining the number of times the comfort braking function flag is activated during the historical parking braking process; the first historical parking braking process includes a situation where, after the comfort braking function flag is activated during the historical parking braking process, the real-time braking torque of the vehicle is greater than the initial braking torque, and the difference between the real-time braking torque and the initial braking torque is greater than a first difference threshold; wherein the initial braking torque is the braking torque when the comfort braking function flag is activated during the historical parking braking process; if the number of the first historical parking braking process is greater than a first preset number threshold, a first deceleration correction coefficient is used as the target deceleration correction coefficient; wherein the first deceleration correction coefficient is used to increase the magnitude of the reference target deceleration.

[0013] In one embodiment, obtaining the target deceleration correction coefficient for the current vehicle parking braking process includes: obtaining the number of second historical parking braking processes in which the comfort braking function flag is activated during the historical parking braking process; the second historical parking braking process includes a situation where, after the comfort braking function flag is activated during the historical parking braking process, the real-time braking torque of the vehicle is less than the initial braking torque, and the difference between the real-time braking torque and the initial braking torque is less than a second difference threshold; wherein the initial braking torque is the braking torque when the comfort braking function flag is activated during the historical parking braking process; if the number of the second historical parking braking processes is greater than a second preset number threshold, the second deceleration correction coefficient is used as the target deceleration correction coefficient; wherein the second deceleration correction coefficient is used to reduce the magnitude of the reference target deceleration.

[0014] In one embodiment, obtaining the feedback torque of the vehicle in the current parking braking cycle using the target deceleration and the actual deceleration of the vehicle in the current parking braking cycle includes: obtaining the deceleration difference and the rate of change of the deceleration difference of the vehicle in the current parking braking cycle based on the target deceleration and the actual deceleration; the deceleration difference is the difference between the target deceleration and the actual deceleration; obtaining the feedback torque that matches the deceleration difference and the rate of change of the deceleration difference from a pre-constructed second mapping relationship; the second mapping relationship stores the correspondence between different feedback torques and different deceleration differences and different rates of change of deceleration differences; wherein the feedback torque is negatively correlated with the deceleration difference and the rate of change of the deceleration difference.

[0015] In one embodiment, obtaining the feedforward torque of the vehicle in the current parking braking cycle based on the motor speed and the braking torque of the vehicle in the current parking braking cycle includes: obtaining a reference feedforward torque that matches the motor speed and the braking torque from a pre-constructed third mapping relationship; the third mapping relationship stores the correspondence between different reference feedforward torques and different motor speeds and different braking torques; wherein the reference feedforward torque is positively correlated with the motor speed and the braking torque; and obtaining the feedforward torque of the vehicle in the current parking braking cycle based on the reference feedforward torque.

[0016] In one embodiment, obtaining the feedforward torque of the vehicle in the current parking braking cycle based on the reference feedforward torque includes: obtaining a feedforward torque correction coefficient of the vehicle in the current parking braking cycle according to the slope of the vehicle in the current parking braking cycle, and correcting the reference feedforward torque using the feedforward torque correction coefficient to obtain the corrected feedforward torque; obtaining the feedforward torque of the vehicle in the current parking braking cycle based on the corrected feedforward torque and the braking torque.

[0017] In one embodiment, obtaining the feedforward torque of the vehicle in the current parking braking cycle based on the corrected feedforward torque and the braking torque includes: if the corrected feedforward torque is less than or equal to the braking torque, using the corrected feedforward torque as the feedforward torque of the vehicle in the current parking braking cycle; and if the corrected feedforward torque is greater than the braking torque, using the braking torque as the feedforward torque of the vehicle in the current parking braking cycle.

[0018] In one embodiment, generating a torque control command for the vehicle during the current parking braking cycle based on the target torque includes: obtaining the initial deceleration of the vehicle when the comfort braking function flag is activated during the current parking braking process; obtaining the deceleration transformation gradient of the vehicle during the current parking braking process based on the initial deceleration, and obtaining the torque transformation gradient of the vehicle during the current parking braking process based on the deceleration transformation gradient; generating a torque control command for the vehicle during the current parking braking cycle based on the target torque and the torque transformation gradient; the torque control command is used to adjust the motor torque output of the vehicle to the target torque according to the torque transformation gradient to control the parking braking of the vehicle.

[0019] Secondly, this application also provides an automotive torque control device, comprising:

[0020] The motor speed acquisition module is used to acquire the motor speed of the vehicle in the current parking braking cycle if the comfort braking function flag of the vehicle is in an active state during the vehicle parking braking process.

[0021] The feedforward torque acquisition module is used to acquire the feedforward torque of the vehicle in the current parking braking cycle based on the motor speed and the braking torque of the vehicle in the current parking braking cycle.

[0022] The feedback torque acquisition module is used to acquire the target deceleration of the vehicle in the current parking braking cycle based on the motor speed, and to obtain the feedback torque of the vehicle in the current parking braking cycle using the target deceleration and the actual deceleration of the vehicle in the current parking braking cycle.

[0023] The control command generation module is used to obtain the target torque of the vehicle in the current parking braking cycle based on the feedforward torque, the feedback torque, and the braking torque, and to generate a torque control command for the vehicle in the current parking braking cycle based on the target torque; the torque control command is used to adjust the motor torque output of the vehicle to the target torque to control the parking braking of the vehicle.

[0024] Thirdly, this application also provides a vehicle controller, including a memory and a processor, wherein the memory stores a computer program, and the processor executes the computer program to implement the steps of the method described in any embodiment of the first aspect.

[0025] Fourthly, this application also provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the steps of the method described in any embodiment of the first aspect.

[0026] Fifthly, this application also provides a computer program product, including a computer program that, when executed by a processor, implements the steps of the method described in any embodiment of the first aspect.

[0027] The aforementioned vehicle torque control method, device, vehicle controller, storage medium, and computer program product, during vehicle parking braking, if the comfort braking function flag is active during the current parking braking cycle, acquires the vehicle's motor speed during the current parking braking cycle; based on the motor speed and the vehicle's braking torque during the current parking braking cycle, acquires the vehicle's feedforward torque during the current parking braking cycle; based on the motor speed, acquires the vehicle's target deceleration during the current parking braking cycle, and uses the target deceleration and the vehicle's actual deceleration during the current parking braking cycle to obtain the vehicle's feedback torque during the current parking braking cycle; based on the feedforward torque, feedback torque, and braking torque, acquires the vehicle's target torque during the current parking braking cycle, and generates a torque control command for the vehicle during the current parking braking cycle based on the target torque; the torque control command is used to adjust the vehicle's motor torque output to the target torque to control the vehicle's parking braking. This application allows for the acquisition of the vehicle's motor speed during the parking braking cycle if the comfort braking function is activated. Based on the motor speed and the braking torque of the current parking braking cycle, the feedforward torque for that cycle can be obtained, along with the target deceleration. Combining the target and actual deceleration, the feedback torque for the current parking braking cycle is calculated. Using the feedforward, feedback, and braking torques, the target torque for the current parking braking cycle is then determined. A torque control command is generated based on this target torque to adjust the vehicle's motor torque output to the target torque, thereby controlling the vehicle's parking braking. This method enables parking braking control by controlling the motor torque output based on the feedforward, feedback, and braking torques, thus improving the accuracy of vehicle torque control. Attached Figure Description

[0028] To more clearly illustrate the technical solutions in the embodiments or related technologies of this application, the accompanying drawings used in the description of the embodiments or related technologies will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0029] Figure 1 This is a flowchart illustrating a vehicle torque control method in one embodiment;

[0030] Figure 2 This is a schematic diagram of the process for obtaining the target deceleration in one embodiment;

[0031] Figure 3 This is a schematic diagram of the process for obtaining feedback torque in one embodiment;

[0032] Figure 4This is a schematic diagram of the process for obtaining feedforward torque in one embodiment;

[0033] Figure 5 This is a schematic diagram of the process for generating torque control commands in one embodiment;

[0034] Figure 6 This is a flowchart illustrating a method for controlling the comfort braking torque of a new energy vehicle in one embodiment.

[0035] Figure 7 This is a schematic diagram of the control principle of comfort braking control in one embodiment;

[0036] Figure 8 This is a structural block diagram of an automotive torque control device in one embodiment;

[0037] Figure 9 This is an internal structural diagram of the vehicle controller in one embodiment. Detailed Implementation

[0038] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application.

[0039] In one embodiment, such as Figure 1 As shown, a method for controlling vehicle torque is provided. This embodiment illustrates the application of this method to a vehicle controller. In this embodiment, the method includes the following steps:

[0040] Step S101: During the vehicle parking braking process, if the comfort braking function flag of the vehicle is in an active state during the current parking braking cycle, obtain the motor speed of the vehicle during the current parking braking cycle.

[0041] The comfort braking function flag indicates whether the vehicle's comfort braking function is activated. When the flag is active, the comfort braking function can be activated, which outputs drive torque to suppress the rate of change in vehicle deceleration, thus achieving comfortable braking during parking. The current parking braking cycle refers to any parking braking cycle within the vehicle's parking braking process. This process can consist of multiple parking braking cycles. If the comfort braking function flag is active during the current parking braking cycle, it indicates that the comfort braking function has been activated. The motor speed refers to the real-time motor speed during the current parking braking cycle, which can be obtained through the vehicle's motor speed sensor.

[0042] Specifically, during parking braking, if the vehicle activates the comfort braking function within the current parking braking cycle (i.e., the comfort braking function flag is active), the vehicle controller can collect the motor speed of the vehicle during the current parking braking cycle.

[0043] Step S102: Based on the motor speed and the braking torque of the vehicle in the current parking braking cycle, obtain the feedforward torque of the vehicle in the current parking braking cycle.

[0044] Feedforward torque refers to the feedforward amount in the drive torque control process. This feedforward torque can be calculated from the motor speed and the braking torque of the vehicle in the current parking braking cycle. The braking torque is the torque output to achieve parking braking of the vehicle. This braking torque can be obtained based on the pedal displacement of the vehicle in the current parking braking cycle. Specifically, after obtaining the motor speed, the vehicle controller can also collect the braking torque of the vehicle in the current parking braking cycle, and thus use the motor speed and braking torque to obtain the feedforward torque of the vehicle in the current parking braking cycle.

[0045] Step S103: Based on the motor speed, obtain the target deceleration of the vehicle in the current parking braking cycle, and use the target deceleration and the actual deceleration of the vehicle in the current parking braking cycle to obtain the feedback torque of the vehicle in the current parking braking cycle.

[0046] The target deceleration refers to the deceleration target of the vehicle in the current parking braking cycle, while the actual deceleration refers to the actual deceleration of the vehicle in the current parking braking cycle. The feedback torque is the feedback quantity in the drive torque control process, which can be calculated based on the target deceleration and the actual deceleration.

[0047] Specifically, after obtaining the motor speed, the vehicle controller can first use the motor speed to obtain the target deceleration of the vehicle in the current parking braking cycle, and then use the target deceleration and the actual deceleration of the vehicle in the current parking braking cycle to calculate the feedback torque of the vehicle in the current parking braking cycle.

[0048] Step S104: Based on the feedforward torque, feedback torque, and braking torque, obtain the target torque of the vehicle in the current parking braking cycle, and generate a torque control command for the vehicle in the current parking braking cycle based on the target torque; the torque control command is used to adjust the motor torque output of the vehicle to the target torque to control the parking braking of the vehicle.

[0049] The target torque refers to the final torque control target of the vehicle in the current parking braking cycle. The torque control command is the control command used to control the torque output of the vehicle's motor. This command can be used to adjust the torque output of the vehicle's motor until the target torque is reached, thereby realizing the control of the vehicle's parking braking process.

[0050] Specifically, after obtaining the feedforward torque, feedback torque, and braking torque, the vehicle controller can also obtain the target braking torque for the current parking braking cycle based on these torques. The feedforward torque and feedback torque are mainly used to control the output of the motor drive torque. The feedforward torque can serve as the reference part of the drive torque, while the feedback torque is used to correct the reference part to control the output of the drive torque. The braking torque is the torque generated by the displacement of the brake pedal to control the vehicle to stop. The target torque can be obtained based on the output difference between the drive torque and the braking torque. Based on the target torque, a torque control command for the vehicle in the current parking braking cycle is generated. This torque control command is then used to adjust the output of the vehicle's motor torque until the vehicle's motor torque output reaches the target torque, thereby achieving parking braking control of the vehicle.

[0051] In the aforementioned vehicle torque control method, during vehicle parking braking, if the comfort braking function flag is active during the current parking braking cycle, the motor speed of the vehicle in the current parking braking cycle is obtained; based on the motor speed and the braking torque of the vehicle in the current parking braking cycle, the feedforward torque of the vehicle in the current parking braking cycle is obtained; based on the motor speed, the target deceleration of the vehicle in the current parking braking cycle is obtained, and using the target deceleration and the actual deceleration of the vehicle in the current parking braking cycle, the feedback torque of the vehicle in the current parking braking cycle is obtained; based on the feedforward torque, the feedback torque, and the braking torque, the target torque of the vehicle in the current parking braking cycle is obtained, and a torque control command for the vehicle in the current parking braking cycle is generated based on the target torque; the torque control command is used to adjust the motor torque output of the vehicle to the target torque to control the vehicle's parking braking. This application allows for the acquisition of the vehicle's motor speed during the parking braking cycle if the comfort braking function is activated. Based on the motor speed and the braking torque of the current parking braking cycle, the feedforward torque for that cycle can be obtained, along with the target deceleration. Combining the target and actual deceleration, the feedback torque for the current parking braking cycle is calculated. Using the feedforward, feedback, and braking torques, the target torque for the current parking braking cycle is then determined. A torque control command is generated based on this target torque to adjust the vehicle's motor torque output to the target torque, thereby controlling the vehicle's parking braking. This method enables parking braking control by controlling the motor torque output based on the feedforward, feedback, and braking torques, thus improving the accuracy of vehicle torque control.

[0052] In one embodiment, such as Figure 2 As shown, step S103 may further include:

[0053] Step S201: Obtain the reference target deceleration that matches the motor speed from the pre-constructed first mapping relationship; the first mapping relationship stores the correspondence between different motor speeds and different reference target decelerations; wherein the magnitude of the reference target deceleration is positively correlated with the motor speed.

[0054] The reference target deceleration refers to the target deceleration determined directly based on the motor speed. In this embodiment, in order to improve the accuracy of the target deceleration setting, when calculating the target deceleration, the reference target deceleration can be obtained first based on the motor speed, and then the reference target deceleration can be used to obtain the final target deceleration.

[0055] The first mapping relationship is used to store the correspondence between motor speed and the reference target deceleration. This first mapping relationship can be implemented through a mapping table, and there is a negative correlation between the magnitude of the motor speed and the reference target deceleration. That is, the larger the motor speed, the larger the absolute value of the reference target deceleration. For example, the first mapping relationship can be a mapping table, and some data of this mapping table can be shown in Table 1:

[0056] Table 1 First Mapping Relationship Table

[0057]

[0058] As can be seen, the target deceleration value increases with the increase of motor speed. This method can increase the target deceleration value while increasing motor speed, that is, the magnitude of the benchmark target deceleration is positively correlated with the motor speed.

[0059] Specifically, after obtaining the motor speed, a target deceleration value that is compatible with the motor speed can be obtained from the pre-constructed first mapping relationship, i.e., the first mapping relationship table, and the target deceleration value can be used as the deceleration magnitude of the reference target deceleration.

[0060] Step S202: Based on the benchmark target deceleration, obtain the target deceleration of the vehicle in the current parking braking cycle.

[0061] Then, based on the reference target deceleration, the final target deceleration of the car in the current parking braking cycle can be obtained. This can be done by directly using the reference target deceleration as the target deceleration of the car in the current parking braking cycle, or by further modifying the reference target deceleration to obtain the target deceleration of the car in the current parking braking cycle.

[0062] In this embodiment, a reference target deceleration that matches the motor speed can also be obtained through the first mapping relationship, thereby obtaining the target deceleration of the vehicle in the current parking braking cycle based on the reference target deceleration. This method can improve the accuracy of the target deceleration setting.

[0063] Further, step S202 may further include: obtaining the target deceleration correction coefficient of the vehicle corresponding to the current vehicle parking braking process; the target deceleration correction coefficient is obtained based on the historical parking braking behavior of the vehicle corresponding to the comfort braking function flag being in the active state during historical parking braking processes; and correcting the reference target deceleration using the target deceleration correction coefficient to obtain the target deceleration of the vehicle in the current parking braking cycle.

[0064] The target deceleration correction coefficient is a correction coefficient used to correct the vehicle's target deceleration during the current parking braking process. This deceleration correction coefficient can be obtained based on the vehicle's historical parking behavior after the comfort braking function was activated during previous parking braking processes. The historical parking braking process refers to the parking braking process before the current parking braking process, and the historical parking braking behavior refers to the parking actions during the aforementioned historical parking braking process. Specifically, the vehicle controller can pre-store the target deceleration correction coefficient before the current parking process. This target deceleration correction coefficient can be obtained and stored based on the historical parking braking behavior after the comfort braking function was activated during previous parking braking processes. Therefore, the vehicle controller can obtain the pre-stored target deceleration correction coefficient during the current parking braking process.

[0065] After obtaining the baseline target deceleration and the target deceleration correction coefficient, the vehicle controller can use the target deceleration correction coefficient to correct the baseline target deceleration, thereby obtaining the target deceleration of the vehicle in the current parking braking cycle.

[0066] In this embodiment, after obtaining the benchmark target deceleration, the target deceleration correction coefficient corresponding to the current vehicle parking braking process can also be obtained. This correction coefficient can be obtained based on the historical parking braking behavior after the comfort braking function is activated during historical parking braking processes. Then, the benchmark target deceleration can be realized using the target deceleration correction coefficient. This method can improve the accuracy of the target deceleration setting.

[0067] Furthermore, obtaining the target deceleration correction coefficient for the current vehicle parking braking process may further include: obtaining the number of times the comfort braking function flag is activated during historical parking braking processes; the first historical parking braking process includes a situation where, after the comfort braking function flag is activated during the historical parking braking process, the real-time braking torque of the vehicle is greater than the initial braking torque, and the difference between the real-time braking torque and the initial braking torque is greater than a first difference threshold; wherein the initial braking torque is the braking torque when the comfort braking function flag is activated during the historical parking braking process; if the number of the first historical parking braking processes is greater than a first preset number threshold, the first deceleration correction coefficient is used as the target deceleration correction coefficient; wherein the first deceleration correction coefficient is used to increase the magnitude of the reference target deceleration.

[0068] The first historical parking braking process refers to a parking braking process in which, after the comfort braking function was activated, the braking torque was greater than or equal to the initial braking torque, and the difference between the braking torque and the initial braking torque exceeded a first difference threshold. The initial braking torque refers to the braking torque at the time the comfort braking function was activated during this historical parking braking process. For example, after the comfort braking function was activated, the driver increased the pedal pressure, thus significantly increasing the output braking torque to increase the vehicle's deceleration. In other words, this parking braking process resulted in insufficient deceleration; therefore, the first historical parking braking process refers to a historical parking braking process where insufficient deceleration occurred.

[0069] The first preset number threshold refers to the threshold for the number of times the deceleration is too small. If the number of the first historical parking braking process is greater than the first preset number threshold, it means that there are more historical parking braking processes with insufficient deceleration. In this case, it is necessary to increase the value of the reference target deceleration. Therefore, the target deceleration correction coefficient is set as a correction coefficient to increase the value of the reference target deceleration. For example, it can be set to 1.1, so that the target deceleration is 1.1 times the value of the reference target deceleration.

[0070] Specifically, if, during a parking braking process, the comfort braking function is activated, and the braking torque at a certain moment, i.e., the real-time braking torque, is greater than the braking torque at the activation moment, i.e., the initial braking torque, and the difference between the real-time braking torque and the initial braking torque is greater than a first difference threshold, then this parking braking process is considered the first historical parking braking process. Subsequently, the number of the first historical parking braking processes can be counted. If the number is greater than a set first preset number threshold, it is determined that the driver tends to increase braking demand during the activation of this function, i.e., the baseline target deceleration is too low. Therefore, the corrected target deceleration is equal to the baseline target deceleration before correction multiplied by a first deceleration correction coefficient, which is greater than 1, for example, 1.1.

[0071] In this embodiment, the number of first historical parking braking processes can also be collected. If the number is greater than the first preset number threshold, a first deceleration correction coefficient is set as the target deceleration correction coefficient to increase the magnitude of the reference target deceleration. In this way, when the driver tends to increase the braking demand, the magnitude of the reference target deceleration can be increased, thereby improving the accuracy of the target deceleration setting.

[0072] Similarly, obtaining the target deceleration correction coefficient for the current vehicle parking braking process can further include: obtaining the number of second historical parking braking processes in which the comfort braking function flag is activated during historical parking braking processes; the second historical parking braking process includes a historical parking braking process in which the real-time braking torque of the vehicle is less than the initial braking torque after the comfort braking function flag is activated, and the difference between the real-time braking torque and the initial braking torque is less than a second difference threshold; wherein the initial braking torque is the braking torque when the comfort braking function flag is activated during the historical parking braking process; if the number of second historical parking braking processes is greater than a second preset number threshold, the second deceleration correction coefficient is used as the target deceleration correction coefficient; wherein the second deceleration correction coefficient is used to reduce the magnitude of the reference target deceleration.

[0073] Similarly, the second historical parking braking process refers to a parking braking process in which, after the comfort braking function is activated, the braking torque is less than the initial braking torque, and the difference between the braking torque and the initial braking torque is less than a second difference threshold. This initial braking torque can also refer to the braking torque when the comfort braking function is activated in that historical parking braking process. For example, after the comfort braking function is activated, the driver reduces the pedal pressure, thus significantly reducing the output braking torque to reduce the vehicle's deceleration. In other words, this parking braking process involves excessive deceleration, and the second historical parking braking process refers to a historical parking braking process where excessive deceleration occurred.

[0074] The second preset number threshold refers to the threshold for the number of times the deceleration is too small. If the number of the second historical parking braking process is greater than the second preset number threshold, it means that there are more historical parking braking cases with excessive deceleration. In this case, it is necessary to reduce the value of the reference target deceleration. Therefore, the target deceleration correction coefficient is set as a correction coefficient to reduce the size of the reference target deceleration. For example, it can be set to 0.9, so that the target deceleration is 0.9 times the size of the reference target deceleration.

[0075] Specifically, if, during a parking braking process, the comfort braking function is activated, and the braking torque at a certain moment, i.e., the real-time braking torque, is less than the braking torque at the activation moment, i.e., the initial braking torque, and the difference between the real-time braking torque and the initial braking torque is less than the second difference threshold, then this parking braking process is considered a second historical parking braking process. Subsequently, the number of second historical parking braking processes can be counted. If the number is greater than the set second preset number threshold, it is determined that the driver tends to reduce braking demand during the activation of this function, i.e., the baseline target deceleration is too high. Therefore, the corrected target deceleration is equal to the baseline target deceleration before correction multiplied by the second deceleration correction coefficient, which is less than 1, for example, 0.9.

[0076] In this embodiment, the number of times the second historical parking braking process is collected can also be used. If the number is greater than the second preset number threshold, a second deceleration correction coefficient is set as the target deceleration correction coefficient to reduce the magnitude of the reference target deceleration. In this way, when the driver tends to reduce the braking demand, the magnitude of the reference target deceleration can be reduced, thereby improving the accuracy of the target deceleration setting.

[0077] In one embodiment, such as Figure 3 As shown, step S103 may further include:

[0078] Step S301: Based on the target deceleration and the actual deceleration, obtain the deceleration difference and the rate of change of the deceleration difference of the vehicle in the current parking braking cycle; the deceleration difference is the difference between the target deceleration and the actual deceleration.

[0079] Among them, deceleration difference refers to the difference between the target deceleration and the actual deceleration, such as the difference between the target deceleration and the actual deceleration. The rate of change of deceleration difference refers to the rate of change of deceleration difference, which can be calculated based on the deceleration difference of the current parking braking cycle and the deceleration difference of the previous parking braking cycle.

[0080] Specifically, after obtaining the target deceleration and actual deceleration of the current parking braking cycle, the vehicle controller can also calculate the difference between the target deceleration and the actual deceleration as the deceleration difference of the current parking braking cycle. Furthermore, it can combine the deceleration difference of the current parking braking cycle with the deceleration difference of the previous parking braking cycle to obtain the rate of change of deceleration difference of the current parking braking cycle.

[0081] Step S302: Obtain the feedback torque that matches the deceleration difference and the rate of change of the deceleration difference from the pre-constructed second mapping relationship; the second mapping relationship stores the correspondence between different feedback torques and different deceleration differences and different rates of change of the deceleration difference; wherein the feedback torque is negatively correlated with the deceleration difference and the rate of change of the deceleration difference.

[0082] The second mapping relationship refers to the mapping relationship between feedback torque and deceleration difference and the rate of change of deceleration difference. This mapping relationship can be a mapping relationship table that stores the correspondence between different feedback torques and different deceleration differences and different rates of change of deceleration difference. Furthermore, there is a negative correlation between feedback torque and deceleration difference and the rate of change of deceleration difference. That is, the larger the deceleration difference, the smaller the feedback torque, and similarly, the smaller the deceleration difference, the larger the feedback torque.

[0083] For example, the second mapping relationship can be a mapping relationship table, and some data of the mapping relationship table can be shown in Table 2:

[0084] Table 2 Second Mapping Relationship Table

[0085]

[0086] The horizontal axis represents the deceleration difference, the vertical axis represents the rate of change of the deceleration difference, and the value represents the feedback torque. It can be seen that when the rate of change of the deceleration difference remains constant, as the deceleration difference increases, i.e., from -2 to 2, the feedback torque value also decreases accordingly. Similarly, when the deceleration difference remains constant, as the rate of change of the deceleration difference increases, i.e. from -20 to 20, the feedback torque value also decreases accordingly.

[0087] Subsequently, the vehicle controller can obtain a feedback torque from the second mapping relationship that matches the deceleration difference and the rate of change of the deceleration difference in the current parking braking cycle, and use it as the feedback torque for the current parking braking cycle.

[0088] In this embodiment, the deceleration difference and the rate of change of the deceleration difference in the current parking braking cycle can also be obtained based on the difference between the target deceleration and the actual deceleration. Then, the second mapping relationship can be queried using the above-mentioned deceleration difference and the rate of change of the deceleration difference to obtain the feedback torque of the current parking braking cycle. This method can improve the accuracy of the feedback torque calculation.

[0089] In one embodiment, such as Figure 4 As shown, step S102 may further include:

[0090] Step S401: Obtain the reference feedforward torque that matches the motor speed and braking torque from the pre-constructed third mapping relationship; the third mapping relationship stores the correspondence between different reference feedforward torques and different motor speeds and different braking torques; wherein the reference feedforward torque is positively correlated with the motor speed and braking torque.

[0091] The reference feedforward torque refers to the feedforward torque directly determined based on the motor speed and the output braking torque. In this embodiment, to improve the accuracy of the feedforward torque setting, the reference feedforward torque can be obtained first based on the motor speed and the magnitude of the braking torque, and then the final feedforward torque can be obtained using the reference feedforward torque.

[0092] The third mapping relationship is the mapping relationship between the reference feedforward torque and the motor speed and braking torque. This mapping relationship can be a mapping relationship table that stores the correspondence between different reference feedforward torques and different motor speeds and braking torques. Furthermore, the reference feedforward torque is positively correlated with both the motor speed and the braking torque. That is, the higher the motor speed, the higher the reference feedforward torque. Similarly, the higher the braking torque, the higher the reference feedforward torque.

[0093] For example, the third mapping relationship can be a mapping relationship table, and some data of this mapping relationship table can be shown in Table 3:

[0094] Table 3 Third Mapping Relationship Table

[0095]

[0096] The graph shows the braking torque on the horizontal axis and the motor speed on the vertical axis, with the value representing the feedforward torque. It can be seen that, with the motor speed constant, as the braking torque increases from 0 to 400, the feedforward torque value also increases accordingly. Similarly, with the braking torque constant, as the motor speed increases from 0 to 400, the feedforward torque value also increases accordingly.

[0097] Specifically, after obtaining the motor speed and braking torque, the vehicle controller can also use the motor speed and braking torque to query the third mapping relationship, thereby obtaining the reference feedforward torque that matches the motor speed and braking torque.

[0098] Step S402: Based on the reference feedforward torque, obtain the feedforward torque of the vehicle in the current parking braking cycle.

[0099] Then, the final feedforward torque of the vehicle in the current parking braking cycle can be obtained based on the reference feedforward torque. This can be done by directly using the reference feedforward torque as the feedforward torque of the vehicle in the current parking braking cycle, or by further modifying the reference feedforward torque to obtain the feedforward torque of the vehicle in the current parking braking cycle.

[0100] In this embodiment, a reference feedforward torque that matches the motor speed and braking torque can also be obtained through a third mapping relationship. Based on the reference feedforward torque, the feedforward torque of the vehicle in the current parking braking cycle can be obtained. This method can improve the accuracy of the feedforward torque setting.

[0101] Furthermore, step S402 may further include: obtaining the feedforward torque correction coefficient of the vehicle in the current parking braking cycle based on the slope of the vehicle in the current parking braking cycle, and correcting the reference feedforward torque using the feedforward torque correction coefficient to obtain the corrected feedforward torque; obtaining the feedforward torque of the vehicle in the current parking braking cycle based on the corrected feedforward torque and the braking torque.

[0102] In this embodiment, similar to the target deceleration, in order to improve the accuracy of the feedforward torque setting, the vehicle controller can also improve the accuracy of the feedforward torque by correcting the reference feedforward torque. For example, when the car is on a slope, it is usually necessary to superimpose the slope component on the reference feedforward torque to improve the accuracy of parking braking.

[0103] The corrected feedforward torque refers to the feedforward torque obtained by correcting the reference feedforward torque using a feedforward torque correction coefficient. This feedforward torque correction coefficient can be determined based on the slope of the vehicle during the current parking braking cycle. For example, the slope component can be calculated by using the slope of the vehicle during the current parking braking cycle, and then the feedforward torque correction coefficient can be obtained using the slope component. The reference feedforward torque can then be corrected using the feedforward torque correction coefficient to obtain the corrected feedforward torque.

[0104] After obtaining the corrected feedforward torque, the corrected feedforward torque can be combined with the braking torque to obtain the feedforward torque of the vehicle in the current parking braking cycle.

[0105] In this embodiment, a reference feedforward torque matching the motor speed and braking torque can also be obtained through a third mapping relationship. At the same time, the reference feedforward torque can be corrected by combining the slope of the vehicle during the current parking braking cycle. In this way, the reference feedforward torque can be obtained by combining the braking torque and the feedforward torque can be corrected by combining the vehicle slope, thereby improving the accuracy of the feedforward torque acquisition.

[0106] Furthermore, obtaining the feedforward torque of the vehicle in the current parking braking cycle based on the corrected feedforward torque and the braking torque can further include: if the corrected feedforward torque is less than or equal to the braking torque, using the corrected feedforward torque as the feedforward torque of the vehicle in the current parking braking cycle; if the corrected feedforward torque is greater than the braking torque, using the braking torque as the feedforward torque of the vehicle in the current parking braking cycle.

[0107] In this embodiment, after obtaining the corrected feedforward torque, the corrected feedforward torque can be compared with the braking torque of the current parking braking cycle to ultimately determine whether to use the corrected feedforward torque as the feedforward torque of the vehicle in the current parking braking cycle. If the corrected feedforward torque is less than or equal to the braking torque, the corrected feedforward torque is directly used as the feedforward torque of the vehicle in the current parking braking cycle. However, if the corrected feedforward torque is greater than the braking torque, in order to avoid the corrected feedforward torque being too large and causing insufficient vehicle deceleration, the corrected feedforward torque needs to be limited to not being greater than the braking torque. That is, if the corrected feedforward torque is greater than the braking torque, the braking torque is directly used as the feedforward torque of the vehicle in the current parking braking cycle.

[0108] In this embodiment, to avoid insufficient vehicle deceleration due to excessively large corrected feedforward torque, the corrected feedforward torque can be limited, that is, the corrected feedforward torque must be less than or equal to the braking torque. This method can further improve the safety and stability of parking braking.

[0109] In one embodiment, such as Figure 5 As shown, step S104 may further include:

[0110] Step S501: Obtain the initial deceleration of the vehicle when the comfort braking function flag is activated during the current parking braking process.

[0111] The initial deceleration of a vehicle refers to the vehicle's deceleration when the comfort braking function flag is activated during the current parking braking process. Specifically, the vehicle controller can obtain the vehicle's deceleration at the current moment when the comfort braking function is activated, and record it as the initial deceleration of the vehicle during the current parking braking process.

[0112] Step S502: Based on the initial deceleration of the vehicle, obtain the deceleration transformation gradient of the vehicle during the current parking braking process, and based on the deceleration transformation gradient, obtain the torque transformation gradient of the vehicle during the current parking braking process.

[0113] The deceleration transformation gradient refers to the adjustment gradient of the vehicle's deceleration, that is, the adjustment gradient for adjusting the deceleration to the target deceleration. In this embodiment, the deceleration transformation gradient can be calculated based on the vehicle's initial deceleration and a pre-set expected stopping time. For example, the deceleration transformation gradient... It can be calculated using the following formula:

[0114]

[0115] in, Indicates the initial deceleration of the car. A value of zero indicates that the target deceleration is zero at zero rotational speed. This indicates the expected parking time.

[0116] After obtaining the deceleration transformation gradient, the torque transformation gradient of the car during the current parking and braking process can be further calculated. For example, the transformation gradient of the car's resultant force can be calculated first based on the deceleration transformation gradient, and then the torque transformation gradient can be calculated using the transformation gradient of the car's resultant force.

[0117] Step S503: Generate torque control command for the vehicle during the current parking braking cycle based on the target torque and torque transformation gradient; the torque control command is used to adjust the motor torque output of the vehicle to the target torque according to the torque transformation gradient, so as to control the parking braking of the vehicle.

[0118] Finally, the target torque and torque transformation gradient can be used to generate a torque control command for the vehicle during the current parking braking cycle. This torque control command can control the vehicle's motor torque output to adjust to the target torque according to the torque transformation gradient in order to control the vehicle's parking braking, thereby further improving the accuracy of motor torque output control.

[0119] In this embodiment, the initial deceleration of the vehicle when the comfort braking function flag is activated can be collected to obtain the deceleration transformation gradient, thereby obtaining the torque transformation gradient. The torque control command can then be generated by combining the torque transformation gradient. This method can further improve the accuracy of motor torque output control.

[0120] In one embodiment, before step S101, the method may further include: if the vehicle meets preset conditions during the current parking braking cycle, then determining that the comfort braking function flag of the vehicle is activated during the current parking braking cycle; wherein the preset conditions include at least one of the following: the actual deceleration of the vehicle meets a preset deceleration range, the motor speed of the vehicle meets a preset motor speed range, the brake pedal displacement of the vehicle meets a preset displacement range, the vehicle is in a forward gear, the vehicle slip ratio or wheel deceleration is less than a preset threshold, the motor speed change rate of the vehicle is within a preset change rate range, and the comfort braking function activation duration is less than a preset activation duration threshold.

[0121] In this embodiment, upon entering the current parking braking cycle, it is also necessary to determine whether the comfort braking function can be activated within the current parking braking cycle. Activation of the comfort braking function within the current parking braking cycle is determined only when the following preset conditions are met, i.e., the comfort braking function flag is activated within the current parking braking cycle. These preset conditions include: the vehicle's actual deceleration meets a preset deceleration range (i.e., the deceleration is within the range); the vehicle's motor speed meets a preset motor speed range (i.e., the motor speed is within the range); the vehicle's brake pedal displacement meets a preset displacement range (i.e., the brake pedal displacement is within the range); the vehicle is in drive (D gear); the vehicle's slip ratio or wheel deceleration is less than a preset threshold (i.e., the wheel end state is not slipping); the vehicle's motor speed change rate is within a preset change rate range (i.e., the motor speed change rate is within the range); and the comfort braking function activation duration is less than a preset activation duration threshold (i.e., the function activation operation time is less than the threshold).

[0122] In this embodiment, it is also possible to determine whether the comfort braking function flag is activated in the current parking braking cycle by judging whether the vehicle meets the preset conditions in the current parking braking cycle. This method can also improve the intelligence of comfort braking function activation.

[0123] In one embodiment, a method for controlling the comfort braking torque of a new energy vehicle is also provided, such as... Figure 6 As shown, the method includes the following steps:

[0124] Step 1: The vehicle control unit (VCU) monitors the vehicle motor speed n, vehicle speed V, braking torque, gear position, and other information in real time.

[0125] Step 2: Calculate the actual deceleration of the vehicle based on the vehicle speed, and calculate the rate of change of the motor speed based on the motor speed.

[0126] The basic principle is as follows:

[0127] Calculate the actual longitudinal deceleration and rate of change of rotational speed based on the derivatives of vehicle speed and motor speed:

[0128]

[0129]

[0130] In the formula, For actual deceleration, This represents the rate of change of motor speed.

[0131] Step 3: Activate the flag based on the calculation function of deceleration, motor speed, braking torque, gear position, and wheel end status.

[0132] The feature will be activated if all of the following conditions are met:

[0133] 1. The deceleration is within the range;

[0134] 2. The motor speed is within the specified range;

[0135] 3. The braking torque is within the specified range;

[0136] 4. The gear is set to D;

[0137] 5. The wheel end is in a non-slipping state;

[0138] 6. The rate of change of motor speed is within the specified range;

[0139] 7. The function activation time is less than the threshold.

[0140] Step 4: Calculate the feedforward torque based on the function activation flag, braking torque, motor speed, and slope.

[0141] When the function flag is activated, the feedforward torque is calculated by referring to Table 3 with braking torque as the horizontal axis and motor speed as the vertical axis. The greater the braking torque and the greater the motor speed, the greater the feedforward torque.

[0142] Furthermore, to improve adaptability under different slopes, the slope component force is calculated based on the slope, and the slope component force needs to be superimposed after obtaining the feedforward torque.

[0143] To avoid excessive feedforward torque of the superimposed slope component leading to insufficient vehicle deceleration, the feedforward torque of the superimposed slope component needs to be limited, i.e., the feedforward torque of the superimposed slope component must be less than the braking torque.

[0144] Step 5: Calculate the feedback torque based on the motor speed and actual deceleration.

[0145] The target deceleration is calculated by referring to Table 1 with the motor speed as the horizontal axis. The difference between the target deceleration and the actual deceleration and its rate of change are used as control factors for closed-loop control. That is, the feedback torque is obtained by referring to Table 2.

[0146] Step 6: Set the deceleration gradient based on the deceleration at the moment of function activation to avoid either setting the deceleration too small, resulting in a loss of deceleration feel, or setting the deceleration too large, resulting in an insignificant anti-pitch effect. The target deceleration is limited by the deceleration gradient.

[0147] Starting with the initial deceleration of the car at the moment of function activation, assuming the target deceleration is zero at zero RPM, and setting the desired stopping time, the gradient is equal to:

[0148]

[0149] in, Indicates the initial deceleration of the car. Zero, This indicates the expected parking time.

[0150] Step 7: Correct the target deceleration based on the function activation flag and braking torque.

[0151] If the braking torque changes during the activation of the function flag and conforms to the following rule:

[0152] If the real-time braking torque is greater than the initial braking torque at the activation time, and the difference is greater than the first difference threshold, then it is calculated once. If the number of times is greater than the first preset number of times threshold, it is determined that the driver tends to increase the braking demand during the activation of the function. If the function target deceleration is too low, the target deceleration needs to be increased. The corrected target deceleration is equal to the target deceleration before correction multiplied by the first deceleration correction coefficient. The first deceleration correction coefficient is greater than 1, for example, 1.1.

[0153] If the real-time braking torque is less than the initial braking torque at the activation time, and the difference is less than the second difference threshold, then it is calculated once. If the number of times is greater than the second preset number of times threshold, it is determined that the driver tends to reduce the braking demand during the activation of the function. In this case, the function target deceleration is too high and the target deceleration needs to be reduced. The corrected target deceleration is equal to the target deceleration before correction multiplied by the second deceleration correction coefficient. The second deceleration correction coefficient is less than 1, for example, 0.9.

[0154] Ultimately, by setting an appropriate target deceleration, driving problems caused by unreasonable deceleration settings can be avoided.

[0155] The control principle of comfort braking control is as follows: Figure 7As shown, when the function activation flag is met, function ① is activated. The expected deceleration is set using empirical values, and the feedforward torque is calculated by looking up a table. However, the actual deceleration may deviate from the expected value during control. Therefore, the expected deceleration and actual deceleration are observed simultaneously for feedback correction. The green motor speed in the diagram represents the expected deceleration execution example. If it's gray, it indicates the stopping time is too short, and the initial base torque value is too small and needs to be increased. If it's orange, it indicates the stopping time is too long, and the initial base torque value is too large and needs to be decreased. This objective is achieved by fixing the stopping time to limit deceleration changes at all times, thereby controlling the torque and ensuring deceleration according to the green curve. ② indicates that when the vehicle comes to a stop, the control torque needs to decrease to zero according to the slope. That is, after the vehicle speed drops to zero, the torque is controlled to decrease to zero using a pre-set torque exit gradient, i.e., the slope, thus canceling the torque output. ③ indicates that the torque has decreased to zero. Simultaneously, the driver's brake pedal behavior is monitored during ① to ②. Generally, the brake pedal displacement is a constant value during normal braking. If the brake pedal displacement changes, it indicates that the current deceleration does not meet the driver's needs, thus correcting the torque accordingly.

[0156] This embodiment can improve the driver's parking comfort without requiring emergency braking by controlling motor speed, braking torque, and deceleration. Furthermore, by setting reasonable function entry conditions, it avoids insufficient deceleration caused by abnormal torque, or even acceleration. The open-loop and closed-loop control methods improve the adaptability of the function and avoid the loss of deceleration feel or insignificant anti-pitch benefits caused by unreasonable deceleration settings.

[0157] It should be understood that although the steps in the flowcharts of the embodiments described above are shown sequentially according to the arrows, these steps are not necessarily executed in the order indicated by the arrows. Unless explicitly stated herein, there is no strict order restriction on the execution of these steps, and they can be executed in other orders. Moreover, at least some steps in the flowcharts of the embodiments described above may include multiple steps or multiple stages. These steps or stages are not necessarily completed at the same time, but can be executed at different times. The execution order of these steps or stages is not necessarily sequential, but can be performed alternately or in turn with other steps or at least some of the steps or stages of other steps.

[0158] Based on the same inventive concept, this application also provides an automotive torque control device for implementing the aforementioned automotive torque control method. The solution provided by this device is similar to the implementation described in the above method; therefore, the specific limitations in one or more automotive torque control device embodiments provided below can be found in the limitations of the automotive torque control method described above, and will not be repeated here.

[0159] In one embodiment, such as Figure 8 As shown, an automotive torque control device is provided, including: a motor speed acquisition module 801, a feedforward torque acquisition module 802, a feedback torque acquisition module 803, and a control command generation module 804, wherein:

[0160] The motor speed acquisition module 801 is used to acquire the motor speed of the vehicle during the current parking braking cycle if the comfort braking function flag of the vehicle is in an active state during the current parking braking cycle.

[0161] The feedforward torque acquisition module 802 is used to acquire the feedforward torque of the vehicle in the current parking braking cycle based on the motor speed and the braking torque of the vehicle in the current parking braking cycle.

[0162] The feedback torque acquisition module 803 is used to obtain the target deceleration of the vehicle in the current parking braking cycle based on the motor speed, and to obtain the feedback torque of the vehicle in the current parking braking cycle using the target deceleration and the actual deceleration of the vehicle in the current parking braking cycle.

[0163] The control command generation module 804 is used to obtain the target torque of the vehicle in the current parking braking cycle based on the feedforward torque, feedback torque and braking torque, and generate torque control commands for the vehicle in the current parking braking cycle based on the target torque; the torque control commands are used to adjust the motor torque output of the vehicle to the target torque in order to control the parking braking of the vehicle.

[0164] In one embodiment, the feedback torque acquisition module 803 is further configured to acquire a reference target deceleration that matches the motor speed from a pre-built first mapping relationship; the first mapping relationship stores the correspondence between different motor speeds and different reference target decelerations; wherein the magnitude of the reference target deceleration is positively correlated with the motor speed; and based on the reference target deceleration, the target deceleration of the vehicle in the current parking braking cycle is acquired.

[0165] In one embodiment, the feedback torque acquisition module 803 is further used to acquire the target deceleration correction coefficient of the vehicle corresponding to the current vehicle parking braking process; the target deceleration correction coefficient is obtained based on the historical parking braking behavior of the vehicle corresponding to the comfort braking function flag being in the active state during historical parking braking processes; the target deceleration is corrected using the target deceleration correction coefficient to obtain the target deceleration of the vehicle in the current parking braking cycle.

[0166] In one embodiment, the feedback torque acquisition module 803 is further configured to acquire the number of times the comfort braking function flag is activated during a historical parking braking process; the first historical parking braking process includes a situation where, after the comfort braking function flag is activated during the historical parking braking process, the real-time braking torque of the vehicle is greater than the initial braking torque, and the difference between the real-time braking torque and the initial braking torque is greater than a first difference threshold; wherein the initial braking torque is the braking torque when the comfort braking function flag is activated during the historical parking braking process; if the number of the first historical parking braking process is greater than a first preset number threshold, a first deceleration correction coefficient is used as a target deceleration correction coefficient; wherein the first deceleration correction coefficient is used to increase the magnitude of the reference target deceleration.

[0167] In one embodiment, the feedback torque acquisition module 803 is further configured to acquire the number of times the comfort braking function flag is activated during a historical parking braking process; the second historical parking braking process includes a situation where, after the comfort braking function flag is activated during a historical parking braking process, the real-time braking torque of the vehicle is less than the initial braking torque, and the difference between the real-time braking torque and the initial braking torque is less than a second difference threshold; wherein the initial braking torque is the braking torque when the comfort braking function flag is activated during the historical parking braking process; if the number of the second historical parking braking process is greater than a second preset number threshold, a second deceleration correction coefficient is used as the target deceleration correction coefficient; wherein the second deceleration correction coefficient is used to reduce the magnitude of the reference target deceleration.

[0168] In one embodiment, the feedback torque acquisition module 803 is further configured to acquire the deceleration difference and the rate of change of deceleration difference of the vehicle in the current parking braking cycle based on the target deceleration and the actual deceleration; the deceleration difference is the difference between the target deceleration and the actual deceleration; and to acquire the feedback torque that matches the deceleration difference and the rate of change of deceleration difference from a pre-constructed second mapping relationship; the second mapping relationship stores the correspondence between different feedback torques and different deceleration differences and different rates of change of deceleration difference; wherein the feedback torque is negatively correlated with the deceleration difference and the rate of change of deceleration difference.

[0169] In one embodiment, the feedforward torque acquisition module 802 is further configured to acquire a reference feedforward torque that matches the motor speed and braking torque from a pre-built third mapping relationship; the third mapping relationship stores the correspondence between different reference feedforward torques and different motor speeds and different braking torques; wherein the reference feedforward torque is positively correlated with the motor speed and braking torque; based on the reference feedforward torque, the feedforward torque of the vehicle in the current parking braking cycle is acquired.

[0170] In one embodiment, the feedforward torque acquisition module 802 is further configured to acquire the feedforward torque correction coefficient of the vehicle in the current parking braking cycle based on the slope of the vehicle in the current parking braking cycle, and use the feedforward torque correction coefficient to correct the reference feedforward torque to obtain the corrected feedforward torque; and obtain the feedforward torque of the vehicle in the current parking braking cycle based on the corrected feedforward torque and the braking torque.

[0171] In one embodiment, the feedforward torque acquisition module 802 is further configured to use the corrected feedforward torque as the feedforward torque of the vehicle in the current parking braking cycle when the corrected feedforward torque is less than or equal to the braking torque; and to use the braking torque as the feedforward torque of the vehicle in the current parking braking cycle when the corrected feedforward torque is greater than the braking torque.

[0172] In one embodiment, the control command generation module 804 is further configured to obtain the initial deceleration of the vehicle when the comfort braking function flag is activated during the current parking braking process; obtain the deceleration transformation gradient of the vehicle during the current parking braking process based on the initial deceleration, and obtain the torque transformation gradient of the vehicle during the current parking braking process based on the deceleration transformation gradient; generate a torque control command for the vehicle in the current parking braking cycle based on the target torque and the torque transformation gradient; the torque control command is used to adjust the motor torque output of the vehicle to the target torque according to the torque transformation gradient to control the parking braking of the vehicle.

[0173] The modules in the aforementioned automotive torque control device can be implemented entirely or partially through software, hardware, or a combination thereof. These modules can be embedded in the processor of the vehicle controller in hardware form or independent of it, or stored in the memory of the vehicle controller in software form, so that the processor can call and execute the corresponding operations of each module.

[0174] In one embodiment, a vehicle controller is provided, the internal structure of which is shown in the figure below. Figure 9As shown, the vehicle controller includes a processor, memory, input / output interfaces, and a communication interface. The processor, memory, and input / output interfaces are connected via a system bus, and the communication interface is also connected to the system bus via the input / output interfaces. The processor provides computational and control capabilities. The memory includes non-volatile storage media and internal memory. The non-volatile storage media stores computer programs. The internal memory provides an environment for the execution of the computer programs stored in the non-volatile storage media. The input / output interfaces are used for exchanging information between the processor and external devices. The communication interface is used for wired or wireless communication with external terminals; wireless communication can be achieved through Wi-Fi, mobile cellular networks, NFC (Near Field Communication), or other technologies. When the computer program is executed by the processor, it implements a vehicle torque control method.

[0175] Those skilled in the art will understand that Figure 9 The structure shown is merely a block diagram of a portion of the structure related to the present application and does not constitute a limitation on the vehicle controller to which the present application is applied. A specific vehicle controller may include more or fewer components than those shown in the figure, or combine certain components, or have different component arrangements.

[0176] In one embodiment, a vehicle controller is also provided, including a memory and a processor, wherein the memory stores a computer program, and the processor executes the computer program to implement the steps in the above method embodiments.

[0177] In one embodiment, a computer-readable storage medium is provided having a computer program stored thereon that, when executed by a processor, implements the steps in the above method embodiments.

[0178] In one embodiment, a computer program product is provided, including a computer program that, when executed by a processor, implements the steps in the above method embodiments.

[0179] 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, and the collection, use and processing of the relevant data must comply with relevant regulations.

[0180] Those skilled in the art will understand that all or part of the processes in the above embodiments can be implemented by a computer program instructing related hardware. The computer program can be stored in a non-volatile computer-readable storage medium. When executed, the computer program can include the processes of the embodiments described above. Any references to memory, databases, or other media used in the embodiments provided in this application can include at least one of non-volatile and volatile memory. Non-volatile memory can include read-only memory (ROM), magnetic tape, floppy disk, flash memory, optical memory, high-density embedded non-volatile memory, resistive random access memory (ReRAM), magnetic random access memory (MRAM), ferroelectric random access memory (FRAM), phase change memory (PCM), graphene memory, etc. Volatile memory can include random access memory (RAM) or external cache memory, etc. By way of illustration and not limitation, RAM can take many forms, such as Static Random Access Memory (SRAM) or Dynamic Random Access Memory (DRAM). The databases involved in the embodiments provided in this application may include at least one type of relational database and non-relational database. Non-relational databases may include, but are not limited to, blockchain-based distributed databases. The processors involved in the embodiments provided in this application may be general-purpose processors, central processing units, graphics processing units, digital signal processors, programmable logic devices, quantum computing-based data processing logic devices, etc., and are not limited to these.

[0181] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0182] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of this application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this application should be determined by the appended claims.

Claims

1. A method for controlling automobile torque, characterized in that, The method includes: During vehicle parking braking, if the comfort braking function flag is active during the current parking braking cycle, the motor speed of the vehicle during the current parking braking cycle is obtained; the comfort braking function flag is used to activate the comfort braking function, which is used to suppress the rate of change of vehicle deceleration by outputting drive torque, so as to achieve comfortable braking during parking. Based on the motor speed and the vehicle's braking torque in the current parking braking cycle, the feedforward torque of the vehicle in the current parking braking cycle is obtained; Based on the motor speed, the target deceleration of the vehicle in the current parking braking cycle is obtained, and the feedback torque of the vehicle in the current parking braking cycle is obtained using the target deceleration and the actual deceleration of the vehicle in the current parking braking cycle. The target torque of the vehicle in the current parking braking cycle is obtained based on the feedforward torque, the feedback torque, and the braking torque. The feedforward torque and the feedback torque are used to control the output of the motor drive torque. The feedforward torque serves as a reference portion of the motor drive torque, and the feedback torque is used to correct the reference portion to control the output of the motor drive torque. The braking torque is a torque generated based on the brake pedal displacement for controlling the vehicle to stop. The target torque is obtained based on the output difference between the motor drive torque and the braking torque, and the target torque is used to generate torque control commands for the vehicle in the current parking braking cycle. The system obtains the initial deceleration of the vehicle when the comfort braking function flag is activated during the current parking braking process; based on the initial deceleration, it obtains the deceleration transformation gradient of the vehicle during the current parking braking process, and based on the deceleration transformation gradient, it obtains the torque transformation gradient of the vehicle during the current parking braking process; it generates a torque control command for the vehicle in the current parking braking cycle based on the target torque and the torque transformation gradient; the torque control command is used to adjust the motor torque output of the vehicle to the target torque according to the torque transformation gradient, so as to control the parking braking of the vehicle.

2. The method according to claim 1, characterized in that, The step of obtaining the target deceleration of the vehicle in the current parking braking cycle based on the motor speed includes: From a pre-constructed first mapping relationship, a benchmark target deceleration that matches the motor speed is obtained; the first mapping relationship stores the correspondence between different motor speeds and different benchmark target decelerations; wherein the magnitude of the benchmark target deceleration is positively correlated with the motor speed; Based on the benchmark target deceleration, the target deceleration of the vehicle in the current parking braking cycle is obtained.

3. The method according to claim 2, characterized in that, The step of obtaining the target deceleration of the vehicle in the current parking braking cycle based on the benchmark target deceleration includes: The target deceleration correction coefficient for the vehicle corresponding to the current parking braking process is obtained; the target deceleration correction coefficient is obtained based on the historical parking braking behavior of the vehicle corresponding to the historical parking braking process in which the comfort braking function flag is in an active state. The target deceleration is corrected using the target deceleration correction coefficient to obtain the target deceleration of the vehicle in the current parking braking cycle.

4. The method according to claim 3, characterized in that, The step of obtaining the target deceleration correction coefficient for the vehicle corresponding to the current vehicle parking braking process includes: The number of times the comfort braking function flag is activated during the historical parking braking process is obtained; the first historical parking braking process includes a situation where, after the comfort braking function flag is activated during the historical parking braking process, the real-time braking torque of the vehicle is greater than the initial braking torque, and the difference between the real-time braking torque and the initial braking torque is greater than a first difference threshold; wherein the initial braking torque is the braking torque when the comfort braking function flag is activated during the historical parking braking process. If the number of the first historical parking braking process is greater than the first preset number threshold, the first deceleration correction coefficient is used as the target deceleration correction coefficient; wherein, the first deceleration correction coefficient is used to increase the magnitude of the reference target deceleration.

5. The method according to claim 3, characterized in that, The step of obtaining the target deceleration correction coefficient for the vehicle corresponding to the current vehicle parking braking process includes: The number of times the comfort braking function flag is activated during the historical parking braking process is obtained; the second historical parking braking process includes the situation where, after the comfort braking function flag is activated during the historical parking braking process, the real-time braking torque of the vehicle is less than the initial braking torque, and the difference between the real-time braking torque and the initial braking torque is less than a second difference threshold; wherein the initial braking torque is the braking torque when the comfort braking function flag is activated during the historical parking braking process. If the number of the second historical parking braking process is greater than the second preset number threshold, the second deceleration correction coefficient is used as the target deceleration correction coefficient; wherein, the second deceleration correction coefficient is used to reduce the magnitude of the reference target deceleration.

6. The method according to claim 1, characterized in that, The step of obtaining the feedback torque of the vehicle in the current parking braking cycle by utilizing the target deceleration and the actual deceleration of the vehicle in the current parking braking cycle includes: Based on the target deceleration and the actual deceleration, the deceleration difference and the rate of change of the deceleration difference of the vehicle in the current parking braking cycle are obtained; the deceleration difference is the difference between the target deceleration and the actual deceleration. From the pre-constructed second mapping relationship, a feedback torque matching the deceleration difference and the rate of change of the deceleration difference is obtained; the second mapping relationship stores the correspondence between different feedback torques and different deceleration differences and different rates of change of the deceleration difference; wherein the feedback torque is negatively correlated with the deceleration difference and the rate of change of the deceleration difference.

7. The method according to claim 1, characterized in that, The step of obtaining the feedforward torque of the vehicle in the current parking braking cycle based on the motor speed and the braking torque of the vehicle in the current parking braking cycle includes: From the pre-constructed third mapping relationship, a reference feedforward torque that matches the motor speed and the braking torque is obtained; the third mapping relationship stores the correspondence between different reference feedforward torques and different motor speeds and different braking torques; wherein the reference feedforward torque is positively correlated with the motor speed and the braking torque; Based on the reference feedforward torque, the feedforward torque of the vehicle in the current parking braking cycle is obtained.

8. The method according to claim 7, characterized in that, The step of obtaining the feedforward torque of the vehicle in the current parking braking cycle based on the reference feedforward torque includes: Based on the slope of the vehicle in the current parking braking cycle, the feedforward torque correction coefficient of the vehicle in the current parking braking cycle is obtained, and the reference feedforward torque is corrected using the feedforward torque correction coefficient to obtain the corrected feedforward torque. The feedforward torque of the vehicle in the current parking braking cycle is obtained based on the corrected feedforward torque and the braking torque.

9. The method according to claim 8, characterized in that, The step of obtaining the feedforward torque of the vehicle in the current parking braking cycle based on the corrected feedforward torque and the braking torque includes: If the corrected feedforward torque is less than or equal to the braking torque, the corrected feedforward torque shall be used as the feedforward torque of the vehicle in the current parking braking cycle; If the corrected feedforward torque is greater than the braking torque, the braking torque is used as the feedforward torque of the vehicle in the current parking braking cycle.

10. A torque control device for automobiles, characterized in that, The device includes: The motor speed acquisition module is used to acquire the motor speed of the vehicle during the current parking braking cycle if the comfort braking function flag is active during the current parking braking cycle. The comfort braking function flag is used to activate the comfort braking function, which is used to suppress the rate of change of vehicle deceleration by outputting drive torque to achieve comfortable braking during parking. The feedforward torque acquisition module is used to acquire the feedforward torque of the vehicle in the current parking braking cycle based on the motor speed and the braking torque of the vehicle in the current parking braking cycle. The feedback torque acquisition module is used to acquire the target deceleration of the vehicle in the current parking braking cycle based on the motor speed, and to obtain the feedback torque of the vehicle in the current parking braking cycle using the target deceleration and the actual deceleration of the vehicle in the current parking braking cycle. A control command generation module is used to obtain the target torque of the vehicle in the current parking braking cycle based on the feedforward torque, the feedback torque, and the braking torque; wherein, the feedforward torque and the feedback torque are used to control the output of the motor drive torque, the feedforward torque serves as a reference portion of the motor drive torque, and the feedback torque is used to correct the reference portion to control the output of the motor drive torque; the braking torque is a torque generated based on the brake pedal displacement for controlling the vehicle to stop, and the target torque is obtained based on the output difference between the motor drive torque and the braking torque, and the target torque is used to generate torque control commands for the vehicle in the current parking braking cycle; The control command generation module is further configured to obtain the initial deceleration of the vehicle when the comfort braking function flag is activated during the current parking braking process; obtain the deceleration transformation gradient of the vehicle during the current parking braking process based on the initial deceleration, and obtain the torque transformation gradient of the vehicle during the current parking braking process based on the deceleration transformation gradient; generate a torque control command for the vehicle in the current parking braking cycle based on the target torque and the torque transformation gradient; the torque control command is used to adjust the motor torque output of the vehicle to the target torque according to the torque transformation gradient, so as to control the parking braking of the vehicle.

11. A vehicle controller, comprising a memory and a processor, wherein the memory stores a computer program, characterized in that, When the processor executes the computer program, it implements the steps of the method according to any one of claims 1 to 9.

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