Reversing control method and device in vehicle braking process, new energy vehicle and storage medium

Abstract

The application discloses a reverse control method and device in a vehicle braking process, a new energy vehicle and a storage medium, and relates to the technical field of new energy vehicles. The method comprises the following steps: in the case that the electric braking function of the vehicle is activated, the vehicle braking is controlled based on the electric braking target torque; in the vehicle braking process, if the preset anti-reverse trigger condition is met, the electric braking target torque is cleared, the creep dynamic torque and the hill-hold initial torque are determined based on the slope of the current road surface, and the vehicle speed to the ground is controlled to return from a negative value to 0 based on the creep dynamic torque; the first vehicle speed change rate of the first braking stage is obtained, and the hill-hold initial torque is corrected based on the first vehicle speed change rate to obtain the hill-hold target torque; in the case that the preset parking condition is met, the motor is controlled based on the hill-hold target torque to control the vehicle to complete braking. By adopting the method, the vehicle can be prevented from reversing during braking, thereby improving the safety of the vehicle braking process.

Description

Technical Field

[0001] This application relates to the field of new energy vehicle technology, and in particular to a method, device, new energy vehicle, and storage medium for reversal control during vehicle braking. Background Technology

[0002] With the rapid advancement of new energy vehicle technology, it is essential to improve the safety of new energy vehicles, especially the safety during vehicle parking.

[0003] Currently, vehicle braking control is mainly achieved by the driver operating the braking system. However, in the event of a braking system failure, in order to ensure that the vehicle has sufficient deceleration, the maximum available regenerative torque of the motor is generally used as the target torque for electric braking. This motor output torque, determined based on the target torque for electric braking, may not be accurate enough, which may cause the vehicle to reverse and thus affect braking safety.

[0004] Therefore, improving the safety of vehicle parking has become an urgent problem to be solved. Summary of the Invention

[0005] This application provides a method, device, new energy vehicle, and storage medium for reversing control during vehicle braking, which can improve the safety of vehicle parking.

[0006] In a first aspect, embodiments of this application provide a reversal control method during vehicle braking, the method comprising:

[0007] When the vehicle's electric braking function is activated, the vehicle braking is controlled based on the electric braking target torque.

[0008] During vehicle braking, if the preset anti-reverse triggering condition is met, the electric braking target torque is cleared, the creep dynamic torque and the initial parking torque are determined based on the current road slope, and the vehicle's ground speed is controlled to return from a negative value to a zero value based on the creep dynamic torque.

[0009] The first vehicle speed change rate during the first braking phase is obtained, and the initial parking torque is corrected based on the first vehicle speed change rate to obtain the parking target torque; the first braking phase is the phase in which the vehicle's ground speed regresses from a negative value to a zero value.

[0010] When the preset parking conditions are met, the motor is controlled based on the target torque for parking on the slope to control the vehicle to complete the braking.

[0011] In one embodiment, controlling vehicle braking based on an electric braking target torque includes: when the vehicle's electric braking function is activated, determining an electric braking target torque based on the vehicle's ground speed and the slope of the road surface where the vehicle is located, and controlling vehicle braking based on the electric braking target torque; obtaining a second vehicle speed change rate during a second braking phase; the vehicle speed during the second braking phase is greater than 0 and less than a preset vehicle speed threshold; if the absolute value of the second vehicle speed change rate is greater than a first change rate threshold, obtaining a first correction factor corresponding to the second vehicle speed change rate; the first correction factor is positively correlated with the second vehicle speed change rate, and the first correction factor is less than or equal to 1; correcting the electric braking target torque based on the first correction factor, and continuing to control vehicle braking based on the corrected electric braking target torque.

[0012] In one embodiment, after continuing to control vehicle braking based on the corrected electric braking target torque, the method further includes: obtaining the third vehicle speed change rate of the vehicle in the third braking phase; the third braking phase is after the second braking phase and before the first braking phase; and determining that the preset anti-reverse triggering condition is met when the absolute value of the third vehicle speed change rate is greater than the second change rate threshold, the current gear is a forward gear, and the motor speed is less than the preset motor speed threshold.

[0013] In one embodiment, the method further includes: if the absolute value of the third rate of change is less than or equal to the second rate of change threshold, using the corrected electric braking target torque as the hill-start target torque.

[0014] In one embodiment, the initial parking torque is corrected based on the first vehicle speed change rate to obtain the target parking torque, including: determining a second correction factor corresponding to the first vehicle speed change rate based on a first correspondence; the first correspondence includes a correspondence between multiple vehicle speed change rates and multiple correction factors, and the vehicle speed change rate is negatively correlated with the correction factor; the second correction factor is less than 1; and the initial parking torque is corrected based on the second correction factor to obtain the target parking torque.

[0015] In one embodiment, determining the creep dynamic torque based on the slope of the current road surface includes: determining the current vehicle speed relative to the ground and the creep dynamic torque corresponding to the current road surface slope based on a second correspondence relationship; the second correspondence relationship includes the correspondence between multiple speed-slope combinations and multiple dynamic torques, and the dynamic torque is positively correlated with the vehicle speed in the speed-slope combination and the dynamic torque is positively correlated with the slope in the speed-slope combination.

[0016] In one embodiment, the slope is determined as follows: when the electric braking function is activated, the longitudinal acceleration collected by the vehicle's sensors is acquired, and the actual acceleration of the vehicle is obtained by taking the derivative based on the vehicle's current ground speed; the difference between the longitudinal acceleration and the actual acceleration is obtained; and the slope of the road surface where the vehicle is located is determined by looking up a table based on the difference.

[0017] In one embodiment, the method further includes activating the electric braking function when at least one of the following conditions is met: a first condition where the duration of the key press on the target control of the vehicle is greater than a preset duration threshold; a second condition where the number of key presses on the target control within a preset time period is greater than a preset number threshold; and a third condition where the relative distance between the vehicle and the preceding vehicle is less than a preset relative distance threshold and the relative speed is greater than a preset relative speed threshold.

[0018] Secondly, embodiments of this application provide a reversal control device during vehicle braking, the device comprising:

[0019] The processing module is used to control vehicle braking based on the electric braking target torque when the vehicle's electric braking function is activated.

[0020] The processing module is also used to, during vehicle braking, if the preset anti-reverse triggering condition is met, clear the electric braking target torque, determine the creep dynamic torque and the initial parking torque based on the current road slope, and control the vehicle's ground speed to return from a negative value to a zero value based on the creep dynamic torque.

[0021] The acquisition and correction module is used to acquire the first vehicle speed change rate during the first braking phase, and correct the initial parking torque based on the first vehicle speed change rate to obtain the parking target torque; the first braking phase is the phase in which the vehicle's ground speed regresses from a negative value to a zero value.

[0022] The control module is used to control the motor based on the target torque for parking on a slope, when the preset parking conditions are met, so as to control the vehicle to complete the braking.

[0023] Thirdly, embodiments of this application provide a new energy vehicle, including a memory and a processor. The memory stores a computer program, and the processor executes the computer program to implement the steps of the method described in the first aspect.

[0024] 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 the first aspect above.

[0025] 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 the first aspect above.

[0026] The aforementioned method, device, new energy vehicle, and storage medium for reversal control during vehicle braking: The new energy vehicle (hereinafter referred to as the vehicle) can control vehicle braking based on the electric braking target torque when the vehicle's electric braking function is activated. During vehicle braking, if the preset anti-reversal trigger condition is met, the electric braking target torque is reset to zero. The creep dynamic torque and initial parking torque are determined based on the current road slope. The vehicle's ground speed is controlled to return from a negative value to 0 based on the creep dynamic torque. The first vehicle speed change rate for this braking phase is obtained, and the initial parking torque is corrected based on the first vehicle speed change rate to obtain the parking target torque. When the preset parking conditions are met, the motor is controlled based on the parking target torque to control the vehicle to complete braking. Using this method, when the electric braking function is activated, the vehicle can first control the braking based on the electric braking target torque. If the anti-reverse triggering condition is met during the vehicle braking process, the creep dynamic torque and the initial parking torque are determined in real time based on the current road conditions. The vehicle is then controlled to enter the creep stage (i.e., the stage where the vehicle speed relative to the ground returns from a negative value to 0) based on the creep dynamic torque, and the vehicle speed change rate (first vehicle speed change rate) of the creep stage (i.e., the first braking stage) is obtained. The initial parking torque is corrected based on the vehicle speed change rate of the creep stage. Since both the creep dynamic torque and the initial parking torque are determined in real time based on the road conditions when the vehicle may reverse, and the initial parking torque is also corrected based on the actual vehicle speed change rate of the creep stage to obtain the parking target torque, a more accurate parking target torque can be obtained to prevent or mitigate vehicle braking reversal and improve the safety of the vehicle braking process. Attached Figure Description

[0027] To more clearly illustrate the technical solutions in the embodiments of this application or related technologies, the drawings used in the description of the embodiments of this application or related technologies will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0028] Figure 1 This is a schematic diagram illustrating an application scenario of a reverse control method during vehicle braking provided in an embodiment of this application;

[0029] Figure 2 This is a flowchart illustrating a reversal control method during vehicle braking provided in an embodiment of this application;

[0030] Figure 3 This is a flowchart illustrating another vehicle braking process reversal control method provided in this application embodiment;

[0031] Figure 4This is a schematic diagram of the structure of a reverse control device during vehicle braking provided in an embodiment of this application;

[0032] Figure 5 This is a structural schematic diagram of a new energy vehicle provided in an embodiment of this application. Detailed Implementation

[0033] 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.

[0034] First, a brief explanation of the terms / nouns used in the embodiments of this application will be given.

[0035] 1. Parking Torque

[0036] Parking torque refers to the motor torque when the vehicle is stationary, and it allows the vehicle to remain stationary on various inclines. The primary function of parking torque is not to decelerate the vehicle, but rather to maintain its stillness. It is typically applied when the vehicle speed is low or even close to zero. In some situations, the parking torque can be gradually increased from zero to ensure the vehicle remains as stationary as possible on uphill or downhill roads, thus obtaining the appropriate parking torque. Motor torque, also known as motor output torque, is one of the fundamental parameters of a motor, commonly expressed in Nm (Newton-meters). Motor speed and output torque are generally inversely proportional. For example, during start-up or low-speed operation, the vehicle speed is low, the motor speed is low, and the motor output torque is high to provide sufficient driving force to overcome inertia and resistance. At high speeds, the vehicle speed is high, the motor speed is high, and the output torque is low to meet cruising requirements and improve efficiency.

[0037] 2. Creep dynamic torque

[0038] Creep dynamic torque, also known as deceleration torque or braking torque, is primarily designed for deceleration. It can be dynamically adjusted according to deceleration requirements and can occur at various vehicle speeds, not just when the vehicle is stationary.

[0039] 3. Maximum recoverable torque of the motor

[0040] The maximum recoverable torque of the motor refers to the maximum negative torque generated by the motor during energy recovery. When the driver releases the accelerator pedal or depresses the brake pedal, the motor control generates a negative torque to decelerate the vehicle, thereby achieving energy recovery. The magnitude of this value depends on factors such as the vehicle's control strategy, driving conditions, and the battery's energy storage capacity.

[0041] 4. D gear (Drive gear)

[0042] D gear indicates the vehicle's forward gear. Under normal circumstances, the motor should rotate forward and the motor speed should be positive. If the motor rotates backward, it indicates that the motor is rotating in reverse.

[0043] 5. Vehicle 3D Coordinate System

[0044] In the three-dimensional coordinate system of a car, the three directions are: x (lateral) refers to the left-right direction of the vehicle; y (longitudinal) refers to the front-back direction of the vehicle; and z (vertical) refers to the up-down direction of the vehicle. The velocity of the vehicle is the sum of the lateral velocity and the longitudinal velocity.

[0045] 6. Rate of change of vehicle speed

[0046] In this application, the vehicle speed change rate can be understood as the vehicle acceleration, representing the change in vehicle speed per unit time. That is, the actually calculated vehicle speed change rate can be positive or negative; for example, during deceleration, the vehicle speed change rate is generally negative, while during acceleration, it is generally positive. However, in the embodiments of this application, descriptions related to the magnitude of the vehicle speed change rate, including magnitude comparisons and magnitude correlation descriptions, all discuss its absolute value. Correspondingly, the vehicle speed change rate threshold is always a positive value.

[0047] Optionally, the vehicle speed change rate can be determined by the vehicle controller calculating the vehicle speed at different times based on the wheel speed or the vehicle's drive motor speed; this is not limited here.

[0048] The following is combined Figure 1 This paper introduces the application scenarios of the reverse control method during vehicle braking provided in the embodiments of this application. Please refer to [link to relevant documentation]. Figure 1 , Figure 1 This is a schematic diagram illustrating an application scenario of a reverse control method during vehicle braking provided in an embodiment of this application. For example... Figure 1 As shown, the vehicle 100 includes a cockpit software system 101, an in-vehicle interconnection terminal T-BOX (Telematics BOX) 102, a vehicle controller 103, a conventional braking system 104, a power battery system 105, a motor and a motor controller 106, etc., connected via a bus 107.

[0049] The cockpit software system 101 can be used to control the user interface in the vehicle, including the instrument panel, touch screen, entertainment system and navigation system, providing interactive functions for the driver and passengers.

[0050] As a vehicle's telematics unit, the T-BOX 102 can connect the vehicle interior and the cloud via a communication network, and is responsible for the collection, uploading, and remote control of vehicle data.

[0051] The vehicle controller 103, as the brain of a new energy vehicle, is responsible for coordinating and controlling the operation of components such as batteries, motors, motor controllers, and thermal management systems, and realizing intelligent control of vehicle power distribution, energy management, and overall vehicle functions.

[0052] The conventional braking system 104, including the conventional braking system, mainly controls the deceleration and stopping process of the vehicle by adjusting the clamping torque.

[0053] The power battery system 105 is mainly used to provide the main power source for the car and to provide power to the motor when driving.

[0054] The electric motor and motor controller 106, wherein the electric motor is the core component that converts electrical energy into mechanical energy and provides power when the vehicle is in motion, and the motor controller is responsible for controlling the speed and torque output of the motor. It receives instructions from the vehicle control system and adjusts the operating state of the motor, enabling the motor to achieve acceleration, deceleration, and braking functions. Specifically, the motor controller can change the operating state of the motor by adjusting the current and voltage, determining whether the motor drives the vehicle forward or performs energy recovery.

[0055] The motor and motor controller 106 can also constitute an electric braking system. An electric braking system can be understood as a system that uses the motor controller to adjust the reverse torque of the motor to decelerate or stop the vehicle. In this process, electrical energy is converted into mechanical energy to achieve vehicle braking. The principles involved include energy recovery and braking control. Energy recovery can be understood as the motor controller controlling the motor to generate reverse torque when the vehicle decelerates or stops, converting the vehicle's kinetic energy into electrical energy and storing it back in the battery, thereby extending the driving range. This control method can reduce reliance on traditional mechanical brakes. Correspondingly, the electric braking process can be understood as the process of braking the vehicle primarily through an electric braking system.

[0056] For new energy vehicles, braking can be achieved through a traditional braking system (including a traditional braking system, which mainly controls vehicle deceleration and stopping by adjusting clamping torque). When the traditional braking system fails, to ensure driving safety, the electric braking function can be activated, thereby enabling the vehicle to park through the motor. In the embodiments of this application, when the electric braking function is activated, the vehicle can first control braking based on the electric braking target torque. If the anti-reverse triggering condition is detected during the vehicle braking process, the vehicle enters the creep stage (i.e., the stage where the vehicle speed returns from a negative value to 0) based on the creep dynamic torque, and the vehicle speed change rate during the creep stage is obtained. The initial parking torque is corrected based on the vehicle speed change rate during the creep stage to obtain the parking target torque, and the parking target torque is used to control the vehicle to park on the slope. Since both the creep dynamic torque and the initial parking torque are determined in real time based on the road conditions when the vehicle may reverse, and the initial parking torque is also corrected based on the vehicle speed change rate during the creep phase, a more accurate parking target torque can be obtained. Therefore, in the process of controlling the motor to control the vehicle braking based on the parking target torque, the vehicle braking reversal can be prevented or mitigated, and the safety of the vehicle braking process can be improved.

[0057] The following describes the reverse control method for vehicle braking provided in the embodiments of this application.

[0058] Please see Figure 2 , Figure 2 This is a flowchart illustrating a reversal control method during vehicle braking provided in an embodiment of this application. The method can be executed by the vehicle controller, or by the vehicle controller, the motor, and the motor controller in coordination. For ease of explanation, this application refers to the vehicle controller (e.g., a...) Figure 1 The method of reversing control during vehicle braking is illustrated using the vehicle controller 103 in the vehicle 100 shown as an example. Figure 2 As shown, the reverse control method during vehicle braking may include, but is not limited to, the following steps:

[0059] S201. When the vehicle's electric braking function is activated, control the vehicle braking based on the electric braking target torque.

[0060] In this application, the vehicle may be pre-configured with an electric braking function, as well as the activation conditions for this function. The electric braking function can be understood as the function of controlling vehicle braking based on the aforementioned electric braking system. When activated, this function can replace the traditional braking system to achieve vehicle deceleration and stopping. The activation conditions for the electric braking function may include one or more conditions.

[0061] The motor used in the electric braking function is the same motor used in the normal driving process of the vehicle. It can be understood that the electric braking function and the vehicle driving function are two working modes of the motor. The motor can switch to the electric braking function mode or exit the electric braking function mode and switch to the vehicle driving function mode based on the preset activation and deactivation conditions of the electric braking function.

[0062] Among them, the electric braking target torque can be understood as the motor torque used to decelerate the vehicle when the vehicle's electric braking function is activated.

[0063] In one optional implementation, during vehicle operation, the vehicle controller can acquire multiple status information of the vehicle in real time or periodically, and determine whether the activation conditions of the electric braking function are met based on one or more of the multiple status information. If it is determined that the activation conditions are met, the aforementioned electric braking function can be activated, the electric braking target torque can be determined, and the vehicle braking can be controlled based on the electric braking target torque.

[0064] For example, during vehicle operation, the vehicle controller can acquire multiple status information of the vehicle in real time and match this information with the activation conditions of the electric braking function to determine whether the activation conditions are met. If the vehicle controller determines that the activation conditions are met, it can activate the electric braking function, determine the target electric braking torque, and control the vehicle braking based on the target electric braking torque.

[0065] Optionally, the electric braking target torque can be determined by the vehicle controller through a lookup table based on the vehicle's current speed and the slope of the road surface, or it can be obtained by the vehicle controller by inputting the vehicle's current speed and the slope of the road surface into a pre-built electric braking target torque determination model, etc. There is no limitation here.

[0066] Optionally, the vehicle controller controls vehicle braking based on the electric braking target torque, which can be achieved by adjusting the motor output torque based on the electric braking target torque to control vehicle braking.

[0067] S202. During vehicle braking, if the preset anti-reverse triggering condition is met, the electric braking target torque is cleared, the creep dynamic torque and the initial parking torque are determined based on the current road slope, and the vehicle's ground speed is controlled to return from a negative value to a zero value based on the creep dynamic torque.

[0068] The preset anti-reverse trigger condition can be determined based on the vehicle's historical parking status information. In one optional implementation, during vehicle operation, the vehicle controller can acquire multiple vehicle status information in real time or periodically, and determine whether the preset anti-reverse trigger condition is met based on one or more of these status information. For example, the vehicle controller can determine that the preset anti-reverse trigger condition is met if at least one of the following conditions is satisfied: the absolute value of the vehicle speed change rate during the deceleration phase is greater than a preset vehicle speed change rate threshold (e.g., 2 m / s). 2 ), when the motor speed is less than the preset motor speed threshold (e.g., -200rpm) in D mode.

[0069] In one optional implementation, during vehicle braking, the vehicle controller can acquire multiple status information of the vehicle in real time or periodically. Based on one or more of the multiple status information, it determines whether the preset anti-reverse triggering condition is met. If it is determined that the preset anti-reverse triggering condition has been met, the electric braking target torque can be cleared, the creep dynamic torque and the initial parking torque can be determined based on the current road slope, and converted into control of the vehicle's ground speed from negative to 0 based on the creep dynamic torque.

[0070] In one optional implementation, the vehicle controller determines the creep dynamic torque based on the current road surface gradient. This can be achieved by looking up a table based on the current road surface gradient and the current vehicle speed. The table includes the correspondence between multiple speed-gradient combinations and multiple creep dynamic torques. Optionally, this table can be a pre-set table in the vehicle controller or a pre-set table in a database that the vehicle controller can read; no limitation is imposed here.

[0071] S203. Obtain the first vehicle speed change rate during the first braking phase, and correct the initial parking torque based on the first vehicle speed change rate to obtain the parking target torque; the first braking phase is the phase in which the vehicle's ground speed reverts from a negative value to a zero value.

[0072] Among them, since the first braking stage is the stage in which the vehicle's ground speed returns from a negative value to a zero value, and the vehicle's ground speed returns from a negative value to a zero value based on the vehicle controller's creep dynamic torque control, the first braking stage can also be called the creep stage, and the first speed change rate of the first braking stage can also be called the speed change rate of the creep stage.

[0073] The first rate of change of vehicle speed is a physical quantity used to characterize the change of vehicle speed during the stage when the vehicle's ground speed regresses from a negative value to a zero value.

[0074] S204. When the preset parking conditions are met, the motor is controlled based on the target torque for parking on the slope to control the vehicle to complete braking.

[0075] The preset parking conditions can be one or more conditions, determined based on the vehicle's historical parking information. In one optional implementation, during vehicle operation, the vehicle controller can acquire multiple vehicle status information in real time or periodically, and determine whether the preset parking conditions are met based on one or more of these status information. For example, the vehicle controller can determine the preset parking conditions based on vehicle speed and throttle opening. For instance, it is determined that the preset parking conditions are met if the absolute value of the current vehicle speed relative to the ground is less than a preset speed threshold (e.g., 5 km / h).

[0076] In one alternative implementation, the vehicle controller can control the motor controller in the vehicle to adjust the motor output torque to gradually switch to the parking target torque until the vehicle completes parking.

[0077] In this embodiment, the vehicle controller can control vehicle braking based on the electric braking target torque when the vehicle's electric braking function is activated. During vehicle braking, if the preset anti-reverse triggering condition is met, the electric braking target torque is reset to zero. The creep dynamic torque and the initial parking torque are determined based on the slope of the current road surface. The vehicle's ground speed is controlled to return from a negative value to a zero value based on the creep dynamic torque. The first vehicle speed change rate of the first braking stage is obtained. The initial parking torque is corrected based on the first vehicle speed change rate to obtain the parking target torque. When the preset parking conditions are met, the motor is controlled based on the parking target torque to control the vehicle to complete braking. Using this method, when the electric braking function is activated, the vehicle can first be controlled to brake based on the electric braking target torque. If the anti-reverse triggering condition is met during the vehicle braking process, the creep dynamic torque and the initial parking torque are determined in real time based on the current road conditions. The vehicle is then controlled to enter the creep stage (i.e., the stage where the vehicle speed returns from a negative value to 0) based on the creep dynamic torque, and the vehicle speed change rate (first vehicle speed change rate) of the creep stage (i.e., the first braking stage) is obtained. The initial parking torque is corrected based on the vehicle speed change rate of the creep stage. Since both the creep dynamic torque and the initial parking torque are determined in real time based on the road conditions when the vehicle may reverse, and the initial parking torque is also corrected based on the vehicle speed change rate of the creep stage, a more accurate parking target torque can be obtained to prevent or mitigate vehicle braking reversal and improve the safety of the vehicle braking process.

[0078] In one alternative implementation, Figure 2In the reverse control method during vehicle braking, the vehicle controller controls vehicle braking based on the electric braking target torque. This may include: when the vehicle's electric braking function is activated, determining the electric braking target torque based on the vehicle's ground speed and the slope of the road surface, and controlling vehicle braking based on the electric braking target torque; acquiring the second vehicle speed change rate during the second braking phase; the vehicle speed during the second braking phase being greater than 0 and less than a preset vehicle speed threshold; if the absolute value of the second speed change rate is greater than a first change rate threshold, acquiring a first correction factor corresponding to the second speed change rate; the first correction factor being positively correlated with the second speed change rate, and the first correction factor being less than or equal to 1; correcting the electric braking target torque based on the first correction factor, and continuing to control vehicle braking based on the corrected electric braking target torque.

[0079] In some embodiments, the slope can be determined by the vehicle controller in the following manner: when the electric braking function is activated, the longitudinal acceleration collected by the vehicle's sensors is acquired, and the actual acceleration of the vehicle is obtained by taking the derivative based on the vehicle's current ground speed; the difference between the longitudinal acceleration and the actual acceleration is determined; and the slope of the road surface where the vehicle is located is determined by looking up a table based on the difference.

[0080] The accuracy of the sensor's longitudinal acceleration measurement may be related to its attitude. For example, when the vehicle is on a slope, the sensor mounted on the vehicle may not be horizontal, and the longitudinal acceleration measured by the sensor may not be accurate. Therefore, there may be a certain deviation between this longitudinal acceleration and the actual acceleration calculated based on the vehicle's ground speed. Therefore, based on the difference between the two, the current slope of the vehicle can be calculated.

[0081] Optionally, the vehicle controller can pre-establish a correspondence table (denoted as Correspondence Table 1) based on multiple sets of difference data (the difference between longitudinal acceleration and actual acceleration) and slope input by the user. This Correspondence Table 1 contains the correspondence between multiple sets of difference data and slope. For example, Correspondence Table 1 can be shown in Table 1 below.

[0082] Table 1 Correspondence Table 1

[0083]

[0084] In this table, positive slope values ​​represent uphill slopes, and negative slope values ​​represent downhill slopes. As shown in Table 1, the larger the absolute value of the difference between longitudinal acceleration and actual acceleration, the greater the determined road slope; conversely, the smaller the absolute value of the difference, the smaller the determined road slope. By looking up the table, the current road slope of the vehicle can be determined simply and efficiently.

[0085] Optionally, since both longitudinal acceleration and actual acceleration can be detected or calculated in real time, the vehicle controller can determine the corresponding slope in real time based on the latest determined longitudinal acceleration and actual acceleration, and update the previously determined slope with the latest determined slope to ensure that the recorded slope matches the actual situation better.

[0086] In some embodiments, when the vehicle's electric braking function is activated, the vehicle controller determines the target electric braking torque based on the vehicle's ground speed and the slope of the road surface where the vehicle is located. This can be done by looking up a table based on the vehicle's current ground speed and the slope of the road surface where the vehicle is located.

[0087] Optionally, the vehicle controller can pre-establish a correspondence table (denoted as correspondence table 2) based on the user-input vehicle speed and gradient. This correspondence table 2 contains multiple correspondences between vehicle speed and gradient. For example, the sixth correspondence table can be shown in Table 2 below.

[0088] Table 2 Correspondence Table 2

[0089]

[0090] In Table 2, positive gradient values ​​represent uphill gradients, and negative gradient values ​​represent downhill gradients. As shown in Table 2, when the vehicle is decelerating (vehicle speed relative to the ground is greater than 0), the resistance is lower when the vehicle is going downhill compared to going uphill. Therefore, if the vehicle speed relative to the ground remains constant, the absolute value of the initial electric braking torque required for downhill driving is greater than that for uphill driving. When the vehicle is stationary (i.e., vehicle speed relative to the ground is 0), the greater the gradient, the greater the absolute value of the initial electric braking torque required. By looking up the table, the target electric braking torque corresponding to the activation of the vehicle's electric braking function can be determined simply and efficiently.

[0091] The vehicle controller determines the electric braking target torque based on the vehicle's ground speed and the slope of the road surface, and then controls the vehicle braking based on the electric braking target torque. Subsequently, it can obtain the second vehicle speed change rate during the second braking stage (i.e., the vehicle speed change rate during the process of controlling the vehicle braking based on the electric braking target torque).

[0092] In some embodiments, the vehicle controller can obtain a first correction factor corresponding to the second vehicle speed change rate if the absolute value of the second vehicle speed change rate is greater than a first change rate threshold. The first change rate threshold can also be referred to as the first vehicle speed change rate threshold. For example, assuming the first change rate threshold is 1 m / s... 2 The second vehicle speed change rate is -1.1 m / s 2 In this case, the vehicle controller can determine the absolute value of the second rate of change of vehicle speed as 1.1 m / s. 2Greater than the first rate of change threshold 1m / s 2 At this point, the vehicle controller can obtain the first correction factor corresponding to the second vehicle speed change rate.

[0093] Optionally, the vehicle controller obtains the first correction factor corresponding to the second vehicle speed change rate by looking up a table (denoted as Correspondence Table 3) based on the second vehicle speed change rate. Optionally, Correspondence Table 3 can be a table preset in the vehicle controller, or a table preset in a database that the vehicle controller can read, etc., without limitation here. Correspondence Table 3 includes the correspondence between multiple vehicle speed change rates and multiple correction factors; the second vehicle speed change rate is positively correlated with the correction factor. For example, Correspondence Table 3 can be shown in Table 3 below.

[0094] Table 3 Correspondence Table 3

[0095]

[0096] During the deceleration phase, the larger the absolute value of the rate of change of vehicle speed, the greater the degree of reversal. Therefore, a larger braking torque is required, and a smaller correction factor is needed to correct the target torque for electric braking. As shown in Table 3, the larger the rate of change of vehicle speed, the larger the correction factor needed to correct the target torque for electric braking.

[0097] In some embodiments, the vehicle controller corrects the electric braking target torque based on a first correction factor, which may be the product of the first correction factor and the electric braking target torque as the corrected electric braking target torque.

[0098] In this implementation, when the vehicle's electric braking function is activated, the vehicle controller can determine the target electric braking torque based on the vehicle's speed relative to the ground and the slope of the road surface. It then controls the vehicle's braking based on this target electric braking torque and acquires a second speed change rate during braking. The target electric braking torque is then corrected based on a first correction factor corresponding to this second speed change rate, resulting in a corrected target electric braking torque. By correcting the target electric braking torque based on the speed change rate controlled by the target electric braking torque, a torque more accurately meeting braking requirements can be determined (i.e., the accuracy of the corrected target electric braking torque is higher), thereby reducing the possibility of vehicle reversal during braking.

[0099] In one optional implementation, after the vehicle controller continues to control the vehicle braking based on the corrected electric braking target torque, it can also obtain the third vehicle speed change rate in the third braking stage; the third braking stage is after the second braking stage and before the first braking stage; if the absolute value of the third vehicle speed change rate is greater than the second change rate threshold, the current gear is a forward gear, and the motor speed is less than the preset motor speed threshold, it is determined that the preset anti-reverse triggering condition is met.

[0100] The third braking stage refers to the stage in which vehicle braking is continued based on the corrected electric braking target torque.

[0101] For example, suppose the second rate of change threshold is 1.1 m / s 2 In D mode, the preset motor speed threshold is -200 rpm, and it is assumed that the third vehicle speed change rate is -1.3 m / s. 2 With the current gear in D mode and the motor speed at -300 rpm, the vehicle controller can determine the absolute value of the third vehicle speed change rate as 1.3 m / s². 2 Greater than the second rate of change threshold of 1.1 m / s 2 If the current gear is D and the motor speed is -300rpm less than the preset motor speed threshold of -200rpm, the vehicle controller can determine that the preset anti-reverse trigger condition is met.

[0102] Optionally, the vehicle controller may also use the corrected electric braking target torque as the hill-climbing target torque if the absolute value of the third vehicle speed change rate is less than or equal to the second change rate threshold.

[0103] For example, suppose the second rate of change threshold is 1.1 m / s 2 And assume that the rate of change of the third vehicle speed is -0.5 m / s 2 In this case, the vehicle controller can determine the absolute value of the third vehicle speed change rate as 0.5 m / s. 2 Less than the second rate of change threshold of 1.1 m / s 2 At this point, the vehicle controller can use the corrected electric braking target torque as the hill-start target torque.

[0104] By adopting this implementation method, the vehicle controller can determine whether the preset anti-reverse triggering condition is met after continuing to control the vehicle braking based on the corrected electric braking target torque and then continuing to control the vehicle braking based on the corrected electric braking target torque. This is beneficial to promptly execute the relevant anti-reverse operation when it is determined that the anti-reverse triggering condition is met, thereby preventing the vehicle from reversing.

[0105] In one alternative implementation, Figure 2In the reverse control method during vehicle braking, the vehicle controller corrects the initial parking torque based on the first vehicle speed change rate to obtain the target parking torque. This may include: determining a second correction factor corresponding to the first vehicle speed change rate based on a first correspondence; the first correspondence includes the correspondence between multiple vehicle speed change rates and multiple correction factors; the vehicle speed change rate is negatively correlated with the correction factor; the second correction factor is less than 1; and correcting the initial parking torque based on the second correction factor to obtain the target parking torque.

[0106] Optionally, the first correspondence can be a table preset in the vehicle controller (denoted as the first correspondence table), or a table preset in a database that the vehicle controller can read (denoted as the first correspondence table), etc., without limitation here. The first correspondence table includes the correspondence between multiple vehicle speed change rates and multiple correction factors; the vehicle speed change rate and the correction factor are negatively correlated. For example, the first correspondence table can be shown in Table 4 below.

[0107] Table 4 First Correspondence Table

[0108]

[0109] As shown in Table 4 above, the smaller the rate of change of vehicle speed during the creep phase, the larger the corresponding correction factor used to correct the initial torque for hill-start assist. By looking up the table, the correction factor used to correct the initial torque for hill-start assist can be quickly determined, which helps to improve the efficiency of vehicle braking.

[0110] In some embodiments, the vehicle controller corrects the initial parking torque based on the second correction factor to obtain the target parking torque, which may be the product of the second correction factor and the initial parking torque.

[0111] By using this implementation method, the accuracy of the determined target torque for parking on a slope can be improved by using the rate of change of vehicle speed during the vehicle's creep phase to correct the initial torque for parking on a slope. As a result, in the subsequent process of controlling the vehicle motor to control the vehicle braking based on a more accurate target torque for parking on a slope, the vehicle can be prevented from reversing, thereby improving the safety of the vehicle braking process.

[0112] In one optional implementation, the vehicle controller determines the creep dynamic torque based on the slope of the current road surface, which may include: determining the current vehicle speed relative to the ground and the creep dynamic torque corresponding to the current road surface slope based on a second correspondence; the second correspondence includes the correspondence between multiple speed-slope combinations and multiple dynamic torques, wherein the vehicle speed refers to the speed relative to the ground; the dynamic torque is positively correlated with the vehicle speed in the speed-slope combination, and the dynamic torque is positively correlated with the slope in the speed-slope combination.

[0113] Optionally, the second correspondence can be a table preset in the vehicle controller (denoted as the second correspondence table), or a table preset in a database that the vehicle controller can read (denoted as the second correspondence table), etc., without limitation here. The second correspondence table includes the correspondence between multiple speed-gradient combinations and multiple dynamic torques, where vehicle speed refers to the vehicle speed relative to the ground; dynamic torque is positively correlated with the vehicle speed in the speed-gradient combination, and dynamic torque is positively correlated with the gradient in the speed-gradient combination. For example, the second correspondence table can be shown in Table 5 below.

[0114] Table 5 Second Correspondence Table

[0115]

[0116] In this table, positive slope values ​​represent uphill slopes, and negative slope values ​​represent downhill slopes. Table 5 shows that when the vehicle is in the creeping phase (vehicle speed relative to the ground is less than 0), because the resistance is lower when the vehicle is going downhill compared to going uphill, the absolute value of the creeping dynamic torque required for downhill travel is greater than that for uphill travel, provided the vehicle speed remains constant. When the vehicle is stationary (i.e., vehicle speed relative to the ground is 0), the greater the slope, the greater the absolute value of the required creeping dynamic torque. Using this implementation method, the creeping dynamic torque can be quickly determined by looking up the table.

[0117] In one alternative implementation, Figure 2 In the reverse control method during vehicle braking shown, the vehicle controller can also activate the electric braking function if at least one of the following conditions is met:

[0118] (1) The first condition is that the key press duration of the target control for the vehicle is greater than the preset duration threshold;

[0119] (2) The second condition is that the number of key presses on the target control within a preset time period is greater than the preset key press threshold.

[0120] (3) The third condition is that the relative distance between the vehicle and the vehicle in front is less than the preset relative distance threshold and the relative speed is greater than the preset relative speed threshold.

[0121] The target control can be a physical or virtual button inside the vehicle, and the association between the target button and the electric braking function is predefined. This target button can be a dedicated button for activating or deactivating the electric braking function, or it can be configured to activate or deactivate the electric braking function under specific operating conditions while performing other functions.

[0122] In other words, the vehicle controller can activate the electric braking function if at least one of the first, second, and third conditions is met.

[0123] For example, assuming the preset duration threshold for the target control is 1 second, and the driver presses the button on the target control for 2 seconds, the vehicle controller can determine that the button press duration of 2 seconds exceeds the preset duration threshold of 1 second. In this case, it can be determined that there is an intention to decelerate, and the vehicle controller can activate the electric braking function.

[0124] For example, assuming the preset time period is 1 second, the preset threshold for the number of key presses on the target control within 1 second is 2 times, and the driver presses the target control 3 times within 1 second, then the vehicle controller can determine that the number of key presses on the target control within 1 second is 3 times, which is greater than the preset threshold of 2 times. In this case, it can be determined that there is an intention to decelerate, and at this time, the vehicle controller can activate the electric braking function.

[0125] For example, assuming the preset relative distance threshold is 20m, the preset relative speed threshold is 50km / h, and the relative distance between the vehicle and the vehicle in front is 18m and the relative speed is 55km / h, the vehicle controller can determine that the relative distance between the vehicle and the vehicle in front is 18m, which is less than the preset relative distance threshold of 20m, and the relative speed is 55km / h, which is greater than the preset relative speed threshold of 50km / h. In this case, a collision risk can be determined, and the vehicle controller can activate the electric braking function.

[0126] Optionally, the vehicle controller may also deactivate the electric braking function if at least one of the following conditions is met: (1) the throttle is depressed to a degree greater than a preset ratio; (2) the relative distance between the vehicle and the vehicle in front is greater than a preset distance threshold and the relative speed is less than a preset distance threshold.

[0127] For example, assuming the accelerator pedal is depressed to 30% and the preset ratio is 20%, the vehicle controller can determine that the accelerator pedal depression of 30% is greater than the preset ratio of 20%. In this case, it can be determined that there is an intention to accelerate. At this time, the vehicle controller can disengage the electric braking function.

[0128] For example, assuming the preset relative distance threshold is 30m, the preset relative speed threshold is 20km / h, and the relative distance between the vehicle and the vehicle in front is 31m and the relative speed is 8km / h, the vehicle controller can determine that the relative distance between the vehicle and the vehicle in front of it is 31m, which is greater than the preset relative distance threshold of 30m, and the relative speed is 8km / h, which is less than the preset relative speed threshold of 10km / h. In this case, it can be determined that there is no risk of collision, and the vehicle controller can then deactivate the electric braking function.

[0129] By adopting this implementation method, the vehicle controller can determine under what circumstances the electric braking function is activated. Thus, when the triggering conditions for activating the electric braking function are detected, the electric braking function can be activated in a timely manner, which is beneficial for timely control of vehicle braking.

[0130] The following is combined Figure 3 This paper describes the overall process of the vehicle braking process reversal control method provided in the embodiments of this application. Please refer to [link to relevant documentation]. Figure 3 , Figure 3 This is a flowchart illustrating another method for reversing control during vehicle braking provided in an embodiment of this application. This method can be executed by the vehicle controller. Figure 3 As shown, the reverse control method during the vehicle braking process may include, but is not limited to, the following steps.

[0131] S301: Real-time monitoring of vehicle motor speed, button status, gear position, longitudinal acceleration, and throttle opening.

[0132] S302. Calculate the current vehicle speed based on the motor speed.

[0133] In one alternative implementation, the vehicle controller may use the following formula when calculating the vehicle speed based on the motor speed.

[0134]

[0135] In formula (1), V represents vehicle speed (unit: km / h); n represents motor speed (unit: rpm); r represents tire radius (unit: meter); i represents speed ratio; and μ is the conversion coefficient from speed to vehicle speed.

[0136] Based on the vehicle speed and the current direction of travel, the vehicle speed relative to the ground can be obtained. The direction of travel can be forward or in the opposite direction; forward refers to the direction the vehicle is facing. In some possible embodiments, the direction of travel can be determined by the sign of the motor speed, i.e., forward and reverse rotation. For example, a positive motor speed corresponds to a forward direction of travel, and a negative motor speed corresponds to a reverse direction of travel. For example, V... Direction Indicates the vehicle's direction of travel. When the motor speed is less than -50 rpm and the direction of travel is reversed, then V... Direction Equal to -1, when the motor speed is greater than 50 rpm, the direction of travel is positive, V Direction It equals 1. Of course, the motor speed threshold here can also take other values. In order to ensure the accuracy of the judgment, the threshold is generally not close to 0.

[0137] S303. Based on longitudinal acceleration and ground speed, determine the slope of the road surface where the vehicle is located.

[0138] In one optional implementation, the vehicle controller calculates the gradient based on the longitudinal acceleration and the vehicle speed relative to the ground, which may include: differentiating the vehicle speed relative to the ground to obtain the actual acceleration of the vehicle; determining the difference between the longitudinal acceleration and the actual acceleration; and determining the gradient of the road surface where the vehicle is located by looking up the difference in a table.

[0139] Optionally, for a detailed description of this implementation method, please refer to the description of the slope determination method in the preceding text, which will not be repeated here.

[0140] S304. Determine the electric braking function flag based on button status, throttle opening, relative distance, and relative speed.

[0141] For example, the vehicle controller may also activate the electric braking function if at least one of the following conditions is met: (1) the duration of the key press on the target control exceeds a preset duration threshold of 1 second; (2) the number of key presses on the target control within a preset time period (1 second) exceeds a preset key press threshold of 2; (3) the relative distance between the vehicle and the vehicle in front is less than a preset relative distance threshold of 20m and the relative speed is greater than a preset relative speed threshold of 50km / h.

[0142] For example, the vehicle controller may also deactivate the electric braking function if at least one of the following conditions is met: (1) the accelerator pedal opening is greater than 20%; (2) the relative distance between the vehicle and the vehicle in front is greater than a preset relative distance threshold of 30m and the relative speed is less than a preset relative speed threshold of 20km / h.

[0143] S305. Based on the electric braking function flag, vehicle speed relative to ground, gradient, and the maximum available recovery torque of the motor, determine the target torque for electric braking.

[0144] Optionally, when the electric braking function flag is activated, the vehicle controller can determine the initial target torque for electric braking by referring to a table (as shown in Table 2 above) with the vehicle speed relative to the ground as the horizontal axis and the gradient as the vertical axis. The higher the vehicle speed relative to the ground and the smaller the gradient, the greater the determined target torque for electric braking. The target torque for electric braking must be within the range of the maximum recoverable torque available from the motor.

[0145] When the vehicle speed is close to 0, in order to ensure that the vehicle can remain stationary on different slopes, the target torque of the electric brake needs to be set within an appropriate range.

[0146] S306. Control vehicle braking based on electric braking target torque, and during the braking process, determine the corrected electric braking target torque based on the vehicle speed change rate and the electric braking target torque.

[0147] For example, the vehicle controller can determine the degree of reversal based on the vehicle speed change rate. When the vehicle speed is less than a set threshold of 0.5 km / h, it uses the vehicle speed change rate as the horizontal axis to look up a table (as shown in Table 3 above) to determine the first correction factor used to correct the electric braking target torque. If the vehicle speed change rate is larger, it indicates a greater degree of reversal, and the electric braking target torque needs to be corrected. The corrected electric braking target torque can be the product of the electric braking target torque and the first correction factor.

[0148] S307, continue to control vehicle braking based on the corrected electric braking target torque.

[0149] Optionally, after the vehicle controller continues to control the vehicle braking based on the corrected electric braking target torque, if the rate of change of vehicle speed is low enough, the torque can bring the vehicle to a stop. In this case, the corrected electric braking target torque can be used as the hill-climbing target torque. If the rate of change of vehicle speed is still too large, the vehicle will continue to move in the opposite direction. The correction factor will continue to apply until the anti-reverse flag is triggered. In other words, if the rate of change of vehicle speed is still too large and the anti-reverse flag is not triggered, the vehicle controller can further correct the corrected electric braking target torque based on the correction factor corresponding to the rate of change of vehicle speed during this braking phase.

[0150] S308: Determine the anti-reverse flag position based on motor speed and gear.

[0151] For example, the vehicle controller can perform anti-reverse protection under the following conditions when the absolute value of the rate of change of vehicle speed during the braking phase, based on the corrected electric braking target torque, is greater than a preset rate of change threshold: when the gear is in D, the motor speed is less than the set threshold - 200 rpm. In other words, the vehicle controller can activate the anti-reverse flag when the absolute value of the rate of change of vehicle speed during the braking phase, based on the corrected electric braking target torque, is greater than the preset rate of change threshold, and when the gear is in D, the motor speed is less than the set threshold - 200 rpm.

[0152] S309. Based on the anti-reverse sign position, vehicle speed change rate, and vehicle speed, calculate the creep dynamic torque and the initial torque for parking on the slope, and control the vehicle's ground speed to regress from a negative value to a zero value based on the creep dynamic torque.

[0153] The basic principle is as follows:

[0154] When the anti-reverse flag is activated, it indicates that the vehicle's reverse movement is too great. The corrected electric braking target torque must be immediately reset to zero, and to prevent loss of vehicle control, the creep dynamic torque must be calculated based on the current slope. Optionally, the vehicle controller can calculate the creep dynamic torque by referring to a table (as shown in Table 5) with vehicle speed as the horizontal axis and slope as the vertical axis. The lower the vehicle speed relative to the ground and the smaller the slope, the smaller the determined creep dynamic torque.

[0155] Optionally, the initial parking torque can be determined by the vehicle controller using a lookup table based on the vehicle speed and slope, or it can be obtained by the vehicle controller inputting the vehicle speed and slope into a pre-built initial parking torque determination model. No limitation is imposed here.

[0156] S310. The initial torque for parking on the slope is corrected based on the correction factor corresponding to the rate of change of vehicle speed during the creep stage, so as to obtain the target torque for parking on the slope.

[0157] Optionally, the vehicle controller can determine the correction factor corresponding to the vehicle speed change rate during the creep phase by referring to a table (such as Table 4 above).

[0158] Optionally, the vehicle controller corrects the initial parking torque based on the correction factor corresponding to the vehicle speed change rate during the creep phase to obtain the target parking torque. Alternatively, the target parking torque can be obtained by multiplying the correction factor corresponding to the vehicle speed change rate during the creep phase and the initial parking torque.

[0159] S311. When the preset parking conditions are met, the motor is controlled based on the target torque for parking on the slope to control the vehicle to complete the braking.

[0160] In this embodiment, the vehicle controller can determine the activation flag of the electric braking function based on the button status, throttle opening, relative distance, and relative speed; determine the electric braking target torque based on the electric braking function flag, vehicle speed relative to ground, slope, and the maximum available regenerative torque of the motor; control the vehicle braking based on the electric braking target torque, and during this braking process, determine the corrected electric braking target torque based on the vehicle speed change rate and the electric braking target torque; continue to control the vehicle braking based on the corrected electric braking target torque; determine the anti-reverse flag based on the motor speed and gear; calculate the creep dynamic torque and the initial parking torque based on the anti-reverse flag, vehicle speed change rate, and vehicle speed, and control the vehicle speed relative to ground to return from a negative value to a zero value based on the creep dynamic torque; correct the initial parking torque based on the correction factor corresponding to the vehicle speed change rate during the creep stage to obtain the parking target torque; finally, under the condition that the preset parking conditions are met, control the motor based on the parking target torque until the vehicle completes parking. In this way, when the electric braking function is activated, the vehicle controller can first control the vehicle braking based on the electric braking target torque. If the anti-reverse triggering condition is met during the vehicle braking process, the creep dynamic torque and the initial parking torque are determined in real time based on the current road conditions. The vehicle is then controlled to enter the creep stage (i.e., the stage where the vehicle speed relative to the ground returns from a negative value to 0) based on the creep dynamic torque, and the vehicle speed change rate (first vehicle speed change rate) of the creep stage (i.e., the first braking stage) is obtained. The initial parking torque is corrected based on the vehicle speed change rate of the creep stage. Since both the creep dynamic torque and the initial parking torque are determined in real time based on the road conditions when the vehicle may reverse, and the initial parking torque is also corrected based on the actual vehicle speed change rate of the creep stage to obtain the parking target torque, a more accurate parking target torque can be obtained to prevent or mitigate the vehicle's braking reversal and improve the safety of the vehicle braking process.

[0161] 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.

[0162] Based on the same inventive concept, this application also provides a vehicle braking process reversal control device for implementing the above-described vehicle braking process reversal control method. The solution provided by this device is similar to the solution described in the above method; therefore, the specific limitations of one or more vehicle braking process reversal control device embodiments provided below can be found in the above-described limitations of the vehicle braking process reversal control method, and will not be repeated here.

[0163] Please see Figure 4 , Figure 4 This is a schematic diagram of the structure of a reverse control device during vehicle braking provided in an embodiment of this application. Figure 4 As shown, the reverse control device during vehicle braking may include, but is not limited to:

[0164] Processing module 401 is used to control vehicle braking based on electric braking target torque when the vehicle's electric braking function is activated.

[0165] The processing module 401 is also used to, during vehicle braking, if the preset anti-reverse triggering condition is met, clear the electric braking target torque, determine the creep dynamic torque and the initial parking torque based on the slope of the current road surface, and control the vehicle's ground speed to return from a negative value to a zero value based on the creep dynamic torque.

[0166] The acquisition and correction module 402 is used to acquire the first vehicle speed change rate during the first braking phase, and correct the initial parking torque based on the first vehicle speed change rate to obtain the parking target torque; the first braking phase is the phase in which the vehicle's ground speed reverts from a negative value to a zero value.

[0167] The control module 403 is used to control the motor based on the target torque for parking on a slope, when the preset parking conditions are met, so as to control the vehicle to complete the braking.

[0168] In one embodiment, when the processing module 401 controls vehicle braking based on the electric braking target torque, it is specifically used to: determine the electric braking target torque based on the vehicle's ground speed and the slope of the road surface where the vehicle is located when the vehicle's electric braking function is activated, and control vehicle braking based on the electric braking target torque; obtain the second vehicle speed change rate in the second braking stage; the vehicle speed in the second braking stage is greater than 0 and less than a preset vehicle speed threshold; if the absolute value of the second vehicle speed change rate is greater than a first change rate threshold, obtain a first correction factor corresponding to the second vehicle speed change rate; the first correction factor is positively correlated with the second vehicle speed change rate, and the first correction factor is less than or equal to 1; correct the electric braking target torque based on the first correction factor, and continue to control vehicle braking based on the corrected electric braking target torque.

[0169] In one embodiment, the device may further include an acquisition module and a determination module. After the processing module 401 continues to control the vehicle braking based on the corrected electric braking target torque, the acquisition module is used to acquire the third vehicle speed change rate of the vehicle in the third braking phase; the third braking phase is after the second braking phase and before the first braking phase; the determination module is used to determine that the preset anti-reverse triggering condition is met when the absolute value of the third vehicle speed change rate is greater than the second change rate threshold, the current gear is a forward gear, and the motor speed is less than the preset motor speed threshold.

[0170] In one embodiment, the determining module is further configured to use the corrected electric braking target torque as the hill-start target torque if the absolute value of the third vehicle speed change rate is less than or equal to the second change rate threshold.

[0171] In one embodiment, when the acquisition and correction module 402 is used to correct the initial parking torque based on the first vehicle speed change rate to obtain the target parking torque, it is specifically used to: determine the second correction factor corresponding to the first vehicle speed change rate based on the first correspondence relationship; the first correspondence relationship includes the correspondence between multiple vehicle speed change rates and multiple correction factors, and the absolute value of the vehicle speed change rate is negatively correlated with the correction factor; the second correction factor is less than 1; and correct the initial parking torque based on the second correction factor to obtain the target parking torque.

[0172] In one embodiment, when the processing module 401 determines the creep dynamic torque based on the slope of the current road surface, it is specifically used to: determine the current vehicle speed relative to the ground and the creep dynamic torque corresponding to the current road surface slope based on the second correspondence relationship; the second correspondence relationship includes the correspondence relationship between multiple speed-slope combinations and multiple dynamic torques, and the dynamic torque is positively correlated with the vehicle speed in the speed-slope combination and the dynamic torque is positively correlated with the slope in the speed-slope combination.

[0173] In one embodiment, the device may further include an electric braking function management module, which is used to activate the electric braking function when at least one of the following conditions is met: a first condition where the key press duration of the target control on the vehicle is greater than a preset duration threshold; a second condition where the number of key presses on the target control within a preset time period is greater than a preset number threshold; and a third condition where the relative distance between the vehicle and the vehicle in front is less than a preset relative distance threshold and the relative speed is greater than a preset relative speed threshold.

[0174] The modules in the aforementioned vehicle braking reversal control device can be implemented entirely or partially through software, hardware, or a combination thereof. These modules can be embedded in or independent of the processor in a computer device, or stored in the memory of the vehicle control device as software, so that the processor can call and execute the corresponding operations of each module.

[0175] In one exemplary embodiment, a new energy vehicle is provided, the internal structure of which can be shown in the following diagram. Figure 5 As shown, the new energy vehicle includes a processor, memory, input / output interface, communication interface, display unit, and input device. The processor, memory, and input / output interface are connected via a system bus, and the communication interface, display unit, and input device are also connected to the system bus via the input / output interface. The processor provides computing and control capabilities. The memory includes non-volatile storage media and internal memory. The non-volatile storage media stores the operating system and computer programs. The internal memory provides an environment for the operation of the operating system and computer programs in the non-volatile storage media. The input / output interface is 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 reversing control method during vehicle braking. The display unit is used to form a visually visible image and can be a display screen, projection device, or virtual reality imaging device. The display screen can be an LCD screen or an e-ink screen. The input device of the new energy vehicle can be a touch layer covering the display screen, or it can be a button, trackball, or touchpad installed in the new energy vehicle.

[0176] Those skilled in the art will understand that Figure 5 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 new energy vehicle to which the present application is applied. A specific new energy vehicle may include more or fewer components than those shown in the figure, or combine certain components, or have different component arrangements.

[0177] In one exemplary embodiment, this application provides a new energy vehicle, including a memory and a processor, wherein the memory stores a computer program; when the processor executes the computer program, it implements the steps in the above-described vehicle braking process reversal control method.

[0178] In one exemplary embodiment, this application provides a computer-readable storage medium having a computer program stored thereon. When executed by a processor, the computer program implements the steps in the reversal control methods described above for vehicle braking processes.

[0179] In one exemplary embodiment, this application provides a computer program product, including a computer program. When executed by a processor, the computer program implements the steps in the reversal control methods described above for vehicle braking processes.

[0180] It should be noted that the data involved in this application (including but not limited to electric braking target torque, creep dynamic torque, initial parking torque, first speed change rate, parking target torque, etc.) 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.

[0181] Those skilled in the art will understand that all or part of the processes in the methods of 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, and when executed, it can include the processes of the embodiments of the above methods. Any references to memory, databases, or other media used in the embodiments provided in this application can include at least one of non-volatile memory 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, artificial intelligence (AI) processors, etc., and are not limited to these.

[0182] 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 application.

[0183] 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 patent 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 of reverse control in a vehicle braking process, characterized by, The method comprises: In the case that the electric braking function of the vehicle is activated, the vehicle is controlled based on an electric braking target torque; During the braking of the vehicle, if a preset anti-reverse rotation trigger condition is met, the electric braking target torque is cleared, a creep dynamic torque and a hill-hold initial torque are determined based on the slope of the current road, and the vehicle speed of the vehicle is controlled to return from a negative value to 0 based on the creep dynamic torque; A first vehicle speed change rate in a first braking stage is obtained, and the hill-hold initial torque is corrected based on the first vehicle speed change rate to obtain a hill-hold target torque; The first braking stage is a stage in which the vehicle speed of the vehicle returns from a negative value to 0; In the case that a preset parking condition is met, the motor is controlled based on the hill-hold target torque to control the vehicle to complete braking.

2. The method of claim 1, wherein, The method comprises: In the case that the electric braking function of the vehicle is activated, the vehicle is controlled based on an electric braking target torque; A second vehicle speed change rate of the vehicle in a second braking stage is obtained; the vehicle speed in the second braking stage is greater than 0 and less than a preset vehicle speed threshold; In the case that the absolute value of the second vehicle speed change rate is greater than a first change rate threshold, a first correction factor corresponding to the second vehicle speed change rate is obtained; the first correction factor is less than 1; The electric braking target torque is corrected based on the first correction factor, and the vehicle is controlled based on the corrected electric braking target torque.

3. The method of claim 2, wherein, After the vehicle is controlled based on the corrected electric braking target torque, the method further comprises: A third vehicle speed change rate of the vehicle in a third braking stage is obtained; the third braking stage is after the second braking stage and before the first braking stage; In the case that the absolute value of the third vehicle speed change rate is greater than a second change rate threshold, the current gear is a forward gear, and the motor speed is less than a preset motor speed threshold, it is determined that the preset anti-reverse rotation trigger condition is met.

4. The method of claim 3, wherein, The method further comprises: In the case that the absolute value of the third vehicle speed change rate is less than or equal to the second change rate threshold, the corrected electric braking target torque is taken as the hill-hold target torque.

5. The method of claim 1, wherein, The method further comprises: A second correction factor corresponding to the first vehicle speed change rate is determined based on a first corresponding relationship; the first corresponding relationship comprises a corresponding relationship between a plurality of vehicle speed change rates and a plurality of correction factors; the second correction factor is less than 1; The hill-hold initial torque is corrected based on the second correction factor to obtain a hill-hold target torque.

6. The method of claim 1, wherein, The creep dynamic torque is determined based on the slope of the current road, which comprises: A creep dynamic torque corresponding to the current vehicle speed and the slope of the current road is determined based on a second corresponding relationship; the second corresponding relationship comprises a corresponding relationship between a plurality of vehicle speed and slope combinations and a plurality of dynamic torques.

7. The method according to any one of claims 1 to 6, characterized in that, The method further comprises: The electric braking function is activated when at least one of the following conditions is met: A first condition that a key pressing duration of a target control of the vehicle is greater than a preset duration threshold; A second condition that a key pressing frequency of the target control within a preset time period is greater than a preset frequency threshold; A third condition that a relative distance between the vehicle and a preceding vehicle is less than a preset relative distance threshold, and a relative speed is greater than a preset relative speed threshold.

8. A reverse control device during vehicle braking, characterized in that, The device comprises: A processing module configured to control the vehicle braking based on an electric braking target torque when the electric braking function of the vehicle is activated; The processing module is further configured to, if a preset anti-reverse rotation trigger condition is met during the vehicle braking, clear the electric braking target torque, determine a creep dynamic torque and a hill-hold initial torque based on a slope of a current road surface, and control the ground speed of the vehicle to return from a negative value to 0 based on the creep dynamic torque; An acquisition and correction module configured to acquire a first vehicle speed change rate in a first braking stage, and correct the hill-hold initial torque based on the first vehicle speed change rate to obtain a hill-hold target torque; the first braking stage is a stage in which the ground speed of the vehicle returns from a negative value to 0; A control module configured to control the motor based on the hill-hold target torque to control the vehicle to complete braking when a preset parking condition is met. 9.A new energy vehicle, comprising a memory and a processor, wherein the memory stores a computer program, and the computer program comprises the following steps of: The processor executes the computer program to implement the steps of the method of any one of claims 1 to 7.

10. A computer-readable storage medium having stored thereon a computer program, characterized in that, The computer program is executed by the processor to implement the steps of the method of any one of claims 1 to 7.

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