Vehicle parking control method and device, new energy vehicle and storage medium

Abstract

The invention discloses a vehicle parking control method and device, a new energy vehicle and a storage medium, and relates to the technical field of new energy vehicles. The method comprises the following steps: under the condition that an electric braking function of a vehicle is activated, determining a hill-holding initial torque; the slope sliding vehicle speed change rate and the slope sliding frequency when the vehicle slides on the current road surface are obtained; target correction factors corresponding to the slope sliding vehicle speed change rate and the slope sliding times are obtained, the slope parking initial torque is corrected based on the target correction factors, and slope parking target torque is obtained; and under the condition that the preset parking condition is met, the motor is controlled based on the slope parking target torque until the vehicle is parked. By adopting the method, the safety of the vehicle in the parking process can be improved.

Description

Technical Field

[0001] The present application relates to the technical field of new energy vehicles, and in particular to a vehicle parking control method, device, new energy vehicle and storage medium. Background Art

[0002] As new energy vehicle technologies are updated day by day, it is very necessary to improve the safety of new energy vehicles, especially the safety of the vehicle's parking process. In order to achieve vehicle parking on a slope, the vehicle's Electronic Stability Control (ESC) module is usually required to control the motor to achieve parking on a slope. However, in the process of controlling the motor to achieve parking on a slope, if the parking torque is not accurate enough, the vehicle may slip, which leads to low safety during the vehicle parking process.

[0003] Therefore, how to improve the safety of the vehicle parking process has become an issue that needs to be solved urgently. Summary of the invention

[0004] The embodiments of the present application provide a vehicle parking control method, device, new energy vehicle and storage medium, which can improve the safety of the vehicle parking process.

[0005] In a first aspect, an embodiment of the present application provides a vehicle parking control method, the method comprising:

[0006] Determining the initial holding torque when the electric braking function of the vehicle is activated;

[0007] Obtain the speed change rate and number of times the vehicle slides downhill when sliding downhill on the current road surface;

[0008] Obtaining the target correction factor corresponding to the speed change rate of the vehicle rolling down the slope and the number of times the vehicle rolls down the slope, and correcting the initial torque for holding the slope based on the target correction factor to obtain the target torque for holding the slope;

[0009] When the preset parking conditions are met, the motor is controlled based on the hill-parking target torque until the vehicle is parked.

[0010] In one embodiment, when the electric braking function of the vehicle is activated, the initial torque for holding the vehicle on a hill is determined, including: when the electric braking function of the vehicle is activated, if a preset slope update condition is met, the slope of the road surface on which the vehicle is currently located is determined based on the vehicle speed change rate, current wheel-end torque, vehicle mass and current ground speed within a preset time period, and the previously determined slope is updated based on the slope; based on the updated slope, the initial torque for holding the vehicle on a hill is determined.

[0011] In one of the embodiments, the method also includes: when the electric braking function of the vehicle is activated, obtaining the vehicle speed change rate and the current wheel-end torque; derivatizing the vehicle speed change rate to obtain the vehicle's speed jerk; and determining that the preset slope update condition is met when the absolute value of the vehicle speed jerk is less than a preset jerk threshold, the duration of the vehicle speed jerk is greater than or equal to the preset duration, the absolute value of the difference between the target wheel-end torque and the current wheel-end torque is less than the preset threshold, the current wheel-end torque is less than the preset torque threshold, and the vehicle's current ground speed is greater than the preset speed threshold.

[0012] In one embodiment, the slope of the road surface on which the vehicle is currently located is determined based on the vehicle speed change rate, current wheel-end torque, vehicle mass and current ground speed within a preset time period, including: based on the vehicle speed change rate and current wheel-end torque within the preset time period, looking up a table to obtain an initial slope of the road surface on which the vehicle is currently located; based on a first correction factor corresponding to the vehicle mass, correcting the initial slope to obtain a corrected slope; based on a second correction factor corresponding to the current ground speed, correcting the corrected slope to obtain the slope of the road surface on which the vehicle is currently located.

[0013] In one of the embodiments, the current vehicle speed relative to the ground is determined by: obtaining the vehicle's current motor speed, tire radius, speed ratio, and a conversion coefficient from motor speed to vehicle speed; determining the vehicle's speed based on the current motor speed, tire radius, speed ratio, and conversion coefficient; determining the current vehicle speed relative to the ground based on the vehicle speed and the vehicle's driving direction.

[0014] In one of the embodiments, obtaining the target correction factor corresponding to the speed change rate of the vehicle rolling down the slope and the number of times the vehicle rolls down the slope includes: determining the target correction factor corresponding to the speed change rate of the vehicle rolling down the slope and the number of times the vehicle rolls down the slope based on a preset corresponding relationship; the preset corresponding relationship includes a corresponding relationship between a combination of multiple speed change rates of the vehicle rolling down the slope and the number of times the vehicle rolls down the slope and multiple correction factors; the correction factor is positively correlated with the speed change rate of the vehicle rolling down the slope in the combination, and the correction factor is positively correlated with the number of times the vehicle rolls down the slope in the combination.

[0015] In one embodiment, the method also includes: activating the electric braking function when at least one of the following conditions is met: a first condition that the key pressing duration for the target control of the vehicle is greater than a preset duration threshold; a second condition that the number of key pressings for the target control within a preset time period is greater than a preset number threshold; a third condition that 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.

[0016] In a second aspect, an embodiment of the present application provides a vehicle parking control device, the device comprising:

[0017] A determination module, used to determine a hill-holding initial torque when an electric brake function of the vehicle is activated;

[0018] An acquisition module is used to obtain the speed change rate and the number of times the vehicle slides down the slope when sliding down the slope on the current road surface;

[0019] An acquisition and correction module is used to acquire a target correction factor corresponding to a speed change rate of a vehicle rolling down a slope and a number of times the vehicle rolls down a slope, and to correct an initial torque for holding a slope based on the target correction factor to obtain a target torque for holding a slope;

[0020] The torque control module is used to control the motor based on the hill-parking target torque until the vehicle completes parking when the preset parking conditions are met.

[0021] In a third aspect, an embodiment of the present application provides a new energy vehicle, including a memory and a processor, wherein the memory stores a computer program, and when the processor executes the computer program, the steps of the method described in the first aspect are implemented.

[0022] In a fourth aspect, the present application further provides a computer-readable storage medium having a computer program stored thereon, which implements the steps of the method described in the first aspect when the computer program is executed by a processor.

[0023] In a fifth aspect, the present application further provides a computer program product, including a computer program, which, when executed by a processor, implements the steps of the method described in the first aspect above.

[0024] The above-mentioned vehicle parking control method, device, new energy vehicle and storage medium, the new energy vehicle (hereinafter referred to as the vehicle) can determine the initial holding torque when the electric braking function of the vehicle is activated; obtain the speed change rate and the number of times the vehicle rolls down the slope when the vehicle rolls down the slope on the current road surface; obtain the target correction factor corresponding to the speed change rate and the number of times the vehicle rolls down the slope, and correct the initial holding torque based on the target correction factor to obtain the holding torque; when the preset parking conditions are met, control the motor based on the holding torque until the vehicle completes parking. By adopting this method, the vehicle can correct the initial holding torque based on the target correction factor corresponding to the rolling speed change rate and the number of rolling times when the vehicle rolls down the slope on the current road surface when the electric braking function is activated, so as to obtain the holding target torque, and control the motor based on the holding target torque when the preset parking conditions are met until the vehicle completes parking. In this way, during the parking process of the vehicle, the initial holding torque is corrected based on the target correction factor corresponding to the actual driving situation of the vehicle (the rolling speed change rate and the number of rolling times when the vehicle rolls down the slope on the current road surface), so that the corrected holding target torque can be more in line with the actual parking demand, that is, the corrected holding target torque has higher accuracy, thereby avoiding the phenomenon of the vehicle rolling due to errors in the initial value of the holding torque and the inability to match the actual parking demand of the vehicle, and further improving the safety of the vehicle during parking. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] In order to more clearly illustrate the technical solutions in the embodiments of the present application or related technologies, the drawings required for use in the embodiments of the present application or related technical descriptions will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without paying creative work.

[0026] Figure 1 It is a schematic diagram of an application scenario of a vehicle parking control method provided by an embodiment of the present application;

[0027] Figure 2 is a flow chart of a vehicle parking control method provided by an embodiment of the present application;

[0028] Figure 3 is a flow chart of another vehicle parking control method provided by an embodiment of the present application;

[0029] Figure 4 is a structural schematic diagram of a vehicle parking control device provided in an embodiment of the present application;

[0030] Figure 5 It is a structural schematic diagram of a new energy vehicle provided in an embodiment of the present application. DETAILED DESCRIPTION

[0031] In order to make the purpose, technical solution and advantages of the present application more clearly understood, the present application is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0032] First, the terms / nouns involved in the embodiments of the present application are briefly explained.

[0033] 1. Holding torque

[0034] Hill-holding torque refers to the motor torque when the vehicle is static, and the hill-holding torque can make the vehicle stationary on different slopes. The main function of the hill-holding torque is not to slow down the vehicle, but to maintain the vehicle's stillness. It is usually applied when the vehicle speed is low or even close to 0. In some cases, the hill-holding torque can be continuously increased from 0 to ensure that the vehicle remains as still as possible on uphill or downhill roads, thereby obtaining a suitable hill-holding target torque. Among them, the motor torque can also be called the motor output torque, which is one of the basic parameters of the motor, commonly used in Nm (Newton-meter). The motor speed and output torque are usually inversely proportional. For example, at starting or low speed, 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 speed, the vehicle speed is high, the motor speed is high, and the output torque is low to meet cruising needs while improving efficiency.

[0035] 2. Maximum available regenerative torque of the motor

[0036] The maximum available regenerative torque of the motor refers to the maximum value of the negative torque generated by the motor during energy recovery. When the driver releases the accelerator pedal or steps on the brake pedal, the motor control will generate a negative torque to slow down the car and achieve energy recovery. The value depends on factors such as the vehicle's control strategy, driving status, and the battery's energy storage capacity.

[0037] 3. Wheel end torque

[0038] Wheel-end torque refers to the torque applied to the wheels of a car, which is usually transmitted to the wheels by the electric motor through the transmission system. It directly affects the acceleration performance, traction and braking effect of the vehicle. In new energy vehicles, wheel-end torque is an important indicator for evaluating power and function, and can affect endurance and energy efficiency. Reasonable control of wheel-end torque can help improve driving experience and improve energy efficiency.

[0039] 4. Vehicle speed jerk

[0040] Vehicle jerk is the rate of change of acceleration, which is a physical quantity that describes how fast acceleration changes over time.

[0041] 5. D (Drive)

[0042] The D gear represents the vehicle's forward gear. Under normal circumstances, the motor should rotate forward at this time and the motor speed should be a positive value; if the motor rotates backward at this time, it indicates that the motor is reversed.

[0043] 6. Automobile 3D coordinate system

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

[0045] Combine the following Figure 1 , introduces the application scenario of the vehicle parking control method provided by the embodiment of the present application. Figure 1 , Figure 1 Schematic diagram of an application scenario of a vehicle parking control method provided by an embodiment of the present application. Figure 1 As shown, the vehicle 100 includes a cockpit software system 101, an on-board interconnection terminal T-BOX (TelematicsBOX) 102, a vehicle controller 103, a traditional braking system 104, a power battery system 105, a motor and a motor controller 106, etc. connected via a bus 107.

[0046] The cockpit software system 101 can be used to control the user interface in the car, including the instrument panel, touch screen, entertainment system and navigation system, and provide interactive functions for the driver and passengers.

[0047] As the vehicle's telematics unit, T-BOX 102 can connect the vehicle and the cloud through a communication network and is responsible for collecting, uploading and remotely controlling vehicle data.

[0048] The vehicle controller 103, as the brain of the new energy vehicle, is responsible for coordinating and controlling the operation of components such as batteries, motors, motor controllers, and thermal management systems, to achieve intelligent control of the vehicle's power distribution, energy management, and vehicle functions.

[0049] The conventional braking system 104, including the conventional brake system, mainly controls the deceleration and parking process of the vehicle by adjusting the clamping torque.

[0050] The power battery system 105 is mainly used to provide a main power source for the vehicle and to provide power for the motor when driving.

[0051] The motor and motor controller 106, where the motor is the core component that converts electrical energy into mechanical energy and provides power when the vehicle is driving, 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 working state of the motor so that the motor can achieve the functions of acceleration, deceleration and braking. Specifically, the motor controller can change the working state of the motor by adjusting the current and voltage, and decide whether the motor drives the vehicle forward or recovers energy.

[0052] Among them, the motor and the motor controller 106 can also constitute an electric braking system. The electric braking system can be understood as adjusting the reverse torque of the motor through the motor controller to achieve vehicle deceleration or parking. In this process, the vehicle is braked by converting electrical energy into mechanical energy. The principles involved include energy recovery and braking control. Energy recovery can be understood as when the vehicle decelerates or stops, the motor controller controls the motor to generate reverse torque, converts the vehicle's kinetic energy into electrical energy, and stores it back in the battery, thereby extending the cruising range. This control method can reduce dependence on traditional mechanical brakes. Correspondingly, the electric braking process can be understood as the process of braking the vehicle mainly through the electric braking system.

[0053] For new energy vehicles, braking can be performed through a traditional braking system (including a traditional brake system, which mainly controls the deceleration and parking of the vehicle by adjusting the clamping torque). When the traditional braking system fails, in order to ensure driving safety, the electric braking function can be activated to give the motor the maximum recovery torque, thereby achieving parking of the vehicle through the motor. In the embodiment of the present application, the vehicle 100 can determine the initial torque for parking on a slope when the electric braking function of the vehicle is activated, and correct the initial torque for parking on a slope based on the target correction factor corresponding to the rate of change of the vehicle speed when the vehicle is sliding on the current road surface and the number of sliding slopes, and obtain the target torque for parking on a slope. After that, when the preset parking conditions are met, the motor is controlled based on the target torque for parking on a slope until the vehicle completes parking. In this way, during the parking process of the vehicle, the initial hill-holding torque is corrected by the target correction factor corresponding to the actual driving condition of the vehicle (the rate of change of the hill-holding speed and the number of times the vehicle rolls down the slope when rolling down the slope on the current road surface), so that the corrected hill-holding target torque can be more in line with the actual parking demand, that is, the corrected hill-holding target torque has higher accuracy, thereby avoiding the phenomenon of the vehicle rolling due to errors in the initial value of the hill-holding torque and the inability to match the actual parking demand of the vehicle, thereby improving the safety of the vehicle during parking.

[0054] The vehicle parking control method provided in the embodiment of the present application is explained below.

[0055] See also Figure 2 , Figure 21 is a flow chart of a vehicle parking control method provided by an embodiment of the present application. The method can be executed by a vehicle controller, or by a vehicle controller and a motor and a motor controller in collaboration, etc. For ease of explanation, the present application uses a vehicle controller (e.g. Figure 1 The vehicle parking control method is described as an example in which the vehicle controller 103 in the vehicle 100 shown in FIG. Figure 2 As shown, the vehicle parking control method may include but is not limited to the following steps:

[0056] S201 : When the electric braking function of the vehicle is activated, determine an initial hill-holding torque.

[0057] Among them, the electric braking function and the activation conditions of the electric braking function can be pre-configured in the vehicle in the present application. The electric braking function can be understood as a function of controlling vehicle braking based on the above-mentioned electric braking system. When this function is activated, it can replace the traditional braking system to achieve vehicle deceleration and parking. The activation conditions of the electric braking function can include one or more conditions.

[0058] Among them, the motor under the electric braking function is the same motor as the motor during normal driving 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 conditions and return conditions of the electric braking function.

[0059] The hill-holding initial torque may be understood as the motor torque preliminarily determined to enable the vehicle to hold the vehicle on the hill when the electric braking function of the vehicle is activated.

[0060] In an optional embodiment, during the driving of the vehicle, the vehicle controller can obtain 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. After the aforementioned electric braking function is activated, the motor can be controlled by the deceleration torque (or dynamic torque) to achieve deceleration of the vehicle. In addition, an initial torque for holding on a hill can also be determined.

[0061] For example, during the driving process of the vehicle, the vehicle controller can obtain multiple status information of the vehicle in real time, and match the multiple status information with the activation conditions of the electric brake function to determine whether the activation conditions of the electric brake function are met. If the vehicle controller determines that the activation conditions of the electric brake function are met, it can activate the electric brake function, and then control the motor through the deceleration torque to achieve vehicle deceleration, and determine the initial torque for holding the slope.

[0062] Optionally, the vehicle controller can determine the initial torque for holding the hill based on the current speed of the vehicle and the slope of the road on which the vehicle is located, and determine the initial torque for holding the hill by looking up a table, or it can input the current speed of the vehicle and the slope of the road on which the vehicle is located into a pre-built initial torque for holding the hill determination model to obtain the initial torque for holding the hill, etc., which is not limited here. Among them, the above-mentioned table includes the correspondence between multiple speed and slope combinations and multiple initial torques for holding the hill. Optionally, the table can be a table preset in the vehicle controller, or it can be a table preset in a database and readable by the vehicle controller, etc., which is not limited here.

[0063] S202, obtaining the speed change rate and the number of times the vehicle rolls down a slope when the vehicle rolls down a slope on the current road surface.

[0064] Wherein, rolling down a slope refers to the phenomenon that a vehicle slides down a slope. Optionally, the vehicle controller can determine whether the vehicle is rolling down a slope by comparing the vehicle speed change rate with a preset minimum vehicle speed change rate threshold. For example, assuming that the vehicle speed change rate is less than the preset minimum vehicle speed change rate threshold, the vehicle controller can determine that the vehicle is rolling down a slope.

[0065] The speed change rate of the rolling slope vehicle may be information or data that characterizes the speed change of the vehicle during the rolling slope process, and may be positive or negative. For example, the speed change rate of the rolling slope vehicle may be negative when the vehicle is rolling backward (the vehicle is rolling uphill), and positive when the vehicle is rolling forward (the vehicle is rolling downhill). Optionally, the speed change rate of the rolling slope vehicle may be determined by the vehicle controller by calculating the speed of the vehicle at different times when the vehicle is rolling downhill on the current road surface through the wheel speed or the vehicle's drive motor speed, and is determined based on the derivation of the speed, which is not limited here.

[0066] The number of times of rolling down the slope refers to the number of times the vehicle rolls down the slope during the process of decelerating and stopping on the slope. Optionally, the number of times of rolling down the slope can be detected in real time by the vehicle controller when the vehicle enters the current road surface.

[0067] In an optional embodiment, the vehicle controller can detect whether the vehicle is slipping while controlling the vehicle deceleration based on the deceleration torque. If the detection result shows that the vehicle is slipping, the vehicle controller can record the rate of change of the vehicle's slipping speed and the number of times the vehicle slips when it is sliding down the slope on the current road surface.

[0068] S203, obtaining a target correction factor corresponding to the speed change rate of the vehicle rolling down the slope and the number of times the vehicle rolls down the slope, and correcting the initial torque for holding the slope based on the target correction factor to obtain a target torque for holding the slope.

[0069] The target correction factor refers to a correction factor used to correct the initial torque of the hill-holding state.

[0070] Optionally, the vehicle controller obtains the target correction factor corresponding to the rolling hill speed change rate and the number of rolling hills, which can be determined by looking up a table based on the rolling hill speed change rate and the number of rolling hills; or it can be obtained by inputting the rolling hill speed change rate and the number of rolling hills into a pre-built correction factor determination model, which is not limited here. Among them, the above-mentioned table includes the correspondence between multiple combinations of rolling hill speed change rates and rolling hill times and multiple correction factors, the correction factor is positively correlated with the absolute value of the rolling hill speed change rate in the combination, and the correction factor is positively correlated with the number of rolling hills in the combination. Optionally, the table can be a table preset in the vehicle controller, or it can be a table preset in a database and readable by the vehicle controller, etc., which is not limited here.

[0071] Among them, the vehicle controller may roll down the slope multiple times during the process of controlling the vehicle deceleration based on the deceleration torque. In this case, the vehicle controller needs to dynamically determine the target correction factor corresponding to the speed change rate of the rolling slope and the number of rolling slopes obtained each time the vehicle rolls down the slope, and dynamically determine the target torque for holding the slope based on the latest determined target correction factor corresponding to the rolling slope.

[0072] In an optional implementation, the vehicle controller corrects the initial hill-holding torque based on the target correction factor to obtain the hill-holding target torque, which may include: performing product processing on the target correction factor and the initial hill-holding torque to obtain the hill-holding target torque.

[0073] S204: When the preset parking condition is met, control the motor based on the hill-parking target torque until the vehicle is parked.

[0074] Among them, the preset parking condition can be one condition or multiple conditions, and the parking condition can be determined based on the historical parking information of the vehicle. In an optional embodiment, during the driving process of the vehicle, the vehicle controller can obtain multiple status information of the vehicle in real time or periodically, and determine whether the preset parking condition is met based on one or more of the multiple status information. Exemplarily, the preset parking condition is determined based on the vehicle speed. The vehicle controller can determine that the preset parking condition is met when it is determined that the following conditions are met: the current ground speed is less than a preset speed threshold (for example, 5km / h).

[0075] In an optional implementation, the vehicle controller may control the motor controller in the vehicle to adjust the motor output torque to gradually switch to the hill-holding target torque until the vehicle completes parking.

[0076] In the embodiment of the present application, the vehicle controller in the vehicle determines the initial hill-holding torque when the electric braking function of the vehicle is activated; obtains the hill-holding speed change rate and the number of times the vehicle rolls down a slope on the current road surface; obtains the target correction factor corresponding to the hill-holding speed change rate and the number of times the vehicle rolls down a slope, and corrects the initial hill-holding torque based on the target correction factor to obtain the hill-holding target torque; and when the preset parking conditions are met, controls the motor based on the hill-holding target torque until the vehicle completes parking. By adopting this method, the vehicle can correct the initial holding torque based on the target correction factor corresponding to the rolling speed change rate and the number of rolling times when the vehicle rolls down the slope on the current road surface when the electric braking function is activated, so as to obtain the holding target torque, and control the motor based on the holding target torque when the preset parking conditions are met until the vehicle completes parking. In this way, during the parking process of the vehicle, the initial holding torque is corrected based on the target correction factor corresponding to the actual driving situation of the vehicle (the rolling speed change rate and the number of rolling times when the vehicle rolls down the slope on the current road surface), so that the corrected holding target torque can be more in line with the actual parking demand, that is, the corrected holding target torque has higher accuracy, thereby avoiding the phenomenon of the vehicle rolling due to errors in the initial value of the holding torque and the inability to match the actual parking demand of the vehicle, and further improving the safety of the vehicle during parking.

[0077] In an optional embodiment, Figure 2 In the vehicle parking control method shown, the vehicle controller determines the initial torque for holding on a hill when the electric braking function of the vehicle is activated, which may include: when the electric braking function of the vehicle is activated, if the preset slope update condition is met, the slope of the road surface on which the vehicle is currently located is determined based on the vehicle speed change rate, current wheel-end torque, vehicle mass and current ground speed within a preset time period, and the previously determined slope is updated based on the slope; the initial torque for holding on a hill is determined based on the updated slope.

[0078] In some embodiments, the vehicle controller can also obtain the vehicle speed change rate and the current wheel-end torque when the vehicle's electric braking function is activated; differentiate the vehicle speed change rate to obtain the vehicle's speed jerk; and determine that the preset slope update condition is met when the absolute value of the vehicle speed jerk is less than a preset jerk threshold, the duration of the vehicle speed jerk is greater than or equal to the preset duration, the absolute value of the difference between the target wheel-end torque and the current wheel-end torque is less than the preset threshold, the current wheel-end torque is less than the preset torque threshold, and the vehicle's current ground speed is greater than the preset speed threshold.

[0079] The vehicle speed change rate may be information or data that characterizes the change in vehicle speed, and may be positive or negative. For example, the vehicle speed change rate may be negative when the vehicle speed decreases, and positive when the vehicle speed increases. Optionally, the vehicle speed change rate may be determined by the vehicle controller based on data captured by sensors in the vehicle (such as acceleration sensors), or may be determined based on other methods, for example, by calculating the vehicle speed at different times through the wheel speed or the vehicle's drive motor speed to determine the vehicle speed change rate, which is not limited here.

[0080] The current wheel-end torque may be the torque currently detected by the vehicle controller and applied to the vehicle wheels.

[0081] The target wheel-end torque may be the torque required to be applied to the vehicle wheels to keep the vehicle in a stationary state.

[0082] For example, assuming that the preset jerk threshold is 0.1 m / s 3 , the preset duration is 100ms, the preset threshold is 200Nm, the preset torque threshold is -500Nm, the preset vehicle speed threshold is 5km / h, and it is assumed that the absolute value of the vehicle speed jerk determined by the vehicle controller is 0.09m / s 3 , the duration of the vehicle speed jerk is 100ms, the absolute value of the difference between the target wheel end torque and the current wheel end torque is 180Nm, the current wheel end torque is -600Nm, and the current ground speed of the vehicle is 6km / h. In this case, the vehicle controller can determine the absolute value of the vehicle speed jerk to be 0.09m / s 3 Less than the preset jerk threshold of 0.1m / s 3 , the duration of the vehicle speed jerk 100ms is equal to the preset duration 100ms, the absolute value of the difference between the target wheel-end torque and the current wheel-end torque 180Nm is less than the preset threshold 200Nm, the current wheel-end torque -600Nm is less than the preset torque threshold -500Nm, and the vehicle's current ground speed of 6km / h is greater than the preset speed threshold 5km / h. At this time, the vehicle controller can determine that the preset slope update condition is met.

[0083] In some embodiments, the slope of the road surface on which the vehicle is currently located is determined based on the vehicle speed change rate, current wheel-end torque, vehicle mass and current ground speed of the vehicle within a preset time period, including: based on the vehicle speed change rate and current wheel-end torque of the vehicle within the preset time period, looking up a table (recorded as a first correspondence table) to obtain the initial slope of the road surface on which the vehicle is currently located; based on a first correction factor corresponding to the vehicle mass, correcting the initial slope to obtain a corrected slope; based on a second correction factor corresponding to the current ground speed, correcting the corrected slope to obtain the slope of the road surface on which the vehicle is currently located.

[0084] The first correspondence table may include a combination of multiple vehicle speed change rates and wheel end torques, and correspondences between multiple initial slopes. Optionally, the first correspondence may be a table preset in the vehicle controller, or a table preset in a database and readable by the vehicle controller, etc., which is not limited here. Exemplarily, the first correspondence table may be shown in Table 1 below.

[0085] Table 1

[0086]

[0087] Among them, a positive slope indicates an uphill slope, and a negative slope indicates a downhill slope. It can be seen from Table 1 that when the vehicle's ground speed decelerates from a positive value to 0 (i.e., the speed change rate is a negative value), if the speed change rate remains unchanged, the greater the absolute value of the wheel-end torque, the greater the absolute value of the determined initial slope; when the vehicle's ground speed transitions from a negative value to 0 (i.e., the speed change rate is a positive value), if the speed change rate remains unchanged, the greater the absolute value of the wheel-end torque, the smaller the absolute value of the determined initial slope. In this way, by looking up the table, the initial slope of the road surface on which the vehicle is currently located can be determined simply and efficiently.

[0088] Optionally, the vehicle controller corrects the initial slope based on the first correction factor corresponding to the vehicle mass to obtain the corrected slope, which may include: obtaining the vehicle mass, looking up a table (recorded as the second corresponding relationship table) based on the vehicle mass to obtain the first correction factor corresponding to the vehicle mass; and taking the product of the first correction factor and the initial slope as the corrected slope. In this way, the phenomenon that the speed change rate is different due to the difference in vehicle mass, thereby causing the slope of the road where the vehicle is currently located to have an error can be avoided, thereby improving the accuracy of the slope of the road where the vehicle is currently located.

[0089] Among them, the second correspondence table includes correspondences between multiple vehicle masses and multiple correction factors, and the vehicle mass and the correction factor are negatively correlated. Optionally, the second correspondence can be a table preset in the vehicle controller, or a table preset in a database and readable by the vehicle controller, etc., which is not limited here. Exemplarily, the second correspondence table can be shown in Table 2 below.

[0090] Table 2

[0091]

[0092] In Table 2, the unloaded mass refers to the mass of the vehicle when it is empty; the fully loaded mass refers to the mass of the vehicle when it is fully loaded. As can be seen from Table 2, the greater the mass of the vehicle, the greater the torque required for braking, and therefore the smaller the first correction factor. By looking up the table, the first correction factor for correcting the initial slope can be determined simply and efficiently.

[0093] Optionally, the vehicle controller corrects the slope based on the second correction factor corresponding to the current vehicle speed to obtain the slope of the road surface the vehicle is currently on, which may include: looking up a table (recorded as the third corresponding relationship table) based on the current vehicle speed to obtain the second correction factor corresponding to the current vehicle speed to the ground; and taking the product of the second correction factor and the corrected slope as the slope of the road surface the vehicle is currently on. In this way, it is possible to avoid the situation where the speed change rate is different due to the difference in vehicle speed, thereby causing errors in determining the slope of the road surface the vehicle is currently on, thereby improving the accuracy of the slope of the road surface the vehicle is currently on.

[0094] Among them, the third correspondence table includes correspondences between multiple vehicle speeds and multiple correction factors, and the vehicle speed and the correction factor are negatively correlated. Optionally, the third correspondence can be a table preset in the vehicle controller, or a table preset in a database and readable by the vehicle controller, etc., which is not limited here. Exemplarily, the third correspondence table can be shown in Table 3 below.

[0095] Table 3

[0096]

[0097] It can be seen from Table 3 that the greater the ground speed, the smaller the correction factor. By looking up the table, the second correction factor for correcting the corrected slope can be determined simply and efficiently.

[0098] In some embodiments, the current vehicle speed relative to the ground is determined by: obtaining the vehicle's current motor speed, tire radius, speed ratio, and the conversion coefficient between motor speed and vehicle speed; determining the vehicle's speed based on the current motor speed, tire radius, speed ratio, and conversion coefficient; determining the current vehicle speed relative to the ground based on the vehicle speed and the vehicle's direction of travel.

[0099] Optionally, the vehicle controller may use the following formula (1) to determine the vehicle speed based on the current motor speed, tire radius, speed ratio, and conversion coefficient.

[0100] (1)

[0101] In formula (1), V represents the vehicle speed (unit: km / h); n represents the motor speed; r represents the tire radius (unit: meter); i represents the speed ratio; and μ is the conversion coefficient from speed to vehicle speed.

[0102] With this implementation, when the electric braking function of the vehicle is activated, if the preset slope update condition is met, the vehicle controller determines the slope of the road surface on which the vehicle is currently located based on the vehicle speed change rate, the current wheel-end torque, the vehicle mass and the current ground speed within a preset time period, and updates the previously determined slope based on the slope; the initial hill-holding torque is determined based on the updated slope, thereby avoiding the situation where the slope is determined with errors due to differences in the vehicle mass and the current ground speed, and improving the accuracy of the slope of the road surface on which the vehicle is currently located. Therefore, in the process of updating the previously determined slope based on the slope with high accuracy determined in real time and determining the initial hill-holding torque based on the updated slope (i.e. the slope with high accuracy determined in real time), the accuracy of the determined initial hill-holding torque can be improved.

[0103] In an optional embodiment, Figure 2 In the vehicle parking control method, the vehicle controller obtains the target correction factor corresponding to the rolling hill speed change rate and the number of rolling hill times, which may include: determining the target correction factor corresponding to the rolling hill speed change rate and the number of rolling hill times based on a preset corresponding relationship; the preset corresponding relationship includes a corresponding relationship between a combination of multiple rolling hill speed change rates and the number of rolling hill times and multiple correction factors; the correction factor is positively correlated with the rolling hill speed change rate in the combination, and the correction factor is positively correlated with the number of rolling hill times in the combination.

[0104] Optionally, the preset correspondence may be a table preset in the vehicle controller (recorded as the fourth correspondence table), or a table preset in a database and readable by the vehicle controller (recorded as the fourth correspondence table), etc., which is not limited here. Among them, the fourth correspondence table includes the correspondence between a plurality of combinations of the rolling speed change rate and the number of rolling times and a plurality of correction factors; the correction factor is positively correlated with the absolute value of the rolling speed change rate in the combination, and the correction factor is positively correlated with the number of rolling times in the combination. Exemplarily, the fourth correspondence table may be shown in Table 4 below.

[0105] Table 4

[0106]

[0107] When the absolute value of the speed change rate of the rolling vehicle is larger, it proves that the rolling vehicle is rolling faster, and the more times the rolling vehicle rolls, it proves that the rolling torque is not accurate enough. Therefore, it can be seen from Table 2 that the larger the absolute value of the speed change rate of the rolling vehicle is, the larger the number of rolling vehicles is, and the larger the target correction factor is. For example, the speed change rate of the rolling vehicle is 0m / s 2 , when the number of sliding slopes is 0, the target correction factor is 1; and the speed change rate of the sliding slope is 2m / s 2 , when the number of slope slips is 1, the target correction factor is 2.

[0108] With this implementation, the vehicle controller determines the target correction factor corresponding to the rolling speed change rate and the rolling number based on a preset corresponding relationship, wherein the preset corresponding relationship includes the corresponding relationship between a plurality of combinations of rolling speed change rates and rolling numbers and a plurality of correction factors; the correction factor is positively correlated with the absolute value of the rolling speed change rate in the combination, and the correction factor is positively correlated with the rolling number in the combination. In this way, the efficiency of determining the target correction factor for correcting the initial torque for parking can be improved, thereby facilitating the efficiency of determining the target torque for parking, and further facilitating the rapid parking of the vehicle.

[0109] In an optional embodiment, Figure 2 In the vehicle parking control method shown, the vehicle controller may also activate the electric braking function when at least one of the following conditions is met:

[0110] (1) A first condition that the duration of pressing a target control of the vehicle is greater than a preset duration threshold;

[0111] (2) A second condition that the number of key presses on the target control within a preset time period is greater than a preset key press threshold;

[0112] (3) A third condition that 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.

[0113] The target control may be a physical button or a virtual button inside the vehicle, and the association between the target button and the electric brake function is predefined. The target button may be a dedicated button for activating or deactivating the electric brake function, or may be a button that realizes other functions and is configured to activate or deactivate the electric brake function under specific operating conditions.

[0114] That is to say, the vehicle controller can activate the electric braking function when at least one of the first condition, the second condition, and the third condition is met.

[0115] For example, assuming that the preset duration threshold corresponding to the target control is 1s, and the driver presses the target control for 2s, the vehicle controller can determine that the pressing duration of 2s for the target control exceeds the preset duration threshold of 1s. In this case, it can be determined that there is an intention to decelerate. At this time, the vehicle controller can activate the electric braking function.

[0116] For another example, assuming that the duration of the preset time period is 1s, the preset key count threshold for the target control within 1s is 2 times, and the driver presses the target control 3 times within 1s, the vehicle controller can determine that the number of key presses for the target control 3 times within 1s is greater than the preset key count threshold of 2 times. In this case, it can be determined that there is an intention to decelerate, and the vehicle controller can activate the electric braking function.

[0117] For another example, assuming that the preset relative distance threshold is 20m, the preset relative speed threshold is 50km / h, and assuming that 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 less than the preset relative distance threshold of 20m, and the relative speed of 55km / h is greater than the preset relative speed threshold of 50km / h. In this case, it can be determined that there is a risk of collision. At this time, the vehicle controller can activate the electric braking function.

[0118] Optionally, the vehicle controller may also exit the electric braking function when it determines that at least one of the following conditions is met: (1) the accelerator pedal opening is greater than a preset proportional value; (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 the preset distance threshold.

[0119] For example, assuming that the accelerator opening is 30% and the preset ratio value is 20%, the vehicle controller can determine that the accelerator opening of 30% is greater than the preset ratio value of 20%. In this case, it can be determined that there is an acceleration intention. At this time, the vehicle controller can exit the electric braking function.

[0120] For another example, assuming that the preset relative distance threshold is 30m, the preset relative speed threshold is 20km / h, and assuming that 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 31m between the vehicle and the vehicle in front is greater than the preset relative distance threshold 30m, and the relative speed 8km / h is less than the preset relative speed threshold 10km / h. In this case, it can be determined that there is no collision risk. At this time, the vehicle controller can exit the electric braking function.

[0121] By adopting this implementation mode, the vehicle controller can determine under what circumstances to activate the electric braking function, so that when the triggering conditions for activating the electric braking function are detected, the electric braking function can be activated in time, which is conducive to timely control of vehicle braking.

[0122] Combine the following Figure 3 , the overall process of the vehicle parking control method provided by the embodiment of the present application is described. Figure 3 , Figure 3 FIG. 1 is a flow chart of another vehicle parking control method provided by an embodiment of the present application, which can be executed by a vehicle controller. Figure 3 As shown, the vehicle parking control method may include but is not limited to the following steps.

[0123] S301, monitor the motor speed, button status, vehicle mass, throttle opening and wheel-end torque of the vehicle in real time.

[0124] S302: Calculate the current vehicle speed based on the motor speed.

[0125] In an optional implementation, when the vehicle controller calculates the vehicle speed based on the motor speed, the aforementioned formula (1) may be used, which will not be described in detail here.

[0126] Based on the vehicle speed and the current driving direction of the vehicle, the ground speed can be obtained. The driving direction can be forward or reverse; the forward direction is the direction the front of the vehicle is facing. In some possible embodiments, the driving direction of the vehicle can be determined by the positive and negative of the motor speed, that is, forward and reverse. For example, a positive motor speed can correspond to a forward driving direction, and a negative motor speed can correspond to a reverse driving direction. For example, V Direction Indicates the vehicle's driving direction. When the motor speed is less than -50rpm, the driving direction is reverse, then V Direction Equal to -1, when the motor speed is greater than 50rpm, the driving direction is forward, V Direction Equal to 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.

[0127] S303: Determine the activation flag of the electric brake function based on the button status, throttle opening, relative distance, and relative speed.

[0128] Exemplarily, the vehicle controller may also activate the electric braking function when at least one of the following conditions is met: (1) the duration of pressing 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 number of key presses threshold of 2; (3) the relative distance between the vehicle and the vehicle in front is less than a preset relative distance threshold of 1 meter and the relative speed is greater than a preset relative speed threshold of 20 meters per second.

[0129] For example, the vehicle controller may also exit the electric braking function when 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 3m and the relative speed is less than a preset relative speed threshold of 10m / s.

[0130] S304: Determine the slope of the road on which the vehicle is located based on the vehicle speed change rate, the current wheel end torque, the vehicle mass and the current ground speed.

[0131] The basic principle is as follows: the vehicle controller uses the vehicle speed change rate as the horizontal coordinate and the current wheel-end torque as the vertical coordinate to look up the table (such as Table 1 above) to calculate the initial slope, obtains the actual road slope through the test equipment, and calibrates the look-up table slope to match the actual slope. The matching method is to prioritize the vehicle speed change rate generated by the current wheel-end torque on a flat road. When the actual vehicle speed change rate is not equal to the vehicle speed change rate on a flat road, it proves that the current road has a slope.

[0132] In order to avoid different speed change rates due to differences in vehicle mass, the vehicle mass is selected to correct the slope. Optionally, the vehicle controller can determine the first correction factor for correcting the initial slope based on the vehicle mass table (such as Table 2 above), and use the product between the first correction factor and the initial slope as the corrected slope. Furthermore, in order to avoid different speed change rates due to differences in vehicle speed, the vehicle speed is selected to correct the corrected slope again. Optionally, the vehicle controller can determine the second correction factor for correcting the corrected slope based on the current ground speed table (such as Table 3 above), and use the product between the second correction factor and the corrected slope as the slope of the road surface on which the vehicle is currently located.

[0133] The vehicle controller may use the product of the initial slope, the first correction factor and the second correction factor as the slope of the road on which the vehicle is currently located.

[0134] S305: Establish a slope update mechanism based on the vehicle speed change rate, the target wheel end torque, the current wheel end torque, and the current vehicle speed relative to the ground.

[0135] Optionally, if the following conditions are met, it means that the vehicle has entered the steady state stage, and the slope value calculated by table lookup is more accurate. The conditions for allowing slope update are as follows:

[0136] ① Calculate the vehicle speed jerk based on the derivative of the vehicle speed change rate. When its absolute value is less than the set threshold of 0.1m / s 3 If the state is maintained for 100ms, it means that the vehicle has entered the steady state stage.

[0137] ② If the absolute value of the difference between the target wheel-end torque and the current wheel-end torque is less than the set threshold of 200Nm, it means that the current vehicle has entered the steady-state stage;

[0138] ③ If the actual wheel-end torque is less than the set threshold value -500Nm, it means that the current vehicle has a certain deceleration;

[0139] ④ The current vehicle speed relative to the ground is greater than the set threshold of 5 km / h to avoid the low-speed electric braking target torque decaying to the required hill-holding torque, resulting in inaccurate slope calculation;

[0140] If the above four conditions are met, it can be determined that the slope update conditions are met. Considering that the slope will not change rapidly, the rising edge triggers the filtering process after the first slope update, that is, when the slope value of the current cycle is not equal to 0, to avoid its sudden change affecting the control effect.

[0141] To avoid incorrect use of slope, this scenario only ensures that the vehicle's speed is controllable on the slope. The vehicle must eventually be parked on a flat road. That is, when this function is exited, the slope must be reset to zero to ensure that the vehicle can safely stop on a flat road.

[0142] S306: Determine the deceleration torque and the initial torque for holding the slope based on the electric brake function flag, the slope, the current vehicle speed relative to the ground, and the maximum recovery torque available from the motor.

[0143] Among them, deceleration torque refers to the torque under vehicle dynamics. The main goal of deceleration torque is deceleration, which can be dynamically adjusted according to deceleration requirements. Deceleration torque can occur at various speeds of the vehicle and is not limited to use when stopping.

[0144] Optionally, the deceleration torque may be determined by the vehicle controller based on the maximum regenerative torque available from the motor.

[0145] Optionally, the initial torque for holding the hill can be determined by a vehicle controller based on the slope and the current vehicle speed relative to the ground by looking up the table, or it can be obtained by inputting the slope and the current vehicle speed relative to the ground into a pre-built initial torque for holding the hill determination model, which is not limited here.

[0146] S307, introducing a self-learning mechanism to correct the initial torque for holding the slope and obtain the target torque for holding the slope.

[0147] Considering that the required torque for holding a hill under different loads is inconsistent, a self-learning mechanism is set up to prevent the vehicle from sliding down the hill due to too small holding torque. Taking D gear as an example, the self-learning mechanism is allowed to operate if the following conditions are met:

[0148] ① When the vehicle is on an uphill slope and slides backward, it means that the parking torque is too small;

[0149] ② When the vehicle is on a downhill slope and slides forward, it means that the parking torque is too small.

[0150] When the self-learning mechanism is running, self-learning is performed based on the vehicle's performance when rolling on a slope, and the initial value of the on-slope torque is corrected based on the vehicle speed change rate and the number of times the vehicle rolls down the slope to obtain the on-slope target torque. The larger the absolute value of the vehicle speed change rate, the faster the vehicle rolls down the slope, and the more times the vehicle rolls down the slope, the more accurate the on-slope torque is. Optionally, the vehicle controller can use the vehicle speed change rate as the horizontal coordinate and the number of times the vehicle rolls down the slope as the vertical coordinate to look up a table (such as Table 4 above) to determine the target correction factor for correcting the initial on-slope torque, and use the product of the target correction factor and the initial on-slope torque as the on-slope target torque.

[0151] S308: When the preset parking condition is met, control the motor based on the hill-parking target torque until the vehicle is parked.

[0152] In an embodiment of the present application, 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 slope of the road on which the vehicle is located based on the vehicle speed change rate, the current wheel-end torque, the vehicle mass and the current ground speed; establish a slope update mechanism based on the vehicle speed change rate, the target wheel-end torque, the current wheel-end torque, and the current ground speed; when it is determined that the electric braking function flag is activated, determine the deceleration torque and the initial torque for holding the hill based on the slope, the current ground speed, and the maximum recovery torque available from the motor, and introduce a self-learning mechanism to correct the initial torque for holding the hill to obtain the target torque for holding the hill; finally, when the preset parking conditions are met, control the motor based on the target torque for holding the hill until the vehicle completes parking. In this way, by updating the slope in real time during the vehicle parking process, a more accurate slope can be obtained, and thus, a more accurate parking initial torque can be determined based on the more accurate slope. Afterwards, by introducing a self-learning mechanism to correct the more accurate parking initial torque, a more accurate hill-parking target torque can be obtained. Furthermore, when the preset parking conditions are met, the motor is controlled based on the hill-parking target torque until the vehicle completes parking, which can improve the safety of the vehicle's electric braking process.

[0153] It should be understood that, although the various steps in the flowcharts involved in the above-mentioned embodiments are displayed in sequence according to the indication of the arrows, these steps are not necessarily executed in sequence according to the order indicated by the arrows. Unless there is a clear explanation in this article, the execution of these steps does not have a strict order restriction, and these steps can be executed in other orders. Moreover, at least a part of the steps in the flowcharts involved in the above-mentioned embodiments can include multiple steps or multiple stages, and these steps or stages are not necessarily executed at the same time, but can be executed at different times, and the execution order of these steps or stages is not necessarily to be carried out in sequence, but can be executed in turn or alternately with other steps or at least a part of the steps or stages in other steps.

[0154] Based on the same inventive concept, the embodiment of the present application also provides a vehicle parking control device for implementing the vehicle parking control method involved above. The implementation scheme for solving the problem provided by the device is similar to the implementation scheme recorded in the above method, so the specific limitations of one or more vehicle parking control device embodiments provided below can refer to the limitations of the vehicle parking control method above, and will not be repeated here.

[0155] See also Figure 4 , Figure 4Schematic diagram of the structure of a vehicle parking control device provided in an embodiment of the present application. Figure 4 As shown, the vehicle parking control device may include but is not limited to:

[0156] A determination module 401 is used to determine an initial hill-holding torque when the electric braking function of the vehicle is activated;

[0157] The acquisition module 402 is used to acquire the speed change rate and the number of times the vehicle rolls down the slope when the vehicle rolls down the slope on the current road surface;

[0158] The acquisition and correction module 403 is used to acquire the target correction factor corresponding to the speed change rate of the vehicle rolling down the slope and the number of rolling down the slope, and correct the initial torque for holding the slope based on the target correction factor to obtain the target torque for holding the slope;

[0159] The torque control module 404 is used to control the motor based on the hill-parking target torque until the vehicle is parked when the preset parking condition is met.

[0160] In one embodiment, the determination module 401 is used to determine the initial torque for holding a hill when the electric braking function of the vehicle is activated. Specifically, it is used to: when the electric braking function of the vehicle is activated, if a preset slope update condition is met, determine the slope of the road surface on which the vehicle is currently located based on the vehicle speed change rate, current wheel-end torque, vehicle mass and current ground speed within a preset time period, and update the previously determined slope based on the slope; determine the initial torque for holding a hill based on the updated slope.

[0161] In one embodiment, the acquisition and correction module 403 is also used to: acquire the vehicle speed change rate and the current wheel-end torque when the vehicle's electric braking function is activated; differentiate the vehicle speed change rate to obtain the vehicle's speed jerk; and determine that the preset slope update condition is met when the absolute value of the vehicle speed jerk is less than a preset jerk threshold, the duration of the vehicle speed jerk is greater than or equal to the preset duration, the absolute value of the difference between the target wheel-end torque and the current wheel-end torque is less than the preset threshold, the current wheel-end torque is less than the preset torque threshold, and the vehicle's current ground speed is greater than the preset speed threshold.

[0162] In one embodiment, when the determination module 401 is used to determine the slope of the road surface on which the vehicle is currently located based on the vehicle speed change rate, the current wheel-end torque, the vehicle mass and the current ground speed within a preset time period, it is specifically used to: based on the vehicle speed change rate and the current wheel-end torque within the preset time period, look up the table to obtain the initial slope of the road surface on which the vehicle is currently located; based on the first correction factor corresponding to the vehicle mass, correct the initial slope to obtain the corrected slope; based on the second correction factor corresponding to the current ground speed, correct the corrected slope to obtain the slope of the road surface on which the vehicle is currently located.

[0163] In one embodiment, the acquisition module 402 is also used to acquire the vehicle's current motor speed, tire radius, speed ratio and the conversion coefficient between the motor speed and the vehicle speed; the determination module 401 is also used to determine the vehicle speed based on the current motor speed, tire radius, speed ratio and the conversion coefficient; and determine the current vehicle speed relative to the ground based on the vehicle speed and the vehicle's driving direction.

[0164] In one embodiment, when the acquisition and correction module 403 is used to obtain the target correction factor corresponding to the speed change rate of the vehicle rolling down a slope and the number of times the vehicle rolls down a slope, it is specifically used to: determine the target correction factor corresponding to the speed change rate of the vehicle rolling down a slope and the number of times the vehicle rolls down a slope based on a first corresponding relationship; the first corresponding relationship includes a corresponding relationship between a combination of multiple speed change rates of the vehicle rolling down a slope and the number of times the vehicle rolls down a slope and multiple correction factors; the correction factor is positively correlated with the speed change rate of the vehicle rolling down a slope in the combination, and the correction factor is positively correlated with the number of times the vehicle rolls down a slope in the combination.

[0165] In one embodiment, the device may also 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 that the key pressing duration for the target control of the vehicle is greater than a preset duration threshold; a second condition that the number of key pressings for the target control within a preset time period is greater than a preset number threshold; a third condition that 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.

[0166] Each module in the above-mentioned vehicle parking control device can be implemented in whole or in part by software, hardware or a combination thereof. Each module can be embedded in or independent of a processor in a computer device in the form of hardware, or can be stored in a memory in a vehicle control device in the form of software, so that the processor can call and execute operations corresponding to each module.

[0167] In an exemplary embodiment, a new energy vehicle is provided, and its internal structure diagram can be as follows: Figure 5As shown. The new energy vehicle includes a processor, a memory, an input / output interface, a communication interface, a display unit and an input device. Among them, the processor, the memory and the input / output interface are connected through a system bus, and the communication interface, the display unit and the input device are connected to the system bus through the input / output interface. Among them, the processor of the new energy vehicle is used to provide computing and control capabilities. The memory of the new energy vehicle includes a non-volatile storage medium and an internal memory. The non-volatile storage medium stores an operating system and a computer program. The internal memory provides an environment for the operation of the operating system and the computer program in the non-volatile storage medium. The input / output interface of the new energy vehicle is used to exchange information between the processor and the external device. The communication interface of the new energy vehicle is used to communicate with an external terminal in a wired or wireless manner, and the wireless manner can be realized through WIFI, a mobile cellular network, NFC (near field communication) or other technologies. When the computer program is executed by the processor, a vehicle parking control method is realized. The display unit of the new energy vehicle is used to form a visually visible picture, which can be a display screen, a projection device or a virtual reality imaging device. The display screen can be a liquid crystal display screen or an electronic ink display screen, and the input device of the new energy vehicle can be a touch layer covered on the display screen, or it can be a button, trackball or touchpad set in the new energy vehicle.

[0168] Those skilled in the art will understand that Figure 5 The structure shown in the figure is only a block diagram of a part of the structure related to the scheme of the present application, and does not constitute a limitation on the new energy vehicle to which the scheme of 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 a different arrangement of components.

[0169] In an exemplary embodiment, the present 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, the steps in the above-mentioned vehicle parking control methods are implemented.

[0170] In an exemplary embodiment, the present application provides a computer-readable storage medium on which a computer program is stored. When the computer program is executed by a processor, the steps in the above-mentioned vehicle parking control methods are implemented.

[0171] In an exemplary embodiment, the present application provides a computer program product, including a computer program. When the computer program is executed by a processor, the steps in the above-mentioned vehicle parking control methods are implemented.

[0172] It should be noted that the data involved in this application (including but not limited to the initial torque for holding the hill, the rate of change of vehicle speed for rolling down the hill, the number of rolling down the hills, the target correction factor, the target torque for holding the hill, 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.

[0173] A person of ordinary skill in the art can understand that all or part of the processes in the above-mentioned embodiment method can be completed by instructing the relevant hardware through a computer program, and the computer program can be stored in a non-volatile computer-readable storage medium. When the computer program is executed, it can include the processes of the embodiments of the above-mentioned methods. Among them, any reference to the memory, database or other medium used in the embodiments provided in the present 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. As an illustration and not limitation, RAM can be in various forms, such as static random access memory (SRAM) or dynamic random access memory (DRAM). The database involved in each embodiment provided in this application may include at least one of a relational database and a non-relational database. Non-relational databases may include distributed databases based on blockchains, etc., but are not limited to this. The processor involved in each embodiment provided in this application may be a general-purpose processor, a central processing unit, a graphics processor, a digital signal processor, a programmable logic device, a data processing logic device based on quantum computing, an artificial intelligence (AI) processor, etc., but are not limited to this.

[0174] The technical features of the above embodiments may be combined arbitrarily. To make the description concise, 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.

[0175] The above-described embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the present application. It should be pointed out that, for a person of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the present application shall be subject to the attached claims.

Claims

1. A vehicle parking control method, characterized in that: The method comprises: Determining the initial holding torque when the electric braking function of the vehicle is activated; Obtaining the speed change rate and number of times the vehicle rolls down a slope when rolling down a slope on the current road surface; Obtaining a target correction factor corresponding to the speed change rate of the vehicle rolling down the slope and the number of times the vehicle rolls down the slope, and correcting the initial torque for holding the slope based on the target correction factor to obtain a target torque for holding the slope; When a preset parking condition is satisfied, the motor is controlled based on the hill-parking target torque until the vehicle is parked.

2. The method according to claim 1, characterized in that With the vehicle's electric brake function activated, determine the initial holding torque, including: When the electric brake function of the vehicle is activated, if the preset slope update condition is met, the slope of the road surface on which the vehicle is currently located is determined based on the vehicle speed change rate, the current wheel end torque, the vehicle mass and the current ground speed of the vehicle within a preset time period, and the previously determined slope is updated based on the slope; Based on the updated slope, the hill holding initial torque is determined.

3. The method according to claim 2, characterized in that The method further comprises: When the electric braking function of the vehicle is activated, obtaining the vehicle speed change rate and the current wheel end torque; Deriving the vehicle speed change rate to obtain the vehicle speed jerk of the vehicle; When the absolute value of the vehicle speed jerk is less than the preset jerk threshold, the duration of the vehicle speed jerk is greater than or equal to the preset duration, the absolute value of the difference between the target wheel-end torque and the current wheel-end torque is less than the preset threshold, the current wheel-end torque is less than the preset torque threshold, and the current ground speed of the vehicle is greater than the preset vehicle speed threshold, it is determined that the preset slope update condition is met.

4. The method according to claim 2, characterized in that: The determining the slope of the road surface on which the vehicle is currently located based on the vehicle speed change rate, the current wheel end torque, the vehicle mass and the current ground speed of the vehicle within a preset time period includes: Based on the vehicle speed change rate and the current wheel end torque of the vehicle within a preset time period, looking up a table to obtain the initial slope of the road surface on which the vehicle is currently located; Based on a first correction factor corresponding to the vehicle mass, the initial slope is corrected to obtain a corrected slope; The corrected slope is corrected based on a second correction factor corresponding to the current vehicle speed over the ground to obtain the slope of the road surface on which the vehicle is currently located.

5. The method according to claim 2, characterized in that: The current ground speed is determined by: Obtaining the current motor speed, tire radius, speed ratio, and conversion coefficient between the motor speed and vehicle speed of the vehicle; Determining the speed of the vehicle based on the current motor speed, the tire radius, the speed ratio and the conversion coefficient; The current vehicle speed relative to the ground is determined based on the vehicle speed and the driving direction of the vehicle.

6. The method according to claim 1, characterized in that The step of obtaining the target correction factor corresponding to the speed change rate of the vehicle rolling down the slope and the number of times the vehicle rolls down the slope comprises: Based on a preset corresponding relationship, target correction factors corresponding to the speed change rate of the vehicle rolling down the slope and the number of times the vehicle rolls down the slope are determined; the preset corresponding relationship includes a corresponding relationship between a plurality of combinations of the speed change rate of the vehicle rolling down the slope and the number of times the vehicle rolls down the slope and a plurality of correction factors; the correction factor is positively correlated with the speed change rate of the vehicle rolling down the slope in the combination, and the correction factor is positively correlated with the number of times the vehicle rolls down the slope in the combination.

7. The method according to any one of claims 1 to 6, characterized in that: Also includes: The electric braking function is activated when at least one of the following conditions is met: A first condition that the duration of pressing a key of a target control of the vehicle is greater than a preset duration threshold; A second condition that the number of key presses on the target control within a preset time period is greater than a preset number threshold; The third condition is that 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.

8. A vehicle parking control device, characterized in that: The device comprises: A determination module, used to determine a hill-holding initial torque when an electric brake function of the vehicle is activated; An acquisition module, used for acquiring a speed change rate and a number of times of the vehicle sliding down a slope when the vehicle slides down a slope on a current road surface; An acquisition and correction module, used for acquiring a target correction factor corresponding to the speed change rate of the rolling hill vehicle and the number of rolling hill times, and correcting the hill-holding initial torque based on the target correction factor to obtain a hill-holding target torque; The torque control module is used to control the motor based on the hill-parking target torque when a preset parking condition is met until the vehicle completes parking.

9. A new energy vehicle, comprising a memory and a processor, wherein the memory stores a computer program, characterized in that: When the processor executes the computer program, the steps of the method according to any one of claims 1 to 7 are implemented.

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

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