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

Abstract

The application 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: determining a hill-hold initial torque under the condition that the electric braking function of the vehicle is activated; acquiring a hill-slip speed change rate and a hill-slip frequency of the vehicle when the vehicle is hill-slip on a current road surface; acquiring a target correction factor corresponding to the hill-slip speed change rate and the hill-slip frequency, correcting the hill-hold initial torque based on the target correction factor, and obtaining a hill-hold target torque; and controlling the motor based on the hill-hold target torque until the vehicle completes parking under the condition that a preset parking condition is met. The method can improve the safety of the vehicle parking process.

Description

TECHNICAL FIELD

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

[0002] New energy vehicle technology is increasingly updated, and it is necessary to improve the safety of new energy vehicles, especially the safety of the parking process of the vehicle. To realize vehicle hill holding, the electronic stability control (ESC) module of the vehicle is usually used to control the motor to realize hill holding. However, in the process of controlling the motor to realize hill holding, if the hill holding torque is not accurate enough, the vehicle may slide, thereby reducing the safety of the vehicle parking process.

[0003] Therefore, how to improve the safety of the vehicle parking process has become a problem to be solved. SUMMARY

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

[0005] In a first aspect, the embodiments of the present application provide a vehicle parking control method, which comprises:

[0006] In the case that the electric braking function of the vehicle is activated, the hill holding initial torque is determined;

[0007] The hill rolling speed change rate and the hill rolling frequency of the vehicle when rolling down the slope on the current road surface are obtained;

[0008] The target correction factor corresponding to the hill rolling speed change rate and the hill rolling frequency is obtained, and the hill holding initial torque is corrected based on the target correction factor to obtain the hill holding target torque;

[0009] In the case that the preset parking condition is met, the motor is controlled based on the hill holding target torque until the vehicle completes parking.

[0010] In one of the embodiments, in the case that the electric braking function of the vehicle is activated, the hill holding initial torque is determined, which comprises: in the case that the electric braking function of the vehicle is activated, if the preset slope updating condition is met, the slope of the current road surface of the vehicle is determined based on the speed change rate of the vehicle in the preset time period, the current wheel end torque, the total vehicle mass and the current ground speed, and the previously determined slope is updated based on the slope; the hill holding initial torque is determined based on the updated slope.

[0011] In one of the embodiments, the method further comprises: obtaining the vehicle speed change rate and the current wheel end torque in a case where the electric braking function of the vehicle is activated; obtaining the vehicle speed jerk by differentiating the vehicle speed change rate; determining that the preset slope updating condition is satisfied in a case where 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 a preset duration, the absolute value of the difference between the target wheel end torque and the current wheel end torque is less than a preset threshold, the current wheel end torque is less than a preset torque threshold, and the current vehicle speed on the ground is greater than a preset vehicle speed threshold.

[0012] In one of the embodiments, the slope of the road currently located by the vehicle is determined based on the vehicle speed change rate of the vehicle in a preset time period, the current wheel end torque, the total vehicle mass, and the current vehicle speed on the ground, comprising: obtaining the initial slope of the road currently located by the vehicle based on the vehicle speed change rate of the vehicle in a preset time period and the current wheel end torque; correcting the initial slope based on a first correction factor corresponding to the total vehicle mass to obtain a corrected slope; correcting the corrected slope based on a second correction factor corresponding to the current vehicle speed on the ground to obtain the slope of the road currently located by the vehicle.

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

[0014] In one of the embodiments, the target correction factor corresponding to the hill-start speed change rate and the hill-start frequency is obtained by: determining the target correction factor corresponding to the hill-start speed change rate and the hill-start frequency based on a preset corresponding relationship; the preset corresponding relationship includes a corresponding relationship between a plurality of combinations of hill-start speed change rates and hill-start frequencies and a plurality of correction factors; the correction factor is positively correlated with the hill-start speed change rate in the combination, and the correction factor is positively correlated with the hill-start frequency in the combination.

[0015] In one of the embodiments, the method further comprises: activating the electric braking function in a case where at least one of the following conditions is met: a first condition that the key pressing duration of 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 in a preset time period is greater than a preset number threshold; and 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.

[0016] In a second aspect, the embodiments of the present application provide a vehicle parking control device, which comprises:

[0017] The determining module is configured to determine the initial hill-start torque in a case where the electric braking function of the vehicle is activated.

[0018] The acquisition module is configured to acquire a hill-start speed variation rate and a hill-start frequency of the vehicle when the vehicle is rolling down a slope on a current road surface;

[0019] The acquisition and correction module is configured to acquire a target correction factor corresponding to the hill-start speed variation rate and the hill-start frequency, and correct the hill-start initial torque based on the target correction factor to obtain a hill-start target torque.

[0020] The torque control module is configured to control the motor based on the hill-start target torque until the vehicle completes the hill-start, when a preset hill-start condition is met.

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

[0022] In a fourth aspect, the present application further provides a computer readable storage medium, which stores a computer program, and the computer program implements the steps of the method in the first aspect when executed by a processor.

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

[0024] The vehicle parking control method, device, new energy vehicle and storage medium provided in the above method can determine a hill-hold initial torque when the electric braking function of the new energy vehicle (hereinafter referred to as a vehicle) is activated; obtain a hill-slope speed change rate and a hill-slope frequency when the vehicle is rolling on the current road surface; obtain a target correction factor corresponding to the hill-slope speed change rate and the hill-slope frequency, correct the hill-hold initial torque based on the target correction factor to obtain a hill-hold target torque; and control the motor based on the hill-hold target torque until the vehicle completes parking when a preset parking condition is met. By using the method, the hill-hold initial torque can be corrected based on the target correction factor corresponding to the hill-slope speed change rate and the hill-slope frequency when the vehicle is rolling on the current road surface, the hill-hold target torque is obtained, and the motor is controlled based on the hill-hold target torque until the vehicle completes parking when the preset parking condition is met. In this way, the hill-hold target torque obtained by correction is more in line with actual parking requirements, that is, the accuracy of the hill-hold target torque obtained by correction is higher, so that the phenomenon of vehicle rolling caused by the initial value of the hill-hold torque being incorrect and being unable to match the actual parking requirements of the vehicle can be avoided, and thus the safety during the parking process of the vehicle can be improved. BRIEF DESCRIPTION OF DRAWINGS

[0025] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the related art, the drawings needed to be used in the description of the embodiments of the present application or the related art will be briefly introduced. Obviously, the drawings in the following description are only some embodiments of the present application, and other related drawings can be obtained by those skilled in the art without creative labor.

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

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

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

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

[0030] Figure 5 is a structural diagram of a new energy vehicle provided by an embodiment of the present application. Detailed Implementation

[0031] 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.

[0032] First, a brief explanation of the terms / nouns used in the embodiments of this application will be given.

[0033] 1. Parking Torque

[0034] 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 achieving the appropriate target 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 while improving efficiency.

[0035] 2. Maximum recoverable torque of the motor

[0036] 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.

[0037] 3. Wheel end torque

[0038] Wheel-end torque refers to the torque applied to the wheels of a car, typically transmitted to the wheels by an electric motor through the drivetrain. It directly affects a vehicle's acceleration, traction, and braking performance. In new energy vehicles, wheel-end torque is a crucial indicator for evaluating power and functionality, influencing range and energy efficiency. Properly controlling wheel-end torque helps improve the driving experience and energy utilization efficiency.

[0039] 4. Speed ​​fluctuation

[0040] The swiftness of a vehicle's speed is the rate of change of acceleration, a physical quantity that describes how quickly acceleration changes over time.

[0041] 5, Drive (D)

[0042] D represents the forward gear of the vehicle, in general, the motor should rotate forward at this time, and the motor speed should be positive; if the motor rotates backward at this time, it indicates that the motor has reversed.

[0043] 6, Three-dimensional coordinate system of the vehicle

[0044] The three directions in the three-dimensional coordinate system of the vehicle are: the lateral direction x refers to the left and right directions of the vehicle; the longitudinal direction y refers to the front and rear directions of the vehicle, and the up and down directions (vertical direction) of the vehicle are the z direction; wherein, the combination of lateral velocity and longitudinal velocity is the speed of the vehicle.

[0045] The application scenario of the vehicle parking control method provided by the embodiment of the present application will be introduced as follows. Figure 1 , please refer to Figure 1 , Figure 1 is a schematic diagram of an application scenario of a vehicle parking control method provided by the embodiment of the present application. As Figure 1 shown, the vehicle 100 includes a cabin software system 101, a vehicle telematics terminal T-BOX 102, a vehicle controller 103, a traditional braking system 104, a power battery system 105, a motor and a motor controller 106, etc. connected through a bus 107.

[0046] The cabin 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, to provide the interaction function of the driver and the passenger.

[0047] The T-BOX 102, as a remote information processing unit of the vehicle, can connect the vehicle and the cloud through a communication network, and is responsible for collecting, uploading and remotely controlling the vehicle data.

[0048] The vehicle controller 103, as the brain of the new energy vehicle, is responsible for coordinating and controlling the operation of the battery, motor, motor controller, thermal management system and other components, realizing the intelligent control of the power distribution, energy management and vehicle function of the vehicle.

[0049] The traditional braking system 104 includes a traditional brake system, which 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 the main power source for the vehicle and to provide power for the motor during driving.

[0051] The motor and the motor controller 106, wherein the motor is a core component that converts electrical energy into mechanical energy to provide power when the vehicle is running, 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 to enable the motor to accelerate, decelerate and brake. Specifically, the motor controller can change the working state of the motor by adjusting the current and voltage to determine whether the motor drives the vehicle forward or recovers energy.

[0052] 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, vehicle braking is achieved by converting electrical energy into mechanical energy, which involves energy recovery and brake control. Energy recovery can be understood as the motor controller controlling the motor to generate reverse torque to convert the kinetic energy of the vehicle into electrical energy and store it in the battery when the vehicle is decelerating or parking, thereby extending the range. This control method can reduce the dependence on traditional mechanical brakes. Correspondingly, the electric braking process can be understood as a 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, the electric braking function can be activated to give the motor the maximum recovery torque, so that the vehicle is parked through the motor. In the embodiments of the present application, the vehicle 100 can determine the initial hill-hold torque when the electric braking function of the vehicle is activated, and correct the initial hill-hold torque based on the target correction factor corresponding to the hill-slope speed change rate and the hill-slope frequency of the vehicle when it is hill-sloping on the current road surface to obtain the target hill-hold torque. Then, under the condition that the preset parking condition is met, the motor is controlled based on the target hill-hold torque until the vehicle is parked. In this way, during the parking process of the vehicle, the initial hill-hold torque is corrected based on the target correction factor corresponding to the actual driving condition of the vehicle (the hill-slope speed change rate and the hill-slope frequency of the vehicle when it is hill-sloping on the current road surface), so that the target hill-hold torque obtained by correction is more in line with the actual parking demand, i.e. the accuracy of the target hill-hold torque obtained by correction is higher, thereby avoiding the phenomenon of vehicle rolling caused by the initial value of the hill-hold torque being inaccurate and unable to match the actual parking demand of the vehicle, and improving the safety of the vehicle during parking.

[0054] The vehicle parking control method provided by the embodiments of the present application is described below.

[0055] Please refer to Figure 2 , Figure 2is a flowchart of a vehicle parking control method provided by an embodiment of the present application. The method can be executed by a vehicle controller, or can be executed by the vehicle controller and the motor and motor controller in cooperation, etc. For the convenience of description, the present application takes the vehicle controller (for example, the vehicle controller 103 in the vehicle 100 shown in FIG. 1) executing the vehicle parking control method as an example for description. As shown in FIG. 1, the vehicle parking control method can include but is not limited to the following steps: Figure 1 Figure 2

[0056] S201, determining a hill-hold initial torque in a case where an electric braking function of the vehicle is activated.

[0057] In the present application, the electric braking function can be pre-configured in the vehicle, and the activation condition of the electric braking function. The electric braking function can be understood as a function of controlling the vehicle braking based on the above-mentioned electric braking system, and in the case of activating the function, the traditional braking system can be replaced to realize the vehicle deceleration and parking. The activation condition of the electric braking function can include one or more conditions.

[0058] In the electric braking function, the motor is the same as the motor in the conventional driving process of the vehicle, which can be understood as that the electric braking function and the vehicle driving function belong to two working modes of the motor. The motor can be switched to the electric braking function mode or exit the electric braking function mode and be switched to the vehicle driving function mode based on the pre-set activation condition and return condition of the electric braking function.

[0059] In the present application, the hill-hold initial torque can be understood as the motor torque initially determined for hill-holding of the vehicle in the case where the electric braking function of the vehicle is activated.

[0060] In an optional embodiment, during the driving of the vehicle, the vehicle controller can acquire the state information of the vehicle in real time or periodically, determine whether the activation condition of the electric braking function is met based on one or more of the state information, activate the electric braking function if it is determined that the activation condition is met, control the motor by the deceleration torque (or dynamic torque) to realize the deceleration of the vehicle after activating the electric braking function, and further determine a hill-hold initial torque.

[0061] For example, during the driving of the vehicle, the vehicle controller can acquire the state information of the vehicle in real time, match the state information with the activation condition of the electric braking function to determine whether the activation condition of the electric braking function is met. The vehicle controller can activate the electric braking function in the case where it is determined that the activation condition of the electric braking function is met, control the motor by the deceleration torque to realize the deceleration of the vehicle, and determine a hill-hold initial torque.

[0062] ​​Optionally, the vehicle controller determines the initial hill-hold torque based on the current vehicle speed and the slope of the road on which the vehicle is located. The initial hill-hold torque can be determined by looking up a table, or the current vehicle speed and the slope of the road on which the vehicle is located can be input into a pre-constructed model to determine the initial hill-hold torque, and the like, which is not limited herein. The table mentioned above includes a plurality of corresponding relationships between vehicle speed and slope combinations and a plurality of initial hill-hold torques. Optionally, the table can be a table pre-stored in the vehicle controller, or a table pre-stored in a database and readable by the vehicle controller, and the like, which is not limited herein.

[0063] S202, obtain the hill-slip speed change rate and the hill-slip frequency of the vehicle when the vehicle is slipping on the current road.

[0064] The hill-slip refers to the phenomenon of the vehicle sliding down an inclined slope. Optionally, the vehicle controller can determine whether the vehicle is hill-slip by comparing the vehicle speed change rate with a pre-set minimum vehicle speed change rate threshold. For example, if the vehicle speed change rate is less than the pre-set minimum vehicle speed change rate threshold, the vehicle controller can determine that the vehicle is hill-slip.

[0065] The hill-slip speed change rate can be information or data representing the speed change of the vehicle during hill-slip, which can be positive or negative, for example, the hill-slip speed change rate can be negative when hill-slip occurs in the rear (the vehicle is in the uphill stage), and the hill-slip speed change rate can be positive when hill-slip occurs in the front (the vehicle is in the downhill stage), and the like, which is not limited herein. Optionally, the hill-slip speed change rate can be calculated by the vehicle controller based on the wheel speed or the driving motor speed of the vehicle at different times when the vehicle is hill-slip on the current road, and the derivative based on the speed is determined, which is not limited herein.

[0066] The hill-slip frequency refers to the number of times of hill-slip during deceleration hill-hold. Optionally, the hill-slip frequency can be detected by the vehicle controller in real time when the vehicle enters the current road.

[0067] In an optional embodiment, the vehicle controller can detect whether hill-slip occurs during the process of controlling the vehicle to decelerate based on the deceleration torque, and record the hill-slip speed change rate and the hill-slip frequency of the vehicle when the vehicle is hill-slip on the current road when it is determined that the detection result is hill-slip.

[0068] S203, obtain the target correction factor corresponding to the hill-slip speed change rate and the hill-slip frequency, correct the initial hill-hold torque based on the target correction factor, and obtain the target hill-hold torque.

[0069] The target correction factor refers to a correction factor for correcting the initial hill-hold torque.

[0070] Optionally, the vehicle controller obtains the target correction factor corresponding to the hill-start speed variation rate and the hill-start frequency, which can be determined based on the hill-start speed variation rate and the hill-start frequency through a table lookup method, or obtained by inputting the hill-start speed variation rate and the hill-start frequency into a pre-constructed correction factor determination model, which is not limited here. The above-mentioned table includes a plurality of corresponding relationships between combinations of hill-start speed variation rates and hill-start frequencies and a plurality of correction factors. The correction factor is positively correlated with the absolute value of the hill-start speed variation rate in the combination, and the correction factor is positively correlated with the hill-start frequency in the combination. Optionally, the table can be a table pre-set in the vehicle controller, or a table pre-set in a certain database and readable by the vehicle controller, etc., which is not limited here.

[0071] In the process of controlling the vehicle deceleration based on the deceleration torque, the vehicle controller can occur multiple hill-starts. In this case, the vehicle controller needs to dynamically determine the target correction factor corresponding to the hill-start speed variation rate and the hill-start frequency obtained each time the vehicle starts, and dynamically determine the hill-start target torque based on the target correction factor corresponding to the latest hill-start.

[0072] In an optional embodiment, the vehicle controller corrects the hill-start initial torque based on the target correction factor to obtain the hill-start target torque, which can include: performing a product operation on the target correction factor and the hill-start initial torque to obtain the hill-start target torque.

[0073] S204, in the case where the preset parking condition is met, controlling the motor based on the hill-start target torque until the vehicle completes parking.

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

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

[0076] In the embodiments of the present application, the vehicle controller determines the initial hill-hold torque when the electric braking function of the vehicle is activated, obtains the hill-slope speed change rate and the hill-slope frequency when the vehicle is hill-sloping on the current road surface, obtains the target correction factor corresponding to the hill-slope speed change rate and the hill-slope frequency, corrects the initial hill-hold torque based on the target correction factor to obtain the target hill-hold torque, and controls the motor based on the target hill-hold torque when the preset parking condition is met until the vehicle is parked. By using the method, the vehicle can correct the initial hill-hold torque based on the target correction factor corresponding to the hill-slope speed change rate and the hill-slope frequency when the vehicle is hill-sloping on the current road surface to obtain the target hill-hold torque, and control the motor based on the target hill-hold torque when the preset parking condition is met until the vehicle is parked. In this way, the target hill-hold torque obtained by correcting the initial hill-hold torque based on the target correction factor corresponding to the actual driving condition of the vehicle (the hill-slope speed change rate and the hill-slope frequency when the vehicle is hill-sloping on the current road surface) is more in line with the actual parking demand, that is, the accuracy of the target hill-hold torque obtained by correction is higher, so that the phenomenon of vehicle rolling caused by the initial value of the hill-hold torque being inaccurate and unable to match the actual parking demand of the vehicle can be avoided, and thus the safety during the parking process of the vehicle can be improved.

[0077] In an alternative embodiment, Figure 2 In the vehicle parking control method shown, the vehicle controller determines the initial hill-hold torque when the electric braking function of the vehicle is activated, which can include: when the electric braking function of the vehicle is activated, if the preset slope updating condition is met, determining the slope of the current road surface of the vehicle based on the speed change rate of the vehicle in a preset time period, the current wheel end torque, the vehicle mass, and the current ground speed, and updating the previously determined slope based on the slope.

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

[0079] The vehicle speed change rate can be information or data representing a change in vehicle speed, which can be positive or negative, for example, the vehicle speed change rate can be negative when the vehicle speed decreases, and the vehicle speed change rate can be positive when the vehicle speed increases. Alternatively, the vehicle speed change rate can be determined by the vehicle controller based on data captured by sensors in the vehicle, such as an acceleration sensor, or can be determined based on other methods, for example, by calculating the vehicle speed at different times based on wheel speed or vehicle drive motor speed to determine the vehicle speed change rate, which is not limited here.

[0080] The current wheel end torque can be the torque applied to the vehicle wheels detected by the vehicle controller.

[0081] The target wheel end torque can be the torque applied to the vehicle wheels required to bring the vehicle to a stationary state.

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

[0083] In some embodiments, based on the vehicle speed change rate of the vehicle in the preset time period, the current wheel end torque, the vehicle mass, and the current vehicle speed on the ground, the slope of the road on which the vehicle is currently located is determined, comprising: based on the vehicle speed change rate of the vehicle in the preset time period and the current wheel end torque, looking up a table (denoted as a first correspondence table) to obtain an initial slope of the road 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 vehicle speed on the ground, correcting the corrected slope to obtain the slope of the road on which the vehicle is currently located.

[0084] The first corresponding relationship table can include a plurality of combinations of vehicle speed change rates and wheel end torques and corresponding relationships between a plurality of initial slopes. Alternatively, the first corresponding relationship can be a table preset in the vehicle controller, or a table preset in a database and readable by the vehicle controller, and the like, which is not limited herein. Exemplarily, the first corresponding relationship table can be shown in Table 1 as follows.

[0085] Table 1

[0086]

[0087] In Table 1, a positive slope value represents an uphill slope, and a negative slope value represents a downhill slope. As can be seen from Table 1, in a case where the vehicle ground speed changes from positive deceleration to 0 (i.e., the vehicle speed change rate is negative), if the vehicle speed change rate is constant, the greater the absolute value of the wheel end torque, the greater the absolute value of the determined initial slope. In a case where the vehicle ground speed changes from negative to 0 (i.e., the vehicle speed change rate is positive), if the vehicle speed change rate is constant, the greater the absolute value of the wheel end torque, the smaller the absolute value of the determined initial slope. In this way, the initial slope of the road surface currently occupied by the vehicle can be determined simply and efficiently by table lookup.

[0088] Alternatively, the vehicle controller can correct the initial slope based on a first correction factor corresponding to the vehicle mass to obtain a corrected slope, which can include: obtaining the vehicle mass, and obtaining the first correction factor corresponding to the vehicle mass based on the vehicle mass by table lookup (denoted as a second corresponding relationship table); and taking the product of the first correction factor and the initial slope as the corrected slope. In this way, the phenomenon that the vehicle speed change rate is different due to the difference in vehicle mass, thereby causing the slope of the road surface currently occupied by the vehicle to be determined to have an error, can be avoided, and the accuracy of the slope of the road surface currently occupied by the vehicle determined can be improved.

[0089] The second corresponding relationship table includes corresponding relationships between a plurality of vehicle masses and a plurality of correction factors, and the vehicle mass and the correction factor are negatively correlated. Alternatively, the second corresponding relationship can be a table preset in the vehicle controller, or a table preset in a database and readable by the vehicle controller, and the like, which is not limited herein. Exemplarily, the second corresponding relationship table can be shown in Table 2 as follows.

[0090] Table 2

[0091]

[0092] In Table 2, the empty load mass refers to the mass of the vehicle in an empty vehicle condition, and the full load mass refers to the mass of the vehicle in a condition where the vehicle is fully loaded. As can be seen from Table 2, the greater the vehicle mass, the greater the torque required for braking, and therefore the smaller the first correction factor. The first correction factor for correcting the initial slope can be determined simply and efficiently by table lookup.

[0093] Optionally, the vehicle controller corrects the corrected slope based on the second correction factor corresponding to the current ground speed of the vehicle to obtain the slope of the road currently traveled by the vehicle, which can include: obtaining the second correction factor corresponding to the current ground speed of the vehicle based on a table (denoted as a third correspondence table) of the current ground speed; and taking the product of the second correction factor and the corrected slope as the slope of the road currently traveled by the vehicle. In this way, the situation that the slope of the road currently traveled by the vehicle is determined to have an error due to the difference in vehicle speed, which leads to different vehicle speed change rates, can be avoided, and the accuracy of the determined slope of the road currently traveled by the vehicle is improved.

[0094] In the third correspondence table, a plurality of vehicle speeds and a plurality of correction factors are included, and the vehicle speed and the correction factor are negatively correlated. Optionally, the third correspondence table 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 as shown in Table 3.

[0095] Table 3

[0096]

[0097] As can be seen from Table 3, the greater the ground speed of the vehicle, the smaller the correction factor. Through the table lookup method, the second correction factor for correcting the corrected slope can be determined simply and efficiently.

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

[0099] Optionally, when the vehicle controller determines the vehicle speed based on the current motor speed, the tire radius, the speed ratio, and the conversion coefficient, the following formula (1) can be used.

[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: meters); i represents the speed ratio; and μ represents the conversion coefficient between the motor speed and the vehicle speed.

[0102] With the embodiment, the vehicle controller determines the slope of the road where the vehicle is currently located based on the vehicle speed variation rate of the vehicle in the preset time period, the current wheel end torque, the vehicle mass and the current ground speed of the vehicle if the preset slope updating condition is met when the electric braking function of the vehicle is activated, and updates the previously determined slope based on the slope. Based on the updated slope, the initial slope holding torque is determined. In this way, the error in the determined slope caused by the different vehicle mass and current ground speed of the vehicle can be avoided, and the accuracy of the determined slope of the road where the vehicle is currently located is improved. Therefore, in the process of updating the previously determined slope based on the real-time determined slope with high accuracy and determining the initial slope holding torque based on the updated slope (i.e. the real-time determined slope with high accuracy), the accuracy of the determined initial slope holding torque can be improved.

[0103] In an alternative embodiment, Figure 2 In the vehicle parking control method, the vehicle controller obtains the target correction factor corresponding to the hill-start speed variation rate and the hill-start frequency, which can include: determining the target correction factor corresponding to the hill-start speed variation rate and the hill-start frequency based on a preset correspondence relationship; the preset correspondence relationship includes a correspondence relationship between a plurality of combinations of hill-start speed variation rates and hill-start frequencies and a plurality of correction factors; the correction factor is positively correlated with the hill-start speed variation rate in the combination, and the correction factor is positively correlated with the hill-start frequency in the combination.

[0104] Alternatively, the preset correspondence relationship can be a table (denoted as a fourth correspondence table) preset in the vehicle controller, or a table (denoted as a fourth correspondence table) preset in a certain database and readable by the vehicle controller, etc., which is not limited here. In the fourth correspondence table, a correspondence relationship between a plurality of combinations of hill-start speed variation rates and hill-start frequencies and a plurality of correction factors is included; the correction factor is positively correlated with the absolute value of the hill-start speed variation rate in the combination, and the correction factor is positively correlated with the hill-start frequency in the combination. For example, the fourth correspondence table can be as shown in Table 4.

[0105] Table 4

[0106]

[0107] The greater the absolute value of the hill-start speed variation rate, the faster the hill-start, and the greater the hill-start frequency, the less accurate the hill-start torque. Therefore, as can be seen from Table 2, the greater the absolute value of the hill-start speed variation rate and the greater the hill-start frequency, the greater the determined target correction factor. For example, when the hill-start speed variation rate is 0 m / s 2 and the hill-start frequency is 0, the target correction factor is 1; and when the hill-start speed variation rate is 2 m / s 2 and the hill-start frequency is 1, the target correction factor is 2.

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

[0109] In an optional implementation, Figure 2 In the vehicle parking control method shown, the vehicle controller can also activate the electric brake function under at least one of the following conditions:

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

[0111] (2) a second condition that the number of key presses for 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 front vehicle is less than a preset relative distance threshold, and the relative speed is greater than a preset relative speed threshold.

[0113] Wherein, the target control can be a physical or virtual key inside the vehicle, and the association between the target key and the electric brake function is predefined. The target key can be a special key for activating or closing the electric brake function, or it can also be used to activate or close the electric brake function under certain operating conditions by adding configuration while realizing other functions.

[0114] That is, the vehicle controller can activate the electric brake 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 length threshold corresponding to the target control is 1s, and the key length of the driver for the target control is 2s, the vehicle controller can determine that the key length 2s for the target control exceeds the preset length threshold 1s, and in this case, it can be determined that there is a deceleration intention, at which time the vehicle controller can activate the electric brake function.

[0116] For example, assuming that the preset time period is 1s, the preset number threshold of the key press for the target control in 1s is 2 times, and the number of the key press for the target control by the driver in 1s is 3 times, the vehicle control unit can determine that the number of the key press for the target control in 1s is 3 times, which is greater than the preset number threshold of the key press of 2 times. In this case, it can be determined that there is a deceleration intention. At this time, the vehicle control unit can activate the electric brake function.

[0117] For example, assuming that the preset relative distance threshold is 20m, the preset relative speed threshold is 50km / h, and the relative distance between the vehicle and the front vehicle is 18m and the relative speed is 55km / h, the vehicle control unit can determine that the relative distance between the vehicle and the front vehicle 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, it can be determined that there is a collision risk. At this time, the vehicle control unit can activate the electric brake function.

[0118] Optionally, the vehicle control unit can also exit the electric brake function when it is determined that at least one of the following conditions is met: (1) the accelerator pedal opening is greater than the preset proportion value; (2) the relative distance between the vehicle and the front vehicle is greater than the preset distance threshold and the relative speed is less than the preset distance threshold.

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

[0120] For example, assuming that the preset relative distance threshold is 30m, the preset relative speed threshold is 20km / h, and the relative distance between the vehicle and the front vehicle is 31m and the relative speed is 8km / h, the vehicle control unit can determine that the relative distance between the vehicle and the front vehicle 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 collision risk. At this time, the vehicle control unit can exit the electric brake function.

[0121] By using this embodiment, the vehicle control unit can determine under what circumstances the electric brake function is activated, so that the electric brake function can be activated in time when the triggering condition of activating the electric brake function is detected, and thus it is beneficial to control the vehicle braking in time.

[0122] The overall process of the vehicle parking control method provided by the embodiment of the application will be described below. Figure 3 The overall process of the vehicle parking control method provided by the embodiment of the application will be described below. Figure 3 , Figure 3 is a flowchart of another vehicle parking control method provided by the embodiment of the application, which can be executed by the vehicle control unit. As shown inFigure 3 As shown, the vehicle parking control method can include but is not limited to the following steps.

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

[0124] S302, calculating the current vehicle speed based on the motor speed.

[0125] In an alternative embodiment, the vehicle controller can use the aforementioned formula (1) when calculating the vehicle speed based on the motor speed, which will not be described here.

[0126] Based on the vehicle speed and the current vehicle driving direction, the ground speed of the vehicle can be obtained. The driving direction can be forward or reverse; the forward direction is the direction of the vehicle head. In some possible embodiments, the driving direction of the vehicle can be determined by the positive and negative of the motor speed, i.e. forward and reverse, for example, the positive motor speed can correspond to the forward driving direction, and the negative motor speed can correspond to the reverse driving direction. Exemplarily, V Direction represents the vehicle driving direction, when the motor speed is less than-50rpm, the driving direction is reverse, then V Direction is equal to-1, when the motor speed is greater than 50rpm, the driving direction is forward, V Direction is equal to 1, of course, the motor speed threshold value here can also take other values, in order to ensure the accuracy of the judgment, the threshold value is generally not close to 0.

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

[0128] Exemplarily, the vehicle controller can also activate the electric brake function under at least one of the following conditions: (1) the button length for the target control exceeds the preset time threshold value 1s; (2) the number of button presses for the target control within the preset time period (1s) exceeds the preset button press threshold value 2; (3) the relative distance between the vehicle and the front vehicle is less than the preset relative distance threshold value 1m and the relative speed is greater than the preset relative speed threshold value 20m / s.

[0129] Exemplarily, the vehicle controller can also exit the electric brake function under at least one of the following conditions: (1) the throttle opening is greater than 20%; (2) the relative distance between the vehicle and the front vehicle is greater than the preset relative distance threshold value 3m and the relative speed is less than the preset relative speed threshold value 10m / s.

[0130] S304, determining the slope of the road surface where the vehicle is located based on the vehicle speed variation rate, the current wheel end torque, the vehicle mass and the current ground speed of the vehicle.

[0131] The basic principle is as follows: the vehicle controller takes the vehicle speed change rate as the abscissa and the current wheel end torque as the ordinate to look up a table (such as Table 1 described above) to calculate the initial slope, obtains the real road slope through the test equipment, and calibrates and matches the lookup slope to the real slope. The matching mode is to preferentially match the current wheel end torque generated by the vehicle speed change rate 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 is proved that the current road has a slope.

[0132] To avoid different vehicle speed change rates caused by different vehicle masses, the vehicle mass is selected to correct the slope. Alternatively, the vehicle controller can determine a first correction factor for correcting the initial slope based on a vehicle mass lookup table (such as Table 2 described above), and take the product of the first correction factor and the initial slope as the corrected slope. Further, to avoid different vehicle speed change rates caused by different vehicle speeds, the vehicle speed is selected to correct the corrected slope again. Alternatively, the vehicle controller can determine a second correction factor for correcting the corrected slope based on a current ground speed lookup table (such as Table 3 described above), and take the product of the second correction factor and the corrected slope as the slope of the road on which the vehicle is currently located.

[0133] The vehicle controller can take 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, based on the vehicle speed change rate, the target wheel end torque, the current wheel end torque, and the current ground speed, a slope updating mechanism is established.

[0135] Alternatively, if the following conditions are met, it means that the vehicle has entered a steady state stage, and the lookup table calculation of the slope value is more accurate, and the slope updating condition is as follows:

[0136] ① Based on the vehicle speed change rate, the vehicle speed jerk is calculated, and when the absolute value is less than a set threshold of 0.1 m / s 3 and remains for a period of time 100 ms, it means that the current vehicle has entered a steady state stage;

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

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

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

[0140] If the above four conditions are met, it can be determined that the slope update condition is met. Considering that the slope will not change rapidly, when the slope is updated for the first time, the rising edge triggers the filtering process to avoid the sudden change affecting the control effect.

[0141] To avoid the error use of the slope, the scenario only guarantees that the vehicle speed is controllable on the slope, and finally the vehicle needs to be parked on a flat road, i.e., when the function is exited, the slope needs to be cleared to ensure that the vehicle can be safely stationary on the flat road.

[0142] S306, based on the electric braking function flag, the slope, the current vehicle speed on the ground, the maximum available regenerative torque of the motor, the deceleration torque and the initial hill-hold torque are determined.

[0143] The deceleration torque refers to the torque of the vehicle in a dynamic state. The main target of the deceleration torque is deceleration, which can be dynamically adjusted according to the deceleration demand. The deceleration torque can occur at various speeds of the vehicle and is not limited to use at stop.

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

[0145] Optionally, the initial hill-hold torque can be determined by the vehicle controller based on the slope and the current vehicle speed on the ground by looking up a table or by inputting the slope and the current vehicle speed on the ground into a pre-constructed initial hill-hold torque determination model. Here, no limitation is made.

[0146] S307, a self-learning mechanism is introduced to correct the initial hill-hold torque to obtain the target hill-hold torque.

[0147] Considering that the hill-hold demand torque of the vehicle is inconsistent under different loads, to avoid the hill-hold torque being too small to cause the vehicle to roll down the slope, a self-learning mechanism is set up. Taking the D gear as an example, if the following conditions are met, the self-learning mechanism is allowed to run:

[0148] ① When the vehicle is on an uphill, the vehicle rolls backward, indicating that the parking torque is too small.

[0149] ② When the vehicle is on a downhill, the vehicle rolls forward, indicating that the parking torque is too small.

[0150] Under the condition that the self-learning mechanism is running, the initial hill-hold torque is corrected based on the vehicle performance on the slope to obtain the target hill-hold torque. The greater the absolute value of the rolling speed change rate is, the faster the rolling is, and the more the rolling times are, the less accurate the rolling torque is. Optionally, the vehicle controller can determine the target correction factor for correcting the initial hill-hold torque by taking the rolling speed change rate as the horizontal coordinate and the rolling times as the vertical coordinate (such as Table 4), and the product of the target correction factor and the initial hill-hold torque is taken as the target hill-hold torque.

[0151] S308, in the case where the preset parking condition is met, controlling the motor based on the hill-hold target torque until the vehicle completes parking.

[0152] In the embodiments of the present application, the whole vehicle controller can determine the activation flag of the electric brake function based on the key state, the accelerator opening degree, the relative distance, and the relative speed; determine the slope of the road on which the vehicle is located based on the vehicle speed variation rate, the current wheel end torque, the whole vehicle mass, and the current ground speed of the vehicle; set up a slope updating mechanism based on the vehicle speed variation rate, the target wheel end torque, the current wheel end torque, and the current ground speed of the vehicle; in the case where the electric brake function flag is determined to be activated, determine the deceleration torque and the hill-hold initial torque based on the slope, the current ground speed of the vehicle, and the maximum recoverable torque of the motor, and introduce a self-learning mechanism to correct the hill-hold initial torque to obtain the hill-hold target torque; and finally, in the case where the preset parking condition is met, control the motor based on the hill-hold target torque until the vehicle completes parking. In this way, by updating the slope in real time during the parking process of the vehicle, a more accurate slope can be obtained, and thus a more accurate hill-hold initial torque can be determined based on the more accurate slope. Then, by introducing the self-learning mechanism to correct the more accurate hill-hold initial torque, a more accurate hill-hold target torque can be obtained, and thus, in the case where the preset parking condition is met, the motor can be controlled based on the hill-hold target torque until the vehicle completes parking, thereby improving the safety of the electric brake process of the vehicle.

[0153] It should be understood that, although each step in the flowchart involved in each of the above-described embodiments is shown in sequence according to the indication of the arrow, these steps are not necessarily executed in sequence according to the indication of the arrow. Unless otherwise specified herein, the execution of these steps is not strictly limited in sequence, and these steps can be executed in other sequences. Moreover, at least part of the steps in the flowchart involved in each of the above-described embodiments can include multiple steps or stages, which are not necessarily executed at the same time, but can be executed at different times, and the execution sequence of these steps or stages is not necessarily sequential, but can be executed in rotation or alternation with at least part of other steps or stages or steps or stages in other steps.

[0154] Based on the same inventive concept, the embodiments of the present application also provide a vehicle parking control device for implementing the above-mentioned vehicle parking control method. The implementation scheme for solving the problem provided by the device is similar to the implementation scheme described in the above method, and therefore the specific limitations in one or more vehicle parking control device embodiments provided below can refer to the limitations of the vehicle parking control method described above, which will not be described here again.

[0155] Please refer to Figure 4 , Figure 4Fig. 1 is a structural schematic diagram of a vehicle parking control device provided by an embodiment of the present application. As shown in Fig. 1, the vehicle parking control device can include but is not limited to: Figure 4

[0156] The determination module 401 is configured to determine the initial slope parking torque when the electric braking function of the vehicle is activated.

[0157] The acquisition module 402 is configured to acquire the slope sliding speed change rate and the slope sliding frequency of the vehicle when the vehicle is sliding on the current road surface.

[0158] The acquisition and correction module 403 is configured to acquire a target correction factor corresponding to the slope sliding speed change rate and the slope sliding frequency, correct the initial slope parking torque based on the target correction factor, and obtain a target slope parking torque.

[0159] The torque control module 404 is configured to control the motor based on the target slope parking torque until the vehicle completes parking when the preset parking condition is met.

[0160] In one embodiment, when the determination module 401 is configured to determine the initial slope parking torque when the electric braking function of the vehicle is activated, it is specifically configured to: when the electric braking function of the vehicle is activated, if a preset slope update condition is met, determine the slope of the current road surface of the vehicle based on the speed change rate of the vehicle in a preset time period, the current wheel end torque, the vehicle mass, and the current ground speed of the vehicle, and update the previously determined slope based on the slope; determine the initial slope parking torque based on the updated slope.

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

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

[0163] In one embodiment, the obtaining module 402 is further configured to obtain a current motor speed, a tire radius, a speed ratio and a conversion coefficient between the motor speed and the vehicle speed of the vehicle; and the determining module 401 is further configured to determine the vehicle speed of the vehicle based on the current motor speed, the tire radius, the speed ratio and the conversion coefficient; and determine the current ground speed based on the vehicle speed and a driving direction of the vehicle.

[0164] In one embodiment, when the obtaining and correcting module 403 is used to obtain the target correction factor corresponding to the hill-start speed change rate and the hill-start frequency, it is specifically configured to: determine the target correction factor corresponding to the hill-start speed change rate and the hill-start frequency based on a first corresponding relationship; the first corresponding relationship includes a corresponding relationship between a plurality of combinations of the hill-start speed change rate and the hill-start frequency and a plurality of correction factors; the correction factor is positively correlated with the hill-start speed change rate in the combination, and the correction factor is positively correlated with the hill-start frequency in the combination.

[0165] In one embodiment, the device can further include an electric brake function management module, which is configured to activate the electric brake function when at least one of the following conditions is met: a first condition that a key pressing time of a target control of the vehicle is greater than a preset time 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; and a third condition that a relative distance between the vehicle and a front vehicle is less than a preset relative distance threshold, and a relative speed is greater than a preset relative speed threshold.

[0166] The above vehicle parking control device can be realized by software, hardware and a combination thereof. The above modules can be embedded in or independent of the processor in the computer device in hardware form, or can be stored in the memory in the vehicle control device in software form, so as to be called and executed by the processor.

[0167] In one exemplary embodiment, a new energy vehicle is provided, and an internal structure diagram of the new energy vehicle can be as shown in FIG. 1. Figure 5The new energy vehicle includes a processor, a memory, an input / output interface, a communication interface, a display unit and an input device. 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. The processor of the new energy vehicle is configured 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 running the operating system and the computer program in the non-volatile storage medium. The input / output interface of the new energy vehicle is configured to exchange information between the processor and external devices. The communication interface of the new energy vehicle is configured to perform wired or wireless communication with external terminals, and the wireless communication can be implemented through WIFI, a mobile cellular network, NFC (near field communication) or other technologies. The computer program is executed by the processor to implement the vehicle parking control method. The display unit of the new energy vehicle is configured 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. The input device of the new energy vehicle can be a touch layer overlaid on the display screen, or a key, a trackball or a touchpad arranged in the new energy vehicle.

[0168] Those skilled in the art can understand that Figure 5 The structure shown in the figure is only a block diagram of 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 can include more or fewer components than those shown in the figure, or combine certain components, or have a different component arrangement.

[0169] In an exemplary embodiment, the present application provides a new energy vehicle including a memory and a processor. The memory stores a computer program. The processor executes the computer program to implement the steps of the vehicle parking control method.

[0170] In an exemplary embodiment, the present application provides a computer readable storage medium having a computer program stored thereon. The computer program is executed by a processor to implement the steps of the vehicle parking control method.

[0171] In an exemplary embodiment, the present application provides a computer program product including a computer program. The computer program is executed by a processor to implement the steps of the vehicle parking control method.

[0172] It should be noted that the data involved in the present application (including but not limited to hill-holding initial torque, hill-sloping speed change rate, hill-sloping frequency, target correction factor, hill-holding 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 related data need to comply with relevant regulations.

[0173] It can be understood by those skilled in the art that all or part of the processes in the above-mentioned embodiment methods can be completed by instructing related hardware through a computer program. The computer program can be stored in a non-volatile computer readable storage medium, and when executed, can include the processes of the above-mentioned embodiments of each method. Any reference to memory, database or other medium used in each embodiment provided by 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), magnetoresistive 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 but not limitation, RAM can be in various forms, such as static random access memory (SRAM) or dynamic random access memory (DRAM), etc. The database involved in each embodiment provided by the present application can include at least one of a relational database and a non-relational database. The non-relational database can include a distributed database based on a block chain, etc., without being limited thereto. The processor involved in each embodiment provided by the present application can be a general-purpose processor, a central processing unit, a graphics processing unit, a digital signal processor, a programmable logic device, a data processing logic device based on quantum computing, an artificial intelligence (AI) processor, etc., without being limited thereto.

[0174] Any technical features in the above embodiments can be combined, and for the sake of brevity, not all possible combinations are described above, however, any combination of these technical features is deemed to be within the scope of the present application.

[0175] The above embodiments only express several implementation manners of the present application, and the description is relatively specific and detailed, but it should not be understood as a limitation on the patent scope of the present application. It should be pointed out that, for ordinary skilled persons in the art, several modifications 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 should be subject to the appended claims.

Claims

1. A vehicle parking control method, characterized in that, The method includes: Determine the initial parking torque when the vehicle's electric braking function is activated; Obtain the rate of change of vehicle speed and the number of times the vehicle rolls down a slope on the current road surface; Obtain the target correction factor corresponding to the rate of change of the vehicle speed on the slope and the number of times the vehicle has slid down the slope, and correct the initial torque for parking on the slope based on the target correction factor to obtain the target torque for parking on the slope; When the preset parking conditions are met, the motor is controlled based on the target torque for parking on the slope until the vehicle is parked.

2. The method according to claim 1, characterized in that, With the vehicle's electric braking function activated, determine the initial parking torque, including: When the vehicle's electric braking function is activated, if the preset slope update conditions are met, the slope of the road surface where the vehicle is currently located is determined based on the vehicle's 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 the slope is determined based on the updated slope.

3. The method according to claim 2, characterized in that, The method further includes: When the vehicle's electric braking function is activated, the vehicle speed change rate and the current wheel-end torque are acquired; The speed jerk of the vehicle is obtained by differentiating the rate of change of vehicle speed. The preset slope update condition is determined to be satisfied 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 a preset duration, the absolute value of the difference between the target wheel-end torque and the current wheel-end torque is less than a preset threshold, the current wheel-end torque is less than a preset torque threshold, and the vehicle's current ground speed is greater than a preset speed threshold.

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

5. The method according to claim 2, characterized in that, The current ground speed is determined in the following way: Obtain the vehicle's current motor speed, tire radius, speed ratio, and the conversion coefficient between motor speed and vehicle speed; The vehicle speed is determined based on the current motor speed, tire radius, speed ratio, and conversion coefficient. The current ground speed is determined based on the vehicle speed and the vehicle's direction of travel.

6. The method according to claim 1, characterized in that, The step of obtaining the target correction factor corresponding to the rate of change of the vehicle speed on the slope and the number of slopes includes: Based on a preset correspondence, target correction factors are determined for the rate of change of vehicle speed on the slope and the number of slopes. The preset correspondence includes the correspondence between multiple combinations of the rate of change of vehicle speed on the slope and the number of slopes and multiple correction factors. The correction factors are positively correlated with the rate of change of vehicle speed on the slope in the combination and positively correlated with the number of slopes 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: The first condition is that the key press duration of the target control of the vehicle exceeds a preset duration threshold. The second condition is that the number of key presses on the target control within a preset time period is greater than a preset threshold number. The third condition is 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.

8. A vehicle parking control device, characterized in that, The device includes: The determination module is used to determine the initial parking torque when the vehicle's electric braking function is activated; The acquisition module is used to acquire the rate of change of vehicle speed and the number of times the vehicle rolls down a slope on the current road surface. The acquisition and correction module is used to acquire the target correction factor corresponding to the rate of change of the vehicle speed on the slope and the number of times the vehicle has been on the slope, and to correct the initial torque of the vehicle on the slope based on the target correction factor to obtain the target torque of the vehicle on the slope. The torque control module is used to control the motor based on the target torque for parking on the slope, when the preset parking conditions are 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, it implements the steps of the method according to any one of claims 1 to 7.

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

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