A vehicle parking control method, device and vehicle

Abstract

The application discloses a vehicle parking control method, device and vehicle. The method comprises the following steps: when the accelerator of the vehicle is released, setting the speed integral term, the acceleration integral term, the first integral coefficient and the second integral coefficient of the speed control strategy to zero; in each speed control period, determining the output value of the speed control strategy according to the target speed and the actual speed of the motor in the current speed control period, and controlling the motor to decelerate according to the output value of the speed control strategy; when the actual speed of the motor is less than the preset speed and the target speed is zero, setting the first integral coefficient and the second integral coefficient to be non-zero; in each speed control period, determining the output value of the speed control strategy according to the value of the speed proportional term, the value of the speed integral term and the value of the acceleration integral term, and controlling the motor to operate according to the output value of the speed control strategy until the actual speed of the motor is zero. The technical scheme of the application can better control the vehicle to park on a slope and a flat ground.

Description

Technical Field

[0001] This invention relates to the field of vehicle control technology, and in particular to a vehicle parking control method, device, and vehicle. Background Technology

[0002] With the rapid development of new energy technologies, electric vehicles are being used more and more widely.

[0003] Electric vehicles include electric industrial vehicles. In some implementations, electric industrial vehicles do not have mechanical brakes. After the accelerator is released, that is, after the accelerator is no longer pressed, the vehicle decelerates to a final target speed of zero until the vehicle speed is reduced to zero, at which point the electromagnetic brake applies the braking.

[0004] However, vehicles are prone to sliding when parked on a slope, and to rolling back and forth when parked on flat ground. Some vehicles cannot distinguish between driving on a slope and driving on flat ground. If the vehicle is guaranteed to park on a slope, it cannot be guaranteed not to roll back when parked on flat ground; that is, it cannot adequately handle both conditions. Therefore, existing vehicle control methods have limitations in effectively controlling vehicle parking. Summary of the Invention

[0005] This invention provides a vehicle parking control method, device, and vehicle to solve the problem that existing vehicle control methods cannot effectively control vehicle parking.

[0006] According to one aspect of the present invention, a vehicle parking control method is provided, the vehicle parking control method comprising:

[0007] When the vehicle's accelerator is released, the speed integral term and acceleration integral term of the speed control strategy are set to zero, and the first integral coefficient of the speed integral term and the second integral coefficient of the acceleration integral term are set to zero; wherein, the speed control strategy includes a speed proportional term, a speed integral term, and an acceleration integral term;

[0008] In each speed control cycle, the output value of the speed control strategy is determined based on the target speed and the actual speed of the motor corresponding to the current speed control cycle, and the motor is controlled to decelerate based on the output value of the speed control strategy.

[0009] When the actual speed of the motor is less than the preset speed and the target speed is zero, the first integral coefficient and the second integral coefficient are not zero.

[0010] In each rotation speed control period, a value of an acceleration integral term corresponding to the current rotation speed control period is determined according to a value of an acceleration integral term corresponding to a previous rotation speed control period, an actual acceleration of the vehicle corresponding to the current rotation speed control period, a target acceleration and the second integral coefficient, and a value of the output of the rotation speed control strategy is determined according to a value of a rotation speed proportional term corresponding to the current rotation speed control period, a value of a rotation speed integral term and the value of the acceleration integral term, and the motor is controlled to operate according to the value of the output of the rotation speed control strategy until the actual rotation speed of the motor is zero.

[0011] Optionally, the determining, in each rotation speed control period, the value of the output of the rotation speed control strategy according to the target rotation speed corresponding to the current rotation speed control period and the actual rotation speed of the motor includes:

[0012] In each rotation speed control period, a value of an acceleration integral term corresponding to the current rotation speed control period is determined according to a value of an acceleration integral term corresponding to a previous rotation speed control period, an actual acceleration of the vehicle corresponding to the current rotation speed control period, a target acceleration and the second integral coefficient, and a value of the output of the rotation speed control strategy is determined according to a value of a rotation speed proportional term corresponding to the current rotation speed control period, a value of a rotation speed integral term and the value of the acceleration integral term, and the motor is controlled to operate according to the value of the output of the rotation speed control strategy until the actual rotation speed of the motor is zero.

[0013] A difference between the target rotation speed corresponding to the current rotation speed control period and the actual rotation speed of the motor is multiplied by a proportional coefficient to obtain the value of the rotation speed proportional term;

[0014] A product of the value of the rotation speed proportional term corresponding to the current rotation speed control period and the first integral coefficient is added to a value of a rotation speed integral term corresponding to a previous rotation speed control period to obtain the value of the rotation speed integral term;

[0015] A sum of the value of the rotation speed proportional term corresponding to the current rotation speed control period, the value of the rotation speed integral term and the value of the acceleration integral term is taken as the output of the rotation speed control strategy corresponding to the current rotation speed control period.

[0016] Optionally, the determining, in each rotation speed control period, the value of the output of the rotation speed control strategy according to the target rotation speed corresponding to the current rotation speed control period and the actual rotation speed of the motor includes:

[0017] In each rotation speed control period, an instruction rotation speed corresponding to the current rotation speed control period is determined according to a target rotation speed of a previous rotation speed control period minus a preset deceleration;

[0018] If the instruction rotation speed is less than the actual rotation speed of the motor, the instruction rotation speed corresponding to the current rotation speed control period is taken as the target rotation speed corresponding to the current rotation speed control period;

[0019] if the instruction speed is greater than or equal to the actual speed of the motor, then the target speed corresponding to the current speed control period is the actual speed of the motor;

[0020] the difference between the target speed corresponding to the current speed control period and the actual speed of the motor is multiplied by a proportional coefficient to obtain an output value of the speed control strategy.

[0021] Optionally, after determining the output value of the speed control strategy according to the value of the speed proportional term, the value of the speed integral term and the value of the acceleration integral term corresponding to the current speed control period, and controlling the motor to operate according to the output value of the speed control strategy, before the actual speed of the motor is zero, the method further comprises:

[0022] if the actual speed of the motor is less than the first speed threshold for a preset time length, then in each speed control period, the value of the acceleration integral term corresponding to the current speed control period is the value of the acceleration integral term corresponding to the previous speed control period, so as to maintain the value of the acceleration integral term.

[0023] determining the output value of the speed control strategy according to the value of the speed proportional term, the value of the speed integral term and the value of the acceleration integral term corresponding to the current speed control period, and controlling the motor to operate according to the output value of the speed control strategy until the actual speed of the motor is zero.

[0024] Optionally, after controlling the motor to operate according to the output value of the speed control strategy until the actual speed of the motor is zero, the method further comprises:

[0025] if the actual speed of the motor is greater than the second speed threshold, then in each speed control period, the difference between the target acceleration and the actual acceleration of the vehicle corresponding to the current speed control period is multiplied by the second integral coefficient, and the value of the acceleration integral term corresponding to the previous speed control period is added to obtain the value of the acceleration integral term corresponding to the current speed control period, and the output value of the speed control strategy is determined according to the value of the speed proportional term, the value of the speed integral term and the value of the acceleration integral term corresponding to the current speed control period, and the motor is controlled to operate according to the output value of the speed control strategy until the actual speed of the motor is zero.

[0026] Optionally, before determining the value of the acceleration integral term corresponding to the current speed control period according to the value of the acceleration integral term corresponding to the previous speed control period, the actual acceleration of the vehicle corresponding to the current speed control period, the target acceleration and the second integral coefficient, the method further comprises:

[0027] According to the actual rotating speed of the motor corresponding to the current rotating speed control period and the actual rotating speed of the motor corresponding to the rotating speed control period before the preset period number, the actual acceleration of the vehicle corresponding to the current rotating speed control period is determined.

[0028] Optionally, the determining of the actual acceleration of the vehicle corresponding to the current rotating speed control period according to the actual rotating speed of the motor corresponding to the current rotating speed control period and the actual rotating speed of the motor corresponding to the rotating speed control period before the preset period number comprises:

[0029] In each rotating speed control period, the actual rotating speed of the motor is acquired, and the actual rotating speed is sequentially stored into storage data according to corresponding time sequence; wherein the storage data comprises a preset number of digits, and the preset number is the preset period number plus one.

[0030] After the number of acquired actual rotating speeds reaches the preset number, the first count value is controlled to be the preset period number, and the second count value is controlled to be zero.

[0031] In each rotating speed control period, after the actual rotating speed of the motor corresponding to the current rotating speed control period is acquired, the first count value and the second count value are controlled to be increased by one respectively.

[0032] If the first count value is greater than the preset period number, the first count value is controlled to be zero.

[0033] If the second count value is greater than the preset period number, the second count value is controlled to be zero.

[0034] The first count value is taken as a first target digit number of the storage data, and the second count value is taken as a second target digit number of the storage data.

[0035] The actual rotating speed of the motor corresponding to the current rotating speed control period is stored into the first target digit number of the storage data.

[0036] The difference between the value corresponding to the first target digit number of the storage data and the value corresponding to the second target digit number of the storage data is divided by the time length corresponding to the preset period number, so as to obtain the actual acceleration of the vehicle corresponding to the current rotating speed control period.

[0037] Optionally, the controlling of the rotating speed integral term and the acceleration integral term of the rotating speed control strategy to be zero comprises:

[0038] The rotating speed integral term of the rotating speed control strategy is controlled to be reduced to zero, and the acceleration integral term is controlled to be reduced to zero.

[0039] According to another aspect of the present application, a vehicle parking control device is provided, which comprises:

[0040] The first control module is configured to set the speed integral term and the acceleration integral term of the speed control strategy to zero and set a first integral coefficient of the speed integral term and a second integral coefficient of the acceleration integral term to zero when the accelerator of the vehicle is released, wherein the speed control strategy comprises a speed proportional term, a speed integral term and an acceleration integral term;

[0041] The first motor control module is configured to determine the output value of the speed control strategy according to the target speed corresponding to the current speed control period and the actual speed of the motor in each speed control period, and control the motor to decelerate according to the output value of the speed control strategy.

[0042] The second control module is configured to set the first integral coefficient and the second integral coefficient to be non-zero when the actual speed of the motor is less than a preset speed and the target speed is zero.

[0043] The second motor control module is configured to determine the value of the acceleration integral term corresponding to the current speed control period according to the value of the acceleration integral term corresponding to the previous speed control period, the actual acceleration of the vehicle corresponding to the current speed control period, the target acceleration and the second integral coefficient, and determine the output value of the speed control strategy according to the value of the speed proportional term corresponding to the current speed control period, the value of the speed integral term and the value of the acceleration integral term, and control the motor to operate according to the output value of the speed control strategy until the actual speed of the motor is zero.

[0044] According to another aspect of the present application, a vehicle is provided, which comprises the vehicle parking control device according to any one of the embodiments of the present application.

[0045] The technical scheme of the embodiment of the present application is that when the accelerator of the vehicle is released, the speed integral term and the acceleration integral term of the speed control strategy are set to zero, and the first integral coefficient of the speed integral term and the second integral coefficient of the acceleration integral term are set to zero, then in each speed control period, the output value of the speed control strategy is determined according to the target speed corresponding to the current speed control period and the actual speed of the motor, and the motor is controlled to decelerate according to the output value of the speed control strategy. When the actual speed of the motor is less than the preset speed and the target speed is zero, the first integral coefficient and the second integral coefficient of the acceleration integral term are set to be non-zero, then in each speed control period, the value of the acceleration integral term corresponding to the current speed control period is determined according to the value of the acceleration integral term corresponding to the previous speed control period, the actual acceleration of the vehicle corresponding to the current speed control period, the target acceleration and the second integral coefficient, and the output value of the speed control strategy is determined according to the value of the speed proportional term corresponding to the current speed control period, the value of the speed integral term and the value of the acceleration integral term, and the motor is controlled to operate according to the output value of the speed control strategy until the actual speed of the motor is zero. Since when the first integral coefficient and the second integral coefficient of the acceleration integral term are set to be non-zero, the target speed is zero, the actual speed of the motor is greater than zero and less than the preset speed, and the speed proportional term is negative, the accumulated speed integral term is less than zero. Since the vehicle is decelerating, the actual acceleration of the vehicle is negative, and the target acceleration of the vehicle is zero, the accumulated acceleration integral term is positive after the second integral coefficient is set to be non-zero. In this way, if the vehicle is on a slope, the absolute value of the actual acceleration of the vehicle is large due to the influence of gravity, so that the absolute value of the acceleration integral term is large and the absolute value of the speed integral term is small, so that after the actual speed of the motor is zero, the value of the acceleration integral term after offsetting the value of the speed integral term is positive, and the motor can also provide positive torque, thereby maintaining the vehicle on the slope and avoiding the vehicle from rolling down the slope. If the vehicle is on a flat ground, the absolute value of the actual acceleration of the vehicle is small, and the absolute value of the acceleration integral term of the vehicle is close to the absolute value of the speed integral term, so that the value after offsetting the acceleration integral term and the speed integral term is close to or equal to zero, thereby ensuring that the output value of the speed control strategy is zero after the actual speed of the motor is zero, and ensuring that the vehicle can be parked stably without rolling back. In this way, whether the vehicle is parked on a slope or on a flat ground, the vehicle can be parked stably, thereby improving the accuracy of the vehicle parking control and better controlling the vehicle to park on a slope or on a flat ground.

[0046] It should be understood that the content described in this part is not intended to identify key or important features of the embodiments of the present application, nor to limit the scope of the present application. Other features of the present application will become apparent from the following description. BRIEF DESCRIPTION OF DRAWINGS

[0047] In order to make the technical solutions in the embodiments of the present application clearer, the accompanying drawings needed in the embodiments description will be briefly introduced as follows. Obviously, the accompanying drawings in the following description only represent some embodiments of the present application, and other drawings can be obtained by those skilled in the art without any creative effort on the basis of these drawings.

[0048] Figure 1 is a flow chart of a vehicle parking control method provided by an embodiment of the present application;

[0049] Figure 2 is a flow chart of another vehicle parking control method provided by an embodiment of the present application;

[0050] Figure 3 is a flow chart of still another vehicle parking control method provided by an embodiment of the present application;

[0051] Figure 4 is a flow chart of yet another vehicle parking control method provided by an embodiment of the present application;

[0052] Figure 5 is a structural schematic diagram of a vehicle parking control device provided by an embodiment of the present application. DETAILED DESCRIPTION

[0053] In order to make the technical solutions in the embodiments of the present application clearer, the accompanying drawings needed in the embodiments description will be briefly introduced as follows. Obviously, the accompanying drawings in the following description only represent some embodiments of the present application, and other drawings can be obtained by those skilled in the art without any creative effort on the basis of these drawings.

[0054] It should be noted that the terms "first", "second", and the like in the description and claims of the present application and the above-mentioned accompanying drawings are used to distinguish similar objects, and do not necessarily indicate a specific order or sequence. It should be understood that the data thus used can be interchanged under appropriate circumstances, so that the embodiments of the present application described herein can be implemented in an order other than that illustrated or described herein. In addition, the terms "include" and "have" and any variations thereof are intended to cover non-exclusive inclusion, for example, a process, method, system, product or device that includes a series of steps or units does not necessarily have to be limited to those steps or units clearly listed, but can include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0055] The embodiment of the present application provides a vehicle parking control method, which can be executed by a vehicle parking control device.

[0056] Figure 1 is a flow chart of a vehicle parking control method provided by the embodiment of the present application, referring to Figure 1 , the vehicle parking control method comprises the following steps.

[0057] S110, when the accelerator of the vehicle is released, the speed integral term and the acceleration integral term of the speed control strategy are zero, and the first integral coefficient of the speed integral term and the second integral coefficient of the acceleration integral term are zero; wherein the speed control strategy comprises a speed proportional term, a speed integral term and an acceleration integral term.

[0058] The vehicle comprises an electric vehicle, and the electric vehicle comprises an electric industrial vehicle, for example, an electric forklift, an electric dumper and an electric golf cart. The vehicle comprises a motor, and the motor drives the vehicle to run. The vehicle further comprises an accelerator, when the accelerator is stepped on, the motor accelerates or runs at a constant speed, after the accelerator is released, the motor starts to decelerate until the motor speed is zero, and the vehicle stops. The speed control strategy can be a proportional integral control strategy. The speed control strategy comprises a speed proportional term, a speed integral term and an acceleration integral term, that is, the output value of the speed control strategy is the sum of the value of the speed proportional term, the value of the speed integral term and the value of the acceleration integral term. The speed proportional term can reflect the deviation between the target speed of the motor and the actual speed, and the speed integral term can reflect the accumulated deviation between the actual speed of the motor and the target speed. The acceleration integral term can reflect the accumulated deviation between the actual acceleration of the vehicle and the target acceleration. After the accelerator is released, the target acceleration of the vehicle is zero.

[0059] Specifically, before the acceleration of the vehicle is released, i.e. after the accelerator of the vehicle is stepped on, the vehicle accelerates or accelerates first and then runs at a constant speed. When the vehicle accelerates or runs at a constant speed, the acceleration integral term can be zero. When the vehicle accelerates, the target speed of the motor is greater than the actual speed of the motor, so that the deviation of the target speed of the motor minus the actual speed is greater than zero, the value of the speed proportional term of the speed control strategy is greater than zero, and the speed integral term reflects the cumulative deviation of the actual speed of the motor from the target speed, so the speed integral term is greater than zero. Even if the motor runs at a constant speed later, the cumulative speed integral term is still greater than zero. When the motor decelerates, the output value of the speed control strategy needs to be negative to provide a reverse torque (a torque opposite to that when the motor accelerates) to the motor, so the speed integral term greater than zero is not conducive to the motor deceleration, so the speed integral term is set to zero and the first integral coefficient of the speed integral term is set to zero, so that the speed integral term is no longer accumulated, avoiding affecting the motor deceleration. And the acceleration integral term is zero, the second integral coefficient of the acceleration integral term is zero, which can avoid the influence of the acceleration integral term on the motor deceleration.

[0060] S120, in each speed control period, determining the output value of the speed control strategy according to the target speed corresponding to the current speed control period and the actual speed of the motor, and controlling the motor to decelerate according to the output value of the speed control strategy.

[0061] Wherein, the speed control strategy outputs an output value for each speed control period.

[0062] Specifically, after the speed integral term and the acceleration integral term of the speed control strategy are set to zero and the first integral coefficient of the speed integral term is set to zero when the accelerator of the vehicle is released, and before the actual speed of the motor is less than the preset speed and the target speed is zero, the speed control period is started to be executed in a loop to control the motor to decelerate, i.e. in each speed control period, the output value of the speed control strategy is determined according to the target speed corresponding to the current speed control period and the actual speed of the motor, and the motor is controlled to decelerate according to the output value of the speed control strategy.

[0063] After the accelerator is released, in each speed control period, the target speed corresponding to the current speed control period can be obtained by subtracting a preset deceleration from the target speed of the previous speed control period. According to the target speed corresponding to the current speed control period and the actual speed of the motor, the deviation between the target speed and the actual speed can be determined, and the value of the speed proportional term can be determined. Since the speed integral term and the acceleration integral term are zero, the value of the speed proportional term is the output value of the speed control strategy.

[0064] Or, due to the action of external force (force other than the torque provided by the motor, such as gravity, etc.), the motor actually decelerates faster, and the target speed obtained by subtracting the preset deceleration from the previous speed control period is greater than the actual speed of the motor. The target speed corresponding to the current speed control period is controlled to be the actual speed, so that the output value of the speed control strategy is zero, and the motor is freely decelerated by relying on external force (such as gravity) to make the motor decelerate.

[0065] The output value of the speed control strategy can be used as the target current of the current control strategy. The target current and the actual current of the motor are substituted into the current control strategy to obtain the output value of the current control strategy. The output value of the current control strategy is pulse width modulated and output to the control electrode of the power transistor in the voltage conversion circuit (such as an inverter circuit) connected to the motor, thereby controlling the torque voltage value output to the motor, and thereby controlling the actual speed of the motor to reach or approach the target speed. In this way, the motor gradually decelerates until the speed of the motor reaches the preset speed.

[0066] The current control strategy can be a proportional integral control strategy, and the current control strategy can include a current proportional term and a current integral term. The difference between the target current and the actual current is multiplied by the current proportional coefficient to obtain the value of the current proportional term. The product of the current proportional term corresponding to the current control period and the current integral coefficient is added to the value of the current integral term of the previous current control period to obtain the value of the current integral term of the current control period. The value of the current proportional term under the current control period is added to the value of the current integral term to obtain the output value of the current control strategy.

[0067] S130, when the actual speed of the motor is less than the preset speed and the target speed is zero, the first integral coefficient and the second integral coefficient are not zero.

[0068] The first integral coefficient and the second integral coefficient are both greater than zero.

[0069] Specifically, when the actual speed of the motor is greater than zero and less than the preset speed, and the target speed is zero, it indicates that the actual speed of the motor is small and close to zero. Therefore, the first integral coefficient and the second integral coefficient of the acceleration integral term are controlled to be non-zero, so that the speed integral term and the acceleration integral term can start to accumulate.

[0070] S140, in each speed control period, determining a value of the acceleration integral term corresponding to the current speed control period according to a value of the acceleration integral term corresponding to the previous speed control period, an actual acceleration of the vehicle corresponding to the current speed control period, the target acceleration and the second integral coefficient, and determining an output value of the speed control strategy according to a value of the speed proportional term corresponding to the current speed control period, a value of the speed integral term and the value of the acceleration integral term, and controlling the motor to operate according to the output value of the speed control strategy until the actual speed of the motor is zero.

[0071] wherein the target acceleration of the vehicle is zero after the accelerator is released. For example, the value of the acceleration integral term corresponding to the current speed control period is the product of the difference between the target acceleration and the actual acceleration, the second integral coefficient, and the value of the acceleration integral term corresponding to the previous speed control period. For example, the sum of the value of the speed proportional term corresponding to the current speed control period, the value of the speed integral term and the value of the acceleration integral term is the output value of the speed control strategy corresponding to the current speed control period.

[0072] Specifically, after the first integral coefficient and the second integral coefficient of the acceleration integral term are not zero, the speed control period is continued to be executed in a loop.

[0073] According to the output value of the speed control strategy, the actual speed of the motor is controlled to approach or equal to the target speed, and when the target speed is zero, the actual speed of the motor is zero, so that the vehicle stops.

[0074] Since the target speed is zero when the first integral coefficient and the second integral coefficient of the acceleration integral term are not zero, the actual speed of the motor is greater than zero and less than the preset speed, and the speed proportional term is negative, the speed integral term accumulated after the first integral coefficient is not zero is less than zero. Since the vehicle is running at a deceleration, the actual acceleration of the vehicle is negative, the target acceleration of the vehicle is zero, and the value of the target acceleration minus the actual acceleration is positive, the acceleration integral term accumulated after the second integral coefficient is not zero is positive.

[0075] If the vehicle is on a slope, the absolute value of the actual acceleration of the vehicle is large due to the influence of gravity, so that the absolute value of the acceleration integral term is large, and the absolute value of the speed integral term is small, so that after the value of the acceleration integral term and the value of the speed integral term are offset, there is still a positive value, so that after the actual speed of the motor is zero, the output value of the speed control strategy after the value of the acceleration integral term and the value of the speed integral term are offset is positive, and the motor can also provide positive torque (the torque provided to the motor when the vehicle is driving forward is positive torque), thereby maintaining the vehicle on the slope and avoiding the vehicle from rolling down the slope. If the vehicle is on a flat ground, the absolute value of the actual acceleration of the vehicle is small, and the absolute value of the acceleration integral term of the vehicle and the absolute value of the speed integral term are close, so that the value after the acceleration integral term and the speed integral term are offset is close to or equal to zero, thereby ensuring that the output value of the speed control strategy is zero after the actual speed of the motor is zero, and ensuring that the vehicle can be parked stably and will not roll back. In this way, whether the vehicle is decelerating and parking on a slope or on a flat ground, it can be parked stably, thereby improving the accuracy of the vehicle parking control.

[0076] The technical scheme of the embodiment is that when the accelerator of the vehicle is released, the speed integral term and the acceleration integral term of the speed control strategy are set to zero, and the first integral coefficient of the speed integral term and the second integral coefficient of the acceleration integral term are set to zero, then in each speed control period, the output value of the speed control strategy is determined according to the target speed corresponding to the current speed control period and the actual speed of the motor, and the motor is controlled to decelerate according to the output value of the speed control strategy. When the actual speed of the motor is less than the preset speed and the target speed is zero, the first integral coefficient and the second integral coefficient of the acceleration integral term are set to be non-zero, then in each speed control period, the value of the acceleration integral term corresponding to the current speed control period is determined according to the value of the acceleration integral term corresponding to the previous speed control period, the actual acceleration of the vehicle corresponding to the current speed control period, the target acceleration and the second integral coefficient, and the output value of the speed control strategy is determined according to the value of the speed proportional term corresponding to the current speed control period, the value of the speed integral term and the value of the acceleration integral term, and the motor is controlled to operate according to the output value of the speed control strategy until the actual speed of the motor is zero. Since the target speed is zero when the first integral coefficient and the second integral coefficient of the acceleration integral term are set to be non-zero, the actual speed of the motor is greater than zero and less than the preset speed, and the speed proportional term is negative, the accumulated speed integral term is less than zero. Since the vehicle is decelerating, the actual acceleration of the vehicle is negative, and the target acceleration of the vehicle is zero, the accumulated acceleration integral term is positive after the second integral coefficient is set to be non-zero. In this way, if the vehicle is on a slope, the absolute value of the actual acceleration of the vehicle is large due to the influence of gravity, so that the absolute value of the acceleration integral term is large and the absolute value of the speed integral term is small, so that after the actual speed of the motor is zero, the value of the acceleration integral term after offsetting the value of the speed integral term is positive, and the motor can also provide positive torque, thereby maintaining the vehicle on the slope and avoiding the vehicle from rolling down the slope. If the vehicle is on a flat ground, the absolute value of the actual acceleration of the vehicle is small, and the absolute value of the acceleration integral term of the vehicle is close to the absolute value of the speed integral term, so that the value after offsetting the acceleration integral term and the speed integral term is close to or equal to zero, thereby ensuring that the output value of the speed control strategy is zero after the actual speed of the motor is zero, and ensuring that the vehicle can be parked stably without rolling back. In this way, whether the vehicle is parked on a slope or on a flat ground, the vehicle can be parked stably, thereby improving the accuracy of vehicle parking control and better controlling the vehicle to park on a slope and on a flat ground.

[0077] On the basis of the above technical solutions, optionally, S140, in each rotation speed control period, the value of the acceleration integral term corresponding to the current rotation speed control period is determined according to the value of the acceleration integral term corresponding to the previous rotation speed control period, the actual acceleration of the vehicle corresponding to the current rotation speed control period, the target acceleration and the second integral coefficient, and the output value of the rotation speed control strategy is determined according to the value of the rotation speed proportional term corresponding to the current rotation speed control period, the value of the rotation speed integral term and the value of the acceleration integral term, including:

[0078] Step a1, in each rotation speed control period, the value of the acceleration integral term corresponding to the current rotation speed control period is obtained by subtracting the product of the target acceleration and the second integral coefficient from the actual acceleration of the vehicle corresponding to the current rotation speed control period, and adding the value of the acceleration integral term corresponding to the previous rotation speed control period.

[0079] For example, the target acceleration of the vehicle is Aref, and the second integral coefficient is Ka. For example, the current rotation speed control period is the mth rotation speed control period, m is an integer greater than 1, the actual acceleration of the vehicle corresponding to the current rotation speed control period is , the value of the acceleration integral term corresponding to the current rotation speed control period is , and the value of the acceleration integral term corresponding to the previous rotation speed control period is . Since the target acceleration Aref is zero, the value of the acceleration integral term is .

[0080] Since the vehicle is running at a deceleration, the actual acceleration Afab is negative, and the value of the acceleration integral term is positive.

[0081] Step a2, the value of the rotation speed proportional term is obtained by subtracting the product of the actual rotation speed of the motor and the proportional coefficient from the target rotation speed corresponding to the current rotation speed control period.

[0082] For example, the target rotation speed is Vref, the actual rotation speed of the motor is Vfab, and the proportional coefficient is Kp. The rotation speed proportional term is . For example, the current rotation speed control period is the mth rotation speed control period, m is an integer greater than 1, the target rotation speed corresponding to the current rotation speed control period is , the actual rotation speed corresponding to the current rotation speed control period is , and the value of the rotation speed proportional term corresponding to the current rotation speed control period is . When the target rotation speed is zero, the value of the rotation speed proportional term is negative.

[0083] Step a3, the value of the speed proportional term corresponding to the current speed control period is multiplied by the first integral coefficient, and the value of the speed integral term corresponding to the previous speed control period is added to obtain the value of the speed integral term.

[0084] For example, the first integral coefficient is Ki. For example, the current speed control period is the mth speed control period, m is an integer greater than 1, the value of the speed proportional term corresponding to the current speed control period is , the value of the speed integral term corresponding to the previous speed control period is , and the value of the speed integral term corresponding to the current speed control period is When the target speed is zero, the value of the speed proportional term is negative, and the value of the accumulated speed integral term is negative.

[0085] Step a4, the sum of the value of the speed proportional term, the value of the speed integral term and the value of the acceleration integral term corresponding to the current speed control period is taken as the output value of the speed control strategy corresponding to the current speed control period.

[0086] For example, the speed proportional term is , the speed integral term is , the acceleration integral term is , and the output value of the speed control strategy is Vout, then . For example, the current speed control period is the mth speed control period, the value of the speed proportional term corresponding to the current speed control period is , the value of the speed integral term corresponding to the current speed control period is , the value of the acceleration integral term corresponding to the current speed control period is , and the output value of the speed control strategy corresponding to the current speed control period is .

[0087] On the basis of the above technical solutions, optionally, S120, in each speed control period, the output value of the speed control strategy is determined according to the target speed corresponding to the current speed control period and the actual speed of the motor, comprising:

[0088] Step b1, in each speed control period, the target speed of the previous speed control period is subtracted by a preset deceleration to obtain the command speed corresponding to the current speed control period.

[0089] Specifically, in each speed control period, the command speed corresponding to the current speed control period is obtained by subtracting a preset deceleration from the target speed of the previous speed control period. For example, the current speed control period is the mth speed control period, m is an integer greater than 1, the target speed of the previous speed control period is ​​, preset deceleration is a, then the instruction speed corresponding to the current speed control period is .

[0090] Step b2, if the instruction speed is less than the actual speed of the motor, then the instruction speed corresponding to the current speed control period is taken as the target speed corresponding to the current speed control period.

[0091] Specifically, in each speed control period, the determined instruction speed is compared with the actual speed of the motor, if the instruction speed is less than the actual speed of the motor, then the instruction speed corresponding to the current speed control period is taken as the target speed corresponding to the current speed control period, so that the motor runs at the target speed, thereby making the motor decelerate.

[0092] Step b3, if the instruction speed is greater than or equal to the actual speed of the motor, then the target speed corresponding to the current speed control period is the actual speed of the motor.

[0093] Specifically, in each speed control period, the determined instruction speed is compared with the actual speed of the motor, if the instruction speed is greater than or equal to the actual speed of the motor, it indicates that under the action of external force (such as gravity, etc.), the actual speed of the motor decreases faster, in order to ensure the motor deceleration, the target speed corresponding to the current speed control period is controlled to be the actual speed of the motor, that is, the value of the actual speed is assigned to the target speed, the target speed is equal to the actual speed, and the output value of the speed control strategy is zero, so that the motor relies on the external force (such as gravity, etc.) to freely decelerate.

[0094] Step b4, the difference between the target speed corresponding to the current speed control period and the actual speed of the motor is multiplied by a proportional coefficient, as the output value of the speed control strategy.

[0095] Specifically, the difference between the target speed corresponding to the current speed control period and the actual speed of the motor is multiplied by a proportional coefficient, to obtain the value of the speed proportional term corresponding to the current speed control period. Since the speed integral term, the first integral coefficient and the second integral coefficient are zero, the speed integral term and the acceleration integral term are also zero, so the value of the speed proportional term corresponding to the current speed control period is the output value of the speed control strategy corresponding to the current speed control period.

[0096] On the basis of the above technical solutions, Figure 2 is a flowchart of another vehicle parking control method provided by the embodiment of the application, and optionally, reference can be made to Figure 2 The vehicle parking control method comprises the following steps:

[0097] S210, when the accelerator of the vehicle is released, setting the speed integral term and the acceleration integral term of the speed control strategy to zero, and setting the first integral coefficient of the speed integral term and the second integral coefficient of the acceleration integral term to zero; wherein the speed control strategy comprises a speed proportional term, a speed integral term and an acceleration integral term.

[0098] S220, in each speed control period, determining the output value of the speed control strategy according to the target speed corresponding to the current speed control period and the actual speed of the motor, and controlling the motor to decelerate according to the output value of the speed control strategy.

[0099] S230, when the actual speed of the motor is less than the preset speed and the target speed is zero, setting the first integral coefficient and the second integral coefficient to be non-zero.

[0100] S240, in each speed control period, determining the value of the acceleration integral term corresponding to the current speed control period according to the value of the acceleration integral term corresponding to the previous speed control period, the actual acceleration of the vehicle corresponding to the current speed control period, the target acceleration and the second integral coefficient, and determining the output value of the speed control strategy according to the value of the speed proportional term corresponding to the current speed control period, the value of the speed integral term and the value of the acceleration integral term, and controlling the motor to operate according to the output value of the speed control strategy.

[0101] That is, after setting the first integral coefficient and the second integral coefficient to be non-zero, before the duration that the actual speed of the motor is less than the first speed threshold reaches the preset duration, determining the value of the acceleration integral term corresponding to the current speed control period according to the value of the acceleration integral term corresponding to the previous speed control period, the actual acceleration of the vehicle corresponding to the current speed control period, the target acceleration and the second integral coefficient, and determining the output value of the speed control strategy according to the value of the speed proportional term corresponding to the current speed control period, the value of the speed integral term and the value of the acceleration integral term, and controlling the motor to operate according to the output value of the speed control strategy.

[0102] S250, if the duration that the actual speed of the motor is less than the first speed threshold reaches the preset duration, in each speed control period, setting the value of the acceleration integral term corresponding to the current speed period to be the value of the acceleration integral term corresponding to the previous speed period, so as to maintain the value of the acceleration integral term.

[0103] Wherein, the first speed threshold is less than the preset speed.

[0104] Specifically, after deceleration for a period of time, if the actual speed of the motor is less than the first speed threshold, it indicates that the actual speed of the motor is very small, close to zero. If the duration that the actual speed of the motor is less than the first speed threshold reaches the preset duration, it indicates that the actual speed of the motor may fluctuate around zero, that is, the positive and negative fluctuations occur, that is, after adjusting the speed of the motor according to the target speed of zero, the actual speed of the motor is negative, and after continuing to adjust the speed of the motor according to the target speed of zero, the actual speed of the motor is positive. At this time, the value of the acceleration integral term corresponding to the current speed control period is the value of the acceleration integral term corresponding to the previous speed control period, that is, the value of the acceleration integral term is maintained unchanged, avoiding the problem that the change of the acceleration integral term makes the motor speed fluctuate back and forth, which is beneficial to make the motor speed reach zero as soon as possible and make the vehicle stop stably.

[0105] S260, determining the output value of the speed control strategy according to the value of the speed proportional term, the value of the speed integral term and the value of the acceleration integral term corresponding to the current speed control period, and controlling the motor to operate according to the output value of the speed control strategy until the actual speed of the motor is zero.

[0106] Specifically, after the value of the acceleration integral term is controlled to be unchanged, the value of the speed proportional term and the value of the speed integral term corresponding to the current speed control period are determined according to the target speed of zero, the output value of the speed control strategy is obtained, and the motor is controlled to operate according to the output value of the speed control strategy, that is, the speed control strategy is continuously executed in a loop until the actual speed of the motor is zero, so that the vehicle stops stably.

[0107] It should be noted that after step S240, if the duration that the actual speed of the motor is less than the first speed threshold does not reach the preset duration, the value of the acceleration integral term corresponding to the current speed control period is determined according to the actual acceleration of the vehicle, the target acceleration and the second integral coefficient corresponding to the current speed control period, and the output value of the speed control strategy is determined according to the value of the speed proportional term, the value of the speed integral term and the value of the acceleration integral term corresponding to the current speed control period, and the motor is controlled to operate according to the output value of the speed control strategy until the actual speed of the motor is zero.

[0108] On the basis of the above technical solutions, Figure 3 is a flowchart of another vehicle parking control method provided by an embodiment of the application, which can be optionally combined with Figure 3 , the vehicle parking control method comprises:

[0109] S310, when the accelerator of the vehicle is released, setting the speed integral term and the acceleration integral term of the speed control strategy to zero, and setting the first integral coefficient of the speed integral term and the second integral coefficient of the acceleration integral term to zero; wherein the speed control strategy comprises a speed proportional term, a speed integral term and an acceleration integral term.

[0110] S320, in each speed control period, determining an output value of the speed control strategy according to a target speed corresponding to the current speed control period and an actual speed of the motor, and controlling the motor to slow down according to the output value of the speed control strategy.

[0111] S330, when the actual speed of the motor is less than the preset speed and the target speed is zero, setting the first integral coefficient and the second integral coefficient to be non-zero.

[0112] S340, in each speed control period, determining a value of an acceleration integral term corresponding to the current speed control period according to a value of an acceleration integral term corresponding to a previous speed control period, an actual acceleration of the vehicle corresponding to the current speed control period, a target acceleration and the second integral coefficient, and determining an output value of the speed control strategy according to a value of a speed proportional term corresponding to the current speed control period, a value of a speed integral term and the value of the acceleration integral term, and controlling the motor to operate according to the output value of the speed control strategy.

[0113] S350, if the actual speed of the motor is less than the first speed threshold for a preset time length, in each speed control period, setting the value of the acceleration integral term corresponding to the current speed control period to be the value of the acceleration integral term corresponding to the previous speed control period, so as to maintain the value of the acceleration integral term.

[0114] S360, determining an output value of the speed control strategy according to a value of a speed proportional term corresponding to the current speed control period, a value of a speed integral term and a value of an acceleration integral term, and controlling the motor to operate according to the output value of the speed control strategy until the actual speed of the motor is zero.

[0115] S370, if the actual speed of the motor is greater than the second speed threshold, in each speed control period, obtaining a value of an acceleration integral term corresponding to the current speed control period by subtracting a product of a difference between the target acceleration and an actual acceleration of the vehicle corresponding to the current speed control period and the second integral coefficient from a value of an acceleration integral term corresponding to a previous speed control period, and determining an output value of the speed control strategy according to a value of a speed proportional term corresponding to the current speed control period, a value of a speed integral term and the value of the acceleration integral term, and controlling the motor to operate according to the output value of the speed control strategy until the actual speed of the motor is zero.

[0116] Wherein, the second speed threshold is greater than the first speed threshold.

[0117] Specifically, after maintaining the value of the acceleration integral term unchanged so that the motor speed is zero, the working condition of the vehicle can change (for example, from uphill to flat ground, or the vehicle is uphill on a ramp formed by wooden boards, and the wooden boards change so that the vehicle becomes downhill), so that the actual motor speed is greater than the second speed threshold, indicating that the actual motor speed is greatly different from zero by relying on the adjustment of the speed proportional term and the speed integral term, and the value of the acceleration integral term is continued to be calculated according to the actual acceleration of the vehicle, so that the motor speed is continued to be adjusted according to the actual acceleration of the vehicle, so that the actual motor speed is zero.

[0118] Since the actual motor speed is greater than the second speed threshold, the actual acceleration of the vehicle is positive, and the value of the target acceleration minus the actual acceleration is negative, so that the absolute value of the acceleration integral term decreases or becomes negative. The speed proportional term is negative, the speed integral term is negative, and the absolute value of the acceleration integral term decreases or becomes negative, so that the speed control strategy is a negative value with a larger absolute value, so that the motor decelerates faster, which is beneficial to make the actual motor speed zero and make the vehicle stop stably.

[0119] It should be noted that in step S370, if the actual motor speed is greater than the second speed threshold, the difference between the target acceleration and the actual acceleration of the vehicle corresponding to the current speed control period is multiplied by the second integral coefficient, and the value of the acceleration integral term corresponding to the previous speed control period is added to obtain the value of the acceleration integral term corresponding to the current speed control period. The output value of the speed control strategy is determined according to the value of the speed proportional term corresponding to the current speed control period, the value of the speed integral term and the value of the acceleration integral term, and after the motor is controlled to operate according to the output value of the speed control strategy, if the actual motor speed is less than the first speed threshold again for a preset time, the value of the acceleration integral term corresponding to the current speed period is the value of the acceleration integral term corresponding to the previous speed period, so as to maintain the value of the acceleration integral term. The output value of the speed control strategy is determined according to the value of the speed proportional term corresponding to the current speed control period, the value of the speed integral term and the value of the acceleration integral term, and the motor is controlled to operate according to the output value of the speed control strategy, that is, step S350 is returned to be executed, until the actual motor speed is zero, so as to ensure that the vehicle stops stably.

[0120] On the basis of the above technical solutions, Figure 4 is a flowchart of another vehicle parking control method provided by an embodiment of the present application, and optionally, referring to Figure 4 , the vehicle parking control method comprises:

[0121] S410, when the accelerator of the vehicle is released, setting the speed integral term and the acceleration integral term of the speed control strategy to zero, and setting the first integral coefficient of the speed integral term and the second integral coefficient of the acceleration integral term to zero; wherein the speed control strategy comprises a speed proportional term, a speed integral term and an acceleration integral term.

[0122] S420, in each speed control period, determining the output value of the speed control strategy according to the target speed corresponding to the current speed control period and the actual speed of the motor, and controlling the motor to decelerate according to the output value of the speed control strategy.

[0123] S430, when the actual speed of the motor is less than the preset speed and the target speed is zero, setting the first integral coefficient and the second integral coefficient to be non-zero.

[0124] S440, determining the actual acceleration of the vehicle corresponding to the current speed control period according to the actual speed of the motor corresponding to the current speed control period and the actual speed of the motor corresponding to the speed control period before the preset period number.

[0125] Specifically, the actual speed of the motor is obtained once in each speed control period. In the current speed control period, the actual speed of the motor corresponding to the current speed control period is subtracted from the actual speed of the motor corresponding to the speed control period before the preset period number, and then divided by the time length corresponding to the preset period number, to obtain the actual acceleration of the motor corresponding to the current speed control period. For example, the preset period number is 19, the current speed control period is the n+19th speed control period, the speed control period before the preset period number is the n th speed control period, the actual speed of the motor corresponding to the n+19 th speed control period is subtracted from the actual speed of the motor corresponding to the n th speed control period, and then divided by the product of 19 and the single period interval time length, to obtain the actual acceleration of the vehicle corresponding to the current speed control period. In this way, the actual acceleration of the vehicle can be determined according to the actual speed of the motor, i.e. the acceleration of the vehicle is related to the acceleration of the motor, and the acceleration of the vehicle is reflected by the acceleration of the motor, so that the value of the acceleration integral term can be determined according to the actual acceleration of the vehicle, and the speed of the motor can be adjusted according to the actual acceleration of the vehicle. Wherein n is a positive integer. Wherein the single period interval time length is the interval time length between two speed control periods, i.e. the output value of the speed control strategy is output once every single period interval time length.

[0126] S450、in each speed control period, determining the value of the acceleration integral term corresponding to the current speed control period according to the value of the acceleration integral term corresponding to the previous speed control period, the actual acceleration of the vehicle corresponding to the current speed control period, the target acceleration and the second integral coefficient, and determining the output value of the speed control strategy according to the value of the speed proportional term corresponding to the current speed control period, the value of the speed integral term and the value of the acceleration integral term, and controlling the motor to operate according to the output value of the speed control strategy until the actual speed of the motor is zero.

[0127] On the basis of the above technical solution, optionally, S440, determining the actual acceleration of the vehicle corresponding to the current speed control period according to the actual speed of the motor corresponding to the current speed control period and the actual speed of the motor corresponding to the speed control period before the preset number of periods, comprising:

[0128] Step c1, in each speed control period, the actual speed of the motor is obtained, and the actual speed is stored in the storage data in the corresponding time sequence; wherein the storage data includes a preset number of digits, and the preset number is one more than the preset period number.

[0129] Specifically, before the number of actual speeds obtained reaches the preset number, the actual acceleration is not calculated. In each speed control period, the actual speed of the motor is obtained, and the actual speed is stored in the storage data in the corresponding time sequence. That is, the actual speed corresponding to the first speed control period is stored as the zeroth bit of the storage data, the actual speed corresponding to the second speed control period is stored as the first bit of the storage data, the actual speed corresponding to the third speed control period is stored as the second bit of the storage data, and so on. The actual speed corresponding to the preset number of speed control periods is stored as the preset number minus one bit of the storage data. In this way, the actual acceleration of the vehicle can be determined according to the storage data.

[0130] Step c2, after the number of actual speeds obtained reaches the preset number, the first count value is controlled to be the preset period number, and the second count value is controlled to be zero.

[0131] Specifically, for example, the preset period number is num, after the number of actual speeds obtained reaches the preset number, the first count value is controlled to be num, and the second count value is controlled to be zero.

[0132] Step c3, in each speed control period, after obtaining the actual speed of the motor corresponding to the current speed control period, the first count value and the second count value are controlled to be one respectively.

[0133] Specifically, after the first count value is controlled to be the preset number of periods and the second count value is controlled to be zero, the actual rotating speed of the motor is continuously acquired in each rotating speed control period, and after the actual rotating speed of the motor is acquired each time, the first count value is increased by one and the second count value is increased by one.

[0134] Step c4, if the first count value is greater than the preset number of periods, the first count value is controlled to be zero.

[0135] Specifically, in each rotating speed control period, after the first count value is increased by one each time, the first count value is judged, if the first count value is less than or equal to the preset number of periods, the first count value is operated again in the next rotating speed control period. If the first count value is greater than the preset number of periods, after the first count value is greater than the preset number of periods, the first count value is controlled to be zero.

[0136] Step c5, if the second count value is greater than the preset number of periods, the second count value is controlled to be zero.

[0137] Specifically, in each rotating speed control period, after the second count value is increased by one each time, the second count value is judged, if the second count value is less than or equal to the preset number of periods, the second count value is operated again in the next rotating speed control period. If the second count value is greater than the preset number of periods, after the second count value is greater than the preset number of periods, the second count value is controlled to be zero.

[0138] Step c6, the first count value is taken as the first target bit number of the storage data, and the second count value is taken as the second target bit number of the storage data.

[0139] Specifically, in each rotating speed control period, the first count value is taken as the first target bit number of the storage data, and the second count value is taken as the second target bit number of the storage data, for example, in the current rotating speed control period, the first count value is 0, and the zeroth bit of the storage data is the first target bit number. The second count value is 1, and the first bit of the storage data is the second target bit number.

[0140] Step c7, the actual rotating speed of the motor corresponding to the current rotating speed control period is stored to the first target bit number of the storage data.

[0141] Specifically, in each rotating speed control period, the actual rotating speed of the motor corresponding to the current rotating speed control period is stored to the first target bit number of the storage data, for example, the current rotating speed control period is the 21st rotating speed control period, the preset number is 20, and the storage data includes the 0th bit to the 19th bit. The first count value is 0, that is, the first target bit number is 0, and the actual rotating speed of the motor corresponding to the 21st rotating speed control period is stored to the 0th bit of the storage data.

[0142] Step c8, subtract the difference value of the value corresponding to the first target bit number of the stored data and the value corresponding to the second target bit number of the stored data, by the time length corresponding to the preset number of periods, to obtain the actual acceleration of the vehicle corresponding to the current speed control period.

[0143] Specifically, in each speed control period, subtract the difference value of the value corresponding to the first target bit number of the stored data and the value corresponding to the second target bit number of the stored data, by the time length corresponding to the preset number of periods (i.e. the product of the preset number of periods and the single period interval time length), to obtain the actual acceleration of the vehicle corresponding to the current speed control period. By cyclically executing steps c2 to c8, the actual acceleration of the vehicle can be calculated in the first preset number of speed control periods and every speed control period thereafter.

[0144] For example, the preset number is 20, and the stored data includes the 0th bit to the 19th bit. In the first speed control period, the actual speed corresponding to the first speed control period is stored as the zeroth bit of the stored data, in the second speed control period, the actual speed corresponding to the second speed control period is stored as the first bit of the stored data, in the third speed control period, the actual speed corresponding to the third speed control period is stored as the second bit of the stored data, and so on. In the twentieth speed control period, the actual speed corresponding to the twentieth speed control period is stored as the nineteenth bit of the stored data. In this way, the filling of the stored data is completed.

[0145] And in the twentieth speed control period, the first count value is controlled to be the preset number of periods, i.e. the first count value is 19, and the second count value is controlled to be 0.

[0146] In the twenty-first speed control period, the actual speed of the motor corresponding to the twenty-first speed control period is obtained, the first count value is incremented by one, the first count value is 20, and the second count value is incremented by one, the second count value is 1.

[0147] The first count value is 20, which is greater than the preset number of periods 19, so the first count value is controlled to be zero, the first target bit number is the zeroth bit, and the actual speed of the motor corresponding to the twenty-first speed control period is stored in the zeroth bit of the stored data. In this way, the bit number in the stored data can be directly replaced, realizing circular storage, without the need for a shift operation, which can save control resources and time.

[0148] When the second count value is 1, the second target bit number is the first bit, that is, the value of the zeroth bit is the actual speed corresponding to the current speed control period, the value of the first bit is the actual speed corresponding to the speed control period before the preset period number, the value of the zeroth bit is subtracted from the value of the first bit, and then divided by the time length corresponding to the preset period number (that is, the product of the preset period number and the single period interval time length), so that the actual acceleration of the vehicle corresponding to the twenty-first speed control period can be obtained. The calculation method of the actual acceleration corresponding to the twenty-second speed control period and each speed control period thereafter is the same as that of the actual acceleration corresponding to the twenty-first speed control period, and will not be described here.

[0149] In addition, after the actual acceleration is determined, the actual acceleration can be converted into Q24 format, that is, the rated acceleration of the vehicle is taken as the reference, that is, , the ratio of the determined actual acceleration to the rated acceleration is multiplied by , so that the actual acceleration can be converted into Q24 format. In this way, the accuracy of the actual acceleration can be improved, and the control accuracy of the motor can be improved.

[0150] On the basis of the above technical solutions, optionally, the speed integral term and the acceleration integral term of the speed control strategy are zero, comprising:

[0151] The speed integral term of the speed control strategy is reduced to zero, and the acceleration integral term is reduced to zero.

[0152] Specifically, the speed integral term and the acceleration integral term can be directly controlled to be zero. Alternatively, the speed integral term of the speed control strategy is gradually reduced to zero according to a preset number of times, and the acceleration integral term is gradually reduced to zero according to a preset number of times. Thus, the speed integral term and the acceleration integral term can be prevented from changing greatly, so that the output value of the speed control strategy changes greatly, which greatly affects the speed of the motor and causes the vehicle to decelerate greatly.

[0153] The embodiment of the application also provides a vehicle parking control device for executing the vehicle parking control method provided by any embodiment of the application. Figure 5 is a structural schematic diagram of a vehicle parking control device provided by the embodiment of the application, referring to Figure 5 , the vehicle parking control device comprises:

[0154] The first control module 101 is configured to set the speed integral term and the acceleration integral term of the speed control strategy to zero when the accelerator of the vehicle is released, and set the first integral coefficient of the speed integral term and the second integral coefficient of the acceleration integral term to zero; wherein the speed control strategy comprises a speed proportional term, a speed integral term and an acceleration integral term.

[0155] The first motor control module 102 is configured to determine an output value of the speed control strategy according to the target speed corresponding to the current speed control period and the actual speed of the motor in each speed control period, and control the motor to slow down according to the output value of the speed control strategy.

[0156] The second control module 103 is configured to set the first integral coefficient and the second integral coefficient to be non-zero when the actual speed of the motor is less than the preset speed and the target speed is zero.

[0157] The second motor control module 104 is configured to determine a value of an acceleration integral term corresponding to the current speed control period according to a value of an acceleration integral term corresponding to the previous speed control period, an actual acceleration of the vehicle corresponding to the current speed control period, a target acceleration and a second integral coefficient, and determine an output value of the speed control strategy according to a value of a speed proportional term corresponding to the current speed control period, a value of a speed integral term and the value of the acceleration integral term, and control the motor to operate according to the output value of the speed control strategy until the actual speed of the motor is zero.

[0158] The vehicle parking control device provided by the embodiments of the present application can perform the vehicle parking control method provided by any of the embodiments of the present application, and has the corresponding function modules and beneficial effects of performing the method.

[0159] The embodiments of the present application also provide a vehicle comprising the vehicle parking control device provided by any of the embodiments of the present application, and therefore the vehicle provided by the embodiments has the same beneficial effects as the vehicle parking control device provided by any of the embodiments of the present application, which will not be repeated here.

[0160] It should be understood that the various forms of flow shown above can be reordered, added or deleted steps. For example, each step described in the present application can be executed in parallel, sequentially or in different order, as long as the desired results of the technical solutions of the present application can be achieved, which is not limited herein.

[0161] The above detailed description does not constitute a limitation on the protection scope of the present application. Those skilled in the art should understand that various modifications, combinations, sub-combinations and substitutions can be made according to design requirements and other factors. Any modifications, equivalent replacements and improvements made within the spirit and principles of the present application shall be included in the protection scope of the present application.

Claims

1. A vehicle parking control method, characterized in that, include: When the vehicle's accelerator is released, the speed integral term and acceleration integral term of the speed control strategy are set to zero, and the first integral coefficient of the speed integral term and the second integral coefficient of the acceleration integral term are set to zero; wherein, the speed control strategy includes a speed proportional term, a speed integral term, and an acceleration integral term; In each speed control cycle, the output value of the speed control strategy is determined based on the target speed and the actual speed of the motor corresponding to the current speed control cycle, and the motor is controlled to decelerate based on the output value of the speed control strategy. When the actual speed of the motor is less than the preset speed and the target speed is zero, the first integral coefficient and the second integral coefficient are not zero. In each speed control cycle, the value of the acceleration integral term corresponding to the current speed control cycle is determined based on the value of the acceleration integral term corresponding to the previous speed control cycle, the actual acceleration of the vehicle corresponding to the current speed control cycle, the target acceleration, and the second integral coefficient. The output value of the speed control strategy is determined based on the value of the speed proportional term, the value of the speed integral term, and the value of the acceleration integral term corresponding to the current speed control cycle. The motor is controlled to run according to the output value of the speed control strategy until the actual speed of the motor is zero. In each speed control cycle, the value of the acceleration integral term corresponding to the current speed control cycle is determined based on the value of the acceleration integral term corresponding to the previous speed control cycle, the actual acceleration of the vehicle corresponding to the current speed control cycle, the target acceleration, and the second integral coefficient. The output value of the speed control strategy is then determined based on the values ​​of the speed proportional term, the speed integral term, and the acceleration integral term corresponding to the current speed control cycle, including: In each speed control cycle, the difference between the target acceleration and the actual acceleration of the vehicle corresponding to the current speed control cycle is multiplied by the second integral coefficient, and the value of the acceleration integral term corresponding to the previous speed control cycle is added to obtain the value of the acceleration integral term corresponding to the current speed control cycle. The product of the difference between the target speed corresponding to the current speed control cycle and the actual speed of the motor and the proportional coefficient is used as the value of the speed proportional term. The value of the speed integral term is obtained by multiplying the value of the speed proportional term corresponding to the current speed control cycle with the first integral coefficient, and adding the value of the speed integral term corresponding to the previous speed control cycle. The sum of the values ​​of the proportional speed term, the integral speed term, and the integral acceleration term corresponding to the current speed control cycle is used as the output value of the speed control strategy corresponding to the current speed control cycle.

2. The method according to claim 1, characterized in that, In each speed control cycle, the output value of the speed control strategy is determined based on the target speed and the actual speed of the motor corresponding to the current speed control cycle, including: In each speed control cycle, the command speed corresponding to the current speed control cycle is obtained by subtracting the preset deceleration from the target speed of the previous speed control cycle. If the commanded speed is less than the actual speed of the motor, then the commanded speed corresponding to the current speed control cycle is taken as the target speed corresponding to the current speed control cycle. If the commanded speed is greater than or equal to the actual speed of the motor, then the target speed corresponding to the current speed control cycle is set to the actual speed of the motor. The product of the difference between the target speed corresponding to the current speed control cycle and the actual speed of the motor, and the proportional coefficient, is used as the output value of the speed control strategy.

3. The method according to claim 1 or 2, characterized in that, After determining the output value of the speed control strategy based on the values ​​of the speed proportional term, speed integral term, and acceleration integral term corresponding to the current speed control cycle, and controlling the motor to run according to the output value of the speed control strategy, before the actual speed of the motor reaches zero, the following steps are also included: If the actual speed of the motor is less than the first speed threshold for a preset duration, then in each speed control cycle, the value of the acceleration integral term corresponding to the current speed cycle is set to the value of the acceleration integral term corresponding to the previous speed cycle, so as to maintain the value of the acceleration integral term. The output value of the speed control strategy is determined based on the values ​​of the speed proportional term, the speed integral term, and the acceleration integral term corresponding to the current speed control cycle. The motor is then controlled to run according to the output value of the speed control strategy until the actual speed of the motor is zero.

4. The method according to claim 3, characterized in that, After controlling the motor to operate according to the output value of the speed control strategy until the actual speed of the motor reaches zero, the process further includes: If the actual speed of the motor is greater than the second speed threshold, then in each speed control cycle, the difference between the target acceleration and the actual acceleration of the vehicle corresponding to the current speed control cycle is multiplied by the second integral coefficient, and the value of the acceleration integral term corresponding to the previous speed control cycle is added to obtain the value of the acceleration integral term corresponding to the current speed control cycle. The output value of the speed control strategy is determined based on the value of the speed proportional term, the value of the speed integral term, and the value of the acceleration integral term corresponding to the current speed control cycle. The motor is controlled to run according to the output value of the speed control strategy until the actual speed of the motor is zero.

5. The method according to claim 1 or 2, characterized in that, Before determining the value of the acceleration integral term corresponding to the current speed control cycle based on the value of the acceleration integral term corresponding to the previous speed control cycle, the actual acceleration of the vehicle corresponding to the current speed control cycle, the target acceleration, and the second integral coefficient, the method further includes: The actual acceleration of the vehicle corresponding to the current speed control cycle is determined based on the actual speed of the motor corresponding to the current speed control cycle and the actual speed of the motor corresponding to the speed control cycle a preset number of cycles ago.

6. The method according to claim 5, characterized in that, The step of determining the actual acceleration of the vehicle corresponding to the current speed control cycle based on the actual speed of the motor corresponding to the current speed control cycle and the actual speed of the motor corresponding to the speed control cycle a preset number of cycles ago includes: In each speed control cycle, the actual speed of the motor is acquired and stored in the storage data in the corresponding time order; wherein, the storage data includes a preset number of digits, the preset number being the preset number of cycles plus one; After the number of actual rotation speeds obtained reaches the preset number, the first count value is controlled to be the preset number of cycles, and the second count value is controlled to be zero. In each speed control cycle, after obtaining the actual speed of the motor corresponding to the current speed control cycle, the first count value and the second count value are incremented by one respectively; If the first count value is greater than the preset number of cycles, then the first count value is controlled to be zero; If the second count value is greater than the preset number of cycles, then the second count value is controlled to be zero; The first count value is used as the first target number of bits of the stored data, and the second count value is used as the second target number of bits of the stored data; Store the actual motor speed corresponding to the current speed control cycle to the first target number of bits of the stored data; The difference between the value corresponding to the first target number of bits of the stored data and the value of the second target number of bits of the stored data is divided by the duration corresponding to the preset number of cycles to obtain the actual acceleration of the vehicle corresponding to the current speed control cycle.

7. The method according to claim 1, characterized in that, The method of setting the speed control strategy's integral terms for both speed and acceleration to zero includes: Reduce the speed integral term of the speed control strategy to zero, and reduce the acceleration integral term to zero.

8. A vehicle parking control device, characterized in that, The vehicle parking control device is used to execute the vehicle parking control method according to any one of claims 1-7, and the vehicle parking control device includes: The first control module is configured to, when the accelerator of the vehicle is released, set the speed integral term and acceleration integral term of the speed control strategy to zero, and set the first integral coefficient of the speed integral term and the second integral coefficient of the acceleration integral term to zero; wherein, the speed control strategy includes a speed proportional term, a speed integral term, and an acceleration integral term; The first motor control module is used to determine the output value of the speed control strategy based on the target speed corresponding to the current speed control cycle and the actual speed of the motor in each speed control cycle, and to control the motor to decelerate based on the output value of the speed control strategy. The second control module is used to ensure that the first integral coefficient and the second integral coefficient are not zero when the actual speed of the motor is less than the preset speed and the target speed is zero. The second motor control module is used to determine the value of the acceleration integral term corresponding to the current speed control cycle in each speed control cycle based on the value of the acceleration integral term corresponding to the previous speed control cycle, the actual acceleration of the vehicle in the current speed control cycle, the target acceleration, and the second integral coefficient. It also determines the output value of the speed control strategy based on the value of the speed proportional term, the value of the speed integral term, and the value of the acceleration integral term corresponding to the current speed control cycle. Finally, it controls the motor to run according to the output value of the speed control strategy until the actual speed of the motor is zero.

9. A vehicle, characterized in that, Includes the vehicle parking control device as described in claim 8.

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