Control method and device for vehicle

Abstract

The present application relates to the technical field of vehicle control, in particular to a control method and device of a vehicle. The method comprises: obtaining a current accelerator pedal opening and a current wheel end actual torque of the vehicle; determining a target state and a current state of the vehicle according to the current accelerator pedal opening and the current wheel end actual torque; if the current state is a driving state and the target state is a recovery state, obtaining a first target motor torque according to a motor speed change rate, a motor actual torque and a driver demand torque when the current wheel end actual torque is in a preset negative zero-crossing interval, and performing torque control on the motor according to the first target motor torque. Thus, through real-time judgment of the zero-crossing interval and torque control on the motor, the balance between power response speed and vehicle impact during acceleration and deceleration is achieved, the driving performance and smoothness of the vehicle are improved, and the user experience is improved.

Description

Technical Field

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

[0002] With the continuous development of new energy vehicles, zero torque transmission is a fundamental and common issue that all new energy vehicles must consider. The vehicle's power system transmits torque from the power source to the wheels through multiple components. Due to the torsional characteristics of these components and the gaps between them, during transitional operating conditions that change according to the driver's intentions, such as instantaneous acceleration or reversing, the driving wheel drives the driven wheel to rotate under the motor's drive. At this time, the driving wheel gear meshes with the driven wheel gear on one side, but there is a large gap on the other side, resulting in overall vehicle vibration and noise. Special processing of the torque change process is required to eliminate the vibration of the transmission system and the impact caused by direct torque changes.

[0003] In related technologies, different filtering methods are usually selected to filter the torque change process according to different modes, conditions, or division intervals. The required torque is divided into different intervals to find the zero-crossing interval, reduce the vehicle impact under transition conditions, and improve the smoothness and drivability of the whole vehicle.

[0004] However, the main problem with the above technical solutions is that judging the zero-crossing state based on motor torque or the driver's required torque requires empirical values ​​or experiments. Since there are certain variations in the state of vehicle system components and torque accuracy, the zero-crossing range is set relatively large to ensure it covers all vehicles, resulting in a significant delay in overall vehicle power delivery. Summary of the Invention

[0005] This invention provides a vehicle control method and device to solve the problem of large vehicle power delay caused by a large zero-crossing range setting in related technologies. By real-time judgment of the zero-crossing range and torque control of the motor, a balance is achieved between the power response speed and vehicle impact during acceleration and deceleration, thereby improving the driving performance and smoothness of the vehicle and enhancing the user experience.

[0006] To achieve the above objectives, a first aspect of the present invention provides a vehicle control method, comprising the following steps:

[0007] Obtain the vehicle's current accelerator pedal opening and current wheel-end torque;

[0008] The target state and current state of the vehicle are determined based on the current accelerator pedal opening and the current actual wheel end torque.

[0009] If the current state is the driving state and the target state is the recovery state, then when the actual torque at the current wheel end is in the preset negative zero-crossing range, the first target motor torque is obtained based on the motor speed change rate, the actual motor torque and the driver's required torque, and the motor torque is controlled based on the first target motor torque.

[0010] According to an embodiment of the present invention, after determining that the current state is the driving state and the target state is the recycling state, the method further includes:

[0011] Determine whether the current actual torque at the wheel end is greater than a first preset torque threshold and whether the current actual torque at the wheel end is less than a second preset torque threshold, wherein the first preset torque threshold is less than the second preset torque threshold;

[0012] If the current wheel end actual torque is greater than the first preset torque threshold and the current wheel end actual torque is less than the second preset torque threshold, then the current wheel end actual torque is determined to be in the preset negative zero-crossing interval.

[0013] According to one embodiment of the present invention, before determining whether the current actual torque at the wheel end is greater than the first preset torque threshold and whether the current actual torque at the wheel end is less than the second preset torque threshold, the method further includes:

[0014] The vehicle is controlled to be in a parking state, and during the process of adjusting the torque of the motor from a first initial value to a first target value based on a first preset rate, the first actual torque when the motor speed meets the first preset fluctuation condition is obtained, and the second actual torque when the motor speed is 0 and there is no fluctuation is obtained.

[0015] The second preset torque threshold is obtained based on the sum of the first actual torque and the first reserved torque, and the first preset torque threshold is obtained based on the difference between the second actual torque and the second reserved torque.

[0016] According to one embodiment of the present invention, obtaining the first target motor torque based on the motor speed change rate, the actual motor torque, and the driver's required torque includes:

[0017] The first motor torque change rate limit value is determined based on the motor speed change rate.

[0018] The limit value for the torque change rate of the second motor is determined based on the actual torque of the motor.

[0019] The limit value for the rate of change of the third motor torque is determined based on the difference between the torque required by the driver and the actual torque of the motor.

[0020] The first target motor torque is obtained by summing the maximum value among the first motor torque change rate limit, the second motor torque change rate limit, and the third motor torque change rate limit with the actual motor torque.

[0021] According to one embodiment of the present invention, after determining the target state and current state of the vehicle based on the current accelerator pedal opening and the current actual wheel-end torque, the method further includes:

[0022] If the current state is the recovery state and the target state is the driving state, then when the actual torque at the current wheel end is in the preset positive zero-crossing range, the second target motor torque is obtained according to the motor speed change rate, the actual motor torque and the driver's required torque, and the motor is torque controlled according to the second target motor torque.

[0023] According to an embodiment of the present invention, after determining that the current state is the recycling state and the target state is the driving state, the method further includes:

[0024] Determine whether the current actual torque at the wheel end is greater than a third preset torque threshold and whether the current actual torque at the wheel end is less than a fourth preset torque threshold, wherein the third preset torque threshold is less than the fourth preset torque threshold;

[0025] If the current wheel end actual torque is greater than the third preset torque threshold and the current wheel end actual torque is less than the fourth preset torque threshold, then the current wheel end actual torque is determined to be in the preset positive zero-crossing interval.

[0026] According to one embodiment of the present invention, before determining whether the current wheel end actual torque is greater than the third preset torque threshold and whether the current wheel end actual torque is less than the fourth preset torque threshold, the method further includes:

[0027] The vehicle is controlled to be in a parking state, and during the process of adjusting the torque of the motor from a second initial value to a second target value based on a second preset rate, a third actual torque is obtained when the motor speed meets the second preset fluctuation condition, and a fourth actual torque is obtained when the motor speed is 0 and there is no fluctuation.

[0028] The third preset torque threshold is obtained based on the difference between the third actual torque and the third reserved torque, and the fourth preset torque threshold is obtained based on the sum of the fourth actual torque and the fourth reserved torque.

[0029] According to one embodiment of the present invention, obtaining the second target motor torque based on the motor speed change rate, the actual motor torque, and the driver's required torque includes:

[0030] The limit value for the torque change rate of the fourth motor is determined based on the motor speed change rate.

[0031] The torque change rate limit value of the fifth motor is determined based on the actual torque of the motor.

[0032] The torque variation rate limit value of the sixth motor is determined based on the difference between the driver's required torque and the actual torque of the motor;

[0033] The second target motor torque is obtained by summing the minimum value among the fourth motor torque change rate limit, the fifth motor torque change rate limit, and the sixth motor torque change rate limit with the actual motor torque.

[0034] According to one embodiment of the present invention, determining the target state and current state of the vehicle based on the current accelerator pedal opening and the current actual wheel-end torque includes:

[0035] Based on the current accelerator pedal opening, determine whether the driver's required torque is greater than or equal to a first preset value;

[0036] If the torque required by the driver is greater than or equal to the first preset value, the target state is determined to be the driving state; otherwise, the target state is determined to be the recovery state.

[0037] Determine whether the current actual torque at the wheel end is less than a second preset value;

[0038] If the actual torque at the current wheel end is less than the second preset value, then the current state is determined to be the recovery state; otherwise, the current state is determined to be the driving state.

[0039] According to the vehicle control method proposed in this embodiment, the current accelerator pedal opening and the current actual wheel torque are obtained, and the target state and current state of the vehicle are determined based on these parameters. When the current state is determined to be a driving state and the target state to be a regenerative braking state, and the current actual wheel torque is within a preset negative zero-crossing range, a first target motor torque is obtained based on the motor speed change rate, the actual motor torque, and the driver's required torque. The motor torque is then controlled based on this first target motor torque. Therefore, by real-time judgment of the zero-crossing range and torque control of the motor, a balance between the power response speed and vehicle impact during acceleration and deceleration is achieved, improving the overall driving performance and smoothness of the vehicle, and enhancing the user experience.

[0040] To achieve the above objectives, a second aspect of the present invention provides a vehicle control device, comprising:

[0041] The acquisition module is used to acquire the vehicle's current accelerator pedal opening and the current actual wheel torque;

[0042] The judgment module is used to determine the target state and current state of the vehicle based on the current accelerator pedal opening and the current actual wheel end torque;

[0043] The control module is configured to, if the current state is a driving state and the target state is a recovery state, obtain a first target motor torque based on the motor speed change rate, the actual motor torque, and the driver's required torque when the actual torque at the current wheel end is in a preset negative zero-crossing range, and then perform torque control on the motor based on the first target motor torque.

[0044] According to an embodiment of the present invention, after determining that the current state is the driving state and the target state is the recycling state, the control module is further configured to:

[0045] Determine whether the current actual torque at the wheel end is greater than a first preset torque threshold and whether the current actual torque at the wheel end is less than a second preset torque threshold, wherein the first preset torque threshold is less than the second preset torque threshold;

[0046] If the current wheel end actual torque is greater than the first preset torque threshold and the current wheel end actual torque is less than the second preset torque threshold, then the current wheel end actual torque is determined to be in the preset negative zero-crossing interval.

[0047] According to an embodiment of the present invention, before determining whether the current actual torque at the wheel end is greater than the first preset torque threshold and whether the current actual torque at the wheel end is less than the second preset torque threshold, the control module is further configured to:

[0048] The vehicle is controlled to be in a parking state, and during the process of adjusting the torque of the motor from a first initial value to a first target value based on a first preset rate, the first actual torque when the motor speed meets the first preset fluctuation condition is obtained, and the second actual torque when the motor speed is 0 and there is no fluctuation is obtained.

[0049] The second preset torque threshold is obtained based on the sum of the first actual torque and the first reserved torque, and the first preset torque threshold is obtained based on the difference between the second actual torque and the second reserved torque.

[0050] According to one embodiment of the present invention, the control module is specifically used for:

[0051] The first motor torque change rate limit value is determined based on the motor speed change rate.

[0052] The limit value for the torque change rate of the second motor is determined based on the actual torque of the motor.

[0053] The limit value for the rate of change of the third motor torque is determined based on the difference between the torque required by the driver and the actual torque of the motor.

[0054] The first target motor torque is obtained by summing the maximum value among the first motor torque change rate limit, the second motor torque change rate limit, and the third motor torque change rate limit with the actual motor torque.

[0055] According to an embodiment of the present invention, after determining the target state and current state of the vehicle based on the current accelerator pedal opening and the current actual wheel end torque, the determination module includes:

[0056] A positive zero-crossing unit is used to obtain a second target motor torque based on the motor speed change rate, the actual motor torque, and the driver's required torque when the current wheel end actual torque is in a preset positive zero-crossing range, if the current state is the recovery state and the target state is the driving state, and the current wheel end actual torque is in the preset positive zero-crossing range, and to perform torque control on the motor based on the second target motor torque.

[0057] According to an embodiment of the present invention, after determining that the current state is the recycling state and the target state is the driving state, the positive zero-crossing unit is further configured to:

[0058] Determine whether the current actual torque at the wheel end is greater than a third preset torque threshold and whether the current actual torque at the wheel end is less than a fourth preset torque threshold, wherein the third preset torque threshold is less than the fourth preset torque threshold;

[0059] If the current wheel end actual torque is greater than the third preset torque threshold and the current wheel end actual torque is less than the fourth preset torque threshold, then the current wheel end actual torque is determined to be in the preset positive zero-crossing interval.

[0060] According to an embodiment of the present invention, before determining whether the current wheel end actual torque is greater than the third preset torque threshold and whether the current wheel end actual torque is less than the fourth preset torque threshold, the positive zero-crossing unit is further configured to:

[0061] The vehicle is controlled to be in a parking state, and during the process of adjusting the torque of the motor from a second initial value to a second target value based on a second preset rate, a third actual torque is obtained when the motor speed meets the second preset fluctuation condition, and a fourth actual torque is obtained when the motor speed is 0 and there is no fluctuation.

[0062] The third preset torque threshold is obtained based on the difference between the third actual torque and the third reserved torque, and the fourth preset torque threshold is obtained based on the sum of the fourth actual torque and the fourth reserved torque.

[0063] According to one embodiment of the present invention, the positive zero-crossing unit is specifically used for:

[0064] The limit value for the torque change rate of the fourth motor is determined based on the motor speed change rate.

[0065] The torque change rate limit value of the fifth motor is determined based on the actual torque of the motor.

[0066] The torque variation rate limit value of the sixth motor is determined based on the difference between the driver's required torque and the actual torque of the motor;

[0067] The second target motor torque is obtained by summing the minimum value among the fourth motor torque change rate limit, the fifth motor torque change rate limit, and the sixth motor torque change rate limit with the actual motor torque.

[0068] According to an embodiment of the present invention, the determining module is specifically used for:

[0069] Based on the current accelerator pedal opening, determine whether the driver's required torque is greater than or equal to a first preset value;

[0070] If the torque required by the driver is greater than or equal to the first preset value, the target state is determined to be the driving state; otherwise, the target state is determined to be the recovery state.

[0071] Determine whether the current actual torque at the wheel end is less than a second preset value;

[0072] If the actual torque at the current wheel end is less than the second preset value, then the current state is determined to be the recovery state; otherwise, the current state is determined to be the driving state.

[0073] According to the vehicle control device proposed in this embodiment, the vehicle's target state and current state are determined by acquiring the current accelerator pedal opening and the current actual wheel torque. When the current state is determined to be a driving state and the target state to be a regenerative braking state, and the current actual wheel torque is within a preset negative zero-crossing range, a first target motor torque is obtained based on the motor speed change rate, the actual motor torque, and the driver's required torque. The motor torque is then controlled based on this first target motor torque. Thus, by real-time judgment of the zero-crossing range and torque control of the motor, a balance is achieved between the power response speed and vehicle impact during acceleration and deceleration, improving the overall driving performance and smoothness of the vehicle, and enhancing the user experience.

[0074] To achieve the above objectives, a third aspect of the present invention provides a vehicle comprising: a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the program to implement the vehicle control method as described in the above embodiments.

[0075] To achieve the above objectives, a fourth aspect of the present invention provides a computer-readable storage medium having a computer program stored thereon, which is executed by a processor to implement the vehicle control method as described in the above embodiments.

[0076] Additional aspects and advantages of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0077] The above and / or additional aspects and advantages of the present invention will become apparent and readily understood from the following description of the embodiments taken in conjunction with the accompanying drawings, wherein:

[0078] Figure 1 A flowchart illustrating a vehicle control method according to an embodiment of the present invention;

[0079] Figure 2 This is a schematic diagram of a negative zero-crossing process control method according to a specific embodiment of the present invention;

[0080] Figure 3 This is a linear variation graph of the torque variation slope control method according to a specific embodiment of the present invention;

[0081] Figure 4 This is a schematic diagram of a positive zero-crossing process control method according to a specific embodiment of the present invention;

[0082] Figure 5 This is a schematic flowchart of a vehicle control method according to a specific embodiment of the present invention;

[0083] Figure 6 This is a block diagram of a vehicle control device according to an embodiment of the present invention;

[0084] Figure 7 This is a structural schematic diagram of a vehicle provided according to an embodiment of the present invention.

[0085] Among them, 10-vehicle control device; 100-acquisition module, 200-judgment module, 300-control module; 701-memory, 702-processor, 703-communication interface. Detailed Implementation

[0086] Embodiments of the present invention are described in detail below. Examples of these embodiments are illustrated in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain the present invention, and should not be construed as limiting the present invention.

[0087] A vehicle control method and apparatus according to an embodiment of the present invention will now be described with reference to the accompanying drawings. First, the vehicle control method according to an embodiment of the present invention will be described with reference to the accompanying drawings.

[0088] Figure 1 This is a flowchart of a vehicle control method provided in one embodiment of the present invention.

[0089] like Figure 1 As shown, the vehicle control method includes the following steps:

[0090] In step S101, the current accelerator pedal opening and the current actual wheel end torque of the vehicle are obtained.

[0091] Among them, the accelerator pedal opening is the opening and closing angle of the accelerator pedal after the driver applies force to it.

[0092] Specifically, in this embodiment of the invention, the accelerator pedal opening and the current actual wheel torque can be obtained through the vehicle's ECU (Electronic Control Unit). When the driver presses the accelerator pedal, the vehicle's acceleration system detects the accelerator pedal opening through sensors and transmits the signal to the vehicle's ECU; at the same time, during vehicle operation, the ECU can also obtain the current actual wheel torque based on the wheel rotation rate.

[0093] In step S102, the target state and current state of the vehicle are determined based on the current accelerator pedal opening and the current actual wheel end torque.

[0094] Understandably, during driving, the driver will assess the current driving conditions, the surrounding environment, and the vehicle's current driving status, applying different forces to the accelerator pedal. The intentions of slow acceleration / deceleration, normal acceleration / deceleration, and emergency acceleration / deceleration are reflected in the magnitude of the changes in the acceleration / deceleration pedal. When the driver intends to change gears slowly, the accelerator pedal opening is smaller; when the driver intends to change gears abruptly, the accelerator pedal opening is larger.

[0095] Optionally, in some embodiments, determining the target state and current state of the vehicle based on the current accelerator pedal opening and the current actual wheel torque includes: determining whether the driver's required torque is greater than or equal to a first preset value based on the current accelerator pedal opening; if the driver's required torque is greater than or equal to the first preset value, then determining the target state as a driving state, otherwise determining the target state as a regenerative braking state; determining whether the current actual wheel torque is less than a second preset value; if the current actual wheel torque is less than the second preset value, then determining the current state as a regenerative braking state, otherwise determining the current state as a driving state.

[0096] The first preset value and the second preset value can be torque limit data set by those skilled in the art according to actual needs, or data obtained through a limited number of computer simulations, and are not specifically limited here.

[0097] Specifically, the vehicle's target state is a new driving state achieved by the driver after acceleration or deceleration. One way to accelerate a vehicle is for the driver to apply force to the accelerator pedal, opening and closing it at a certain angle. Therefore, the driver's required torque can be obtained from the accelerator pedal opening, and the magnitude of the required torque can be used to determine the vehicle's target state. The vehicle's current state is determined by the current wheel-end torque.

[0098] For example, in one embodiment of the present invention, both the first preset value and the second preset value are zero. When the required torque is greater than or equal to zero, the target state is the driving state; when the required torque is less than zero, the target state is the regeneration state. When the actual torque at the wheel end is greater than zero, the current state is the driving state; when the actual torque is less than zero, the current state is the regeneration state.

[0099] In step S103, if the current state is driving state and the target state is recovery state, then when the actual torque at the current wheel end is in the preset negative zero-crossing range, the first target motor torque is obtained according to the motor speed change rate, the actual motor torque and the driver's required torque, and the motor torque is controlled according to the first target motor torque.

[0100] In some embodiments, obtaining a first target motor torque based on the motor speed change rate, the actual motor torque, and the driver's required torque includes: determining a first motor torque change rate limit value based on the motor speed change rate; determining a second motor torque change rate limit value based on the actual motor torque; determining a third motor torque change rate limit value based on the difference between the driver's required torque and the actual motor torque; and obtaining the first target motor torque by summing the maximum value among the first, second, and third motor torque change rate limit values ​​with the actual motor torque.

[0101] Specifically, such as Figure 2 As shown, Figure 2This is a schematic diagram of a negative zero-crossing process control method according to a specific embodiment of the present invention. First, the change in motor speed per unit time is divided by the unit time to calculate the motor speed change rate. The calculated motor speed change rate is then filtered to avoid fluctuations. A first motor torque change rate limit is determined based on the filtered motor speed change rate. A second motor torque change rate limit is determined based on the received actual motor torque. A third motor torque change rate limit is obtained by subtracting the actual motor torque from the driver's required torque. Since the torque at negative zero crossing changes from positive to negative, and the torque change rate is negative, the largest value among the change rate limits is selected (i.e., the slowest torque slope change). The maximum value is added to the actual motor torque to obtain the first target motor torque. Figure 3 As shown, the characteristic of this control method is that it uses the motor speed change rate to control the motor torque change rate. Its advantage is that the motor speed change rate can quickly identify when the transmission system has entered the transmission direction switching stage, thereby controlling the torque change slope in advance.

[0102] Therefore, by setting two limiting thresholds, when the current wheel-end torque falls within the range of the limiting thresholds, the vehicle is determined to be in the negative zero-crossing range. The torque change slope is controlled according to the negative zero-crossing state, thereby reducing the torque change rate and thus reducing the vibration generated when the vehicle torque crosses zero, and mitigating the impact of the zero-crossing state on the vehicle.

[0103] To help those skilled in the art further understand how to determine if the actual torque at the wheel end is in a preset negative zero-crossing range, a detailed explanation is provided below with reference to specific embodiments.

[0104] As one possible implementation, in some embodiments, after determining that the current state is the driving state and the target state is the recycling state, the method further includes: determining whether the current actual torque at the wheel end is greater than a first preset torque threshold and whether the current actual torque at the wheel end is less than a second preset torque threshold, wherein the first preset torque threshold is less than the second preset torque threshold; if the current actual torque at the wheel end is greater than the first preset torque threshold and the current actual torque at the wheel end is less than the second preset torque threshold, then the current actual torque at the wheel end is determined to be in a preset negative zero-crossing interval.

[0105] It is understandable that when the actual torque at the wheel end changes from the driving state to the regenerative state, it means that the power transmission process changes from the motor driving the vehicle to the vehicle reversing the motor. Due to the differences between different vehicle models and structures, the actual torque at the wheel end will have an error during this conversion process. In order to eliminate this error, this embodiment of the invention sets a first preset torque threshold and a second preset torque threshold. When the actual torque at the wheel end falls within the threshold range of the first preset torque threshold and the second preset torque threshold, it means that the current actual torque at the wheel end is within the preset negative zero-crossing interval.

[0106] In some embodiments, before determining whether the current wheel-end actual torque is greater than the first preset torque threshold and whether the current wheel-end actual torque is less than the second preset torque threshold, the method further includes: controlling the vehicle to be in a parked state, and during the process of controlling the motor torque to adjust from a first initial value to a first target value based on a first preset rate, obtaining a first actual torque when the motor speed meets a first preset fluctuation condition, and obtaining a second actual torque when the motor speed is 0 and there is no fluctuation; obtaining the second preset torque threshold based on the sum of the first actual torque and the first reserved torque, and obtaining the first preset torque threshold based on the difference between the second actual torque and the second reserved torque.

[0107] It is understandable that when the actual torque at the wheel end changes from the driving state to the regenerative state, the motor speed will fluctuate due to the presence of transmission system clearance and damping. This invention can utilize the fluctuation of motor speed to determine the torque threshold used to define the zero-crossing interval. Since the motor speed fluctuation can only be clearly observed when the rate of change of motor torque is low, this invention employs a method of slowly changing the motor torque. The current motor torque is recorded when the motor first fluctuates and when the fluctuation approaches zero. The sum and difference values ​​of the motor torque at these two moments are then calculated with the original reserved torque to obtain the corrected preset torque threshold.

[0108] Specifically, when the vehicle is parked, this embodiment of the invention allows manual control of the drive motor torque to change from an initial set value (a positive value, e.g., 50 Nm) to a target set value (a negative value, e.g., -50 Nm) at a very small rate (e.g., -0.1 Nm / s). During this process, the motor speed will fluctuate due to transmission system clearances and damping. When the motor speed first fluctuates, the actual motor torque plus a first reserved torque equals a second preset torque threshold. When the motor speed is completely stationary without fluctuation, the actual motor torque minus the second reserved torque equals the first preset torque threshold. Therefore, when the actual torque at the current wheel end is greater than the first preset torque threshold and less than the second preset torque threshold, the actual torque at the current wheel end is within a preset negative zero-crossing range.

[0109] Furthermore, the methods for determining and controlling the positive zero-crossing state of the vehicle will be described in detail in the embodiments of this application below.

[0110] Optionally, in some embodiments, after determining the target state and current state of the vehicle based on the current accelerator pedal opening and the current actual wheel torque, the method further includes: if the current state is a regenerative braking state and the target state is a driving state, then when the current actual wheel torque is in a preset positive zero-crossing range, a second target motor torque is obtained based on the motor speed change rate, the actual motor torque, and the driver's required torque, and torque control of the motor is performed based on the second target motor torque.

[0111] Specifically, when the actual torque at the wheel end changes from the recovery state to the driving state, it signifies a shift in power transmission from the vehicle's reversing motor to the motor-driven vehicle. At this point, the vehicle is in the positive zero-crossing range. Due to transmission system clearances and damping, the motor speed will fluctuate. To reduce vibration between components during the zero-crossing range, torque control of the motor is necessary. This invention obtains a second target motor torque based on the motor speed change rate, the actual motor torque, and the driver's required torque, thereby enabling torque control of the motor.

[0112] In some embodiments, obtaining a second target motor torque based on the motor speed change rate, the actual motor torque, and the driver's required torque includes: determining a fourth motor torque change rate limit value based on the motor speed change rate; determining a fifth motor torque change rate limit value based on the actual motor torque; determining a sixth motor torque change rate limit value based on the difference between the driver's required torque and the actual motor torque; and obtaining the second target motor torque by summing the minimum of the fourth, fifth, and sixth motor torque change rate limit values ​​with the actual motor torque.

[0113] Specifically, such as Figure 4 As shown, Figure 4 This is a schematic diagram of a positive zero-crossing process control method according to a specific embodiment of the present invention. First, the change in motor speed per unit time is divided by the unit time to calculate the motor speed change rate. The calculated motor speed change rate is filtered to avoid fluctuations in the motor speed change rate. A fourth motor torque change rate limit value is determined based on the filtered motor speed change rate. A fifth motor torque change rate limit value is determined based on the received actual motor torque. A sixth motor torque change rate limit value is obtained by subtracting the actual motor torque from the torque required by the driver. Since the torque for positive zero crossing changes from negative to positive, and the torque change rate is positive, the smallest value among the change rate limit values ​​is selected (i.e., the slowest torque slope change is selected). The minimum value is added to the actual motor torque to obtain the second target motor torque.

[0114] Furthermore, in some embodiments, after determining that the current state is a recovery state and the target state is a driving state, the method further includes: determining whether the current actual torque at the wheel end is greater than a third preset torque threshold and whether the current actual torque at the wheel end is less than a fourth preset torque threshold, wherein the third preset torque threshold is less than the fourth preset torque threshold; if the current actual torque at the wheel end is greater than the third preset torque threshold and the current actual torque at the wheel end is less than the fourth preset torque threshold, then the current actual torque at the wheel end is determined to be in a preset positive zero-crossing interval.

[0115] It is understandable that when the actual torque at the wheel end changes from the regenerative braking state to the driving state, it signifies a shift in power transmission from the vehicle's reversing motor to a motor-driven vehicle. Differences in vehicle models and construction can lead to errors in the actual torque at the wheel end during this transition. To eliminate this error, this embodiment of the invention sets a third preset torque threshold and a fourth preset torque threshold, where the third preset torque threshold is less than the fourth preset torque threshold. When the actual torque at the wheel end falls within the threshold range of the third and fourth preset torque thresholds, it means that the current actual torque at the wheel end is within a preset positive zero-crossing interval.

[0116] In some embodiments, before determining whether the current wheel-end actual torque is greater than the third preset torque threshold and whether the current wheel-end actual torque is less than the fourth preset torque threshold, the method further includes: controlling the vehicle to be in a parked state, and during the process of controlling the motor torque to adjust from a second initial value to a second target value based on a second preset rate, obtaining the third actual torque when the motor speed meets the second preset fluctuation condition, and obtaining the fourth actual torque when the motor speed is 0 and there is no fluctuation; obtaining the third preset torque threshold based on the difference between the third actual torque and the third reserved torque, and obtaining the fourth preset torque threshold based on the sum of the fourth actual torque and the fourth reserved torque.

[0117] Specifically, when the vehicle in this embodiment of the invention is in a parked state, the torque of the drive motor can be controlled to change from an initial set value (which is negative, for example, -50 Nm) to a target set value (which is positive, for example, 50 Nm) at a very small rate (for example, 0.1 Nm / s). During this process, due to the presence of transmission system clearance and damping, the motor speed will fluctuate. When the motor speed first fluctuates, the actual motor torque at this time minus the third reserved torque is the third preset torque threshold; when the motor speed is completely stationary without fluctuation, the actual motor torque at this time plus the fourth reserved torque is the fourth preset torque threshold. Thus, when the actual torque at the current wheel end is greater than the third preset torque threshold and less than the fourth preset torque threshold, the actual torque at the current wheel end is in the preset positive zero-crossing range.

[0118] To enable those skilled in the art to further understand the vehicle control method of the embodiments of this application, a detailed description is provided below with reference to specific embodiments.

[0119] Specifically, such as Figure 5 As shown, the vehicle control method includes the following steps:

[0120] S501, Driver's Intent Judgment.

[0121] The required torque is determined based on the driver's operation of the accelerator pedal opening.

[0122] S502, the current state is driving and the target state is recycling. If so, execute S503; otherwise, execute S505.

[0123] The current state is determined by the actual torque at the wheel end. When the actual torque is greater than or equal to zero, it is in driving mode; when the actual torque is less than zero, it is in regenerative braking mode. The target state is determined by the torque demanded by the driver. When the demanded torque is greater than or equal to zero, it is in driving mode; when the demanded torque is less than zero, it is in regenerative braking mode.

[0124] S503, negative zero-crossing interval judgment.

[0125] When the actual torque at the wheel end changes from the driving state to the regenerative braking state, the power transmission process changes from the motor driving the vehicle to the vehicle reversing and towing the motor. When the actual torque at the wheel end is less than a first preset torque threshold but greater than a second preset torque threshold, it is determined that the vehicle has entered the negative zero-crossing range.

[0126] S504, negative zero-crossing process control, returns to S501 after completion.

[0127] The torque change process when entering the negative zero-crossing range is controlled. After the control is completed, return to S501 and wait for the next zero-crossing range judgment.

[0128] S505, the current state is recycling and the target state is driving. If so, execute S506; otherwise, execute S508.

[0129] S506, positive zero-crossing interval judgment.

[0130] When the actual torque at the wheel end changes from the regenerative braking state to the driving state, the power transmission process changes from the vehicle's reversing motor to the motor driving the vehicle. When the actual torque at the wheel end is greater than the third preset torque threshold but less than the fourth preset torque threshold, it is determined that the vehicle has entered the positive zero-crossing range.

[0131] S507, positive zero-crossing process control, returns to S501 after completion.

[0132] The torque change process during the positive zero-crossing interval is controlled, and after the control is completed, it returns to S501 to wait for the next zero-crossing interval judgment.

[0133] S508, End.

[0134] According to the vehicle control method proposed in this embodiment, the current accelerator pedal opening and the current actual wheel torque are obtained, and the target state and current state of the vehicle are determined based on these parameters. When the current state is determined to be a driving state and the target state to be a regenerative braking state, and the current actual wheel torque is within a preset negative zero-crossing range, a first target motor torque is obtained based on the motor speed change rate, the actual motor torque, and the driver's required torque. The motor torque is then controlled based on this first target motor torque. Therefore, by real-time judgment of the zero-crossing range and torque control of the motor, a balance between the power response speed and vehicle impact during acceleration and deceleration is achieved, improving the overall driving performance and smoothness of the vehicle, and enhancing the user experience.

[0135] Next, the vehicle control device according to an embodiment of the present invention is described with reference to the accompanying drawings.

[0136] Figure 6 This is a block diagram of a vehicle control device according to an embodiment of the present invention.

[0137] like Figure 6 As shown, the vehicle control device 10 includes: an acquisition module 100, a judgment module 200, and a control module 300.

[0138] The acquisition module 100 is used to acquire the current accelerator pedal opening and the current actual wheel end torque of the vehicle.

[0139] The judgment module 200 is used to determine the target state and current state of the vehicle based on the current accelerator pedal opening and the current actual wheel end torque.

[0140] The control module 300 is used to obtain a first target motor torque based on the motor speed change rate, the actual motor torque, and the driver's required torque when the actual torque at the current wheel end is in a preset negative zero-crossing range, if the current state is driving state and the target state is recovery state, and the current state is driving state. Then, the control module 300 controls the motor torque based on the first target motor torque.

[0141] According to an embodiment of the present invention, after determining that the current state is a driving state and the target state is a recycling state, the control module 300 is further configured to:

[0142] Determine whether the current actual torque at the wheel end is greater than a first preset torque threshold and whether the current actual torque at the wheel end is less than a second preset torque threshold, wherein the first preset torque threshold is less than the second preset torque threshold;

[0143] If the current actual torque at the wheel end is greater than the first preset torque threshold and less than the second preset torque threshold, then the current actual torque at the wheel end is determined to be in the preset negative zero-crossing range.

[0144] According to an embodiment of the present invention, before determining whether the actual torque at the current wheel end is greater than a first preset torque threshold and whether the actual torque at the current wheel end is less than a second preset torque threshold, the control module 300 is further configured to:

[0145] The vehicle is controlled to be in a parked state, and during the process of adjusting the motor torque from a first initial value to a first target value based on a first preset rate, the first actual torque when the motor speed meets the first preset fluctuation condition is obtained, and the second actual torque when the motor speed is 0 and there is no fluctuation is obtained.

[0146] The second preset torque threshold is obtained based on the sum of the first actual torque and the first reserved torque, and the first preset torque threshold is obtained based on the difference between the second actual torque and the second reserved torque.

[0147] According to one embodiment of the present invention, the control module 300 is specifically used for:

[0148] The first motor torque change rate limit value is determined based on the motor speed change rate.

[0149] The limit value for the rate of change of torque of the second motor is determined based on the actual torque of the motor.

[0150] The limit value for the torque change rate of the third motor is determined based on the difference between the torque demanded by the driver and the actual torque of the motor.

[0151] The first target motor torque is obtained by summing the maximum value among the first motor torque change rate limit, the second motor torque change rate limit, and the third motor torque change rate limit with the actual motor torque.

[0152] According to one embodiment of the present invention, after determining the target state and current state of the vehicle based on the current accelerator pedal opening and the current actual wheel end torque, the determination module 200 includes:

[0153] The positive zero-crossing unit is used to obtain the second target motor torque based on the motor speed change rate, the actual motor torque, and the driver's required torque when the current state is the recovery state and the target state is the driving state, and the current actual torque at the wheel end is in the preset positive zero-crossing range. Then, the unit performs torque control on the motor based on the second target motor torque.

[0154] According to an embodiment of the present invention, after determining that the current state is a recycling state and the target state is a driving state, the positive zero-crossing unit is further configured to:

[0155] Determine whether the current actual torque at the wheel end is greater than the third preset torque threshold and less than the fourth preset torque threshold, wherein the third preset torque threshold is less than the fourth preset torque threshold;

[0156] If the current actual torque at the wheel end is greater than the third preset torque threshold and less than the fourth preset torque threshold, then the current actual torque at the wheel end is determined to be in the preset positive zero-crossing range.

[0157] According to one embodiment of the present invention, before determining whether the current actual torque at the wheel end is greater than a third preset torque threshold and whether the current actual torque at the wheel end is less than a fourth preset torque threshold, the positive zero-crossing unit is further configured to:

[0158] The vehicle is controlled to be in a parked state, and during the process of adjusting the motor torque from a second initial value to a second target value based on a second preset rate, a third actual torque is obtained when the motor speed meets the second preset fluctuation condition, and a fourth actual torque is obtained when the motor speed is 0 and there is no fluctuation.

[0159] The third preset torque threshold is obtained based on the difference between the third actual torque and the third reserved torque, and the fourth preset torque threshold is obtained based on the sum of the fourth actual torque and the fourth reserved torque.

[0160] According to one embodiment of the present invention, the positive zero-crossing unit is specifically used for:

[0161] The limit value for the torque change rate of the fourth motor is determined based on the motor speed change rate.

[0162] The torque change rate limit value of the fifth motor is determined based on the actual torque of the motor.

[0163] The torque variation rate limit of the sixth motor is determined based on the difference between the driver's required torque and the actual torque of the motor.

[0164] The second target motor torque is obtained by summing the minimum value among the fourth, fifth, and sixth motor torque change rate limits with the actual motor torque.

[0165] According to one embodiment of the present invention, the determination module 200 is specifically used for:

[0166] Determine whether the driver's required torque is greater than or equal to the first preset value based on the current accelerator pedal opening.

[0167] If the torque required by the driver is greater than or equal to the first preset value, the target state is determined to be the driving state; otherwise, the target state is determined to be the regeneration state.

[0168] Determine whether the current actual torque at the wheel end is less than the second preset value;

[0169] If the actual torque at the wheel end is less than the second preset value, the current state is determined to be the recovery state; otherwise, the current state is determined to be the driving state.

[0170] According to the vehicle control device proposed in this embodiment, the vehicle's target state and current state are determined by acquiring the current accelerator pedal opening and the current actual wheel torque. When the current state is determined to be a driving state and the target state to be a regenerative braking state, and the current actual wheel torque is within a preset negative zero-crossing range, a first target motor torque is obtained based on the motor speed change rate, the actual motor torque, and the driver's required torque. The motor torque is then controlled based on this first target motor torque. Thus, by real-time judgment of the zero-crossing range and torque control of the motor, a balance is achieved between the power response speed and vehicle impact during acceleration and deceleration, improving the overall driving performance and smoothness of the vehicle, and enhancing the user experience.

[0171] Figure 7 This is a schematic diagram of a vehicle provided in an embodiment of the present invention. The vehicle may include:

[0172] The memory 701, the processor 702, and the computer program stored on the memory 701 and executable on the processor 702.

[0173] When the processor 702 executes the program, it implements the vehicle control method provided in the above embodiments.

[0174] Furthermore, the vehicle also includes:

[0175] Communication interface 703 is used for communication between memory 701 and processor 702.

[0176] The memory 701 is used to store computer programs that can run on the processor 702.

[0177] The memory 701 may include high-speed RAM (Random Access Memory) memory, and may also include non-volatile memory, such as at least one disk storage.

[0178] If the memory 701, processor 702, and communication interface 703 are implemented independently, then the communication interface 703, memory 701, and processor 702 can be interconnected via a bus to complete communication between them. The bus can be an ISA (Industry Standard Architecture) bus, a PCI (Peripheral Component Interconnect) bus, or an EISA (Extended Industry Standard Architecture) bus, etc. The bus can be divided into address bus, data bus, control bus, etc. For ease of representation, Figure 7 The bus is represented by a single thick line, but this does not mean that there is only one bus or one type of bus.

[0179] Optionally, in a specific implementation, if the memory 701, processor 702, and communication interface 703 are integrated on a single chip, then the memory 701, processor 702, and communication interface 703 can communicate with each other through an internal interface.

[0180] The processor 702 may be a CPU (Central Processing Unit), an ASIC (Application Specific Integrated Circuit), or one or more integrated circuits configured to implement embodiments of the present invention.

[0181] This invention also provides a computer-readable storage medium storing a computer program thereon, which, when executed by a processor, implements the vehicle control method described above.

[0182] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0183] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0184] Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of the present invention.

Claims

1. A method for controlling a vehicle, characterized in that, Includes the following steps: Obtain the vehicle's current accelerator pedal opening and current wheel-end torque; The target state and current state of the vehicle are determined based on the current accelerator pedal opening and the current actual wheel end torque. If the current state is the driving state and the target state is the recovery state, then when the actual torque at the current wheel end is in the preset negative zero-crossing range, the first target motor torque is obtained according to the motor speed change rate, the actual motor torque and the driver's required torque, and the motor torque is controlled according to the first target motor torque. The process of obtaining the first target motor torque based on the motor speed change rate, the actual motor torque, and the driver's required torque includes: The first motor torque change rate limit value is determined based on the motor speed change rate. The limit value for the torque change rate of the second motor is determined based on the actual torque of the motor. The limit value for the rate of change of the third motor torque is determined based on the difference between the torque required by the driver and the actual torque of the motor. The first target motor torque is obtained by summing the maximum value among the first motor torque change rate limit, the second motor torque change rate limit, and the third motor torque change rate limit with the actual motor torque. Determining the target state and current state of the vehicle based on the current accelerator pedal opening and the current actual wheel torque includes: Based on the current accelerator pedal opening, determine whether the driver's required torque is greater than or equal to a first preset value; If the torque required by the driver is greater than or equal to the first preset value, the target state is determined to be the driving state; otherwise, the target state is determined to be the recovery state. Determine whether the current actual torque at the wheel end is less than a second preset value; If the actual torque at the current wheel end is less than the second preset value, then the current state is determined to be the recovery state; otherwise, the current state is determined to be the driving state.

2. The method according to claim 1, characterized in that, After determining that the current state is the driving state and the target state is the recycling state, the method further includes: Determine whether the current actual torque at the wheel end is greater than a first preset torque threshold and whether the current actual torque at the wheel end is less than a second preset torque threshold, wherein the first preset torque threshold is less than the second preset torque threshold; If the current wheel end actual torque is greater than the first preset torque threshold and the current wheel end actual torque is less than the second preset torque threshold, then the current wheel end actual torque is determined to be in the preset negative zero-crossing interval.

3. The method according to claim 2, characterized in that, Before determining whether the current wheel-end actual torque is greater than the first preset torque threshold and whether the current wheel-end actual torque is less than the second preset torque threshold, the method further includes: The vehicle is controlled to be in a parking state, and during the process of adjusting the torque of the motor from a first initial value to a first target value based on a first preset rate, the first actual torque when the motor speed meets the first preset fluctuation condition is obtained, and the second actual torque when the motor speed is 0 and there is no fluctuation is obtained. The second preset torque threshold is obtained based on the sum of the first actual torque and the first reserved torque, and the first preset torque threshold is obtained based on the difference between the second actual torque and the second reserved torque.

4. The method according to claim 1, characterized in that, After determining the target state and current state of the vehicle based on the current accelerator pedal opening and the current actual wheel-end torque, the process further includes: If the current state is the recovery state and the target state is the driving state, then when the actual torque at the current wheel end is in the preset positive zero-crossing range, the second target motor torque is obtained according to the motor speed change rate, the actual motor torque and the driver's required torque, and the motor is torque controlled according to the second target motor torque.

5. The method according to claim 4, characterized in that, After determining that the current state is the recycling state and the target state is the driving state, the method further includes: Determine whether the current actual torque at the wheel end is greater than a third preset torque threshold and whether the current actual torque at the wheel end is less than a fourth preset torque threshold, wherein the third preset torque threshold is less than the fourth preset torque threshold; If the current wheel end actual torque is greater than the third preset torque threshold and the current wheel end actual torque is less than the fourth preset torque threshold, then the current wheel end actual torque is determined to be in the preset positive zero-crossing interval.

6. The method according to claim 5, characterized in that, Before determining whether the current wheel-end actual torque is greater than the third preset torque threshold and whether the current wheel-end actual torque is less than the fourth preset torque threshold, the method further includes: The vehicle is controlled to be in a parking state, and during the process of adjusting the torque of the motor from a second initial value to a second target value based on a second preset rate, a third actual torque is obtained when the motor speed meets the second preset fluctuation condition, and a fourth actual torque is obtained when the motor speed is 0 and there is no fluctuation. The third preset torque threshold is obtained based on the difference between the third actual torque and the third reserved torque, and the fourth preset torque threshold is obtained based on the sum of the fourth actual torque and the fourth reserved torque.

7. The method according to claim 4 or 5, characterized in that, The process of obtaining the second target motor torque based on the motor speed change rate, the actual motor torque, and the driver's required torque includes: The limit value for the torque change rate of the fourth motor is determined based on the motor speed change rate. The torque change rate limit value of the fifth motor is determined based on the actual torque of the motor. The torque variation rate limit value of the sixth motor is determined based on the difference between the driver's required torque and the actual torque of the motor; The second target motor torque is obtained by summing the minimum value among the fourth motor torque change rate limit, the fifth motor torque change rate limit, and the sixth motor torque change rate limit with the actual motor torque.

8. A vehicle control device, suitable for control using the vehicle control method according to any one of claims 1-7, characterized in that, include: The acquisition module is used to acquire the vehicle's current accelerator pedal opening and the current actual wheel torque; The judgment module is used to determine the target state and current state of the vehicle based on the current accelerator pedal opening and the current actual wheel end torque; The control module is configured to, if the current state is a driving state and the target state is a recovery state, obtain a first target motor torque based on the motor speed change rate, the actual motor torque, and the driver's required torque when the actual torque at the current wheel end is in a preset negative zero-crossing range, and then perform torque control on the motor based on the first target motor torque.

Images