Vehicle control methods, devices and vehicles

Abstract

This disclosure relates to a vehicle control method, apparatus, and vehicle. The method includes: if the vehicle enters an emergency braking state, determining a target braking torque for the vehicle wheels; maintaining a constant current hydraulic torque, and determining a target regenerative braking torque for the wheel motors based on the current hydraulic torque and the target braking torque for the vehicle wheels; and controlling the vehicle's wheel motors to brake according to the determined target regenerative braking torque. In this way, when the vehicle enters an emergency braking state, maintaining a constant current hydraulic torque and utilizing the faster-responding braking torque of the wheel motors to meet the vehicle's braking needs shortens the braking time, improves energy recovery efficiency, and enhances safety.

Description

Technical Field

[0001] This disclosure relates to the field of vehicles, and more specifically, to a vehicle control method, apparatus, and vehicle. Background Technology

[0002] With the continuous advancement of technology, new energy vehicles are developing rapidly. New energy vehicles feature energy recovery systems (electric braking), which convert the kinetic energy of vehicle deceleration into electrical energy to increase the vehicle's range. Braking methods for new energy vehicles include electric braking and hydraulic braking. If the wheels lock up during emergency braking of a new energy vehicle, the vehicle is at high risk. Summary of the Invention

[0003] The purpose of this disclosure is to provide a vehicle control method, apparatus, and vehicle that can fully utilize the braking torque of the wheel motors to meet braking requirements and shorten braking time when the vehicle enters an emergency braking state.

[0004] To achieve the above objectives, this disclosure provides a vehicle control method, the method comprising:

[0005] If the vehicle enters an emergency braking state, determine the target braking torque of the vehicle wheels;

[0006] Keeping the current hydraulic torque constant, and determining the target regenerative braking torque of the wheel motor based on the current hydraulic torque and the target braking torque of the vehicle wheels;

[0007] The vehicle's wheel motors are controlled to brake according to a predetermined target recovery braking torque.

[0008] Optionally, determining the target regenerative braking torque of the wheel motor based on the current hydraulic torque and the target braking torque of the vehicle wheels includes:

[0009] The difference between the target braking torque of the vehicle wheel and the current hydraulic torque is determined as the target regenerative braking torque of the wheel motor.

[0010] Optionally, after the step of controlling the wheel motors of the vehicle to brake according to the determined target regenerative braking torque, the method further includes:

[0011] If the vehicle wheels lock up, the target regenerative braking torque of the wheel motor is reduced.

[0012] Optionally, after the step of reducing the target regenerative braking torque of the vehicle motor, the method further includes:

[0013] If the target regenerative braking torque of the wheel motor is less than the torque threshold and the vehicle wheels are still locked, the hydraulic braking torque of the vehicle wheels is reduced until the vehicle wheels are no longer locked. Then, the reduction of the hydraulic braking torque of the vehicle wheels is stopped, and the hydraulic braking torque of the vehicle wheels is kept constant. The difference between the target braking torque of the vehicle wheels and the reduced hydraulic braking torque is determined as the target regenerative braking torque of the wheel motor.

[0014] Optionally, determining the target braking torque for the vehicle wheels includes:

[0015] The target braking torque of the vehicle wheels is determined based on the driver's required braking torque, wherein the sum of the target braking torques of the vehicle wheels is less than the driver's required braking torque.

[0016] Optionally, the method further includes:

[0017] Determine the maximum available regenerative braking torque of the wheel motor;

[0018] If the vehicle enters a normal braking state, the target regenerative braking torque of the wheel motor is determined based on the maximum available regenerative braking torque of the wheel motor and the target braking torque of the vehicle wheels;

[0019] The hydraulic target braking torque is determined based on the target regenerative braking torque of the wheel motor.

[0020] Optionally, determining the maximum available regenerative braking torque of the wheel motor includes:

[0021] Determine the driver's required braking torque;

[0022] The pre-distributed braking torque of the wheel motor is determined based on the vehicle speed and the driver's required braking torque.

[0023] The maximum available regenerative braking torque of the wheel motor is determined based on the pre-distributed braking torque of the wheel motor, the maximum charging power of the vehicle battery, and the maximum regenerative braking power of the vehicle's wheel motor.

[0024] Optionally, determining the pre-distributed braking torque of the wheel motor based on the vehicle speed and the driver's required braking torque includes:

[0025] The ratio of the pre-distributed braking torque of the wheel motor to the braking torque required by the driver is determined based on the vehicle speed.

[0026] The pre-distributed braking torque of the wheel motor is determined based on the ratio.

[0027] Optionally, determining the maximum available regenerative braking torque of the wheel motor based on the pre-distributed braking torque of the wheel motor, the maximum charging power of the vehicle battery, and the maximum regenerative braking power of the vehicle's wheel motor includes:

[0028] The maximum regenerative braking torque of the vehicle is determined based on the maximum charging power of the vehicle battery.

[0029] The maximum regenerative braking torque of the wheel motor is determined based on the maximum regenerative power of the wheel motor.

[0030] The minimum value among the pre-distributed braking torque of the vehicle's wheel motor, the vehicle's maximum regenerative braking torque, and the maximum regenerative braking torque of the wheel motor, and the predetermined limiting torque value, is determined as the maximum available regenerative braking torque of the wheel motor.

[0031] Optionally, determining the target regenerative braking torque of the wheel motor based on the maximum available regenerative braking torque of the wheel motor and the target braking torque of the vehicle wheels includes:

[0032] If the maximum available regenerative braking torque of the wheel motor is greater than the target braking torque of the vehicle wheel, then the target braking torque of the vehicle wheel is determined as the target regenerative braking torque of the wheel motor.

[0033] If the maximum available regenerative braking torque of the wheel motor is less than or equal to the target braking torque of the vehicle wheel, then the maximum available regenerative braking torque of the wheel motor is determined as the target regenerative braking torque of the wheel motor.

[0034] This disclosure also provides a vehicle control device, including:

[0035] A memory on which computer programs are stored;

[0036] A processor is configured to execute the computer program in the memory to implement the steps of the vehicle control method described above.

[0037] This disclosure also provides a vehicle including the vehicle control device described above.

[0038] Through the above technical solution, if the vehicle enters an emergency braking state, the target braking torque of the vehicle wheels is determined, the current hydraulic torque is kept constant, and based on the current hydraulic torque and the target braking torque of the vehicle wheels, the target regenerative braking torque of the wheel motors is determined. The wheel motors are then controlled to brake according to the determined target regenerative braking torque. In this way, when the vehicle enters an emergency braking state, the current hydraulic torque is kept constant, and the braking torque of the wheel motors with faster response speed is used to meet the vehicle's braking needs, shortening the braking time, improving energy recovery efficiency, and enhancing safety.

[0039] Other features and advantages of this disclosure will be described in detail in the following detailed description section. Attached Figure Description

[0040] The accompanying drawings are provided to further illustrate the present disclosure and form part of the specification. They are used together with the following detailed description to explain the present disclosure, but do not constitute a limitation thereof. In the drawings:

[0041] Figure 1 This is a flowchart of a vehicle control method provided in an exemplary embodiment.

[0042] Figure 2 This is a schematic diagram illustrating the correspondence between vehicle speed and the pre-allocated braking torque ratio of the wheel motors, provided in an exemplary embodiment.

[0043] Figure 3 This is a schematic diagram illustrating the correspondence between time, speed, and braking torque provided in an exemplary embodiment.

[0044] Figure 4 This is a schematic diagram illustrating the correspondence between time, speed, and braking torque, provided in yet another exemplary embodiment.

[0045] Figure 5 This is a block diagram of a vehicle control device provided in an exemplary embodiment. Detailed Implementation

[0046] The specific embodiments of this disclosure will be described in detail below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are for illustration and explanation only and are not intended to limit this disclosure.

[0047] The method disclosed herein can be applied to four-motor vehicles, where each wheel of the four-motor vehicle is equipped with a motor. Figure 1 This is a flowchart of a vehicle control method provided in an exemplary embodiment. For example... Figure 1 As shown, the method includes the following steps.

[0048] In step S101, if the vehicle enters an emergency braking state, the target braking torque of the vehicle wheels is determined.

[0049] In step S102, the current hydraulic torque is kept constant, and the target recovery braking torque of the wheel motor is determined based on the current hydraulic torque and the target braking torque of the vehicle wheels.

[0050] In step S103, the vehicle's wheel motors are controlled to brake according to the determined target recovery braking torque.

[0051] When a vehicle enters an emergency braking state, its anti-lock braking system (ABS) is activated. In related technologies, when a vehicle enters an emergency braking state, the regenerative braking torque of the wheel motors is typically reduced to zero, and anti-lock control is achieved solely through the hydraulic braking torque of the vehicle wheels. However, the response speed of hydraulic braking torque is slow, resulting in a longer braking time and insufficient utilization of the wheel motor braking torque for energy recovery.

[0052] The target braking torque for the vehicle wheels is the braking torque currently required by the wheels. The target regenerative braking torque for the wheel motors is the braking torque provided by the wheel motors and applied to the vehicle wheels. The target regenerative braking torque for the wheel motors is related to the current hydraulic torque of the wheels and the target braking torque of the wheels.

[0053] When a vehicle enters an emergency braking state, the vehicle's wheels may lock up, requiring anti-lock braking control. First, the target braking torque of the vehicle's wheels can be determined while keeping the current hydraulic torque constant. Second, the target regenerative braking torque of the wheel motor can be determined based on the current hydraulic torque of the wheels and the target braking torque of the wheels.

[0054] After determining the target regenerative braking torque for the wheel motors, the vehicle's wheel motors are controlled to perform anti-lock braking according to the determined target regenerative braking torque. For example, the current hydraulic torque of the wheels can be obtained through sensors installed in the vehicle.

[0055] With the above technical solution, if the vehicle enters an emergency braking state, the target braking torque of the vehicle wheels is determined, the current hydraulic torque is kept constant, and the target recovery braking torque of the wheel motor is determined based on the current hydraulic torque and the target braking torque of the vehicle wheels, and the vehicle wheel motor is controlled to brake according to the determined target recovery braking torque.

[0056] In this way, when the vehicle enters an emergency braking state, the current hydraulic torque remains unchanged, and the braking torque of the wheel motors with faster response speed is used to meet the vehicle's braking needs, which shortens the braking time, improves energy recovery efficiency, and enhances safety.

[0057] In another embodiment, determining the target regenerative braking torque of the wheel motor based on the current hydraulic torque and the target braking torque of the vehicle wheels includes:

[0058] The difference between the target braking torque of the vehicle wheels and the current hydraulic torque is determined as the target regenerative braking torque of the wheel motor.

[0059] In this embodiment, after determining the target braking torque of the vehicle wheels, the difference between the determined target braking torque of the vehicle wheels and the current hydraulic braking torque that remains unchanged is determined as the target recovery braking torque of the wheel motor. The method is simple and the data processing speed is fast.

[0060] In yet another embodiment, after the step of controlling the vehicle's wheel motors to brake according to the determined target regenerative braking torque, the method further includes:

[0061] If the vehicle wheels lock up, the target regenerative braking torque of the wheel motors will be reduced.

[0062] During the process of controlling the vehicle's wheel motors to brake according to a predetermined target regenerative braking torque, if the vehicle's wheels lock up, the braking torque applied to the vehicle's wheels is too high. It is necessary to reduce the braking torque applied to the locked wheels to allow the locked wheels to resume rotation. This can be achieved by keeping the current hydraulic braking torque of the wheels constant, correspondingly reducing the target regenerative braking torque of the wheel motors. For example, when the slip ratio of the vehicle's wheels exceeds a predetermined slip ratio threshold (e.g., 30%), it is determined that the vehicle's wheels have locked up.

[0063] In this embodiment, when a vehicle wheel locks up, reducing the target regenerative braking torque of the wheel motor can promptly and reliably restore the locked wheel to rotation, thus improving safety.

[0064] In yet another embodiment, after the step of reducing the target regenerative braking torque of the vehicle motor, the method further includes:

[0065] If the target regenerative braking torque of the wheel motor is less than the torque threshold and the vehicle wheels are still locked, the hydraulic braking torque of the vehicle wheels is reduced until the vehicle wheels are no longer locked. Then, the reduction of the hydraulic braking torque of the vehicle wheels is stopped, and the hydraulic braking torque of the vehicle wheels is kept constant. The difference between the target braking torque of the vehicle wheels and the reduced hydraulic braking torque is determined as the target regenerative braking torque of the wheel motor.

[0066] The torque threshold can be preset by the designer, for example, to 0. After reducing the target regenerative braking torque of the vehicle motor, when the target regenerative braking torque of the wheel motor is less than the torque threshold, the target regenerative braking torque of the wheel motor has been reduced to a minimum. If the vehicle wheels are still locked, the braking torque currently applied to the vehicle wheels is still relatively large, and it is necessary to continue to reduce the braking torque applied to the vehicle wheels. At this time, the hydraulic braking torque of the vehicle wheels can be reduced. During the process of reducing the hydraulic braking torque of the vehicle wheels, the braking torque applied to the vehicle wheels continues to decrease. When the vehicle wheels are no longer locked, the reduction of the hydraulic braking torque of the vehicle wheels can be stopped, and the difference between the target braking torque of the vehicle wheels and the reduced hydraulic braking torque is determined as the target regenerative braking torque of the wheel motor. The hydraulic braking torque is kept constant, and the wheel motor is controlled to perform anti-lock braking according to the target regenerative braking torque.

[0067] In this embodiment, when the target regenerative braking torque of the wheel motor is reduced to a small value and the wheel is still locked, the vehicle wheel can be reliably and effectively restored to rotation by reducing the hydraulic braking torque of the vehicle wheel.

[0068] In yet another embodiment, determining the target braking torque for the vehicle wheels includes:

[0069] The target braking torque of the vehicle wheels is determined based on the braking torque required by the driver, wherein the sum of the target braking torques of the vehicle wheels is less than the braking torque required by the driver.

[0070] When a vehicle is under emergency braking, the wheels may lock up, resulting in poor vehicle stability. Therefore, it is necessary to limit the sum of the target braking torques of the vehicle wheels to be less than the braking torque required by the driver to ensure vehicle stability during braking. For example, the total target braking torque, which is less than the driver's required braking torque, can be evenly distributed to each wheel.

[0071] In this embodiment, limiting the sum of the target braking torques of the vehicle wheels to less than the braking torque required by the driver can improve the braking stability of the vehicle when it is in an emergency braking state.

[0072] In yet another embodiment, the method further includes:

[0073] Determine the maximum available regenerative braking torque for the wheel motor;

[0074] If the vehicle enters a normal braking state, the target regenerative braking torque of the wheel motor is determined based on the maximum available regenerative braking torque of the wheel motor and the target braking torque of the vehicle wheels.

[0075] The hydraulic target braking torque is determined based on the target regenerative braking torque of the wheel motor.

[0076] The maximum available regenerative braking torque of the wheel motor can be considered as the maximum regenerative braking torque that the wheel motor can provide. Normal braking state refers to the braking state where the vehicle's anti-lock braking system (ABS) is not activated. When the vehicle is in normal braking state, the wheels are not locked, and the driver's required braking torque is relatively small. The target regenerative braking torque of the wheel motor can be determined based on the maximum available regenerative braking torque of the wheel motor and the target braking torque of the vehicle's wheels. The hydraulic target braking torque of the vehicle's wheels can then be determined based on the determined target regenerative braking torque of the wheel motor.

[0077] In this embodiment, when the vehicle is in a normal braking state, the target regenerative braking torque of the wheel motor can be reliably and accurately determined based on the maximum available regenerative braking torque of the wheel motor and the target braking torque of the vehicle wheels. The hydraulic target braking torque can be quickly and accurately determined based on the target regenerative braking torque of the wheel motor.

[0078] In yet another embodiment, determining the maximum available regenerative braking torque of the wheel motor includes:

[0079] Determine the driver's required braking torque;

[0080] The pre-distributed braking torque of the wheel motors is determined based on the vehicle speed and the braking torque required by the driver.

[0081] The maximum available regenerative braking torque of the wheel motor is determined based on the pre-distributed braking torque of the wheel motor, the maximum charging power of the vehicle battery, and the maximum regenerative braking power of the vehicle's wheel motor.

[0082] When the vehicle is under normal braking conditions, the wheels do not lock up, and the vehicle's braking stability is good. The driver's required braking torque is equal to the sum of the target braking torques of the vehicle's wheels. For example, the driver's required braking torque can be determined based on the brake pedal opening. The pre-distributed braking torque of the wheel motors is related to the vehicle speed and the driver's required braking torque. After determining the driver's required braking torque, the pre-distributed braking torque of the wheel motors can be determined based on the vehicle speed and the driver's required braking torque.

[0083] Different models of wheel motors have different maximum regenerative braking power, and different models of vehicle batteries have different maximum charging power at different states of charge (SOC). The maximum usable regenerative braking torque of the wheel motor is related to the pre-allocated braking torque of the wheel motor, the maximum charging power of the vehicle battery, and the maximum regenerative braking power of the vehicle's wheel motor. For example, when the maximum charging power of the vehicle battery is low, even if the maximum regenerative braking power of the wheel motor is high, the maximum usable regenerative braking torque of the wheel motor will be low.

[0084] In this embodiment, the maximum available regenerative braking torque of the wheel motor can be reliably and accurately determined based on the pre-allocated braking torque of the wheel motor, the maximum charging power of the vehicle battery, and the maximum regenerative braking power of the vehicle's wheel motor.

[0085] In another embodiment, determining the pre-distributed braking torque of the wheel motor based on the vehicle speed and the driver's required braking torque includes:

[0086] The ratio of the pre-distributed braking torque of the wheel motor to the braking torque required by the driver is determined based on the vehicle speed.

[0087] The pre-distributed braking torque of the wheel motor is determined based on the ratio.

[0088] For example, the ratio of the pre-distributed braking torque of the wheel motor to the braking torque required by the driver can be found in a predetermined correspondence as the determined ratio, which includes the correspondence between vehicle speed and the ratio.

[0089] Figure 2 This is a schematic diagram illustrating the correspondence between vehicle speed and the pre-distributed braking torque ratio of the wheel motors, provided in an exemplary embodiment. For example... Figure 2 As shown, the horizontal axis represents vehicle speed, and the vertical axis represents the ratio of the pre-distributed braking torque of the wheel motors to the braking torque required by the driver. When the vehicle speed is between 0 kph and 10 kph, the ratio of the pre-distributed braking torque of the wheel motors to the braking torque required by the driver is 0.

[0090] When the vehicle speed is between 10kph and 30kph, the ratio of the pre-distributed braking torque of the wheel motor to the braking torque required by the driver increases from 0 to 100%.

[0091] When the vehicle speed is between 30kph and 60kph, the ratio of the pre-distributed braking torque of the wheel motor to the braking torque required by the driver remains constant at 100%.

[0092] When the vehicle speed is between 60kph and 80kph, the ratio of the pre-distributed braking torque of the wheel motor to the braking torque required by the driver decreases from 100% to 0.

[0093] When the vehicle speed is greater than 80 kph, the ratio of the pre-distributed braking torque of the wheel motor to the braking torque required by the driver is 0.

[0094] Therefore, when the vehicle speed is low or high, the pre-distributed braking torque of the wheel motor is small, and the energy recovery efficiency is low.

[0095] After determining the ratio of the pre-distributed braking torque of the wheel motor to the braking torque required by the driver, the pre-distributed braking torque of the wheel motor can be calculated, for example, according to the following formula:

[0096] F f =P f ×F total

[0097] Among them, F f P represents the pre-distributed braking torque of the wheel motor; f This represents the ratio of the pre-distributed braking torque of the wheel motor to the braking torque required by the driver; F total This indicates the braking torque required by the driver.

[0098] In this embodiment, the pre-distributed braking torque of the wheel motor can be accurately and quickly determined based on the vehicle speed and the driver's required braking torque.

[0099] In another embodiment, determining the maximum available regenerative braking torque of the wheel motor based on the pre-distributed braking torque of the wheel motor, the maximum charging power of the vehicle battery, and the maximum regenerative braking power of the vehicle's wheel motor includes:

[0100] The maximum regenerative braking torque of the vehicle is determined based on the maximum charging power of the vehicle battery.

[0101] The maximum regenerative braking torque of the wheel motor is determined based on the maximum regenerative power of the wheel motor.

[0102] The minimum value among the vehicle's pre-distributed braking torque, the vehicle's maximum regenerative braking torque, and the wheel motor's maximum regenerative braking torque, and the predetermined limit torque value, is determined as the maximum available regenerative braking torque of the wheel motor.

[0103] For example, for each wheel motor of the vehicle, the maximum regenerative braking torque of the wheel motor corresponding to its maximum regenerative power can be found in a predetermined correspondence, which is used as the determined maximum regenerative braking torque of the wheel motor. This correspondence includes the relationship between the maximum regenerative power and the maximum regenerative braking torque of the wheel motor. The maximum regenerative braking torque of the vehicle's wheel motors is the sum of the maximum regenerative braking torques of each wheel motor.

[0104] For example, the maximum regenerative braking torque of the vehicle corresponding to the maximum charging power of the vehicle's battery can be found in a predetermined correspondence, which is used as the determined maximum regenerative braking torque of the vehicle. The correspondence includes the correspondence between the maximum regenerative power of the vehicle's battery and the maximum regenerative braking torque of the vehicle.

[0105] The predetermined limiting torque value can be pre-set by the designer based on experiments. When the maximum regenerative braking torque of the wheel motor is the minimum of the pre-distributed braking torque of the vehicle's wheel motor, the maximum regenerative braking torque of the vehicle, and the maximum regenerative braking torque of the wheel motor, the maximum charging capacity of the vehicle battery is greater than the maximum regenerative braking capacity of the wheel motor. When the maximum regenerative braking torque of the vehicle is the minimum of the pre-distributed braking torque of the vehicle's wheel motor, the maximum regenerative braking torque of the vehicle, and the maximum regenerative braking torque of the wheel motor, the maximum charging capacity of the vehicle battery is less than the maximum regenerative braking capacity of the wheel motor.

[0106] The limiting torque value can be considered a redundancy. After determining the minimum value among the vehicle's pre-distributed braking torque of the wheel motors, the vehicle's maximum regenerative braking torque, and the maximum regenerative braking torque of the wheel motors, the difference between the minimum value and the limiting torque value is determined as the maximum available regenerative braking torque of the wheel motors. This ensures the reliability of the determined maximum available regenerative braking torque of the wheel motors compared to directly determining the minimum value among the three.

[0107] In this embodiment, the difference between the minimum value of the vehicle's pre-distributed braking torque, the vehicle's maximum regenerative braking torque, and the maximum regenerative braking torque of the wheel motor and a predetermined limiting torque value is determined as the maximum available regenerative braking torque of the wheel motor. This avoids the occurrence of insufficient regenerative braking torque of the wheel motor during braking.

[0108] In another embodiment, determining the target regenerative braking torque of the wheel motor based on the maximum available regenerative braking torque of the wheel motor and the target braking torque of the vehicle wheels includes:

[0109] If the maximum available regenerative braking torque of the wheel motor is greater than the target braking torque of the vehicle wheel, then the target braking torque of the vehicle wheel is determined as the target regenerative braking torque of the wheel motor.

[0110] If the maximum available regenerative braking torque of the wheel motor is less than or equal to the target braking torque of the vehicle wheel, then the maximum available regenerative braking torque of the wheel motor is determined as the target regenerative braking torque of the wheel motor.

[0111] When the maximum available regenerative braking torque of the wheel motor is greater than the target braking torque of the vehicle wheels, the maximum regenerative braking capacity of the motor is sufficient to meet the braking requirements of the vehicle wheels. The braking requirements of the vehicle wheels can be met solely by the wheel motor, without needing to combine it with the hydraulic braking torque of the vehicle wheels. Therefore, the target braking torque of the vehicle wheels can be determined as the target regenerative braking torque of the wheel motor. Conversely, when the maximum available regenerative braking torque of the wheel motor is less than or equal to the target braking torque of the vehicle wheels, the maximum regenerative braking capacity of the wheel motor is insufficient to meet the braking requirements of the vehicle wheels. It is necessary to combine it with the hydraulic braking torque of the vehicle wheels to meet the braking requirements. Therefore, the maximum available regenerative braking torque of the wheel motor can be determined as the target regenerative braking torque of the wheel motor.

[0112] In this embodiment, under two different conditions—that the maximum available regenerative braking torque of the wheel motor is greater than the target braking torque of the vehicle wheel and that the maximum available regenerative braking torque of the wheel motor is less than or equal to the target braking torque of the vehicle wheel—the target braking torque of the vehicle wheel and the maximum available regenerative braking torque of the wheel motor are respectively determined as the target regenerative braking torque of the wheel motor. This allows for a reasonable determination of the target regenerative braking torque of the wheel motor under normal braking conditions.

[0113] Figure 3 This is a schematic diagram illustrating the correspondence between time, speed, and braking torque, provided in an exemplary embodiment. For example... Figure 3 As shown, the horizontal axis represents time, and the vertical axis represents speed and braking torque. Before the anti-lock braking system (ABS) is activated, the driver's required braking torque increases rapidly to its maximum value (the driver depresses the brake pedal deeply, causing the vehicle to brake suddenly), resulting in a decrease in vehicle speed and wheel speed. When the ABS is activated, the driver's required braking torque reaches its maximum value, and the vehicle wheels lock up. After the ABS is activated, the wheel hydraulic braking torque remains constant. By adjusting the wheel motors to regenerate the target braking torque, the vehicle's braking needs are met, and the vehicle speed and wheel speed decrease to 0 kph after a certain period of time.

[0114] Figure 4 This is a schematic diagram illustrating the correspondence between time, speed, and braking torque, provided in yet another exemplary embodiment. For example... Figure 4 As shown, the horizontal axis represents time, and the vertical axis represents speed and braking torque. Before the anti-lock braking system (ABS) is activated, the driver's required braking torque increases rapidly to its maximum value (the driver depresses the brake pedal deeply, causing the vehicle to brake suddenly), resulting in a decrease in vehicle speed and wheel speed. When the ABS is activated, the driver's required braking torque reaches its maximum value, and the vehicle's wheels lock up. Figure 4In this embodiment, the maximum available regenerative braking torque of the wheel motor is less than the target braking torque of the vehicle wheels. The maximum regenerative braking capacity of the wheel motor cannot meet the braking requirements of the vehicle wheels. The target regenerative braking torque provided by the wheel motor accounts for a small proportion of the target braking torque of the vehicle wheels. After the anti-lock braking function is activated, at time t1, the target regenerative braking torque of the vehicle motor decreases to 0 Nm, and the vehicle wheels are still in a locked state. Between t1 and t2, the wheel hydraulic braking torque decreases. When at time t2, the slip ratio of the vehicle wheels is less than 30%, and the reduction of the wheel hydraulic braking torque can be stopped. After time t2, the wheel hydraulic braking torque remains unchanged. By adjusting the target regenerative braking torque of the wheel motor, the wheel braking requirements are met, and the vehicle speed and wheel speed decrease to 0 kph after a certain period of time.

[0115] Based on the same inventive concept, this disclosure also provides a vehicle control device. Figure 5 This is a block diagram of a vehicle control device provided in an exemplary embodiment. Figure 5 As shown, the vehicle control device 600 includes a first determining module 601, a second determining module 602, and a first control module 603.

[0116] The first determining module 601 is used to determine the target braking torque of the vehicle wheels if the vehicle enters an emergency braking state.

[0117] The second determining module 602 is used to keep the current hydraulic torque constant and determine the target recovery braking torque of the wheel motor based on the current hydraulic torque and the target braking torque of the vehicle wheels.

[0118] The first control module 603 is used to control the vehicle's wheel motors to perform braking according to the determined target recovery braking torque.

[0119] Optionally, the second determining module 602 includes the first determining submodule.

[0120] The first determining submodule is used to determine the difference between the target braking torque of the vehicle wheels and the current hydraulic torque as the target recovery braking torque of the wheel motor.

[0121] Optionally, the vehicle control unit 600 may also include a second control module.

[0122] The second control module is used to reduce the target regenerative braking torque of the wheel motor if the vehicle wheels lock up.

[0123] Optionally, the vehicle control unit 600 may also include a third control module.

[0124] The third control module is used to reduce the hydraulic braking torque of the vehicle wheels if the target regenerative braking torque of the wheel motor is less than the torque threshold and the vehicle wheels are still locked. This reduction continues until the vehicle wheels are no longer locked. The reduction of the hydraulic braking torque is then stopped, and the hydraulic braking torque of the vehicle wheels remains unchanged. The difference between the target braking torque of the vehicle wheels and the reduced hydraulic braking torque is determined as the target regenerative braking torque of the wheel motor.

[0125] Optionally, the first determining module 601 includes a second determining submodule.

[0126] The second determining submodule is used to determine the target braking torque of the vehicle wheels based on the driver's required braking torque, wherein the sum of the target braking torques of the vehicle wheels is less than the driver's required braking torque.

[0127] Optionally, the vehicle control device 600 may also include a third determining module, a fourth determining module, and a fifth determining module.

[0128] The third determining module is used to determine the maximum available regenerative braking torque of the wheel motor.

[0129] The fourth determining module is used to determine the target regenerative braking torque of the wheel motors based on the maximum available regenerative braking torque of the wheel motors and the target braking torque of the vehicle wheels if the vehicle enters a normal braking state.

[0130] The fifth determining module is used to determine the hydraulic target braking torque based on the target regenerative braking torque of the wheel motor.

[0131] Optionally, the third determining module includes a third determining submodule, a fourth determining submodule, and a fifth determining submodule.

[0132] The third determination submodule is used to determine the driver's required braking torque.

[0133] The fourth determination submodule is used to determine the pre-distributed braking torque of the wheel motors based on the vehicle speed and the braking torque required by the driver.

[0134] The fifth determination submodule is used to determine the maximum available regenerative braking torque of the wheel motor based on the pre-allocated braking torque of the wheel motor, the maximum charging power of the vehicle battery, and the maximum regenerative braking power of the vehicle's wheel motor.

[0135] Optionally, the fourth determination submodule is also used for:

[0136] The ratio of the pre-distributed braking torque of the wheel motor to the braking torque required by the driver is determined based on the vehicle speed.

[0137] The pre-distributed braking torque of the wheel motor is determined based on the ratio.

[0138] Optionally, the fifth determination submodule is also used for:

[0139] The maximum regenerative braking torque of the vehicle is determined based on the maximum charging power of the vehicle battery.

[0140] The maximum regenerative braking torque of the wheel motor is determined based on the maximum regenerative power of the wheel motor.

[0141] The minimum value among the vehicle's pre-distributed braking torque, the vehicle's maximum regenerative braking torque, and the wheel motor's maximum regenerative braking torque, and the predetermined limit torque value, is determined as the maximum available regenerative braking torque of the wheel motor.

[0142] Optionally, the fourth determining module includes a sixth determining submodule and a seventh determining submodule.

[0143] The sixth determination submodule is used to determine the target braking torque of the vehicle wheel as the target regenerative braking torque of the wheel motor if the maximum available regenerative braking torque of the wheel motor is greater than the target braking torque of the vehicle wheel.

[0144] The seventh determination submodule is used to determine the maximum available regenerative braking torque of the wheel motor as the target regenerative braking torque of the wheel motor if the maximum available regenerative braking torque of the wheel motor is less than or equal to the target braking torque of the vehicle wheel.

[0145] Regarding the apparatus in the above embodiments, the specific manner in which each module performs its operation has been described in detail in the embodiments related to the method, and will not be elaborated upon here.

[0146] Through the above technical solution, if the vehicle enters an emergency braking state, the target braking torque of the vehicle wheels is determined, the current hydraulic torque is kept constant, and based on the current hydraulic torque and the target braking torque of the vehicle wheels, the target regenerative braking torque of the wheel motors is determined. The wheel motors are then controlled to brake according to the determined target regenerative braking torque. In this way, when the vehicle enters an emergency braking state, the current hydraulic torque is kept constant, and the braking torque of the wheel motors with faster response speed is used to meet the vehicle's braking needs, shortening the braking time, improving energy recovery efficiency, and enhancing safety.

[0147] This disclosure also provides a vehicle control device, including:

[0148] A memory on which computer programs are stored;

[0149] A processor is used to execute a computer program in memory to implement the steps of the vehicle control method provided in this disclosure.

[0150] This disclosure also provides a vehicle including the vehicle control device provided in this disclosure.

[0151] The preferred embodiments of this disclosure have been described in detail above with reference to the accompanying drawings. However, this disclosure is not limited to the specific details of the above embodiments. Within the scope of the technical concept of this disclosure, various simple modifications can be made to the technical solutions of this disclosure, and these simple modifications all fall within the protection scope of this disclosure.

[0152] It should also be noted that the various specific technical features described in the above embodiments can be combined in any suitable manner without contradiction. To avoid unnecessary repetition, this disclosure will not describe the various possible combinations separately.

[0153] Furthermore, various different embodiments of this disclosure can be combined in any way, as long as they do not violate the spirit of this disclosure, they should also be regarded as the content disclosed in this disclosure.

Claims

1. A vehicle control method, characterized in that, The method includes: If the vehicle enters an emergency braking state, determine the target braking torque of the vehicle wheels; Keeping the current hydraulic torque constant, and determining the target regenerative braking torque of the wheel motor based on the current hydraulic torque and the target braking torque of the vehicle wheels; The vehicle's wheel motors are controlled to brake according to a predetermined target recovery braking torque. Determine the maximum available regenerative braking torque of the wheel motor; Determining the maximum available regenerative braking torque of the wheel motor includes: Determine the driver's required braking torque; The pre-distributed braking torque of the wheel motor is determined based on the vehicle speed and the driver's required braking torque. The maximum available regenerative braking torque of the wheel motor is determined based on the pre-distributed braking torque of the wheel motor, the maximum charging power of the vehicle battery, and the maximum regenerative braking power of the vehicle's wheel motor. If the vehicle enters a normal braking state, the target regenerative braking torque of the wheel motor is determined based on the maximum available regenerative braking torque of the wheel motor and the target braking torque of the vehicle wheels; The hydraulic target braking torque is determined based on the target regenerative braking torque of the wheel motor.

2. The method according to claim 1, characterized in that, Determining the target regenerative braking torque of the wheel motor based on the current hydraulic torque and the target braking torque of the vehicle wheels includes: The difference between the target braking torque of the vehicle wheel and the current hydraulic torque is determined as the target regenerative braking torque of the wheel motor.

3. The method according to claim 2, characterized in that, After the step of controlling the wheel motors of the vehicle to brake according to the determined target regenerative braking torque, the method further includes: If the vehicle wheels lock up, the target regenerative braking torque of the wheel motor is reduced.

4. The method according to claim 3, characterized in that, After the step of reducing the target regenerative braking torque of the vehicle motor, the method further includes: If the target regenerative braking torque of the wheel motor is less than the torque threshold and the vehicle wheel is still locked, the hydraulic braking torque of the vehicle wheel is reduced until the vehicle wheel is no longer locked. Then, the reduction of the hydraulic braking torque of the vehicle wheel is stopped, and the hydraulic braking torque of the vehicle wheel is kept unchanged. The difference between the target braking torque of the vehicle wheel and the reduced hydraulic braking torque is determined as the target regenerative braking torque of the wheel motor.

5. The method according to claim 1, characterized in that, Determining the target braking torque for the vehicle wheels includes: The target braking torque of the vehicle wheels is determined based on the driver's required braking torque, wherein the sum of the target braking torques of the vehicle wheels is less than the driver's required braking torque.

6. The method according to claim 1, characterized in that, The step of determining the pre-distributed braking torque of the wheel motor based on the vehicle speed and the driver's required braking torque includes: The ratio of the pre-distributed braking torque of the wheel motor to the braking torque required by the driver is determined based on the vehicle speed. The pre-distributed braking torque of the wheel motor is determined based on the ratio.

7. The method according to claim 1, characterized in that, Determining the maximum available regenerative braking torque of the wheel motor based on the pre-distributed braking torque of the wheel motor, the maximum charging power of the vehicle battery, and the maximum regenerative braking power of the vehicle's wheel motor includes: The maximum regenerative braking torque of the vehicle is determined based on the maximum charging power of the vehicle battery. The maximum regenerative braking torque of the wheel motor is determined based on the maximum regenerative power of the wheel motor. The minimum value among the pre-distributed braking torque of the vehicle's wheel motor, the vehicle's maximum regenerative braking torque, and the maximum regenerative braking torque of the wheel motor, and the predetermined limiting torque value, is determined as the maximum available regenerative braking torque of the wheel motor.

8. The method according to claim 1, characterized in that, Determining the target regenerative braking torque of the wheel motor based on the maximum available regenerative braking torque of the wheel motor and the target braking torque of the vehicle wheels includes: If the maximum available regenerative braking torque of the wheel motor is greater than the target braking torque of the vehicle wheel, then the target braking torque of the vehicle wheel is determined as the target regenerative braking torque of the wheel motor. If the maximum available regenerative braking torque of the wheel motor is less than or equal to the target braking torque of the vehicle wheel, then the maximum available regenerative braking torque of the wheel motor is determined as the target regenerative braking torque of the wheel motor.

9. A vehicle control device, characterized in that, include: A memory on which computer programs are stored; A processor for executing the computer program in the memory to implement the steps of the method according to any one of claims 1-8.

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

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