Vehicle braking control method and device and rear-drive electric vehicle

Abstract

The invention relates to a vehicle braking control method and device and a rear-drive electric vehicle. Specifically, the invention relates to a vehicle braking control method. According to the method, a front wheel state monitoring module monitors the rotating speed and acceleration of front wheels of a vehicle in real time, judges whether the vehicle passes through a deceleration strip or not and generates a deceleration strip recognition signal. According to the identification signal, the system actively cancels braking energy recovery and sliding energy recovery so as to avoid unstable deceleration caused by energy recovery. And then, the hydraulic execution control module adjusts the pressure of the hydraulic system according to the quitted energy recovery torque data so as to compensate the braking force loss caused by energy recovery quitting. According to the method, energy recovery and brake control can be dynamically adjusted, unstable deceleration caused by the deceleration strip and impact on the speed reducer are prevented, and therefore driving safety and comfort are effectively improved.

Description

Technical Field

[0001] The present invention relates to the field of electric vehicle braking control, and in particular to a vehicle braking control method and device and a rear-drive electric vehicle. Background Art

[0002] With the popularity of electric vehicles, how to improve the stability and driving experience of vehicles under specific working conditions has become a hot topic of research. In the existing technology, when electric vehicles coast at a high speed or brake over speed bumps, a large slip rate will be generated due to wheel speed jumps. There are currently two main control strategies: one is to trigger the Dynamic Traction Control (DTC) function when the slip rate exceeds a certain value to reduce braking and coasting energy recovery; the other is to increase the trigger threshold of the DTC function when the front wheel is identified to pass the speed bump and keep the energy recovery unchanged. These two strategies have their own defects. The former will lead to a reduction in the braking force of the entire vehicle and a poor driver experience; the latter may cause a greater impact on the reducer. Summary of the invention

[0003] The purpose of the present invention is to provide a braking control method for a rear-wheel drive electric vehicle when passing over a speed bump. Through the coordinated work of a speed bump recognition module, an energy recovery control module and a hydraulic execution control module, energy recovery is actively exited when the vehicle passes over a speed bump, and corresponding hydraulic pressure is established to ensure braking effect and driving stability.

[0004] In order to achieve the above-mentioned purpose, the present application provides a braking control method and device for a rear-wheel drive electric vehicle when the rear-wheel drive electric vehicle passes over a speed bump, and the rear-wheel drive electric vehicle.

[0005] According to a first aspect of an embodiment of the present disclosure, a braking control method for a rear-wheel drive electric vehicle when passing over a speed bump is provided, the method comprising: S1, monitoring the front wheel status of the rear-wheel drive electric vehicle in real time, and judging whether the rear-wheel drive electric vehicle is passing through a speed bump according to the front wheel status; S2, when it is determined that the rear-drive electric vehicle is passing through a speed bump, generating a speed bump identification signal; S3, calculating, according to the speed bump identification signal, a torque change rate required to cancel the energy recovery torque of the rear-wheel drive electric vehicle in an energy recovery state; S4, adjusting the output torque of the rear-wheel drive electric vehicle according to the torque change rate, thereby canceling the energy recovery torque of the rear-wheel drive electric vehicle in the energy recovery state; S5, performing torque compensation on the braking system of the rear-wheel drive electric vehicle according to the cancelled energy recovery torque; S6, braking the rear-wheel drive electric vehicle through the braking system after torque compensation.

[0006] Optionally, step S1 includes: Real-time monitoring of the rotation speed and acceleration of the front wheels of the rear-wheel drive electric vehicle; Whether the rear-drive electric vehicle is passing through a speed bump is determined according to the real-time rotation speed and real-time acceleration of the front wheels.

[0007] Optionally, step S2 includes: When it is determined that the rear-wheel drive electric vehicle is passing through a speed bump, a speed bump identification signal including a timestamp and the speed, acceleration, and front wheel status of the rear-wheel drive electric vehicle is generated.

[0008] Optionally, step S3 includes: Calculating a target torque after canceling the braking energy recovery torque and the coasting energy recovery torque according to the speed bump identification signal, the braking energy recovery torque of the rear-wheel drive electric vehicle in the braking energy recovery state, and the coasting energy recovery torque of the rear-wheel drive electric vehicle in the coasting energy recovery state; The torque change rate at which the torque of the driving motor of the rear-wheel drive electric vehicle is adjusted to the target torque in the current state is calculated as the torque change rate required to cancel the energy recovery torque of the rear-wheel drive electric vehicle in the energy recovery state.

[0009] Optionally, step S4 includes: According to the difference between the energy recovery torque to be cancelled and the target torque, a smoothly adjusted rate is set to ensure a gradual change in the output torque; The output torque of the rear-wheel drive electric vehicle is controlled according to the smooth adjustment rate.

[0010] Optionally, step S5 includes: Calculate the corresponding torque compensation pressure according to the cancelled energy recovery torque; generating a corresponding compensation torque according to the torque compensation pressure; Torque compensation is performed on the brake system of the rear-wheel drive electric vehicle according to the compensation torque.

[0011] Optionally, step S6 includes: According to the required braking intensity and the current vehicle state, the speed and output torque of the motor of the rear-wheel drive electric vehicle are adjusted by the torque-compensated braking system to perform braking; During the braking process, the braking torque is provided by the hydraulic system of the rear-wheel drive electric vehicle.

[0012] According to a second aspect of an embodiment of the present disclosure, a vehicle braking control device is provided, which is used to perform braking control when a rear-drive electric vehicle passes through a speed bump, and includes the following modules: A front wheel status monitoring module, used to monitor the front wheel status of the rear-wheel drive electric vehicle in real time, and determine whether the rear-wheel drive electric vehicle is passing through a speed bump according to the front wheel status; A speed bump identification module, configured to generate a speed bump identification signal when it is determined that the rear-drive electric vehicle is passing through a speed bump; a torque change rate calculation module, used to calculate the torque change rate required to cancel the energy recovery torque of the rear-drive electric vehicle in the energy recovery state according to the speed bump identification signal; an output torque adjustment module, used for adjusting the output torque of the rear-wheel drive electric vehicle according to the torque change rate, thereby canceling the energy recovery torque of the rear-wheel drive electric vehicle in an energy recovery state; A torque compensation module, used for performing torque compensation on a braking system of the rear-wheel drive electric vehicle according to the cancelled energy recovery torque; The brake control module is used to brake the rear-wheel drive electric vehicle through a brake system after torque compensation.

[0013] Integrated intelligent decision-making module to analyze historical data and real-time feedback, predict potential braking needs, and adjust hydraulic pressure and motor output in advance.

[0014] Optionally, the brake control device further includes: An integrated intelligent decision-making module is used to analyze historical working data and real-time feedback information of the rear-wheel drive electric vehicle, predict potential braking needs, and adjust the hydraulic system pressure and motor output of the rear-wheel drive electric vehicle in advance according to the prediction results.

[0015] According to a third aspect of an embodiment of the present disclosure, there is provided a rear-wheel drive electric vehicle comprising the vehicle brake control device as described above.

[0016] The present invention provides an innovative braking control method for a rear-wheel drive electric vehicle when passing over a speed bump, which can effectively solve the problems of vehicle deceleration loss and impact on the reducer in the prior art. By real-time monitoring and dynamic adjustment of energy recovery and hydraulic pressure, the present invention not only improves the driving stability of the vehicle, but also improves the driving experience of the driver. The implementation of this method will provide a strong guarantee for the safety and comfort of rear-wheel drive electric vehicles. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without paying creative labor.

[0018] Figure 1 A flow chart of a vehicle braking control method provided for one embodiment of the present application; Figure 2 It is a functional module diagram of a vehicle braking control device provided by an embodiment of the present application. DETAILED DESCRIPTION

[0019] The technical solutions in the embodiments of the present invention will be described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0020] The invention relates to a braking control method for a rear-drive electric vehicle when passing over a speed bump, aiming to improve the stability and driving experience of the vehicle under specific working conditions.

[0021] One embodiment of the present invention provides a braking control method for a rear-drive electric vehicle when passing over a speed bump. Figure 1 , the method comprises the following steps: S1, real-time monitoring of the front wheel status: real-time monitoring of the front wheel status of the rear-wheel drive electric vehicle, and judging whether the rear-wheel drive electric vehicle is passing through a speed bump by the front wheel status. This step monitors the speed and acceleration of the front wheels in real time by installing high-precision sensors on the front wheels of the rear-wheel drive electric vehicle. These sensors can collect data at a high frequency and transmit it to the central control module. The central control module uses complex algorithms to analyze this data to determine whether the front wheels are in a state of passing through a speed bump. Through this real-time monitoring, the system can quickly respond to changes in the vehicle status and provide an accurate information basis for subsequent control decisions. The effectiveness of this process directly affects the execution of subsequent steps, ensuring that the vehicle can make corresponding adjustments in time when passing through a speed bump to avoid possible driving instability.

[0022] S2, generating a speed bump identification signal: when it is determined that the rear-drive electric vehicle is passing through a speed bump, a speed bump identification signal is generated. After determining that the front wheel state meets the conditions for passing through the speed bump, the central control module generates a speed bump identification signal. This signal is not only a confirmation of the front wheel state, but also an instruction for subsequent system operations. The signal will be quickly sent to the energy recovery control module and the hydraulic execution control module to start subsequent control procedures. This process ensures that the vehicle can react quickly when it identifies a speed bump, avoiding vehicle instability or uncomfortable driving experience caused by delays. At the same time, the timely generation of identification signals also provides the necessary trigger conditions for subsequent energy recovery exit and hydraulic pressure adjustment.

[0023] S3, calculate the rate of change of the exit torque: according to the speed bump identification signal, calculate the rate of change of the torque required to cancel the energy recovery torque of the rear-wheel drive electric vehicle in the energy recovery state. After identifying the speed bump signal, the system will calculate the target exit torque based on the current torque values ​​of braking energy recovery and coasting energy recovery. This calculation process uses a set algorithm to accurately reduce the rate of change from the current value to the target value and generate corresponding adjustment instructions. Through this mechanism, the system can ensure that the exit process of energy recovery is smooth, avoid sudden deceleration or acceleration of the vehicle when passing through the speed bump, and thus improve driving comfort and safety. Accurately calculate the rate of change of the exit torque so that the vehicle can maintain a stable dynamic response when driving on the speed bump.

[0024] S4, actively exit energy recovery: adjust the output torque of the rear-wheel drive electric vehicle according to the torque change rate, thereby canceling the energy recovery torque of the rear-wheel drive electric vehicle in the energy recovery state. During normal driving of the vehicle, the system is in an energy recovery state, recovering the energy generated during braking and coasting. When the system recognizes the signal that the current wheel passes through a speed bump, it will automatically adjust the energy recovery strategy and actively exit the energy recovery of braking and coasting. This mechanism is designed to avoid unstable vehicle deceleration caused by energy recovery, thereby improving driving comfort and safety. By actively exiting energy recovery, the vehicle can maintain a stable driving state when passing through a speed bump, reducing the driver's sense of forward rush and discomfort, and optimizing the overall driving experience.

[0025] S5, torque-compensated hydraulic pressure adjustment: torque compensation is performed on the braking system of the rear-wheel drive electric vehicle according to the canceled energy recovery torque. After actively exiting energy recovery, the system calculates the required target hydraulic pressure based on the canceled energy recovery torque data and sends it to the hydraulic execution control module. The module adjusts the output of the hydraulic pump based on these data to supplement the torque reduced due to the exit of braking and coasting energy recovery. In this way, the system can ensure that the braking effect of the vehicle is not affected when energy recovery is exited. The adjustment of hydraulic pressure is achieved through a real-time feedback mechanism to ensure that the system can respond to changes in vehicle status in a timely manner, maintain stable braking performance, and improve driving safety.

[0026] S6, real-time hydraulic pressure control: The rear-wheel drive electric vehicle is braked by a torque-compensated braking system. During braking, the system adjusts the hydraulic pressure of the hydraulic execution control module in real time by controlling the speed and torque of the motor to maintain the braking effect of the vehicle. The speed and torque regulation of the motor directly affect the pressure output of the hydraulic system, thereby ensuring that the hydraulic pressure can respond in time and supplement the corresponding braking force during the energy recovery exit process. This mechanism ensures that the vehicle always maintains stable braking performance during driving, improving safety and driving experience. By dynamically adjusting the hydraulic pressure, the system can effectively respond to different driving conditions, ensure the smooth driving of the vehicle when passing through speed bumps, and avoid causing discomfort to the driver.

[0027] The second aspect of the present invention also provides a braking control device, which can be used to implement the braking control method for a rear-wheel drive electric vehicle when it passes over a speed bump as described in the above embodiment. Figure 2 The braking control device 100 includes a front wheel state monitoring module 101, a speed bump identification module 102, a torque change rate calculation module 103, an output torque adjustment module 104, a torque compensation module 105, a braking control module 106, and an intelligent decision-making module 107.

[0028] Specifically, the front wheel state monitoring module 101 is used to monitor the front wheel state of the rear-wheel drive electric vehicle in real time, and judge whether the rear-wheel drive electric vehicle is passing through a speed bump through the front wheel state. This module collects dynamic data of the front wheel through a high-precision sensor installed on the front wheel, and transmits this data to the speed bump identification module 102. Accurate monitoring of the front wheel state can timely judge whether the front wheel is in a state of passing through a speed bump, providing an important basis for subsequent control decisions, and ensuring that the vehicle maintains stability during driving; The speed bump identification module 102 is used to generate a speed bump identification signal when it is determined that the rear-drive electric vehicle is passing through a speed bump. As a central control module, this module is responsible for receiving data from the front wheel state monitoring module 101 and analyzing and processing it using a built-in algorithm. When it is determined that the front wheel state meets the conditions for passing through a speed bump, the speed bump identification module generates a speed bump identification signal and sends it to the torque change rate calculation module 103 and the output torque adjustment module 104 to start the subsequent control program. The efficient computing capability of this module ensures the rapid response of the system and improves the safety and driving experience of the vehicle.

[0029] The torque change rate calculation module 103 is used to calculate the torque change rate required to cancel the energy recovery torque of the rear-drive electric vehicle in the energy recovery state according to the speed bump identification signal. This module is responsible for calculating the torque change rate that needs to be adjusted due to speed bump identification. By analyzing the vehicle driving state and the front wheel monitoring data, the module can determine the torque value that needs to be adjusted, providing a basis for subsequent torque compensation and hydraulic pressure adjustment.

[0030] The output torque adjustment module 104 is used to adjust the output torque of the rear-drive electric vehicle according to the torque change rate, so as to cancel the energy recovery torque of the rear-drive electric vehicle in the energy recovery state. The module adjusts the output torque of the hydraulic pump according to the output of the torque change rate calculation module 103. By accurately controlling the pressure output of the hydraulic system, it is ensured that the braking effect of the vehicle is not affected when energy recovery is exited.

[0031] The torque compensation module 105 is used to perform torque compensation on the braking system of the rear-drive electric vehicle according to the canceled energy recovery torque. This module is responsible for controlling the motor operation state of the hydraulic execution control module. By adjusting the motor speed and torque, the torque compensation module can adjust the hydraulic pressure in real time to supplement the braking force reduced by the withdrawal of energy recovery. The dynamic adjustment capability of this module ensures that the hydraulic system can respond to changes in the vehicle state in a timely manner and maintain stable braking performance.

[0032] The brake control module 106 is used to brake the rear-drive electric vehicle through a torque-compensated brake system. This module is responsible for the comprehensive management of the entire brake control process to ensure that the vehicle can decelerate smoothly and maintain safe braking performance when passing through a speed bump. The brake control module makes decisions based on the input data of each submodule and coordinates the work of each module.

[0033] The intelligent decision module 107 is used to analyze the historical working data and real-time feedback information of the rear-wheel drive electric vehicle, predict potential braking needs, and adjust the hydraulic system pressure and motor output of the rear-wheel drive electric vehicle in advance according to the prediction results. This module uses advanced algorithms and data analysis technology to comprehensively evaluate the vehicle's driving status, front wheel monitoring data, and speed bump identification information to make intelligent decisions to optimize the braking control strategy. The intelligent decision module can dynamically adjust the braking strategy according to real-time data to improve the safety and driving comfort of the vehicle.

[0034] Through the coordinated work of these seven modules, the system can effectively control the vehicle's braking process to ensure safety and stability.

[0035] Another embodiment of the present invention further provides a rear-wheel drive electric vehicle, which adopts the brake control device described in the above embodiment.

[0036] The rear-drive electric vehicle includes four wheels. The braking control method is used to monitor the dynamic state of the vehicle in real time through the coordinated work of the speed bump recognition module, the energy recovery control module and the hydraulic execution control module, and dynamically adjust the energy recovery and hydraulic pressure according to the driver's braking request and road condition changes, thereby effectively avoiding deceleration loss and vehicle impact. In addition, the system's intelligent feedback mechanism can timely limit the intensity of energy recovery according to different types of speed bumps and changes in slip rate, ensuring that the vehicle maintains a stable braking effect when passing over speed bumps, and improving the driver's sense of control and comfort. Through this comprehensive braking control solution, it is ensured that the rear-drive electric vehicle can provide a safe and smooth driving experience under various driving conditions.

[0037] Those skilled in the art will readily appreciate other embodiments of the present disclosure after considering the specification and practicing the invention disclosed herein. This application is intended to cover any variations, uses, or adaptations of the present disclosure that follow the general principles of the present disclosure and include common knowledge or customary techniques in the art that are not disclosed in the present disclosure. The specification and examples are intended to be exemplary only, and the true scope and spirit of the present disclosure are indicated by the following claims. It should be understood that the present disclosure is not limited to the exact structures that have been described above and shown in the drawings, and that various modifications and changes may be made without departing from the scope thereof. The scope of the present disclosure is limited only by the appended claims.

Claims

1. A vehicle braking control method for performing braking control when a rear-drive electric vehicle passes through a speed bump, characterized in that: The following steps are involved: S1, monitoring the front wheel status of the rear-wheel drive electric vehicle in real time, and judging whether the rear-wheel drive electric vehicle is passing through a speed bump according to the front wheel status; S2, when it is determined that the rear-drive electric vehicle is passing through a speed bump, generating a speed bump identification signal; S3, calculating, according to the speed bump identification signal, a torque change rate required to cancel the energy recovery torque of the rear-wheel drive electric vehicle in an energy recovery state; S4, adjusting the output torque of the rear-wheel drive electric vehicle according to the torque change rate, thereby canceling the energy recovery torque of the rear-wheel drive electric vehicle in the energy recovery state; S5, performing torque compensation on the braking system of the rear-wheel drive electric vehicle according to the cancelled energy recovery torque; S6, braking the rear-wheel drive electric vehicle through the braking system after torque compensation.

2. The vehicle braking control method according to claim 1, characterized in that: The step S1 comprises: Real-time monitoring of the rotation speed and acceleration of the front wheels of the rear-wheel drive electric vehicle; Whether the rear-drive electric vehicle is passing through a speed bump is determined according to the real-time rotation speed and real-time acceleration of the front wheels.

3. The vehicle braking control method according to claim 1, characterized in that: The step S2 comprises: When it is determined that the rear-wheel drive electric vehicle is passing through a speed bump, a speed bump identification signal including a timestamp and the speed, acceleration, and front wheel status of the rear-wheel drive electric vehicle is generated.

4. The vehicle braking control method according to claim 1, characterized in that: The step S3 comprises: Calculating a target torque after canceling the braking energy recovery torque and the coasting energy recovery torque according to the speed bump identification signal, the braking energy recovery torque of the rear-wheel drive electric vehicle in the braking energy recovery state, and the coasting energy recovery torque of the rear-wheel drive electric vehicle in the coasting energy recovery state; The torque change rate at which the torque of the driving motor of the rear-wheel drive electric vehicle is adjusted to the target torque in the current state is calculated as the torque change rate required to cancel the energy recovery torque of the rear-wheel drive electric vehicle in the energy recovery state.

5. The vehicle braking control method according to claim 1, characterized in that: In step S4, adjusting the output torque of the rear-wheel drive electric vehicle according to the torque change rate includes: According to the difference between the energy recovery torque to be cancelled and the target torque, a smoothly adjusted rate is set to ensure a gradual change in the output torque; The output torque of the rear-wheel drive electric vehicle is controlled according to the smooth adjustment rate.

6. The vehicle braking control method according to claim 1, characterized in that: The step S5 comprises: Calculate the corresponding torque compensation pressure according to the cancelled energy recovery torque; generating a corresponding compensation torque according to the torque compensation pressure; Torque compensation is performed on the brake system of the rear-wheel drive electric vehicle according to the compensation torque.

7. The vehicle braking control method according to claim 1, characterized in that: The step S6 comprises: According to the required braking intensity and the current vehicle state, the speed and output torque of the motor of the rear-wheel drive electric vehicle are adjusted by the torque-compensated braking system to perform braking; During the braking process, the braking torque is provided by the hydraulic system of the rear-wheel drive electric vehicle.

8. A vehicle brake control device, used for performing brake control when a rear-drive electric vehicle passes through a speed bump, characterized in that: include: A front wheel status monitoring module, used to monitor the front wheel status of the rear-wheel drive electric vehicle in real time, and determine whether the rear-wheel drive electric vehicle is passing through a speed bump according to the front wheel status; A speed bump identification module, configured to generate a speed bump identification signal when it is determined that the rear-drive electric vehicle is passing through a speed bump; a torque change rate calculation module, used to calculate the torque change rate required to cancel the energy recovery torque of the rear-drive electric vehicle in the energy recovery state according to the speed bump identification signal; an output torque adjustment module, used for adjusting the output torque of the rear-wheel drive electric vehicle according to the torque change rate, thereby canceling the energy recovery torque of the rear-wheel drive electric vehicle in an energy recovery state; A torque compensation module, used for performing torque compensation on a braking system of the rear-wheel drive electric vehicle according to the cancelled energy recovery torque; The brake control module is used to brake the rear-wheel drive electric vehicle through a brake system after torque compensation.

9. The vehicle brake control device according to claim 8, characterized in that: Also includes: An integrated intelligent decision-making module is used to analyze historical working data and real-time feedback information of the rear-wheel drive electric vehicle, predict potential braking needs, and adjust the hydraulic system pressure and motor output of the rear-wheel drive electric vehicle in advance according to the prediction results.

10. A rear-wheel drive electric vehicle, characterized in that: It comprises a vehicle brake control device as claimed in claim 8 or 9.

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