Brake energy feedback control method of pure electric automobile

Abstract

The invention discloses a brake energy feedback control method of a pure electric automobile. The method comprises the following steps of: judging whether a brake signal exists, if so, judging whether an ABS (antilock braking system) works, and if the ABS works, enabling a brake force Fm of a motor to be 0, enabling the front axle brake force Ff and the rear axle brake force Fb to be controlled by the ABS; if the ABS dose not work, adjusting based on the fact whether the maximum brake force Fmax provided by the motor currently meets the brake threshold value F, the sliding rate threshold value S of the front axle wheels and other factors required by a driver; if no brake signal exits, judging whether the automobile is in a sliding state, if so, judging whether a current speed V is greater than the sliding speed threshold value V0, if V is greater than V0, controlling the motor to provide the brake force Fh needed by over-speed sliding of the automobile, and if V is less than or equal to V0, requiring no braking for the automobile; and repeating the steps till the driver steps on an acceleration pedal or the automobile stops moving, ending the brake. By the method in the invention, the use efficiency of the entire automobile energy can be increased.

Description

technical field [0001] The invention belongs to the technical field of pure electric vehicles, and relates to a braking energy feedback control method for pure electric vehicles, in particular to a braking energy feedback control method for pure electric vehicles with front axle electric drive and electric and mechanical composite braking. Background technique [0002] It is impossible for the driving motor of a pure electric vehicle to completely stop rotating immediately after the power is cut off. It always rotates for a period of time under the inertia of itself and the load it carries before stopping. Therefore, in today's tight energy supply, using the remaining energy in the braking process of the drive motor has naturally become a hot spot in research and development. [0003] The methods of motor braking can be divided into two categories: mechanical braking and electrical braking. Electric braking can be divided into three forms: reverse braking, energy consumptio...

AI Technical Summary

Problems solved by technology

[0004] In the existing braking energy feedback control method for pure electric vehicles, it is first necessary to accurately identify the current road surface adhesion coefficient, which is difficult to obtain satisfactory results in practical applications; secondly, after the ABS works, the braking energy feedback is passively stopped, It is impossible to actively avoid the occurrence of wheel lock before the ABS works; finally, it cannot actively avoid the occurrence of vehicle shaking when the vehicle is braking or coasting

Images