Electronic hydraulic braking system and control method thereof

Abstract

The invention discloses an electronic hydraulic brake system and a control method thereof. The system comprises a brake pedal, a main cylinder, a hydraulic pump, a wheel brake, a liquid storage tank, a high-pressure energy accumulator, a pedal feeling simulator, a hydraulic control unit and a driving motor. The driving motor drives the hydraulic pump to pump brake fluid from the fluid storage tank into the high-pressure energy accumulator to be stored, and the brake fluid serves as a pressure source of the system. The pedal feeling simulator is controlled by an electromagnetic valve and provides brake foot feeling feedback for a driver. The accurate electronic hydraulic braking model is obtained, and the state of the braking system is accurately monitored; a pressure increasing valve and a pressure reducing valve are controlled according to an expected wheel cylinder pressure value and a braking system state through a nonlinear backstepping method control strategy, so that the wheel cylinder pressure is adjusted to follow the expected value, appropriate parameter values are determined in a phase trajectory analysis and time domain analysis mode, and the method has good robustness and is suitable for large-scale popularization and application. The pressure of the wheel cylinder can be accurately and quickly adjusted, and the safety performance of a vehicle is enhanced.

Description

technical field [0001] The invention belongs to the technical field of automobile brake systems, and in particular relates to an electronic hydraulic brake system and a control method thereof. Background technique [0002] Electrohydraulic braking system has become a current research hotspot because of its high modularity, compact structure, high braking efficiency and no vacuum device. However, it uses electronic components to replace some of the mechanical components of the traditional hydraulic braking system. It is a mechanical, electrical and hydraulic hybrid system. Therefore, the system has strong nonlinear characteristics, including the compressibility of brake fluid, braking Due to the hysteresis effect of the pipeline, the damping effect of the solenoid valve, etc., it is very difficult to control the pressure of the brake wheel cylinder accurately and quickly due to these non-linear characteristics. Therefore, how to accurately and quickly control the brake wheel...

AI Technical Summary

Problems solved by technology

[0004] However, the existing technologies are almost all non-model-based control methods, some characteristics of the braking system are ignored when designing the control strategy, and it is difficult to accurately monitor the state of the braking system

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