防抱死制动系统的滑模变结构控制方法研究

Research on Sliding Mode Controller of Anti-lock Braking System

防抱死系统(ABS)在工作过程中具有高度非线性、时变性以及不确定性等特点。滑模变结构控制法能够使系统在一定特性下沿规定的状态轨迹作小幅度、高频率运动,保持非线性系统的稳定性,通过简化空气阻力、车辆滚动阻力和纵向惯性力对系统的干扰,建立了单轮车辆的系统动力学模型和ABS系统仿真模型;以车轮最佳滑移率为控制目标,采用滑模变结构控制方法,运用MATLAB/simulink软件进行了计算和分析,考察了滑移率和制动力矩随制动时间的变化规律。研究结果表明:该方法能够使车轮始终处于最佳滑移率范围,提高ABS系统制动效率,表明该方法在ABS控制中具有良好效果。

The anti-lock braking system（ABS） used in automobiles has the characteristic of the high nonlinearity, time-varying characteristics and uncertainty. The sliding mode controller can make such system move with high frequency within a narrow range according to specified state trajectory, and make such nonliear system steady. Based on simplifying the air resistance, vehicle rolling resistance and so on, the system dynamics model and the ABS model were built for the single-wheel automobile. Taking the slip rate as the target, and using the sliding mode controller, the control model was built under the environment of MATLAB/simulink. The simulation result shows that the wheel is always near the optimal slip rate and the ABS brake efficiency is improved.