针对传统真空助力制动系统无法直接应用于新能源车辆的问题,研究开发了一种集成电液制动(IEHB)系统,并形成样机。样机由中空电机、滚珠丝杠副、三腔主缸、人力缸及踏板行程模拟器等组成,集成制动助力、线控制动及再生制动等功能。设计了一种提高制动助力性能的滑模控制算法,并利用Lyapunov方程证明了该算法的稳定性。对本文算法及系统其他功能进行实车验证,结果表明:本文算法可以控制电机在三腔主缸内快速建立压力,并控制滚珠丝杠跟随踏板推杆一起运动,从而始终保持良好的脚感;系统可以实现线控及人力备份制动功能,且满足法规要求;踏板行程模拟器提供的脚感连续平滑。
Because the conventional vacuum booster brake systems cannot be applied to electric vehicles directly,an integrated electro-hydraulic brake(IEHB) system,which consists of a hollow brushless DC motor,a ball screw assembly,a 3-chamber master cylinder,a pedal cylinder and a pedal stroke simulator,was developed.The IEHB meets all the future requirements of electric vehicles and active safety technologies,such as electric brake booster,brake-by-wire,coordination with regenerative braking,etc.A sliding mode controller was proposed to improve brake booster performance of the system and Lyapunov function approach is used to ensure the controller robustness.The experimental results show that the proposed controller can control the motor to generate hydraulic pressure in the 3-chamber master cylinder quickly,and force the screw to follow with the push rod well to provide comfortable pedal feeling; the system can also realize brake-by-wire and manpower backup brake functions,and meet the requirements of the regulation; the pedal stroke simulator can generate smooth and continuous pedal feeling.