前驱电动汽车防抱死制动中滑移率控制的动态负载模拟

Dynamic Load Emulation of Slip Ratio Control in Anti-lock Braking of a Front-axle-drive Electric Vehicle

本文中旨在研究在试验室台架上准确模拟电动汽车防抱死制动过程电制动系统的动态机械负载,实现滑移率控制策略的台架测试。针对某一前轴驱动式电动汽车,在MATLAB/Simulink平台上建立了考虑传动系半轴特性的整车动力学模型和台架模型,选取了一种电机与液压制动力共同完成滑移率调节的控制策略作为测试对象。在此基础上提出了两种动态负载模拟方法,即前馈法和逆模型法,进行了不同路面滑移率控制效果台架测试的仿真,并与负载模拟PI法进行了对比。结果表明,前馈法和逆模型法的滑移率模拟误差大幅减小,提升了防抱死制动的台架测试精度,使滑移率控制效果能得到正确评价。

The study in this paper aims at accurately emulating the dynamic mechanical loads of electric brake system of electric vehicle in anti-lock braking process on test bench to fulfill the bench test on slip ratio con-trol strategy. Specifically,a dynamics model for a front axle drive electric vehicle with consideration of the character-istics of its axle shaft and a test bench model are established with MATLAB/Simulink, and a control strategy for slip ratio regulation concurrently fulfilled by electric motor and hydraulic braking force is selected as test object. On this basis,two dynamic load emulation schemes, i. e. feed-forward compensation method and inverse dynamics model method are put forward for simulations of bench test on slip ratio control effects on different road surfaces with their results compared with that of PI control scheme. The results show that compared with PI control scheme, the meth-ods of feed-forward compensation and inverse model have much smaller error in slip-ratio emulation with higher ac-curacy in bench test for anti-lock braking,enabling the correct evaluation of slip-ratio control effects.