模糊PID控制策略在电动助力转向系统中的应用

Application of Fuzzy-PID Control Algorithm in Electric Power Steering System

助力转向控制策略是EPS系统的核心技术之一。为提高电动转向系统的动态响应速度和抗干扰能力,经分析采用模糊PID控制策略实现助力控制。模糊控制器以电流误差及误差变化率为输入,电机电压为输出,根据设定的模糊控制规则在线调整比例系数、微分系数和积分系数,以使系统性能达到预定要求。应用Matlab软件进行了计算机仿真,仿真结果表明基于模糊PID控制策略的EPS比传统PID控制具有更好的助力特性和抗干扰能力。

The control strategy is one of the core technologies in EPS system. In order to improve the speed of dynamic response and the ability of resisting disturbance of the system, fuzzy PID controller is designed after analysis, in which, the current error and the variety rate of the current error are inputs and the voltage of the motor is the output, and the proportional factor, the differential factor and the integral factor are adjusted on-line according to the performance of the system. A simulation using Matlab is performed, and the simulation result shows that the fuzzy PID controller has more satisfactory steering characteristics and ability of resisting disturbance than the conventional PID controller.