基于模糊与遗传优化PID的电动助力转向系统的设计与实现

Design and Implementation of Vehicle EPS System Based on Fuzzy and Genetic Optimization PID Algorithm

摘要:

针对电动助力转向(EPS)系统设计时路感不清晰合理的问题,提出了一种基于模糊推理的电动助力转向目标电流的确定方法；针对传统PID控制参数难整定的问题,设计了一种基于遗传优化PID的控制算法,快速跟随目标电流的变化,达到控制电机输出转矩的目的。为了缩短研发周期和降低成本,基于dSPACE,搭建了EPS半实物仿真实验平台并进行实验测试研究。结果表明,基于模糊方法确定的目标电流,路感清晰合理,满足低速轻便性和高速稳定性,遗传优化的PID控制器响应速度快,超调量小于5%,实现了的良好的助力效果。 

Abstract:

In view of unintelligibility and irrationality of road feel, the target current’s determination method of EPS is proposed based on a fuzzy algorithm. For the difficulty to set PID parameters, the PID controller optimized by a genetic algorithm is used to fast track target current to control the output torque. In order to shorten the software development cycle and cut the development cost down, the semi-physical simulation test bench is built based on dSPACE. The experimental research is done. The result shows that the designed determination method of target current based on fuzzy algorithm makes the road feel clear and reasonable, and meets the demand of easiness at low speed and stability at high speed. Genetic optimization PID controller’s response is fast, and the overshoot is less than 5%, and achieves the better power steering effect.