Research Of Electric Power Steering System Based On Fuzzy PID Control

With the continuous improvement of vehicle performance,the rapid development of the automotive industry,more and more cars equipped with electric power steering system(EPS).EPS system is assisted by assisting the motor to assist the driver to complete the steering,with the help of real-time adjustment,road feeling good,environmental and safety advantages widely accepted by the market.Safety,energy saving and environmental protection are the future development direction of automobile steering system,so the EPS system has been a hotspot in recent years.Firstly,this paper analyzed the research status of EPS system at home and abroad,putted forward the problems and development direction of EPS system,expounded the working principle,components and structure characteristics of EPS system,and carries out multi-body dynamics analysis,established the EPS system Mathematical model,introduced the virtual prototyping technology,and established the vehicle simulation model by ADAMS software.According to the characteristics of EPS system and the requirement of the assist characteristic,the various parameters of the linear assist characteristic curve are determined and the MALAB/simulink model is established.Aimed at the assist characteristic of EPS system,this paper designed the assistant current controller based on traditional PID control and adaptive fuzzy PID control,and established the EPS system model by the MALAB/simulink software.Considering the influence of pavement adhesion coefficient on EPS system,this paper proposes a pavement recognition control strategy in order to improve EPS system safety and steering sensation.This strategy can increase the steering wheel torque when the vehicle is driving with low road surface adhesion coefficient,so as to enhance the driver’s steering feel.Finally,the co-simulation model of ADAMS and MATLAB is established.This paper analyzed the established current controller and system control strategy through the cosimulation method.The simulation results show that the adaptive fuzzy PID control algorithm has a faster response speed and better tracking performance compared with the traditional PID control algorithm.The EPS control system designed in this paper has better steering lightness and road feeling.The EPS system with pavement recognition compensation strategy can increase the steering wheel torque in low road friction coefficient,and improve steering road feeling and driving safety.