Research On Dynamic Simulation Of The Electric Power Steering System

Nowadays, electric power steering System has become the focus of researching. Thedevelopment of the test bench research is an important implication for the study of the EPS system.The steering resistance is the most critical factor in the study of the test bench. How to output the loadaccurately and quickly is not only a key issue of the test bench research, but also the prerequisite andnecessary condition to complete the test bench.In this paper, the dynamic simulation of electric power steering system is theoretical researched.A program of the load force in different operating conditions for the test bench is put forward, themain research contents are as follows:(1) Compare a variety of commonly used EPS test bench load force loading scheme, A programof the load force in different operating conditions for the test bench is put forward. The workingprinciple of the test bench is analyzed, based on the main technical performance indicators and thebasic functions of the test bench the EPS test bench’s overall layout is planned and designed.(2) Based on the requirements of the EPS test bench load forces, the load force output of the fulloperating conditions is researched. The steering wheel resistance torque is analyzed. Combined withvehicle dynamics, input the steering wheel angle and output the force to the rack, the vehicledynamics simulation model is built in Matlab/Simulink. real-time calculate the corresponding loadforce of the test bench depending on the model, the vehicle speed, steering wheel angle and torque.(3) According to the national standards, actual driving tests under many conditions are done.Compared the real vehicle tests and the model simulation results, the simulation and experimentalresults of the load force are basically the same. The function of the load force applied to the test benchin all operating conditions is achieved. Output load force changes uniformly, the meet of the EPSassist control, back to the positive control and damping control strategy debug can be met.(4) Assist Characteristic of EPS is analyzed. Linear assist characteristic model is built.Combined with vehicle dynamics model for co-simulation, the steering System test bench model isbuilt by using ADAMS/View. The ADAMS model is built as a virtual EPS steering test bench. Theco-simulation results show that the steering wheel torque under different operating conditions in theproposed scheme is closed to the actual situation. The requirements of the test bench load forcechanges are met at different speeds. Compared with the load force is applied in the spring as thedevice in test bench has obvious advantages.