Research on simulation and intelligent control strategy of a automobile's steering system

LI Cheng; HONG Cheng; GUO Shun; CAI Zhijun

doi:10.16579/j.issn.1001.9669.2026.04.012

Abstract：[Objective]This study focuses on the steering performance of automotive electric power steering system under various operating conditions.Taking a certain domestic vehicle model as the research subject,it aims to optimize its assist characteristics and control strategy to enhance steering ease and road feel.[Methods]Firstly,a co-simulation platform was established using CARSIM and Matlab/Simulink software to develop an accurate dynamic model of the steering system.A linear assist characteristic curve was selected to provide a basis for subsequent control strategy research.Secondly,the steering resistance torque and ideal steering wheel torque at different vehicle speeds were analyzed to determine the variation law of assist gain coefficients with respect to speed.Thirdly,a proportional-integral-derivative(PID)current control strategy based on bridge circuit pulse-width modulation(PWM)was designed to improve current response speed and control accuracy.Finally,the effectiveness of the control strategy was validated through vehicle tests on steering ease and intermediate position steering performance.[Results]Simulation and test results indicate that with the proposed control strategy,the maximum applied torque on the steering wheel during low-speed maneuvers was 5.83 N·m,comparable to 5.60 N·m of competitive models using traditional PID control,thereby maintaining good steering ease.In high-speed intermediate position steering tests,the gradient of steering wheel torque at zero lateral acceleration increased by 25.5%(reaching 17.32 N·m/g),while at 0.1g lateral acceleration,it increased by 37.47%(reaching 15.30 N·m/g),significantly improving road feel during high-speed driving.