Characteristic Matching Of Electric Power Steering System And Study Of Evaluation Technology

Vehicle with EPS needs to meet steering handiness at low speed and road clearfeeling at high speed, which the hydraulic mechanism comes short of, so EPS,which is apower steering system that adopts motor to afford assist torque controlled by ECU (ElectricControl Unit),get all-round development. Torque which is generated by motor is magnifiedthrough reducer and can be used to assist driver steer. Because EPS has great predominance,it has been gradually applied widely in a variety of vehicles, and increasingly replaces thehydraulic power steering system. Good matching technology of the EPS system has veryimportant influence for vehicle performance, and drops possibility of accident and ensuresthe safety of the passengers.This paper is aimed at analysing and discussing the matching technology of the EPSsystem. Synoptically mentioning the structure and theory of the EPS system, the advantageof the EPS system, study actuality of the matching technology, the significance of researchand the main content of this paper. Introducing the key technology of the matchingtechnology between the EPS system and the vehicle, and carrying out the matching design ofEPS key parts including power motor, reducer, torque sensor with the whole vehicle. Theinfluence of the motor and the torque sensor moment of inertia to the transient response ofthe vehicle is analysed by simulation. And the matching effect with the vehicle is analysedby simulation. Building the vehicle model, the tire model, the EPS model, the differentresistance model, the motor model. And the matching design of the assist characteristic, PIDcontrol, returnability strategy, motor compensation control, torque differential control isanalysed, and the matching effect with the vehicle is analysed by simulation. Establishingthe subjective and objective evaluation system that suits to the vehicle with EPS, anddiscussing the performance test methods and evaluation index of the evaluation item such assteering returnability test, steering wheel returnability, meanwhile, gives the objective testresults and the subjective evaluation results of the remodeled EPS test vehicle base.Summarizing the main research contents and achievements gained of this paper, in themeantime, pointing out the shortage of the paper and the further work.