Research On EPS Oriented System Modeling And Co-simulation

Steering system is one of the major subsystems of vehicles, the performance directly related to the comfort and safety of vehicles. With people's demands of vehicle comfort and safety, a growing number of vehicles use the electric power steering system(EPS) which has the merit of environmental protection, energy saving, safe and comfortable. The rapid development of computer technology, mechanical software ADAMS and scientific software MATLAB provides a more convenient and effective platform for the study of electric power steering system.In virtue of the Zhejiang province key project 'C-EPS research', based on the analysis of EPS, a whole automotive model was built by software ADAMS and the control system model was established through software MATLAB. The co-simulation were carried out by using the software of ADAMS and MATLAB to connect the electric power steering control system model with the whole automotive model.The following points are finished in this thesis:1) The thesis introduces the development of EPS and its features including function, types and advantages, and summarizes the research status about the EPS. The research content is confirmed based on the particular defects of the EPS.2) Based on the multi-body dynamics theory, using the ADAMS software, built the vehicle model including the front and rear suspension system, the steering system, tires system and power train and brake system. Compared with the real experiment results, the model is proved to be reasonable and applicable.3) The dynamic model, assist characteristic , assist control strategy of EPS were analyzed and the EPS control system model was built in MATLAB environment, and the simulation result shows that the design is effective.4) Joint simulation of MATLAB and ADAMS was studied by using the respective advantages of the software ADAMS and MATLAB, the vehicle model will be based on ADAMS and the EPS-based control system MATALAB model for handling stability simulation to study the manipulation of stability EPS Of the impact.5) The impacts of the parameters of EPS on handling stability were analyzed from the aspects of steering sensitivity and the driver's road feel in this thesis. And its results have reference value for the determination of the parameters of EPS.This thesis makes analysis and simulation on the EPS. And its results are helpful and have reference value for the EPS product research.