The Dynamic Analysis And Control Strategy Research For Automobile Electric Power Steering System

As a new kind of car power steering system, Electric Power Steering(EPS) system canimprove active safety, save fuel and be good for the environment. It is a new technology,which is gripping modern automobile development theme:safe,energy-saving,environmental protection. A lot of foreign and domestic car companies and designers are paying more and more attention to EPS. Meanwhile, with the development of computer technology, all sorts of system simulation software of the simulation accuracy and simulation performance are getting better and better. It also provides favorable conditions for electric power steering system researches.In this paper, electric power steering system research purposes and meanings aredescribed firstly,then electric power steering system's main structure,working principle and types are introduced.The research situation at home and abroad of electric power steering system are also studied.Meanwhile,the multibody system dynamics theory is introduced, the mechanical system dynamics analysis software ADAMS(short for Automatic Dynamic Analysis of Mechanical Systems)is introduced especially.Full Vehicle dynamical model is built through ADAMS/Car.Referring to the controllability and stability test procedure for automobiles, pylon course slalom test and steering efforts test procedure are built for verify the validity of the model.In addition, the assist characteristic of electric power steering system are analyzed.An assist characteristic curve about the speed is established.The assist characteristic control model is buidt in MATLAB/Simulink. The electric power steering system dynamical modeland motor control model are also established for the co_simulation later.Finally, the methods and steps of the co_simulation are introduced.The control strategy is studied.The PID control system is established for the ADAMS/Car and MATLAB/Simulink co_simulation. The accuracy of the models and the feasibility of the co_simulation are proved though simulation test.The purpose is to lay the foundation for the simulation experiment in future.