Control System Study On Electric Power Steering

Along with the development of electronics technology and motor control technology , Electronic Power Steering (EPS) is the trend to replace Hydraulic Power Steering (HPS). It has not only the advantage of smaller volume, lighter weight, simpler structure , easier installation and maintenance, lower consumption, better environmental protection, but also can improve the dynamic and static performance of the automobile, improve the driver's coziness and security, enable it fit for many kinds of vehicle such as car, truck etc. At present, the external EPS has been more riplely, a lot of automobile has adopted this kind of steering system. But its study is still in primary stage in our country, and only personal mobile has adopted it. Therefore, it is of great importance to study and develop this kind of steering system.Through analysis of key technology problem of EPS currently, the aim is to develop control system, to research to electronic power steering systematically. This dissertation finished main research contents on these following aspects:This text has described electronic power steering system of structure type, operation principle, constitution and performance characteristic, system requirement of key position of system, which have offered the basis for systematic development and selection of the part.Hardware circuits of electric control unit are developed and designed in the paper, finished design of circuit of control system as the core of LPC2119 chip, which concluded circuits of signal acquisition and disposal, motor drive control and protection,clutch drive, relay control, system power etc, which have offered ensure for development of system.This paper has researched motor power characteristic, adopted Fuzzy Neuro Network Controller (FNN) to confirm target current and utilized PID controller to tail after target current. educed power characteristic through fuzzy reasoning and neuro network training, realizes power characteristic in case of random velocity.A design model of EPS testing equipment was presented, which provided academic basis for further research on EPS bench experiment.