Modeling of Electric Power Steering System and Research on Control Strategy

Abstract

The advantages of Electric Powered Steering System are summarized and the model of EPS is developed. On the basis of the model, the different control effects of proportion control and proportion-plus-derivative control are compared. The simulation results show that proportion control with higher gain will cause the vibration of the steering wheel, at the same time, will allow high frequency disturbance to transmit easily to the steering wheel and create harsh steering feel. Proportion-plus-derivative control introduces the derivative function and increases the damping of EPS system. The system bandwidth can be adjusted by changing the derivative coefficient, so the contradiction among the steering agility, the vibration of the steering wheel and restraining the high frequency disturbance from road can be solved successfully.