A Study on the Control Strategy of Power Characteristics of Recirculating Ball-Type Electrical Power Steering System

Studies the power control strategy of the electrical power steering(EPS ) system in a pure electric power bus. The recirculating ball-type EPS system is designed by optimum design and its dynamic model established. Due to the demand of the robust stability and dynamic characteristics, the double-layer control strategy is adopted, and consists of the mixed H₂/H_∞ controller for determining the current and the fuzzy PID controller for tracking the current. Simulation results showed that the H₂/H_∞ controller could attenuate the road disturbances and provide satisfactory road feeling for drivers, and the fuzzy PID controller could track the motor current well and provide the ideal assisted characteristics for the drivers.