The operation characteristic and control system design of automotive EPS motor is one of the key technologies to satisfy steering performance and to realize system’s reliable operation.The structure

working principle and the operation characteristics of EPS motor were studied.The corresponding control strategy and power drive circuit were designed.The test bed and steering handiness test were designed.The test results show that not only realize the EPS’power assist effect but also validate the validity of motor power drive circuit design.It has practical engineering significance to guide the design of EPS system and to improve the operation efficiency and to optimize the operation characteristic.