Flexible PID Control Design in Assistance Condition of Automotive EPS System

Assistant control is the main work process of automotive electric power steering (EPS) system. The assistant target current was achieved based on the design of straight-line type assist characteristic. The flexible PID control is acted on the motor according to the driver´s input torque and the current vehicle speed. Using flexible PID control to track and control the motor current not only solved the contradiction between stability and accuracy of control system, but also enhances the system adaptability and robustness in the influence of uncertainty factors. The system with good real-time following characteristics in this paper can meet the motor performance requirements of EPS system, and provide a good platform for further research on control strategy and control algorithm at the same time.