Control Method of Giant Magnetostrictive Precise Actuator Based on the Preisach Hysteresis Theory

Aiming to the effect of hysteresis characteristics of giant magnetostrictive materials on the giant magnetostrictive actuator, the actuator’s model is divided into four separate segments. Then, based on the Preisach theory, a model which can describe hysteresis characteristics for the actuator is established. Based on this, feedforward is combined with feedback, and a PID closed-loop feedback control system which is with feedforward compensation is designed. On one hand, the nonlinear hysteresis of actuator’s output is compensated by the feedforward compensation method. On the other hand, errors resulted from the inverse process of compensation and random interference are eliminated by PID controller. Experimental results show that, the adjusting time of actuator output displacement reaching a steady state and the overshoot are about 5ms and 7.5% respectively. Therefore, the control method designed in the paper can realize the accurate and effective controlling for giant magnetostrictive actuator.