Modeling and Tracking Control of a Magnetostrictive Actuator

Due to the rate-dependent hysteresis nonlinearity in the magnetostrictive actuator, the tracking control accuracy is limited. This paper presents a new method of modeling the hysteresis in the actuator and a dSPACE-based tracking control approach. The relationship between input and output of the actuator is approximately described by a dynamic differential equation with two rate-dependent coefficients. Each coefficient is expressed as a polynomial of frequency. For a fixed frequency, the coefficients will be able to be estimated by approximating the experimental data of the output of the magnetostrictive actuator. Based on this model, a quasi-PID controller is designed. In the space of the coefficients and frequency, the stable domain of the close-loop system with hysteresis is analyzed. By the numerical simulations and experiments of tracking sinusoidal wave with frequency ranging 1 Hz to 100 Hz, the results show that the proposed method is efficient