Optimized PID tracking controller for piezoelectric hysteretic actuator model

摘要

World Smart materials such as piezoelectric actuators possess useful properties especially in the field of micropositioning. Tracking control accuracy of these systems is limited due to its inherent hysteresis nonlinearity. Designing a precise tracking controller for a piezoelectric actuator with hysteresis nonlinearity is our purpose in this paper. A Bouc-Wen model is used to describe the hysteresis behavior of the actuator. Multi-parameter-optimization techniques are used twice in this paper; first for obtaining a linear model equivalent to the overall nonlinear actuator model, and second for tuning the gains of the PID controller for suppressing the tracking errors and hence getting precision tracking. Several advantages are gained on solving parameter optimization problems using computers; neither reliance on intuition nor experience in control is required, in addition to producing a satisfactory system response with optimal use of effort and time, high convergence speed, high approximation accuracy, high efficiency, and suitability for many kinds of goal functions. Simulation results performed on the nonlinear system verify the efficiency of the proposed method.%piezoelectric actuator; hysteresis; Bouc-Wen model; parameter optimization; parameter estimation