Linearization of Stack Piezoelectric Ceramic Actuators Based on Bouc-Wen Model

Abstract

In this article, in order to linearize the hysteresis behavior of stack piezoelectric ceramic actuators (SPCAs), the feedforward linearization method based on the Bouc-Wen model and the hybrid linearization method combining the feedforward method and PI feedback loop are proposed and explored. The rapid control prototypes of the linearization controllers for the SPCA are established and tested. The research results show that both the feedforward and hybrid linearization methods can linearize the hysteresis behavior and the SPCAs with linearization controllers can be regarded as linear actuators. However, the linearization accuracy using the feedforward method is confined by the modeling error of the Bouc-Wen model. Although the proposed hybrid method combining the feedforward method and the PI feedback loop can reach higher linearization accuracy than that with the feedforward method, the hybrid method will result in high frequency components in the additional voltage, which will have a serious impact on the lifespan of the controlled SPCA. Utilizing the linearization methods proposed in this article, the open-loop and closed-loop controls for the tip displacement of a piezoelectric-driven microgripper are realized, which indicates that the proposed linearization methods can simplify the control of SPCAs and SPCA-based systems with high accuracy.