A Wiener Model Identification for Creep and Vibration Linear and Hysteresis Nonlinear Dynamics of Piezoelectric Actuator

The piezoelectric actuator exhibits both linear dynamics of creep and vibration and nonlinear dynamics of hysteresis. The model identification from experiments can compensate uncertainties in the model and get a satisfactory model for the control. Block-oriented nonlinear model is suitable for modeling this kind of linear and nonlinear hybrid dynamics. In this study, a Wiener model identification method for the piezoelectric actuator is proposed to model the linear and nonlinear dynamics together from the data. The model is called two-linear(linear+linear)-nonlinear (TLN) Wiener model, where two additive linear dynamic models are used to identify the creep and vibration dynamics, and a nonlinear dynamic model is followed to identify the hysteresis nonlinear features. The TLN-Wiener model is parameterized using Laguerre functions and Prandtl-Ishlinskii (PI) model, and the model identification algorithm is proposed. The experiments on piezoelectric actuators show that the TLN-Wiener model identification method can model the creep, vibration and hysteresis dynamics. The method is applicable to model the rate-dependency dynamics of the piezoelectric actuator.