Non-symmetrical Bouc-Wen model for piezoelectric ceramic actuators

The existing Bouc-Wen models for piezoelectric ceramic actuators (PCAs) possess the symmetrical characteristic of the hysteretic component and can be categorized as symmetrical Bouc-Wen models. When modeling PCAs with non-symmetrical hysteresis by a symmetrical Bouc-Wen model, large modeling errors will occur. In this paper, a non-symmetrical Bouc-Wen hysteresis operator for modeling the non-symmetrical hysteresis of PCAs is established by introducing a non-symmetrical formula into the Bouc-Wen hysteresis operator. Accordingly, a non-symmetrical Bouc-Wen model for PCAs is proposed and established by modeling the non-symmetrical hysteresis component of PCAs with the non-symmetrical Bouc-Wen hysteresis operator. A corresponding parameter identification method, which can identify the parameters by obtaining analytical solutions with a set of input-output experimental data to and from a PCA with an applied periodic voltage under the zero initial condition, is established. In the parameter identification, the least-squares method is used to reduce external random disturbances. The performance of the non-symmetrical Bouc-Wen model with the corresponding parameter identification method is experimentally verified by the established experimental setup. The research results show that the non-symmetrical Bouc-Wen model can simulate the PCA with the non-symmetrical hysteresis more accurately than the symmetrical Bouc-Wen models, and the modeling errors are decreased by about 30%. In addition, the established parameter identification method can be used to identify the parameters of the non-symmetrical and symmetrical Bouc-Wen models effectively and quickly. (C) 2012 Elsevier B.V. All rights reserved.