Abstract:The output displacement of the piezoelectric stack actuator(PSA) exhibits hysteresis nonlinear characteristics.To achieve further research and control,a modeling of the reliable hysteresis nonlinearity is essential,especially in the fields of precision control and electrohydraulic actuator and etc. Firstly, a quasistatic model is established by using the modified asymmetric BoucWen model according to the static characteristic of PSA in this paper.Then,the output force is divided into the linear portion and the lag portion to descript the dynamic displacement output features,and a hysteresis nonlinear dynamic model of the PSA is established according to the system kinetic equation. Finally,the parameter identification,model simulation and experimental study have been carried out.The results show that the model can accurately descript and predict the dynamic characteristics of the PSA at the frequency range of 400 Hz.