压电陶瓷叠层作动器迟滞蠕变非线性自适应混合补偿控制方法

The hysteresis and creep nonlinear characteristics of piezoelectric actuators seriously affect the stability of the control system and the accuracy of dynamic tracking. To mitigate hysteresis and creep effects, this paper presents an adaptive hybrid compensation control method that is a feedforward-feedback control method combining hysteresis-creep feedforward compensator with adaptive filter feedback control. Based on the Modified Prandtl-Ishlinskii (MPI) model, the hysteresis and creep nonlinear characteristics of piezoelectric actuators are refined and the inverse hysteresis-creep compensator is established for feedforward compensation. Based on the errors of the feedforward compensation, an adaptive filter feedback controller is adopted to adjust the input signal in real time to achieve an accurate compensation control of hysteresis nonlinearity and lg(t)-type creep characteristics of the piezoelectric ceramic actuator. The numerical simulation and experimental results show that the error of the adaptive hybrid compensation control of piezoelectric actuators is reduced effectively compared with the traditional feedforward compensation. It is shown that the proposed adaptive feedforward-feedback control scheme can largely improve the accuracy and adaptation of hysteretic compensation dynamic tracking.