Research On Dynamic Coupling Hysteresis Modeling And Control Method Of Piezoelectric Actuator

With the continuous development of precision manufacturing to the field of micro/nano manufacturing,micro/nano drive has become a key research field in various countries.Piezoelectric actuators have become popular in micro-nano driving due to their high frequency response,high stiffness,and high positioning accuracy.However,the hysteresis effect of piezoelectric actuators is a major challenge to the precise positioning.The hysteresis effect is exacerbated by the increased input signal frequency and dynamic force coupling in actual machining.To tackle this issue,this paper conducts an in-depth analysis of the hysteresis characteristics of dynamic coupling in piezoelectric actuators and develops a hysteresis model and controller to achieve high-precision trajectory tracking.The main research contents are as follows:(1)An improved Prandtl-Ishlinskii(PI)model is proposed to address the difficulties in describing the dynamic coupling hysteresis of piezoelectric actuators.An experimental platform is built to study the dynamic coupling hysteresis law of piezoelectric actuators and the Force-Voltage coupling PI(FVPI)model based on an improved operator is established.The accuracy of the FVPI model is verified through comparative experiments.(2)Two feedforward controllers based on the FVPI model are designed to compensate for the dynamic coupling hysteresis.The Direct Inverse(D-I)controller is designed based on the complementary relationship between the Play operator and the Stop operator,while the Analytic Inverse(A-I)controller is designed by solving the inverse model of the FVPI model.A comparison between the two controllers shows that the A-I controller has better performance in suppressing the dynamic coupling hysteresis.(3)A feedback controller based on FVPI inverse model is proposed to overcome the limitations of feedforward control,such as large steady-state error and poor antiinterference ability.A PID feedback controller’s feasibility is verified through simulation.A comparison between feedforward and feedback control shows that the feedback controller further improves the positioning accuracy of the piezoelectric actuator.