Research On Position Optimization And Active Vibration Control Of Piezoelectric Flexible Plate Actuator

With the continuous progress of science and technology,lightweight and flexible intelligent structures have been widely used in different fields.Due to the low damping and stiffness of flexible structures themselves,it is easy to produce low-frequency vibration and slow vibration attenuation when subjected to external disturbance,which has adverse effects on high-precision operation scenarios such as aerospace.Vibration can cause fatigue damage of structure and shorten service life.How to solve the vibration problem of flexible structure has attracted great attention of scholars.Active control has good control effect on the low frequency vibration of flexible structure,and has good flexibility and adaptability to the changing external disturbance.However,there are many factors that affect the active vibration control effect,such as the position of the actuator,the vibration control method and the hysteresis effect of piezoelectric materials.In order to improve the active vibration control effect of flexible structure,this paper takes a flexible cantilever plate as the research object to carry out the optimization design of active vibration control of structure.The research contents are as follows:(1)The properties of piezoelectric materials are analyzed.The finite element method and Hamilton principle were used to establish the dynamic model of piezoelectric flexible plate,and the correctness of the mathematical model was verified by ANSYS software simulation.(2)The objective function of actuator position optimization is established according to the system controllable Gramian matrix.The proposed improved particle swarm optimization algorithm(BAS-PSO)was used to optimize the position of the actuator of the piezoelectric flexible plate,and the position optimization results were obtained under nine working conditions with 1-9 actuators respectively.(3)Aiming at the nonlinear hysteresis of piezoelectric materials,the nonlinear hysteresis model of piezoelectric actuators was established based on the P-I model,and the parameters of the hysteresis model were identified by BAS-PSO algorithm.A feedforward compensator based on the P-I inverse model was designed,and the effectiveness of the designed feedforward compensator was verified by signal tracking simulation.(4)The active vibration control of piezoelectric flexible plate is simulated by MATLAB software combined with LQR optimal control algorithm.The simulation results verify that the designed control system can significantly reduce the vibration of flexible plate.In the process of vibration control,the hysteresis compensation of the piezoelectric actuator by optimizing the actuator position and adding the feedforward compensator can effectively improve the vibration control effect.