Adaptive Active Control Of Vibration And Noise Of Piezoelectric Elastic Beam-plate Structure

The problem of structural vibration and noise has always been an important research topic in the field of engineering control.With the continuous development of space technology,the excitation environment of space structures is becoming more and more complex,resulting in more prominent vibration and noise problems of structures.Smart material structure is an emerging material structure developed in recent years.Through the design of smart material structure and active control algorithm,the vibration control of the structure in the low frequency band can be realized.Therefore,it is of great significance to carry out research on active vibration control of smart material structure.In this paper,based on MFC piezoelectric fiber composite material,a piezoelectric intelligent beam-plate structure is designed,and the active control method of adaptive filtering is used to carry out research work on the vibration and noise active control of piezoelectric intelligent beam-plate structure.The specific research contents are as follows:Firstly,based on the MFC piezoelectric fiber composite material,a piezoelectric elastic beam and plate structure are designed.Considering the electromechanical coupling relationship of the MFC piezoelectric smart material,based on the Euler-Bernoulli beam model,the piezoelectric smart beam is derived.The sensing/actuating equation of the structure is established,and the dynamic analysis model of the piezoelectric smart beam structure is established.The velocity and displacement state space vectors are introduced,and the state space governing equation of the piezoelectric smart beam structure is further obtained.On this basis,considering the deformation theory of the thin plate,the dynamic analysis model of the piezoelectric intelligent plate structure is established,the sensing/actuating equation of the piezoelectric intelligent plate structure is deduced,and the spatial state control of the piezoelectric intelligent plate structure is given.equation.It provides a theoretical analysis basis for the subsequent establishment of active vibration control of piezoelectric smart beam-plate structures.Secondly,the research on the active vibration control of piezoelectric cantilever beam structure is carried out,and the single-channel and multi-channel adaptive feedforward filtering least-mean-square algorithm of piezoelectric smart beam structure is deduced,and the single-channel and multi-channel vibration active control of piezoelectric smart sheet structure is established.Control the simulation system,analyze and discuss the influence of controller parameters on the active control performance of the adaptive simulation system.Study the active vibration control of piezoelectric smart beam structures under the action of various forms of excitation signals,and build an adaptive active control closed-loop experimental platform for piezoelectric cantilever beam structures to test the experimental effects of active control of smart beam structures under different frequency sinusoidal signal excitations,to verify the theoretical simulation results proposed in this paper.The experimental results show that for the single-channel vibration active control test of the piezoelectric cantilever beam structure with different frequencies of sinusoidal excitation within 50 Hz,the controller can achieve a good control effect,which verifies the effectiveness of the vibration control method proposed in this paper.Then,the research on the active vibration control of the piezoelectric thin plate structure is carried out,the vibration modal characteristics of the four-sided simply supported thin plate are calculated,the placement position of the piezoelectric sheet is analyzed and determined,and the vibration active control of the piezoelectric intelligent thin plate structure based on the adaptive control algorithm is established.Control the simulation system,analyze and discuss the influence of controller parameters on the active control performance of the piezoelectric intelligent thin plate simulation system.The active vibration control of the piezoelectric smart sheet structure under the combined excitation of different frequencies and the narrow-band random excitation is further discussed.In addition,an active control closed-loop experimental platform for piezoelectric thin-plate structure was built to test the vibration control experimental results of the intelligent thin-plate structure under the action of different frequencies and their combined sinusoidal signals,and to verify the calculation results of the proposed active control simulation system.The experimental results show that for the low frequency within 30 Hz and its combined excitation signal,the piezoelectric intelligent thin plate controller can achieve better control effect,and can greatly reduce the vibration response of the thin plate structure at the sensor position.Finally,the active control of vibration radiation noise of piezoelectric thin plate structure is studied.The state equation of the elastic thin plate cavity coupling system is established,and the cavity acoustic potential energy is used as the objective function to construct an adaptive feedforward filtering algorithm for active control of the radiated noise of the thin plate structure,and the active control of the controller parameters for the structural vibration radiated noise is analyzed and discussed performance impact.At the same time,under the action of excitation signals of different frequencies,the active control performance of the vibration radiation noise of the thin plate structure is analyzed.The research results show that when the convergence factor or filter length is increased,the convergence speed of the controller can be significantly accelerated and the stabilization time of the control system can be shortened.The adaptive feedforward filtering algorithm can effectively control the vibration radiation noise of the thin plate structure.