Investigation On Self-sensing Vibration Suppression Using Piezoelectric Mirror Circuits

Unnecessary structural vibration will accelerate its fatigue damage which reduce its service performance and work life.When push comes to shove,it will result in serious accidents.It is more and more important to solve the damage which is caused by vibration in structure effectively.Therefore,structural vibration suppression has always been a hot topic and an urgent problem for researchers.Taking cantilever beam structure as the research object and piezoelectric material as the self-sensing actuator,this work designs cantilever beam vibration suppression system.The coupling signal is separated by mirror circuit and the control strategy is modern classical PID algorithm.Study on vibration suppression of piezoelectric cantilever composite structure from two aspects.On the one hand is theoretical derivation,on the other is experimental verification.The main work is as follows:Firstly,the positive and negative piezoelectric effects of piezoelectric ceramics are briefly described.It also is briefly elaborated that four different types of piezoelectric equations and four common piezoelectric material boundary conditions.These lay the foundation for the theoretical analysis of piezoelectric self-sensing actuator.Then,the modeling process and mechanical analysis of the cantilever beam are carried out.Vibration mode functions for beams and the theoretical formula of natural frequency are helpful to analyze the static and dynamic characteristics of cantilever beam.On this basis,COMSOL simulation software is used to model the cantilever beam,and the simulation analysis is carried out to verify the correctness of the theoretical analysis results.Secondly,according to the transfer matrix of piezoelectric transducer,the feasibility of piezoelectric ceramic as both sensor and actuator is analyzed theoretically.Based on the investigation of the decoupling methods of piezoelectric self-sensing actuators at home and abroad,a mirror circuit based on piezoelectric charge driver is designed as the decoupling circuit.PID algorithm control strategy is used to demodulate the vibration sensitive signal of the structure,and the sensing signal is fed back to the actuator to drive the piezoelectric material.According to the vibration state,make the corresponding motion to restrain the vibration of the structure.The vibration suppression of the structure is realized through the above process.Finally,based on the above theoretical and simulation analysis,the cantilever beam is taken as the research object and a piezoelectric self-sensing vibration suppression system is built.By simulating the continuous disturbance of the external environment and changing the experimental parameter,the validity and adaptability of the system are verified.Experimental results show that the first mode of vibration is suppressed,and the amplitude of the vibration is actively dampened by a factor exceeding 96.4%.Moreover,the frequency sweep experiments demonstrate that with the PID feedback control circuit connected to the piezoelectric cantilever beam,the Q value of the system is greatly reduced,and the loss factor is increased from 0.053 to 0.288.The vibration control of cantilever beam is realized successfully.