Research On Active Vibration Control Algorithm Based On Piezoelectric Intelligent Structure

Nowadays navigation system,test system and many other structures on the accuracy requirements are getting higher and higher,but the environment or internal disturbance caused by structural vibration is inevitable.Vibration often leads to structural performance degradation and even structural damage,for this study to solve the problem of structural vibration in the actual project is necessary.Piezoelectric intelligent structure as a new active structure,because of its unique piezoelectric effect,good electromechanical coupling,etc.are widely used in vibration control system.Piezoelectric intelligent structure in the practical application by the external and internal multiple uncertain perturbation,so the search for simple and real-time active vibration active control method has become an urgent need to study one of the topics.In this paper,the active vibration control algorithm based on perturbation observation and feedback is studied in order to improve the active control ability of the piezoelectric intelligent structure under complex disturbance.Based on the actual configuration of the number of sensors and actuators in the piezoelectric intelligent structure,the system is divided into single input single output type,multiple input multiple output type and multiple input single output type.The state space equation is established respectively.Then,based on the problem of retardation of feedback control and difficult modeling of perturbation signal,a composite control algorithm based on disturbance observation and PID control is designed.The simulation results of vibration control under different models show that:(1)The composite algorithm has a certain applicability in different models.Under the excitation of external disturbance,the effect of compound controller on structural vibration can reach about70%,1.2-2 times better than that of single feedback controller.(2)The performance of the control algorithm is related to the structural model.When the multi-mode control of the structure is adopted,the independent modal control of the composite control algorithm canavoid the coupling effect between the modalities and has some excellent.(3)the system for a single input,the use of two actuators control effect than the use of an actuator is better than twice the effect.Finally,the composite algorithm is improved by considering the existence of sensor measurement noise and delay quantity.Simulation results show:(1)composite controller for high frequency measurement noise does not have the inhibitory effect.The improved controller can reduce the impact of high frequency noise on the system by more than 40 dB.(2)Under the compound control algorithm,the system delay is easy to cause the initial amplitude of the response to increase,and the delay time of the single oscillation period is more than 40%.An improved algorithm with adaptive Smith predictors can effectively compensate for system delays and allow for the existence of estimated deviations.The composite control algorithm designed in this paper and its improved compensation structure are simple and applicable.Under the condition that the structural model and the structure may be considered,the simulation results can achieve satisfactory results,which can guide the actual vibration active control.