压电耦合板主动控制及稳定性分析

ACTIVE CONTROL AND STABILITY ANALYSIS OF COUPLED ELASTIC/PIEZOELECTRIC PLATE

本文研究压电耦合板的主动控制及稳定性。压电耦合板在采用作为传感器和驱动器的压电片之间的速度负反馈时 ,能增大系统的阻尼性能。本文以闭环控制系统方法的特征值分析为基础 ,分析研究了其稳定性。研究表明主动控制在增加系统阻尼性能的同时 ,亦可能导致系统出现不稳定现象。文中指出当仅有对点之间的负反馈时 ,系统是渐近稳定的 ;当负反馈增益矩阵呈非对称或对称但非正定时 ,系统可能出现非稳定。文中以算例进一步给予证实。

WT5BZ]A study on active control and stability analysis of coupled elastic/piezoelectric plate is presented in the paper.Active control of such a plate does increase the damping property of system through negative feedback between two piezoelectric pieces as transducer and actuator respectively.Based on analysis of characteristic equation of the closed_loop control system,it is shown that such an active control may increase damping property of the system,meanwhile it may result in instability of the system.It is stable when the feedback only occurs between one pair of corresponding transducer and actuator,but it may be unstable when there exist feedbacks among transducers and actuators,mainly depending on the property of the gain matrix of feedback.If the matrix is symmetric and definitely positive,the system is stable.Further verification is given by some numerical examples.