ACTIVE CONTROL OF PIEZOELECTRIC INTELLIGENT ANNULAR PLATES 1)
压电智能环形板的主动控制

In recent years, piezoelectric intelligent materials have been widely used as sensors and actuators in structural shape control, vibration control, etc. It has wide and active field in research and application. The structures with large sized, low stiffness and flexibility are important characteristics in space flight industry. But, because modal damping of the structure is small, when an outside shock force or interference force acts to the structure, it will cause much large deformation and vibration of the structure. If this vibration is not controlled, it will last long time. After piezoelectric material is utilized, it may easily be applied to accurate monitor measurement of flexible structure. Then the structure can be controlled effectively . Crawley and Im successfully studied the action between piezoelectric piece and beam. Wang and Roger studied equivalent action of piezoelectric piece on lamination plate, and gave location function of the strain which is generated by piezoelectric effect. It is simple and direct in research to piezoelectric structures. And it may be applied to the active control of the deformation and vibration of plate. Axial symmetric vibration control of intelligent annular plate with distributed piezoelectric sensors and actuators are studied. By using the equivalent action of piezoelectric actuators, control equation of vibration and sensor equation on the intelligent annular plate are obtained. And by using the separate variables method and control model between charge on sensors and voltage acting on actuators, the solution of vibration equation is obtained. Active control system of the structure can be realized. Some examples are calculated. The results show that the closer piezoelectric components are positioned, the better control effect will be.