Research On Piezoelectric Stiffened Panel Structure Time-delay Active Vibration Control

Stiffened panel structure can improve the reliability, durability and efficiency of the plate, and also can reduce the structure weight. The stiffened panel structure has been widely used in aerospace, machinery, ships, cars and buildings, and many other fields. So design effective control method to control vibration of stiffened panel is a hot study issue. Because of asymmetric ribs and other factors may cause non-linear enhancement, so the nonlinear factors should be think in the control process. In the control, it’s often exist different degrees of time delay, which leading to a poor control effect. In order to improve the control effect of the time delay system, there need to a time-delay compensation for the control.Using the piezoelectric smart stiffened panel as the research object, and the piezoelectric as sensor and actuator, carry out on the stiffened panel vibration modal identification and vibration active control and time delay compensation theoretical and experiment research based on the MCS algorithm. The main contents are as follows:The second chapter expounds the working principle of the piezoelectric element and the basic theory of piezoelectric equation, and according to the basic theory, the mechanics equations and state space equations of stiffened panel was developed. ANSYS software is used to stiffened panel 3 d model for modal analysis, and obtain the former second order modal frequency. Using Beijing pop experiment platform analysis vibration modal of stiffened panel by frequency sweep motivation method experiment. The theoretical and experimental method is used to identify the modal parameters of stiffened panel, prepare for below of the MCS control simulation and experiment.The third chapter briefly describes the basic principle of the MCS algorithm, and deduced parameters mathematical expression of the algorithm. According to the modal identification of parameters in the second chapter, then use the Matlab-Simulink software to write the MCS algorithm program, and proceed the stiffened panel vibration control simulation study.The fourth chapter first carry on the simple introduction of time delay, and analyses the reason of delay and the impact on the system, and then briefly describes the basic principle of Smith predictor time-delay compensation, and build a time-delay compensation factor which according to the principle of the time-delay compensation is added to the standard MCS algorithm, to form a new MCS algorithm with delay compensation function, and the algorithm stability proof. Finally, use Matlab-Simulink software to have a simulation for the new algorithm, the result shows that adding the time delay compensation MCS algorithm has a good effect of time-delay vibration control.The fifth chapter through the analysis Smith predictor weak robustness and defects of delay compensation algorithm, put forward to using adaptive Smith predictor add to the MCS algorithm. Combined with the lyapunov second method to design the adaptive factor, and construct the MCS algorithm of time delay compensation. Using Lissajou measured the delay time of control system. Then write the Lab VIEW program of MCS algorithm, and through the CRIO real-time control platform do active vibration control experiment, the experiment result shows that the adaptive time delay compensation MCS algorithm can effectively reduce the delay time measurement error effect on the control.