Study On Active Wireless Control And Time Delay Compensation Of Structural Vibration

Structural vibration control can inhibit vibration produced by earthquake, wind or waves effectively, reduce losses from natural disasters. The vibration control system is traditionally wired control system. With the structure become increasingly complex, wired control become cost and complicated, prolong the project and is difficult to maintain and change the deployment of sensors. More importantly, the weight of cables will have bad impact on the structure itself. Therefore, the low-cost, flexible, easy wireless control has become a hot area. However, the time delay in the wireless control system causing the deterioration of control performance which need to be solved. At present, in the centralized control of huge structure, the controller need to handle enormous data in real time, faults of the controller will cause the entire system crashes. Conversely, distributed control can avoid these problems.In this paper, based on the linear quadratic Gaussian optimal control algorithm, the wireless optimal control of piezoelectric cantilever beam and the distributed wireless control of three-layer structure are studied. Firstly, based on the good simulation performance of LQG control, a wireless control system in which the WiFi nodes as the sensing unit, the dSPACE as the controller, and the sensor and control signal are all transmitted in the wireless way is designed, the wired and wireless control experiments are conducted. The results show that the arrival time of beam can be reduced by 71.33%. Secondly, a compensation scheme based on finite difference method is adopted to solve the time delay problem. The experiment of considering different delay time is conducted and the result shows that the control performance can be improved by 60.08%. In the end, the wireless distributed control of the three-story structure is designed and implemented, the simulation and experimental results show that it has a good control performance.In this study, the proposed total wireless control system can meet high sampling rate and real-time control, has good stability and control performance, demonstrates that it provide physical platform for the study of wireless control and laid a solid foundation for the practical application of wireless control.