Analysis For Decoupled Problem Of Decentralized Vibration Control

With the rapid development of aviation,large-scale flexible structures such as largearea solar battery arrays and large-area radar antennas are increasingly used in spacecraft.Due to the particularity of the environment,it is difficult for these large structures to avoid the vibration which affects the normal operation of the spacecrafts.Therefore,the spacecraft must not only have high attitude stability and pointing accuracy,but also be able to quickly suppress the vibration of large flexible structures caused by maneuver interference.However,the traditional control methods are centralized control,which requires complete information.For a large flexible structure with a large volume and a complex structure on a spacecraft,the traditional "centralized" control cannot be realized on the spacecraft.Therefore,it is of great significance and value to study the decentralized vibration control.The decentralized vibration control attempts to avoid the "centrality" of traditional control theory by dividing the control problem of a large system into the output feedback problems of several subsystems.This method effectively reduces the size and complexity of the system,and the traditional control methods can continue to be used on the subsystems.However,the current distributed vibration control methods,even the distributed vibration control method recently studied,have coupling between subsystems.If a state of subsystem changes after being controlled,the change will also affect the state and control of other subsystems,which makes it difficult to control.Moreover,information transmission between subsystems is required,while spacecraft has strict requirements on quality,number and installation location of sensors.If coupling between subsystems can be solved,it is bound to reduce the calculateon difficulty and the number of sensors.At the same time,the parallel control between subsystems can also improve the convergence speed of the vibration system.The above is the main purpose of this paper.The target of control is still to make the entire large system stable.The main contributions of this article are:1)By decomposing the vibration control system based on physical coordinates and modal coordinates along the boundries of physical subsystems and the relevance of information,the problem of state coupling and control coupling between subsystems can be solved through reasonable decomposition,reordering,and composition of matrix.2)The control methods such as dynamic compensation and local state feedback are applied to each subsystem,then we can study the decoupled theory of subsystems with physical and modal parameters,which solves the main contradiction that the information structure is restricted and cannot obtain all the required information.By using these local and incomplete information,we can coordinate the decentralized controllers to achieve the target of the control of the entire system.3)Starting with the basic vibration model,the finite element softwares ABAQUS and ANSYS are used to obtain the required parameters of model,then the correctness of the decoupled decentralized vibration control method in this paper was verified by using MATLAB platform,and the method in this paper is compared with the centralized control and the current distributed vibration control method.4)Modeling and simulating the vibration control system of the solar panel of satellite,and demonstrating the correctness and practicability of decoupled decentralized control with dynamic compensation and with local state feedback respectively.