Fault Tolerant Control Of Complex Networks And Application

Complex networks are ubiquitously found in nature and the modern world as many real world systems can be modeled by complex networks.In the past few decades,synchronization and control problems of complex networks are being extensively studied in various fields of science and engineering.On the other hand,due to the complexity of the complex network system,dependability is as important as performances.Faults may lead to undesired reactions in the systems,ranging from performance degradation to instability,and fault tolerant control(FTC)aims at guaranteeing the system goal to be achieved in spite of faults.Thus,it is of great significance that we apply FTC to complex network systems.However,the FTC of complex network systems is yet to be investigated,as there is no other existing literature regarding the FTC issue of complex network systems.The thesis is derived from key project of Natural science of Jiangsu Province.This paper studies the FTC of unreconfigurable nonlinear complex network systems and reconfigurable nonlinear complex network systems respectively.First,this paper introduces the current research situation of complex network systems and FTC,including the FTC of other similar network systems such as neutral network systems.Then,the FTC ideas and methods often used in network systems are emphatically introduced in this paper,based on which we propose the FTC strategy of complex network systems.The main contributions are listed as follows:(1)An integrated fault estimation and accommodation method for a class of unreconfigurable nonlinear complex network systems is proposed.A set of novel distributed adaptive estimators are designed to simultaneously estimate the unknown state and fault(s)information,based on which a decentralized fault accommodation scheme is further constructed to stabilize the complex network system.An example of a network consisting of three one-link manipulators is presented to demonstrate the effectiveness of our proposed method.(2)A fault tolerant cooperative control strategy for a class of reconfigurable complex network systems is proposed.The general neighboring rule-based linear cooperative protocol is developed and a sufficient synchronization condition is derived.Moreover,it is shown that the target point is still reached with the proposed fault tolerant cooperative control method when fault occurs.An example of a complex consisting of four one-link manipulators is presented to demonstrate the effectiveness of our proposed method.