Research On Stability Analysis And Fault-tolerant Control Of Networked Control Systems

Networked Control Systems(NCSs)are closed-loop distributed control systems.It connects sensors,controllers and actuators distributed on different sites by the network.The networked control systems has the advantages of easy installation and maintenance,self-weight reduction and lower running cost because of the introduction of the network,so that the application of the networked control systems becomes more extensive and convenient.But at the same time,the networked control systems will inevitably have the following issues like time delay,data packet dropout,variable period and other issues which will seriously damage the performance of the networked control systems.This paper discusses the modeling,analyzes the stability and researches the guaranteed cost control and fault-tolerant control of the networked control systems which is under variable-period sampling.And the main work is as follows:1.Aiming at a kind of networked control systems with time delay,external disturbance and time-varying sampling period,a discrete mathematical model is established by discretizing the linearly controlled objects.In this process,the uncertainty of the sampling period is transformed into the uncertainty of the parameters.2.On the basis of the discrete mathematical model,the Lyapunov stability theorem and the LMI method are used to deduce the sufficient conditions for the system to maintain stability and give the calculation method of the relevant control law.3.For the variable sampling period networked control systems with external disturbance,the LMI method is used to analyze the guaranteed cost control.And the design method of the guaranteed performance controller of the system is deduced by using the inequality amplification technique and the convex optimization method.4.The fault-tolerant control of networked control systems is studied.While the networked control systems has actuator failure,the existence condition and design method of the fault-tolerant control law are given by using the Lyapunov stability theorem.In the process,the actuator failure is described by a numerical matrix.