Research On Stability Analysis And Control Method Of Networked Control Systems With Uncertain Time-delay

With the rapid development of science and technology,computer and network communication technologies have made great progress.In order to meet the increasingly updated requirements of control systems,Networked Control Systems(NCSs)is emerge.NCSs are products that combine traditional control systems with network communication technologies.System wiring is simplified,installation and maintenance.It's convenient.meanwhile resource sharing and remote control can be realized among different users,which effectively reduces control costs and improves work efficiency.However,the introduction of the network also brings problems such as network induced delay,packet loss,sampling period change,etc.,which will affect the performance of the control system and reduce its stability,thus increasing the difficulty of system modeling design and analysis.Based on Lyapunov stability theory,this paper studies the system stability,non-fragile guaranteed cost control,H_? control and fault-tolerant control under actuator faults for networked control systems with uncertain time delays.For systems with non-zero delay and uncertainty,this paper uses a more general feedback controller to define the quadratic integral term using the integral inequality method.Based on this,the stability analysis of the system is carried out and the robust stability conditions of the system are derived.The non-fragile guaranteed cost control research is carried out on a class of networked control systems with time-varying delays.The uncertainty of the sampling period is modeled as the uncertain parameter of the system and a dynamic interval system is obtained.Based on this,the relevant reference is used.Prove the stability of the system and give the design method of the non-fragile guaranteed performance controller.The H_? control research of a class of variable sampling period systems with time-varying delays is carried out.The Bernoulli distribution sequence is used to describe the packet loss,and the Lyapunov function is constructed to analyze its stability.Finally,the controller design method is given and the system meets certain performance indicators.The fault-tolerant control of the system with actuator failure is studied.The nonlinear part of the system is modeled as an uncertain nonlinear term satisfying the Lipschitz condition.On this basis,the failure of the actuator is considered,and the Lyapunov stability is utilized.The theorem and LMI method study the non-fragile guaranteed cost control of the system and obtain the conditions of the system's non-fragile guaranteed performance.