Stability Analysis And Control For Networked Systems With Time Delay And Packet Dropout

Networked control system (NCS) is fully distributed feedback loopcontrol system which is built through wired or wireless communicationnetwork. Compared with traditional point-to-point control systems, net-worked control systems have lots of advantages, such as, flexible struc-ture, low industrial costs, high security and so on, so it is widely used inaerospace, transportation, medical, military, power and many other fields.However, the intervention of the network will result in time delay of datatransmission, packet dropout and so on, these can cause serious influenceon the performance and stability of the system, which makes the analysisand design of networked control system complex. The main researchworks of this paper about the problems in the networked control systemare as follows:1) The problem for the robust stability of networked control systemswith time delay and packet dropout is investigated. Packet dropout is as-sumed as a special kind of delay, and based on the delay-departioningmethod, a novel Lyapunov-Krasovskii functional with triple-integralterms is built, and combined with reciprocally convex combination tech-nique, a new stability criterion which makes networked control systemasymptotically stable is established. Finally, numercial examples demon-strate the superiority of the proposed method in this paper.2) The robust H filtering problem for a class of networked controlsystems with random sensor delay is studied. The sensor delay is sup-posed to a stochastic variable satisfying Bernoulli binary distribution，andnetworked control systems are represented as time-delay systems. Bybuilding a new Lyapunov-Krasovskii functional and introducing wirt-inger’s inequality approach, the H performance of the system is ana-lyzed, and the sufficient conditions are derived to ensure that the filteringerror system is exponentially stable, so theH filter is designed. Finally,a numercial example demonstrates the effectiveness of the proposedmethod for the robust Hfilter in this paper. 3) The problem of robust guaranteed cost fault-tolerant control isaddressed for a class of uncertain networked control system with timedelay and packet dropout. By selecting a appropriate Lyapunov–Krasovskii functional, the sufficient conditions which ensure that the system isexponentially stable with a prescribed performance level are derived. Theproblem of guaranteed performance optimization is transformed intoconvex optimization problem with constraint conditions of linear matrixinequalities, and the parameter expressions of robust guaranteed control-ler are given. Finally, a numercial example demonstrates the effectivenessof the proposed method for the robust guaranteed cost fault-tolerant con-trol in this paper.