Networked Control Systems(NCSs) are spatially distributed systems that the communication of sensors, actuators and controller etc occurs through the networks. The control of NCSs compares to the traditional point-to-point control mode, there are many advantages, for example, the lower cost of installation and implementation, simpler installation and maintenance, flexible architectures and so on. Hence, networked control systems have been used in a wide range of areas. However, because of the present of the network, the phenomenon with network-induced delay, pocket-dropout and packet out-of-order etc is frequently encountered in the practical network control systems, Which of the existence destroys the stability of systems and results poor control performance severely. The stability is not only basic demand of the dynamical system, but also necessary precondition of keeping system in gear. Hence, it is necessary and significant to study the stabilization of a class of networked control systems with both network-induced delay and pocket-dropout in the design and application of real control systems. In the past twenty years, many people have paid attention on the stability analysis of the networked control systems and achieved great results.By using the Lyapunov second method, a full-order linear compensator is utilized to compensate, combining with Leibniz-Newton formula, employing the linear matrix inequality (LMI), recurring to LMI toolbox in MATLAB, a few models and sufficient conditions for such systems are derived. specifically includes the following two aspects:1.The problem of the model and stabilization for a class of uncertain time-delay network control systems. A discrete model in which a full-order compensator is utilized to compensate network-induced delay is established through defining a augmented state vector method. then based on Lyapunov stability theory and matrix theory, sufficient conditions of asymptotic stability of closed-loop systems are derived,and the state feedback controller is obtained based on the feasible solution of the linear matrix inequalities(LMI).The simulation results verifies the validity of the proposed method. 2.Network-induced time-delay and pocket-dropout are existence inevitably in the control of NCSs, and in practical applications, model of systems is nonlinear. On the basis of the last chapter, the problem with the stabilization of a class of nonlinear networked control systems with both time-delay and pocket-dropout is further researched. A model in which the total of pocket-dropout between the adjacent sampling period is given, a pocket-dropout is considered as a special kind of network-induced delay and a full-order linear compensator is utilized to compensate both network-induced delay and pocket-dropout is established through defining a augmented state vector method. By constructing Lyapunov functions, linear matrix inequality (LMI) is employed. A few sufficient conditions for such systems are derived, and the state feedback control is obtained. The given example shows the method is effective.At last, we sum up all the paper and give some expectations of modeling and stability study for the networked control system. |