Network Control System Robust Stability

The analysis and synthesis of network control systems is one of the main topics of the international control field. As a latest theory, the research and application of network control system is developed rapidly since it is proposed. In the network control, the network system is a typical time-delay system since the impact of the network environment is usually manifested as Packets delay and lost in transmission while Packets lost can be transformed into delay sometimes. Therefore, for all the research of network control systems, the stability is the foundation no matter which branch we study. Therefore, the research of network systems stability is attracting more and more attentions. Moreover, some remarkable achievement has been gained. Based on the Lyapunov stability theory and linear matrix inequalities (LMI) technique, this dissertation investigates the stability problem of the network systems with delay-dependent, which includes the global asymptotic stability analysis and the robust stability analysis. The results obtained is easily to realize in the MATLAB and thus has high theoretical instructive significance for the design of practical control system. This dissertation is consisted of five chapters:.The first chapter introduces the background of the network control system and its development history, the current research situation of the stability of network control system with time-delay, and briefly states the main contributions of this dissertation.The second chapter describes the characteristics of the network-induced delay, Lyapunov stability theory, the basis methods of time-delay systems, and the necessary lemmas and the LMI theory used in this dissertation.In the third chapter, based the Lyapunov stability theory and linear matrix inequalities (LMI) techniques, by constructing a Lyapunov-Krasovskii function, we study the robust asymptotic stability problem for a class of input-output channel polytopic uncertain network control systems with same time-delay. Also, the criteria for the robust asymptotic stability is presented for this system.In the fourth chapter, based the Lyapunov stability theory and linear matrix inequalities (LMI) techniques, by the model transformation and the decomposi- tion of coefficient, the robust asymptotic stability problem for a class of multi-ple-input and multiple-output channel network control system with time-delay and nonlinear perturbations is investigated. Also, the conditions for the robust asymptotic stability is presented for this system is shown with the form of LMI, which can be verified by the LMI toolbox of Matlab.Finally, we summarize the entire dissertation and point out the future work to be further investigated, and discuss the future study of the stability of the network control systems.