Research On Control Method Of High Order Delay Nonlinear System

This paper considers the design and analysis of stabilizing controller for high-order nonlinear systems with time-delays. The main contributions include:Chapter 1 investigates the global stabilization problem for a class of high-order nonlinear systems with multiple time-varying delays. The novelties are that the investigated systems included both low-order and high-order nonlinearities, and the order of nonlinearities can take values in certain intervals. By introducing a novel Lyapunov-Krasovskii functional, a state feedback controller based on the Lyapunov-Krasovskii theorem together with the adding a power integrator and sign function methods is designed to guarantee the globally uniformly asymptotic stability of the closed-loop system.Chapter 2 studies the global adaptive stabilization of a class of high-order uncertain nonlinear feedback systems. A remarkable characteristic of the systems to be investigated is that the growth condition on nonlinearities is further relaxed by allowing not only input and state delay but also the unknown rate. By using a combined method of adaptive technique, dynamic gain control and adding a power integrator, a state feedback controller based on Lyapunov-Krasovskii theorem is designed to guarantee that all signals are bounded, the equilibrium of the closed-loop system is globally stable and the original state converges to zero.Chapter 3 gives summary and outlook of the thesis.