Analysis Of Asymptotic Stability And L2-performance For Neutral Delay Linear Systems With Actuator Saturation

It is well-known that nonlinear constraint always exists in control systems. In various nonlinear constraints, actuator saturation appears most usually and complicates the system control problems. It is desired to solve the problems in theory or practice. Furthermore, delay phenomenon also exists everywhere. There is delay not only in state but also in derivative of the state, namely neutral delay linear systems. When the saturation constraint and neutral term exist in the delay system, the problem is more difficult to resolve regardless of the way in which the saturation exists in the neutral system. So it is important to study the neutral delay systems with actuator saturation.In this thesis, both asymptotic stability and L2-performance for neutral delay linear systems with actuator saturation are discussed, mainly using Lyapunov approach and combining with linear matrix inequality(LMI). Several types of saturated neutral asymptotic stability criterion and L2 stability criterion and the composite controller design method are given. Both of the above problems are studied in this paper. It is organized as follows:First, the problems of asymptotic stability of the saturated neutral systems with mixed-delays, distributed delays and nonlinear perturbations are studied. Based on the Lyapunov stability theory, the system asymptotic stability criteria and the robust asymptotic stability criteria and the composite controller design approach are given in terms of LMIs. It is convenient to estimate the domain of attraction because the criteria are LMIs.Second, the problems of L2-stability of the saturated neutral systems with mixed-delays, distributed delays and nonlinear perturbations are studied. Using linear matrix inequality approach, two set domains where the smaller one is included in the larger one are designed. When disturbance exists, the trajectories of the closed-loop system from the smaller set can also remain in the other one, and the corresponding closed-loop system is finite gain L2-stable. In addition, when the disturbance does not exist, the corresponding closed-loop system is robust internal stability, and the larger one is included in the domain of attraction of the closed-loop system, so it is contractive invariant.