Sliding Mode Control For Nonlinear Time Delay System

As a robust control method, sliding mode variable structure control is widely used to design the controller with uncertainty system. The important advantage of this control mode is for some uncertain factors with full robustness in a certain environment, such as solving structural uncertainty and external disturbance influence as well as the internal parameter perturbation, etc.Uncertainty is ubiquitous in the real system.All sorts of practical engineering are running in a different and changing environment, so the dynamic performance of the system fully using the precise mathematical model to express is not realistic, also cannot achieve.Is thus result in system modeling errors, these errors may be due to ignore the system nonlinear characteristics, low or high order by order instead of the cause.Other system changes in the environment, the changes in the internal parameters and then external disturbance such as harmful to nonlinear system.Through the study of sliding mode variable structure control for time-delay systems, the nonlinear systems controller can be designed by sliding mode control. Firstly, the delayed neutral system as the research object, the stability criterion can be get based on Lyapunov stability theorem, then the sliding mode controller can be designed for unstable systems. The feasibility of the controller is verified by Lyapunuv stability theory, the system performance is verified by simulation experiments.Secondly, for the nonlinear system, when the system states are not fully measurable, the observer and the system controller based on sliding mode variable structure control are designed, especially under the condition of system with uncertainties and external disturbances, the sliding mode controller guarantees the performance of the system. The controller is verified by Lyapunuv stability theory, and the system performance is verified by simulation experiments.