Robust Fault-tolerant Control For A Class Of Uncertain Nonlinear Time-delay Systems And Its Application

With the development of science and technology, the control problem of uncertain nonlinear system with time-delay becomes hot issue in recent year. Lots of research results on the controller design and stability analysis have achieved. And they have widely been used in many practical applications. The thesis mainly pays close attention to the robust fault-tolerant control for a class of uncertain nonlinear system with time-delay and its application to the control of Tiltrotor. The contents are as follows:Firstly, aimed at the problem will be discussed, some relevant basic theories were introduced, including fault-tolerant control, robust control, Lyapunov stability theory, state feedback and Linear Matrix Inequality (LMI).Secondly, the robust fault-tolerant control problem for a class of nonlinear time-delayed systems with parameter uncertainties, which satisfy certain gain conditions are discussed. When the sensor or actuator breaks down, based on Lyapunov stability theory and the LMI method, the sufficient conditions for the solvability of the problem were given, and the corresponding controllers are constructed separately, which render the closed-loop system be asymptotically stable in two cases. The numerical examples are given to illustrate the effectiveness of the conclusions.Lastly, the obtained research results were applied to the lateral flight control of Tiltrotor. In the frame of Lyapunov stability theory, when the failure in sensor and actuator occurs, the corresponding robust fault tolerant controller is designed by using LMI, which guarantee the closed-loop systems be asymptotically stable regardless of all uncertainties. The validity of the controllers are verified via simulation.