The Research On Robust Fault-tolerant Control For Uncertain Time-delay Systems

The reliability of control systems is the key to operate normally for the systems. It has very important signification to ensure the reliability and the security of modern complex systems. The coming of the fault-diagnosis and fault-tolerant control technology provides a new method to improve the reliability of modern complex systems. Because of the abundant applied background of uncertainty and time-delay in practice and the complexity of analysis and synthesis, the study of the fault-tolerant control problem of uncertain time-delay systems has an important value in theory and in practice.Due to the safety of large scale complicated control systems, linear continuous uncertain time-delay systems is considered as control subject in this paper. Based on lyapunov stability theory, memoryless state feedback control, time-delay state feedback control and linear matrix inequality method, the fault-tolerant control problem is studied in my work. There are main aspects in the work as follows:1. The fault-tolerant control problem is studied for linear continuous systems with time-delay. The sufficient condition for the systems against sensor or actuator failure possessing integrity is given by adopting memoryless state feedback control law or memory state feedback control law. The results of simulation demonstrate the effectiveness and feasibility of the presented method, and it shows that the introduction about time-delay state feedback control law not only improves the linear matrix inequalities resolvable, but all results dependents on delay.2. The robust fault-tolerant control problem is studied for the linear continuous systems with uncertain time-delay. Firstly, the considered systems have time-delay in state and the admissible parameter uncertainties of state and control input are unknown and norm bounded. The sufficient condition and controller design method for the systems against actuator or sensor failures possessing robust integrity are given by adopting memoryless state feedback control law or memory state feedback law. Secondly, the robust integrity problem is studied for the systems possessing time-delay in both state and control input by adopting the similar method. Furthmore, when the number of actuator is equal to the number of sensor in the same closed-loop systems, it reveals that the design of robust fault-tolerant controller against sensor or actuator failures are equivalent in mathematics, and all results undependents on delay. Lastly, the results of simulation demonstrate the effectiveness and feasibility of the presented method for different controlled plant and different control law, and it shows that the robust fault-tolerant controller are equivalent in mathematics,exchangeable in practice and universality of applicable for the different systems with time-delay. 3. The problem of robust fault-tolerant control for the time-varying delayed uncertain systems is studied. Firstly, the considered systems have uncertain linear controlled plant with time-varying delay. The sufficient condition and controller design method for the systems against actuator or sensor failures possessing robust integrity are given by adopting memoryless state feedback law. Secondly, the robust integrity is studied for the systems possessing time-varying delay in both state and control input by adopting the similar method. Lastly, the results of simulation demonstrate the effectiveness and feasibility of the presented method for different controlled plant and different control law. Furthmore, when the number of actuator is equal to the number of sensor in the same closed-loop systems, it shows that the robust fault-tolerant controller are equivalent in mathematics and exchangeable in practice, and all results dependents on delay.