| Fault-tolerant control (FTC) is a rising cross-discipline. Its science significance lies in that it can guarantee system's asymptotic stability when component failures occur during the process of system operation. Practical engineering project requires that control system must meet the need for one or more than one performance index. Consequentlly, fault-tolerant control design considering performance indices must be discussed if fault-tolerant control theory can be applied to actual engineering system. In fact, reliable control is the fault-tolerant control which takes into account performance indices. Apparently reliable control accords with practical engineering background.Time delay is a common phenomenon in industries. The existence of time delay not only results in instability and performance deterioration of system but aslo makes designing controller to be difficult. Study for the time-delay system has high both theoretical and practical significance. On the other hand, due to the limitation of model-building techniques and the variation of plant parameters, it is impossible that plant model builded accords completely with actual plant. More or less, there always exists error model between them. Such error is named as uncertainty. Obviously, control system dealling with both uncertaity and time delay mentioned above has background of practical engineering. Consequentlly it has very significant theory and application value to research robust reliable control for uncertain time delay system.In this dissertation, considering one or more than one performance index such as guaranteed cost index and exponential stabilization index as well as H-infiniti constraint, on the basis of the Lyapunov stability theory (including Lyapunov-Razumkhin stability theory) and by means of linear matrix inequalities(LMIs), we mainly study the problem of robust reliable control via state feedback, static output feedback and dynamic output feedback for the uncertain time delay system against actuator or sensor failures, respectively. Our aim is that robust reliable control system designed can meet demands as following:(1) The closed-loop control system can tolerate sensor or actuator failures.(2) The closed-loop control system is insensitive to system parameter disturbance as well as enviroment noise disturbance.(3) The closed-loop control system possesses not only robust stability but aslo robust performance indices.The main researches include as follows:(1) As for sensor failures of on-off model, the problem of robust reliable control via state feedback is studied for uncertain time-varying delayed system. ①Firstly, considering exponential stabilization index alone, reliable control with exponential stabilization is investigated. Based on Lyapunov stability theory, a sufficient condition for the existence of reliable controller with exponential stability is derived and transformed to a LMI. Furthermore, the design approaches and steps of reliable controller are given.②Secondly, on the basis of above research, considering both exponential stabilization index and H_∞index, robust H_∞reliable control with exponential stabilization is discussed. Sufficient conditions of the existing of robust controller are presented and transformed to two LMIs, and the associated designing approach of state-feedback controller is provided.(2) As for three kinds of actuator failure models, the problem of robust reliable control via state feedback is studied for uncertain time-delayed system.①Firstly, as for actuator failures of on-off model, considering H_∞index, robust H_∞reliable control is investigated for time-varying delayed uncertain systems. Based on Lyapunov-Razumkhin stability theory, a sufficient condition of the existing of robust reliable controller possessing H_∞performance index is given and the associated designing approach of state-feedback controller is presented. Those results are represented by LMIs and are correlative with time delay. Our method can be applied to fast time-varying delay system.②Secondly, as for actuator failures of gain model, considering both exponential stabilization index and guaranteed cost index, guaranteed cost reliable control with exponential stabilization is investigated for time-varying delayed uncertain systems. Based on Lyapunov stability theory, a sufficient condition for the existence of the reliable controller is derived and transformed to a LMI.③Thirdly, as for actuator failures of aggregative model, considering b.oth exponential stabilization index and guaranteed cost index, guaranteed cost reliable control with exponential stabilization is investigated for time-varying delayed uncertain systems. Based on Lyapunov stability theory, a sufficient condition for the existence of the reliable controller is derived and transformed to a LMI.④Fourthly, as for actuator failures of aggregative model, considering both exponential stabilization index and H_∞index, robust H_∞reliable control with exponential stabilization is investigated for time-varying delayed uncertain systems. Based on Lyapunov stability theory, sufficient conditions of the existing of robust reliable controller are presented. Those conditions are transformed to two LMIs. ⑤Finally, as for actuator failures of on-off model, considering both guaranteed-cost index and H_∞index, guaranteed-cost H_∞robust reliable control is investigated for time-delayed uncertain systems. Based on Lyapunov stability theory, a sufficient condition for the guaranteed-cost H_∞robust reliable controller is established.(3) As for actuator failures of on-off model, the problem of robust H_∞reliable control via static output feedback is studied for uncertain time-varying delayed system. Based on Lyapunov-Razumkhin stability theory, a sufficient condition of the existing of robust reliable controller possessing H_∞performance index is given and the associated designing approach of static output feedback controller is presented. Those results are represented by LMIs and are correlative with time delay.(4) As for actuator failures of on-off model, based on dynamic output feedback, the problem of guaranteed cost reliable control and the problem of H_∞reliable control are investigated, respectively.①Firstly, guaranteed cost reliable control is investigated for uncertain delay system. By means of variables switchover, two LMIs which are the sufficient condition of the existing of guaranteed cost reliable controller are given and the associated designing approach of dynamic output feedback controller is presented.②Secondly, reliable H_∞control is investigated for time-varying delayed systems. By means of variables switchover, two LMIs which are the sufficient condition of the existing of reliable H_∞controller are given and the associated designing approach of dynamic output feedback controller is presented.
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