Delay-dependent Stability Analysis For A Class Of Time-varying Delay Systems With Fault

With the continuous development of industrial technology and the enlargement and complexity of modern control systems,dynamic systems are widely used in engineering practice.To ensure system safety and reduce the loss has become one of the main purposes of the scholars in the field of control.One of the key technologies in the control field is fault estimation and fault-tolerant control technology,which has become an important means to improve the security and stability of the system.Therefore,the requirements of fault estimation and fault-tolerant control technology are increasingly high,so the update and development of these technologies is an inevitable trend.In addition,the phenomenon of time delay widely exists in various industrial systems,which may lead to system stability imbalance or system oscillation.The stability of a control system is the basic premise for the normal operation of the system.The fault-delay compensation control technology studied in this thesis can better weaken the negative impact of time delay on the system under consideration,so as to maintain the safe and stable operation of the system.Therefore,the study of tolerant control and stability analysis for time-delay systems has important theoretical significance and application value.In this thesis,the delay-dependent stability analysis of a class of time-varying delay systems with faults is studied.The main work is as follows:(1)For a class of linear systems with time-varying state delay,an output feedback controller based on fault-delay compensation is designed.This controller can effectively reduce the negative effects of time delay on the system.At the same time,a less conservative time-delay dependent stability condition based on LMI closed-loop system is obtained.Different from the previous inequality reduction and Lyapunov function optimization techniques,this chapter obtains the upper bound of the time-delay tolerance of the system from the controller design.The effectiveness of the proposed method is verified by a simulation example.(2)For a class of time-varying delay systems with Lipschitz nonlinear terms,the problems of fault tolerance and delay weakening are further studied.Based on the designed adaptive fault-tolerant controller,the coefficient matrix of the time delay term of the system under consideration can be optimized,which can not only reduce the negative impact of the time delay term,but also obtain a larger time-delay allowable upper bound of the system.A simulation example is given to verify the effectiveness of the method.