Actuator fault diagnosis for a class of time-delay systems

This paper presents a novel approach for the actuators fault diagnosis of time-delay systems by using an adaptive observer technique. The systems considered are subjected to an unknown input that represents either model uncertainty or external disturbances. At first, fault detection observer and fault diagnosis observer for linear actuators are designed. An extension to nonlinear actuators is then made, and a convergent adaptive diagnostic algorithm is developed. Finally, two numerical examples are given to illustrate the efficiency of the proposed method.