Sliding mode observer based fault detection and isolation in descriptor systems

This paper considers the application of sliding mode observer to the problem of fault detection and isolation for descriptor system with input fault and measurement fault. In detecting and isolating the faults, we consider two cases where there exists only an input fault, and a measurement fault without the input fault in the system respectively. For each case, we propose an approach for designing a sliding mode observer and prove the stability of the state reconstruction error dynamics using the Lyapunov method. In this way, a feedforward injection map and compensation signal is defined and conditions which ensure the stability of the error reconstruction dynamics, and the existence of the sliding mode are presented. Also, this paper attempts its reconstruction as well as detection and isolation of each fault.