Unknown Input High Gain Observer for Parametric Fault Detection and Isolation of Dynamical Systems

An unknown input high gain observer based parametric fault detection and isolation scheme is presented. First, a reduced order unknown input high gain observer is derived. Then, using these observers, a fault detection and isolation technique is devised to detect and isolate the parametric fault of a system whose parameters are uncertain to some extent. The proposed FDI algorithm consists of two steps. In the first step, the detection of fault and the isolation of faulty region are achieved and in the next step, the faulty parameter is isolated from the faulty region. Effectiveness of the observer as well as the FDI technique is shown with the help of a numerical example.