|
This study aims to develop a robust method to deal with fault detection and identification (FDI) for linear system subject to structured plant uncertainties or parameter variations. The approach consists of the use of a partial state observer and an augmented system accounting for possible sensor or actuator failures as well as plant uncertainties. The generated robust residual signals are sensitive to faults to be detected while insensitive to the plant uncertainties. It therefore serves as a fault indicator. The sufficient and necessary condition for the existence of robust FDI and its design procedure are presented; and the application is illustrated with the help of simulation studies performed on a vertical takeoff and landing helicopter. Superior to previous methods in the literature, the proposed method is able to classify the sensor and actuator failures simultaneously in the presence of both abrupt and smooth bias faults.
|