versão impressa ISSN 0012-7353
A technique for design of unknown inputs observers is presented, applied to the solution of fault detection problem. The proposed technique is mainly based on observation of error signals known as residuals, which are obtained by taking away actual input from estimated input. In an unknown inputs observer the state estimation error vector approaches zero asymptotically, regardless the presence of the unknown inputs or perturbations in the system. Diagnosis algorithm was satisfactorily tested in a hydraulic liquid level system in simulation as well as real time.
Palavras-chave : Fault detection; Unknown Input Observers; Stability.