This paper presents a novel decentralized scheme for actuator fault detection and isolation of a class of large-scale interconnected nonlinear systems. For each of the interconnected subsystems, a local nonlinear unknown input observer (UIO) is designed without the need to communicate with other agents. The interconnected terms are treated as unknown inputs, hence all subsystems are decoupled completely and the information of other subsystems is not needed for fault detection and isolation. In addition to the interconnections, an exogenous disturbance which contains both system and measurement noise is approximately decoupled. To facilitate the observer design, sufficient condition for existence of the designed observer is formulated in terms of a set of linear matrix inequalities (LMIs) and optimal gain matrices are obtained. A simulation example of an automated highway system demonstrates the effectiveness of the proposed methodology.
Unknown Input Observer (UIO), Large-Scale System, Decentralized Fault detection and Isolation.
Amir ABBASI, Javad POSHTAN, Ali MOAREFIANPOUR, "A Decentralized Approach Based on Unknown Input Observers for Actuator Fault Detection and Isolation of a Class of Interconnected Nonlinear Systems", Studies in Informatics and Control, ISSN 1220-1766, vol. 25(4), pp. 453-460, 2016. https://doi.org/10.24846/v25i4y201606