An Integrated Design for Robust Actuator Fault Accommodation based on H∞ Proportional-Integral Observer

The main contribution of this paper is an integrated design of robust fault estimation (FE) and fault accommodation (FA), applied to uncertain linear time invariant (LTI) systems. In this design, the robust H-infinity proportional-integral (PI) observer allows a precise estimation of actuator fault by dealing with system disturbances and uncertainties, while the feed-back controller compensates the actuator fault, and therefore assuring the closed-loop stability. Thanks to the application of majoration and Young inequalities, the observercontroller decoupling problem is solved and both above objectives are combined into only one linear matrix inequalities (LMI) allowing a simultaneous solution for both observer and controller. Finally, an example of vehicle suspension system is illustrated to highlight the performance of the proposed method.