Adaptive higher order sliding mode observer-based fault reconstruction for a class of nonlinear uncertain systems

In this paper, we consider the fault reconstruction problem of a class of nonlinear uncertain systems with Lipschitz nonlinearities. An adaptive law is designed for estimating the uncertain parameters and adaptive-gain super-twisting(STW) sliding mode observer is developed for observing the system states. The inherent output injection feature of super-twisting algorithm is then used for fault signal reconstruction. The feasibility and effectiveness of the proposed approach is demonstrated through a simulation example of a nonlinear fuel cell system.