Adaptive estimation and output feedback FTC for nonlinear systems with unknown nonlinearities and faults

Abstract

SummaryThe adaptive estimation mechanism and output feedback fault‐tolerant control (FTC) design is concerned for nonlinear systems with faults, where the unknown nonlinearities are not required to satisfy the Lipschitz condition. An intermediate variable–based adaptive output feedback FTC with an adaptive parameter estimator and an adaptive state tracker is designed. The designed controller can be updated online to compensate the effect of nonlinearities and process faults on systems so that the states of the closed‐loop transformed system are uniformly bounded. The control output is able to be adjusted online by the designed event‐triggering mechanism to maintain fluctuating within a prescribed small range. Numerical examples exhibit the simulation results under the proposed FTC.