Fast Adaptive Fault Estimation and Accommodation for Nonlinear Time-varying Delay Systems
Résumé
his paper studies the problem of fault estimation and accommodation for a class of nonlinear time-varying delay systems using adaptive fault diagnosis observer (AFDO). A novel fast adaptive fault estimation algorithm that does not need the derivative of the output vector is proposed to enhance the performance of fault estimation. Meanwhile, a delay-dependent criteria is obtained based on free weighting matrix method with the purpose of reducing the conservatism of the AFDO design. On the basis of fault estimation, an observer-based fault-tolerant controller is designed to guarantee the stability of the closed-loop system. In terms of matrix inequality, we derive sufficient conditions for the existence of the adaptive observer and fault-tolerant controller. Simulation results are presented to illustrate the efficiency of the proposed method.