Robust adaptive fault‐tolerant control for linear systems with actuator failures and mismatched parameter uncertainties

Abstract

In this study, a direct adaptive control scheme is developed to solve the robust fault-tolerant control problem for linear systems with mismatched parameter uncertainties, disturbances and actuator faults including loss of effectiveness, outage and stuck. Although the unparameterisable time-varying stuck faults and the upper bounds of disturbances are unknown, the adaptive laws are proposed to estimate the unknown controller parameters online. Then, by using the information from the adaptive mechanism, a class of robust adaptive state feedback controllers are constructed for automatically compensating the actuator faults, external disturbances and mismatched parameter uncertainties. Moreover, on the basis of Lyapunov stability theory, it is proved that the resulting adaptive closed-loop system can be guaranteed to be asymptotically stable in the presence of actuator faults, disturbances and mismatched parameter uncertainties. Finally, simulation results are presented to illustrate the efficiency of the proposed fault-tolerant design approach.