Integrated active and passive fault-tolerant control for a class of non-linear uncertain systems with time-varying delay

For a class of non-linear uncertain systems with time-varying delay, fault-tolerant controller design is investigated for the actuator faults, where the actuator faults including the cases of loss of effectiveness, bias faults, outage, and stuck faults. For more general consideration, the bias/stuck faults are assumed to be a state-dependent time-varying part and a constant part. The controller design combines the advantages of the active approach and passive approach. Designing the adaptive law, the actuator fault value is estimated on-line and the controller is designed to compensate the fault. Meanwhile, a fixed controller is designed to dealing with other stability effect factors. Based on the Lyapunov stability theory and linear matrix inequality (LMI), the stability of the closed-loop system is proved. The proposed methods have solved the stability decrease of the system that caused by the actuator faults, system uncertainties and time-varying delay of the state. Finally, the developed design techniques have been applied to an annealing furnace. The validity of this approach is also been demonstrated by simulation results.