Adaptive compensation and H∞ optimization design of fault-tolerant control system with output feedback design

In this paper, the problem of designing adaptive fault-tolerant H_∞ compensation controllers for linear time-invariant continuous-time systems against general actuator faults is presented. Using mode-dependent Lyapunov functions method, linear matrix inequalities (LMIs) are developed to find stabilizing controller gains such that the disturbance attenuation performance is optimized. Direct adaptive control schemes are proposed to estimate the unknown controller parameters on-line for actuator fault and perturbation compensations. Then a class of adaptive robust dynamic output feedback controllers is constructed relying on the LMI result and the updated values of these estimations. Based on Lyapunov stability theory, it is shown that the resulting closed-loop systems can guarantee to be stable and suboptimal H_∞ performances in the presence of faults on actuators. A numerical example of a decoupled linearized dynamic aircraft system and its simulation results are given.