Fault diagnosis and fault tolerant control for nonlinear satellite attitude control systems

In this paper, an integrated fault diagnosis and fault tolerant control scheme is investigated for nonlinear satellite attitude control systems. The fault diagnosis is performed by a novel interactive multiple model approach aiming at reducing the size of the model set. Unknown fault parameters are jointly estimated with system states by state augmentation and a bank of Unscented Kalman Filters. Based on the faulty information obtained from the fault diagnosis system, a proportional-derivative controller is used to recover the faulty system. Simulation results demonstrate the effectiveness of the proposed fault diagnosis and fault tolerant control scheme.