Fault diagnosis and fault-tolerant control for remote monitoring systems with delayed controls and measurements

Facing to the remote monitoring systems with delayed controls and measurements in facility agriculture, the problems of fault diagnosis and fault-tolerant control were investigated. The optimal fault-tolerant control law for faulty systems was designed, and the uniqueness of the optimal fault-tolerant control law was proved. In order to diagnose faults and to solve the physically unrealizable problems of the optimal fault-tolerant control law, a delay-free transformation approach was given for delayed measurements. The on-line fault diagnosis and the observation of system states were realized by constructing the reduced-order state observer for the augmented system comprising fault states. Finally, the physically realizable dynamic optimal fault-tolerant control law was obtained by utilizing the results of fault diagnosis. Simulation results demonstrate the validity of both the fault diagnosis scheme and the dynamic optimal fault-tolerant control law.