Design of fullorder fault detection observer based on algebraic approach
(1. School of Automation, Beijing Information Science and Technology University, Beijing 100092, China; 2. School of Physics and Electronic Engineering, Hanshan Normal University, Chaozhou, Guangdong 521041, China; 3. Department of Electrical Engineering, Tsinghua University, Beijing 100084, China)
Abstract：Aiming at the linear timeinvariant systems with mismatched unknown disturbances, the design approach of fullorder fault detection observer was combined with modeling technique of unknown disturbance to design the detection observer for decoupling the unknown disturbance. Employing the algebraic modelling technique, the matched unknown disturbances were separated from the unknown disturbances, while the mismatched unknown disturbances were remained. An augmented system based on the combination of the original system and the mismatched unknown disturbances model was constructed to satisfy the rank condition. A fullorder observer was designed for the augmented system, and the conditions for the existence were analyzed. The residual generated by the fullorder observer was robust to the unknown disturbances while sensitive to the faults. The proposed method was applied to a class of vertical takeoff and landing helicopter system, and the system model was simulated. The simulation results show that the proposed fullorder fault detection observer is effective.
