Decentralized state estimation in large-scale interconnected dynamical systems
Decentralized control systems, decentralized observers, large-scale systems, unknown input observers
A simple approach for decentralized state estimation in large-scale control systems is proposed. Given that a large-scale dynamical system can be decomposed into a number of interconnected input-output decentralized subsystems, a method for designing totally decentralized local reduced order estimators is proposed. It is shown that totally decentralized state estimation may be possible as long as the number of the subsystem interaction inputs are less than or equal to the locally measured outputs. Here the interconnection effects among the subsystems are treated as totally unknown inputs to each subsystem. The method builds upon a novel approach in designing reduced order unknown input observers (UIO) for dynamical systems, and it therefore results in totally decentralized estimators' structure. The pros and cons of the estimation scheme are pointed out and necessary and sufficient conditions for designing local estimators are stated. Finally, the design approach is verified by a numerical example. © 1991.
Saif, Mehrdad and Guan, Yuping. (1992). Decentralized state estimation in large-scale interconnected dynamical systems. Automatica, 28 (1), 215-219.