Distributed H∞ filtering for interconnected large-scale systems with time-varying delays

This paper is concerned with the problem of distributed filtering for interconnected large-scale systems. The distributed states of large-scale systems are estimated. A system is considered to consist of several subsystems, to reduce the dimensions of results. It is also assumed that there is a local estimator for each subsystem separately. These local estimators can be designed by different algorithms. The proposed algorithm in this paper is a filtering method using linear matrix inequalities. Reduction of estimation error and convergence of states and their estimation has been proved. The whole system is decomposed into three interconnected subsystems that interact with each other. To evaluate the filtering performance, the proposed method is applied to a model of an active vehicle suspension system in the presence of time-varying delay. Also, the simulation results with the road profile show that the proposed method is independent of the road profile.