Balancing-Based Reduction for Interconnected Passive Systems

We propose a novel balancing-based reduction approach for the reduction of interconnected, passive LTI subsystems. This approach retains (strict) passivity and (asymptotic) stability of both the subsystems and the interconnected system. Simultaneously, we retain an accurate description of the input–output behavior of the interconnected system by accounting for the dynamics of the interconnected system in the reduction of the subsystems. A relevant structural dynamics benchmark of approximately two thousand states is presented, by which we verify the preservation of stability and passivity and demonstrate the superior model accuracy of the proposed reduction method with respect to existing methods from the literature.