Large scale interval system modelling using Routh approximants

Abstract

The authors present a new method for reducing the order of large scale interval systems using Routh approximants. The method is computationally simple, requires only the γ table and avoids the need to formulate both γ - δ tables and evaluate the time moments of the original system in advance unlike in other methods. The method always generates low-order models, which retain the stability and initial time moments of the original high-order interval system. Typical numerical examples illustrating the proposed method are provided.