Routh-approximation based model reduction using series expansion of interval systems

This paper presents a method for the reduction of the order of interval system using Routh approximants. A new method is proposed to calculate time moments that is computationally simpler and easier, does not require to calculate time moments by expansion of denominator of system, γ-δ parameters or γ parameters. The generated low-order models always possess stability and initial time moments of the high-order system. Typical numerical examples illustrating the proposed method are provided.