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Journal of Applied Nonlinear Dynamics 6(2) (2017) 153--171 | DOI:10.5890/JAND.2017.06.003

Jay L. Adams; Robert J. Veillette; Tom T. Hartley

Department of Electrical and Computer Engineering, University of Akron, Akron, OH44325-3904, USA

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Abstract

A model-reduction methodology for fractional-order systems based on the Hankel-norm is presented. The methodology involves the truncation of a Laurent series associated with the fractional-order system in a transformed domain. The truncated Laurent series coefficients are used to construct a finite-order transfer function to approximate the original system. Standard model-reduction techniques are then applied to obtain a final low-order approximation. The Hankel norm of the approximation error can be specified a priori. The approximation method is applied to several fractional-order and other infinite-order systems. It is shown to be more generally applicable than standard finite-order modeling techniques.

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