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DOE OSTI · 1603892

A Multi-Function AAA Algorithm Applied to Frequency-Dependent Line Modeling: Preprint

Monzon, Lucas·Johns, William·Dasharati Iyengar, Spatika·Reynolds, Matthew·Maack, Jonathan·Prabakar, Kumaraguru
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Abstract

We present a new multi-input rational approximation algorithm (MIAAA) and illustrate its advantages respect to the popular Vector Fitting (VF) algorithm using examples of approximations of admittance matrices discussed in a very recent paper and by the creators of VF. We show that not only MIAAA outperforms VF in terms of achieving better accuracy using a smaller number of poles, but also has no numerical issues to achieve convergence. In contrast to VF, MIAA is not sensitive to the location of input sample points and it does not require good estimates for the location of the desired approximation poles.

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97 MATHEMATICS AND COMPUTINGAAA algorithmbarycentric formulacomputational modelingfunction approximationpower system modelingrational approximationsvector fitting

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Monzon, Lucas, Johns, William, Dasharati Iyengar, Spatika, Reynolds, Matthew, Maack, Jonathan, Prabakar, Kumaraguru. 2020-03-03. A Multi-Function AAA Algorithm Applied to Frequency-Dependent Line Modeling: Preprint. https://www.osti.gov/biblio/1603892

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