MATLAB Source Code: Frequency-Partitioning Fitting Method for Linear Equivalent Identification from Frequency Response Data

It is often the case that the frequency response data of a system or a network is available and one wants to identify a linear equivalent from the frequency response data for time-domain simulations and other purposes. To this end, a variety of methods have been proposed, and the vector fitting (VF) method and the frequency-partitioning fitting (FpF) method are often used for electromagnetic transient (EMT) simulations of power systems. The main applications are frequency-dependent transmission-line modeling and frequency-dependent network modeling, but they should be applicable to various engineering and scientific problems where a pole-residue representation of a linear multi-input multi-output (MIMO) system has to be identified from its frequency response data.