A Vector Fitting Procedure for the High-Frequency Model Generation of Inductive Components

In order to simulate resonances in power electronic circuits and for EMC predictions, detailed high-frequency impedance models of the components must be used. Models with a relationship to physical reality are particularly useful for deriving design optimizations. In this work, a generally usable procedure for the generation of models for inductive power electronic components from impedance measurements is shown. A passive equivalent circuit model is determined from a rational function approximation generated by vector fitting in several steps. The procedure is shown for the secondary coil of a high-voltage transformer used in a resonant converter.