Expansions in spherical harmonics for the modeling of near-field coupling in EMC

In EMC behavior of power electronic converters, it is important to predict near-field coupling between the complex components (e.g. in EMC filter). By using the components of near-field multipolar expansion of electromagnetic sources, the close magnetic coupling between two sources is determined from their equivalent model. It is shown that the complete identification of all components of multipolar expansion provides a more precise representation of the near-field around sources and thus a better accuracy of the near-field coupling prediction. Also theoretical and experimental developments are presented.