Modeling and Critical Winding Geometric Parameter Identification for the Near Electric Field from Helical Inductors

With the development of power electronics, the switching speed and switching frequency is increased to achieve higher power density. However, with the increased power density, components are positioned closer to each other, which increase the concerns of near field coupling. In non-isolated power converters, inductors are identified as major sources of electric field. This paper develops a fundamental theoretical model to quantify the relationship between helical windings and the near electric field. The developed theoretical model reveals that the inductors with helical winding structure will become an unintentional antenna that generate near electric field. It is recognized in this paper the geometric parameters such as the winding radius and the distance between winding layers are factors that influence the electric near field. The theoretical model is verified through the experiments and ANSYS HFSS simulations. Based on the model, the near electric field can be reduced by winding structure design.