Improved calculation of winding losses in gapped inductors

Field patterns in gapped inductors are more complicated than the fields in transformers, thus the winding losses in inductors are given with higher complexity. An improved presentation of winding losses in inductors is reported, using a correction loss factor. The full expression of that correction loss factor, called kF, is tuned using FEM calculations. An approximation of kF as a function of a parameter κ is provided. The parameter is depending on the sum of the distance coil–air gap and 1∕3 winding thickness, divided by the window width. The features of the approach are the fast and straight winding loss calculation combined with sufficient accuracy and wide application for gapped inductors with different frequencies, wire diameters, conductor fittings, and core and air gap constructions.