# Influence of single layer winding geometry of inductive element on loss resistance

## Authors

• Andrii Seredin National Technical University of Ukraine “Igor Sikorsky Kyiv Polytechnic Institute”, Kyiv, Ukraine
• Andriy Movchanyuk National Technical University of Ukraine “Igor Sikorsky Kyiv Polytechnic Institute”, Kyiv, Ukraine

## Abstract

The Dowell and Ferreira calculation methods for the loss resistance of choke windings are analyzed in this paper. We determine that the neglect of the winding geometry influence is the cause of their error, because the problem is solved on a plane. The influence of winding geometrical parameters on current distribution in conductors is investigated for verification. The influence of single layer winding geometry on loss resistance for conductors of different diameters is considered. It is determined that the influence of winding geometry on the loss resistance is significant (up to 40%), and it increases with increasing conductor diameter and frequency, and decreasing coil diameter. There is non-uniformity in current distribution of coiled into a ring conductor caused by proximity effect. The influence of inter-winding distance for a single layer winding on its loss resistance is studied. The influence of interturn proximity effect is significant and increases with decreasing inter-winding distance. The reason for discrepancy with known methods is the non-uniformity of current distribution in the outer and inner turns. The peculiarities of current distribution in square cross-section conductors and equivalent in area cylindrical conductors presented as straight single conductors, single turns, and single layer windings are considered. The influence of the conductor shape on current distribution and its density are determined.

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