A Half-turn Winding Layout in Planar Transformers

This paper presents an analysis of the current distribution on the parallel conductors of typical interleaved planar transformers. Through the investigation, it is discovered that the S-P-S-P-S winding layout with "n+1" parallel layers exhibits a half-turn winding current distribution, resulting in lower AC resistance. Simulation and experiment results are used to validate the current distribution in the proposed half-turn transformer, demonstrating a nearly 20% reduction in winding loss and leakage inductance compared to conventional layouts.