Highly Efficient Inductor Design Using X-Winding Concept with Distributed Air Gaps

This work introduces a novel design method to reduce power losses caused by fringing fields in high-power-density inductors. By integrating circular clearances and distributed air gaps, the proposed design leverage fringing flux to uniform current distribution in the winding, thereby minimizing AC resistance. Compared to the conventional methods, the proposed method achieves both lowest core profile and AC resistance. In 3D finite element method (FEM) simulations, it achieves a 35% reduction in AC resistance compared to a conventional EE core design with a same box volume, and a 33% lower core profile than a conventional EI core design with even 15% lower AC resistance. Finally, the proposed X-winding concept is applied in printed circuit board (PCB) and the simulation results are verified by experimental measurements.