Investigation and Optimization for Planar Coupled Inductor dual-phase interleaved GaN-based Totem-Pole PFC

This paper presents the comparison among different coupled inductors for the GaN-based critical mode (CRM) Totem-Pole PFC. The flux linkage and flux density are deduced both for the positive coupled inductor and the negative coupled inductor. The interleaving layout winding also has been researched for dual-phase coupled inductors. It also investigates both the winding loss and core loss of different coupled inductors. The result shows that the negative coupled planar inductor employing interleaving winding layout can achieve the smallest power loss. Furthermore, a simplified digital control strategy that can make the control design easy to implement for CRM Totem Pole PFC has been proposed and finally it was evaluated by a 1kW MHz dual-phase interleaved Totem-Pole PFC converter prototype.