A complete optimal air gapped PFC boost inductor design for power converter applications

This paper summarizes the ratio of direct to ripple current as a key factor to determine inductor winding and core gap effects related to inductor performance. The new proposed multi-layer winding configuration (identical DC resistance per layer) is recommended to optimize the total winding loss. A solution is proposed to improve harmonic content and is verified experimentally in terms of harmonic and EMI emission. An effective mathematical inductance model of the curve-gapped inductor solution is derived, and a complete optimal PFC inductor design procedure is given.