Methods for loss reduction in planar inductors

Abstract

Numerical analyses of the current distribution in a single rectangular conductor sandwiched by a pair of magnetic substrates, which form a base for understanding AC resistance of the conductor, are presented. The inductance and AC resistance of an inductor in which meander coil is embedded in the one magnetic substrate of a pair and is covered with the other with a given air gap between the two substrates are calculated. The role of the air gap in governing tradeoff between the copper losses and the iron losses as well as the value of inductance is shown. Characteristics of inductors fabricated using NiZn ferrites and an embedded meander coil are presented. A mesh coil by which eddy currents losses in the magnetic core can be reduced is described.<>