Loss Reduction by Laminating Ferrite E Cores

Abstract:
Due to the increasing switching frequencies in power electronics, macroscopic eddy currents in ferrites and the associated losses have to be increasingly considered. Especially for cores with larger cross sections, the effect occurs already at lower frequencies. The reduction of eddy current losses in SiFe cores by lamination is already well known. This work applies the principle of lamination to ferrite cores of the sizes E70, E42 and E36 of the material MF106 (comparable to N97). The effect of lamination is investigated in the small-signal range using the loss tangent (tandelta) and at higher flux densities up to 500 kHz at 25 °C and 100 °C using rectangular voltage excitation.