Analysis of Power Losses in Mn–Zn Ferrites

The power loss of Mn-Zn ferrites has been studied as a function of magnetic flux density and frequency. The exponent (x) of magnetic flux density was 2.94 at 100 kHz and 2.48 at 1 MHz. Results support the switch of power loss mechanism from hysteresis losses at low frequency to residual losses at 1 MHz. In the intermediate frequency range, eddy current loss was dominant. The power loss linearly increased with an exponent (y approx equals 1.25) at low frequency and deviated from the linearity at higher frequencies, where the exponent of frequency (y) was 2.87 at 100 C and 25 mT. The frequency at which the power loss starts to deviate from the linearity is in agreement with the onset frequency of the dissipation of magnetic permeabilities. Residual loss is associated with the magnetic resonant process. 14 refs.