| ‘‘‘‘‘‘‘‘‘‘‘‘‘‘‘‘‘‘‘‘ KAWASAKI STEEL TECHNICAL REPORT No.39 ( October 1998 ) Electrical Steel ‘‘‘‘‘‘‘‘‘‘‘‘‘‘‘‘‘‘‘‘ |
| Frequency Dependence of the Complex Initial
Permeability of MnZn Ferrite Satoshi Gotoh, Takashi Kawano, Naoki Soga |
| Synopsis: The higher the real part of the complex initial permeability Κifof MnZn ferrites is, the lower is the frequency at which it begins to fall. This phenomenon has been explained by the domain wall resonance or the rotational resonance. The authors analyzed the frequency dependence of the permeability by taking into account the behavior of the electromagnetic wave derived from the cross section radius r, the resistivity Ο, and the complex permittivity Γ. The typical measured Κi, vs. frequency curve has a peak at a certain frequency fr, followed by a rapid fall. On the other hand, the resonant frequencies calculated from the rotational resonance and the domain wall resonance theory were much higher than the observed one. By considering the effect on the three parameters r, Ο and Γthe calculated curve reproduces the measured one which has a peak followed by a rapid fall. The frequency dependence of the Κi is consequently determined by the individual sample dimensions and the macroscopic electromagnetic properties. |
| TextiPDF: 7P/369kbj |