Magnetic field analysis for dimensional resonance in Mn-Zn ferrite core and comparison with permeability measurement

Mn-Zn ferrite is widely used for inductors and transformers because of its high permeability and low loss in the low-frequency band. In this study, we attempted to perform the magnetic field simulation which is composed of the equivalent circuit and Maxwell equation for simulating both of the dimensional resonance and size-dependent core loss of Mn-Zn ferrite. By invocation of the equivalent circuit of Ref. [3], we used the relation between the current density and electric field with a dielectric effect of crystalline grain boundary. These equations are solved by coupling with Maxwell equation and magnetic property equation. To verify the effectiveness of the coupling analysis, we analyzed the frequency dependence of the permeability and the loss of several toroidal cores of different sizes as the first step.