Modeling of Magnetic Anisotropy Due to Compression Molding of Soft Magnetic Composite for Inductance Calculation

A modeling method of the anisotropic magnetic characteristics due to compression molding of a soft magnetic composite (SMC) for inductance calculation of an SMC inductor is proposed. First, a particle model with a flattened iron particle and a uniform layer of insulation is constructed to simulate the anisotropic BH curves in arbitrary directions using the measured limited two BH curves in the compress and vertical directions under compression. Then, the proposed particle model is expanded to include the dc-biased characteristic of permeability. Moreover, the proposed model is applied to two inductors with legs having different compress directions. It is shown that the proposed method can be applied to the optimal design of inductors taking account of the compress direction of SMC.