Core loss analysis of soft magnetic composites considering the inter-particle eddy current loss

Soft magnetic composite (SMC) is composed of ferromagnetic particles surrounded by electrical insulation layer. During the manufacturing process, the electric insulation layer may be destroyed and thus the eddy current will be induced, which makes it difficult to calculate the accurate eddy current loss. In this paper, the inter-particle eddy current loss is calculated at the macro-scale by modeling the actual sample and using the measured conductivity of the sample, moreover intra-particle eddy current loss is calculated by modeling single particle of SMC base on the existing model. Then, under different particle sizes and frequencies, the influence of skin effect on the calculation of eddy current loss is analyzed. Finally, to verify the proposed model, the iron losses of two SMC materials are calculated and they are compared with measured results. It can be seen that when the inter-particle eddy current loss has been considered, then the core loss of SMC will be agreed very well with the measurement results, thus the proposed model can be used for the actual core loss calculation for the electrical machine or other electromagnetic device with SMC cores.