Efficient Offline Compensation of In-Air Magnetic Flux for Accurate Characterization of Soft Magnetic Materials

This paper proposes an efficient and easily applicable offline method to compensate for the air magnetic flux in the characterization of soft magnetic materials using the Epstein Frame. The proposed approach does not necessitate the incorporation of additional components into the experimental setup or the implementation of complex methodologies for the evaluation of the surface of the Epstein coil. The proposed strategy has undergone rigorous evaluation for three distinct Fe-Si commercial stripes, encompassing Non-Oriented Grain (NOG) and Oriented Grain (OG) specimens with varying thicknesses and Silicon percentages. In any case, given the independence of the proposed procedure from the material nature, it can be applied to each variety of soft magnetic material. The results obtained have been presented in the form of magnetization curves and magnetic losses across a broad spectrum of frequencies. A comparison of these results with the data provided by manufacturers has been conducted, thereby substantiating the efficacy of the proposed approach despite its apparent simplicity compared with those proposed by the standard. The findings underscore the paramount importance of implementing compensation techniques to circumvent persistent errors in the assessment of soft magnetic materials' performance, particularly in scenarios characterized by elevated magnetic density flux values. This imperative is of primary significance for the development of accurate magnetic materials models and for the prediction of power system behavior in fault conditions.