Self-field Loss in AC Transport Current Loss of MgB₂ Superconducting Composites

Abstract

The measurement and analysis of AC transport current loss (self-field loss) in MgB₂ superconducting composites were studied. In experimental results, the normalized I_c dependency of AC loss in the MgB₂ deviated from Norris' theoretical curve. Then a numerical analysis was performed by taking into consideration the model of a round superconducting wire that consisted of three concentric layers. The analysis clearly showed the experimentally obtained results, such as that the phenomenon originated in the inhomogeneity of the critical current density in the wire rod section.