AC Losses of Multifilamentary Bi-2223/Ag Conductors with Different Geometry and Filament Arrangement

This paper presents results from numerical modeling of non-twisted multifilamentary Bi-2223/Ag conductors with various geometry and filament arrangement. Anisotropic models of Jc(B) and n(B) have been employed in finite element method simulations under different operating conditions – with applied ac transport current, in external parallel and perpendicular ac magnetic field, and with combined current and field of varying orientation. AC losses and current distributions in square and round Bi-2223/Ag wires with different filament arrangement have been calculated and compared to those of a 7-filamentary tape. It is demonstrated that the shape factor of the conductors and the orientation of the local magnetic field with respect to the individual filaments are of primary importance for the ac loss magnitude in different applications. Outlined are the advantages of using conductors with specific filament configuration for a given application.