Losses in multifilamentary superconductors at low levels of excitation

Results are presented of a theoretical analysis and experimental study of coupling losses in the matrix of twisted multifilament superconducting wires in transverse variable magnetic fields. The data obtained relate to a range of the amplitudes and rates of the field variations such that no saturation of the superconducting filaments with induced current is attained. Cases of periodic and single field pulses of different shape were analyzed to show a considerable effect of these factors upon losses. It is shown that the loss dependence upon the twist pitch and matrix resistance is different for different pulse shapes.