A theoretical investigation on current imbalance in flat two-layer superconducting cables

A model for the simulation of current distribution in superconducting Rutherford cables is described. The model assumes that interstrand currents can flow continuously among the strands, as if the contact resistances were smeared along the cable length. The model is aimed at the simulation of the generation and development of long-range current loops in the presence of time-dependent magnetic fields. The results of the model are compared with those obtained through the lumped constant circuit model currently used to calculate the current distribution in Rutherford cables obtaining a good quantitative agreement. The model has also been applied to the study of current distribution in the Rutherford cable of a short LHC dipole magnet. The calculated values of current differences among the strands are in qualitative agreement with the experimental data on the amplitude of periodic oscillations of the magnetic field in the magnet bore. (19 refs).