Coupling currents in Rutherford cables under time varying conditions

A network model is presented to simulate fully transposed Rutherford cables under time varying conditions. The intrinsic properties of the cable and the external applied conditions can be changed spatially. Several statistical distributions of the contact resistances are built in to investigate local differences in the coupling loss and in the eddy currents. The average loss is quite independent of the resistance distribution but locally both the loss and the eddy currents can increase significantly. The self field distribution of the cable is included, resulting in a saturation of the strands which depends on the relative direction between the magnetic field, the field sweep rate, and the transport current. Mutual inductances between strands are introduced, allowing the use of the model for nonstationary problems. Time constants can be calculated for both the coupling currents in the strands and for the local and global dissipation