Effect of Tape's Ic Inhomogeneity and Strand Misalignment on the Transport Capacity of Roebel Cables

In calculations for predicting the performance of high-temperature superconducting (HTS) cables, uniform physical and geometrical properties of the tapes are usually assumed. However, commercially available coated conductor tapes present a certain nonuniformity of their transport capability-namely their critical current-along the length. In addition, when coated conductor strands are compactly assembled to form a Roebel cable, their arrangement is far from the ideal one. In this work, we calculate the influence of Ic nonuniformities and of nonperfect strand alignment on the critical current of Roebel cables made of an HTS-coated conductor tape. For this purpose, we perform a statistical analysis using a recently developed and freely available open-source code to calculate the critical current of Roebel cables. We find that, for the considered cases, the nonuniformity of the strands' I-c can have a significant impact on the final critical current of the cable, whereas the influence of the misalignment of the strands is rather low.