Effects of Lateral-Tailoring of Coated Conductor for Ac Loss Reduction of Superconducting Power Transmission Cables

The effects of removing low-
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edges of coated conductors by a laser for ac loss reduction were studied in two-layer superconducting power transmission cables. By removing the low-
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edges, narrower coated conductor with more uniform
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distribution can be obtained. The original 5 mm-wide coated conductors as well as the edge-removed 4 mm-wide and 3 mm-wide coated conductors were assembled spirally around cyrindrical formers in two layers to form a cable. The measured ac losses were compared with the ac losses calculated using a numerical model where the spiral structure is neglected. For ac loss calculations, we used the lateral
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distribution of the coated conductor measured by the magnetic knife method or those which are assumed based on the losses of the critical current by the edge removal.