Measuring the current distribution in a 10 m long high temperature superconducting cable conductor

To obtain realistic data on high temperature superconducting (HTS) conductors, a 10 m long cable conductor was built using 193 HTS tapes placed in eight concentric layers. To fully exploit the current carrying capability of all the HTS tapes and to minimise the AC losses the conductor was designed to have an almost even current distribution with respect to the HTS tapes. The outer diameter of the former was 35 mm and the outer diameter of the conductor was about 40 mm. A thin layer of electrically insulating Mylar™ foil was wound between each HTS layer. This way, the current in one particular layer may be treated as a tubular current sheet. The current in each layer was determined using custom made flat Rogowski coils placed between the superconducting layers. For this conductor, each layer was carrying <25% of the total load current. © 2002 Elsevier Science B.V. All rights reserved.