Thermal recovery of inductive superconducting fault current limiters with weak zones inthe secondary

Abstract

We study here the limitation performance and the thermal recovery of inductivesuperconducting fault current limiters (SFCL) with special emphasis on the case in whichthe superconducting element (i.e. the secondary) has weak zones. Our experimental resultsindicate that the conduction of heat between a hot weak zone and its cold surroundingsplays an important role in its refrigeration. This suggests that it could be interesting todesign superconducting elements based on an appropriate distribution of artificialweak zones. In this way, the heat would be removed more efficiently than in thecase of homogeneous samples, where the heating would be uniform. By using anumerical simulation it is found that, with a proper distribution of artificially createdweak zones, it could be feasible to simultaneously get a good current limitation(as big as with homogeneous secondaries) and a shorter recovery time. Theseresults suggest an unexpected way to improve the performance of any SFCL.