Reduction of Hot-Spot Temperature of REBCO Coil by Use of Stabilizing Cu Strips on REBCO-Coated Wire

Abstract

The most probable cause of quench damage of a rare earth barium copper oxide (REBCO)-coated wire is localized overheating at a hot-spot in the wire of the REBCO coil during the quench protection sequence. An effective method for reducing the hot-spot temperature is to increase the thickness of the Cu layer of the coated wire. However, it is difficult and costly to obtain a thick Cu layer with a uniform thickness and a flat surface by plating. In this paper, the effectiveness of forming a coil by placing bare stabilizing Cu strips on the bare surface of the Cu layer of a REBCO wire as an alternative method to the plating of a thick Cu layer is investigated. Experiments show that the use of stabilizing Cu strips provides quench protection performance that is equivalent to that obtained by increasing the Cu layer thickness of the REBCO wire.