Abstract

Durability of superconductors used to fabricate superconducting power machines is important, since the machines need to operate stably. Quench properties of GBCO (GdBa₂Cu₃O₇) coated conductor tapes laminated with brass were measured and analyzed to investigate the durability of tapes under repeated short-circuit conditions. With short currents applied to the tapes repeatedly, the quench properties of tapes were measured, and bubbles generated during quenches were observed. The results showed that quench resistance and distribution were maintained after repeated quenches. They were maintained after repeated quenches at various applied voltages, which show durability of the tapes under repeated short-circuit conditions. The quench distribution was uniform throughout repeated quenches, which contributed to the durability of tapes.

• Keywords: GBCO coated conductor, Quench properties, Repeated quenches