Stability and Quench Behaviors of Conduction-Cooled 2G HTS Coil Cowound With SS Tape

We fabricated a second-generation (2G) high-temperature superconducting (HTS) model coil cowound by a 2G HTS tape and a stainless steel (SS) tape. The inner diameter of the model coil was 120 mm, and the number of turns was 100. A 2G HTS tape 12 mm in width manufactured by SuNAM Co., Ltd. in South Korea was used. The total length of the coil was 44 m, and the critical current (I c ) of the model coil was about 174 A in liquid nitrogen. The minimum quench energy(MQE) was 19.1-22.6 J, and the normal zone propagation velocity (NZPV) was 2.4-2.7 mm/s at 0.977 I c in liquid nitrogen. MQE was 2.85 J at 0.86 I c , and NZPV was 2.7 mm/s at 77 Kin conduction cooling. A 2G HTS coil cowound with an SS tape was robust in the event of the quench induced by heater and overcurrent flow above critical current.