Thermal Quench Behaviors of No-Insulation Coils Wound Using GdBCO Coated Conductor Tapes With Various Lamination Materials

This paper presents the quench initiation and propagation characteristics of no-insulation racetrack coils wound using three types of Cu-stabilized GdBCO coated conductors (CCs), with SUS and brass laminations, and without lamination. The test results show that the minimum quench energy values of the brass-laminated GdBCO CC coil were larger than those of the SUS-laminated one. Moreover, the normal zone propagation velocities of the brass-laminated GdBCO CC coil were greater than those of the SUS-laminated one due to the higher thermal conductivity of brass. Moreover, the nonlaminated GdBCO CC coil exhibited greatly improved thermal stability compared to the brass/SUS-laminated GdBCO CC coils, because the local heat in the event of quenching was easily dissipated due to the absence of lamination.