Thermal quench study in HTSC pancake coil

摘要

In spite of rather high general stabilityof high temperature superconducting (HTSC) Hi-basedmagnets, catastrophic thermal quench (TQ) may appearin them under certain circumstances. It happens becauseof non-linearity of voltage-current characteristics inHTSC superconductors. Starting with small samples inour previous works, we continue to study the TQ withlarge samples. We prepared a highly instrumented HTSCpancake coil. It is wound using the Bi-2223-based tape.We attached many potential taps to the tape andinstalled in the winding 10 cryogenic thermocouples (TC)and two heaters. Quench development in the coil wasmeasured under different temperatures, differentmagnetic fields and different cooling conditions. Inthis paper, the experimental details and the resultsobtained are presented. The results are discussed fromthe point of view of scaling theory for quenching in HTSC devices.