Detective Method of Local Normal-State Transition in No-Insulation REBCO Pancake Coil
賈 昀昊, 王 韜, 池田 愛花, 大木 隆宏, 石山 敦士 （早大）； 野口 聡, 門馬 克敏 （北大）； 渡辺 智則, 長屋 重夫 （中部電力）
Abstract:In the practical operation of high-field generation magnet applying in magnetic resonance imaging, the HTS coil may not only experience such unpredictable accidents like power failure, fire or earthquake but also occurs local superconductive property decay. If any of these accidents occurs, the magnet must immediately shut down to ensure the safety of the HTS coil. Therefore, sensitive, swift and efficient quenching detective is immediately required for the HTS coil, even though in the No-Insulation (NI) coil which is expected that possess a high thermal stability as well as a high current density. In this study, we assume that a local normal-state transition occurred in an NI coil during a constant operation current. For the NI coil, we prepare a scheme of search-coil to detect the magnetic variation during local normal-state transition. To design an optimized scheme of search coil for detecting the local normal-state transition, we conduct PEEC-thermal coupled analysis, and evaluate the specific of search coil for various sensitivity.