Investigation of the effect of loop current with very long time constant on the stability of large superconducting coils

2019 Fiscal Year Final Research Report

• Project/Area Number: 15K05974
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Power engineering/Power conversion/Electric machinery
• Research Institution: National Institute for Fusion Science
• Principal Investigator: Obana Tetsuhiro 核融合科学研究所, ヘリカル研究部, 助教 (60435518)
• Project Period (FY): 2015-04-01 – 2020-03-31
• Keywords: 超伝導コイル / 超伝導導体 / 磁場測定 / 核融合

Outline of Final Research Achievements

We measured the self-magnetic field of a large-scale superconducting coil manufactured using a superconducting conductor composed of many strands. As a result, it was confirmed that a shielding current having a time constant of several hundred seconds at the longest was generated in the superconducting coil. Moreover, it was clarified that the cause of such a shielding current is related to the current path at the end of the conductor. Furthermore, the relationship between the non-uniform current distribution in the superconducting conductor caused by the shielding current and the thermal stability was clarified by numerical analysis.

Free Research Field

超伝導工学

Academic Significance and Societal Importance of the Research Achievements

次世代の発電として期待される磁場閉じ込め型核融合発電では、発電炉の中核機器として大型超伝導コイルが使用される。本研究では、大型超伝導コイルの開発を進める過程で重要となる実験データを収集することができた。更に、超伝導コイルに使用する超伝導導体の性能を評価するための解析コードを開発することができた。