Comparison of measurements and electromagnetic field analyses of time-changing magnetic field of an HTS magnet

• Project/Area Number: 19K23513
• Research Category: Grant-in-Aid for Research Activity Start-up
• Allocation Type: Multi-year Fund
• Review Section: 0302:Electrical and electronic engineering and related fields
• Research Institution: Kyoto University
• Principal Investigator: Sogabe Yusuke 京都大学, 工学研究科, 助教 (40847216)
• Project Period (FY): 2019-08-30 – 2021-03-31
• Project Status: Completed (Fiscal Year 2020)
• Budget Amount: ¥2,860,000 (Direct Cost: ¥2,200,000、Indirect Cost: ¥660,000); Fiscal Year 2020: ¥1,430,000 (Direct Cost: ¥1,100,000、Indirect Cost: ¥330,000); Fiscal Year 2019: ¥1,430,000 (Direct Cost: ¥1,100,000、Indirect Cost: ¥330,000)
• Keywords: 高温超伝導 / マグネット / 磁界精度 / 磁界測定 / 電磁界解析 / 加速器用マグネット / 遮蔽電流磁界 / 粒子加速器

Outline of Research at the Start

高温超伝導技術を粒子加速器用マグネットへ応用する上で課題となっている遮蔽電流磁界と呼ばれる付加的に発生する磁界成分の、発生磁界を変化させながら運転する変動励磁と呼ばれる運転においてどのような特性を示すかを、磁界測定及び電磁界解析の比較を通して明らかにする。様々な通電パターンで変動励磁した場合に高温超伝導線内部に誘導される遮蔽電流の振舞いを電磁界解析によって明らかにし、高温超伝導マグネット内部の電磁現象がマグネットの発生磁界に与える影響を実験的・解析的に解明する。

Outline of Final Research Achievements

A small-scale high-Tc superconducting magnet consisting of coils wound with coated conductors was experimentally measured under repeated excitations, which simulate the operation pattern required for particle accelerator magnets.
In addition, a precise electromagnetic field analysis model was applied to visualize the behavior of the shielding current, which is an electromagnetic phenomenon inside the coated conductors, during repeated excitations, and to clarify the influence of the shielding current on the magnetic field quality of the magnet. The results were compared with the experimentally measured magnetic field.

Academic Significance and Societal Importance of the Research Achievements

高温超伝導技術を加速器用マグネットに応用する際に問題となる変動励磁時の高温超伝導マグネットの発生磁界の実験的・解析的評価は世界初の試みであり、本研究の成果は、将来的な高温超伝導技術の高エネルギー物理学用加速器や医療用加速器への応用の足掛かりとしての学術的意義をもつ。高エネルギー物理学用加速器への高温超伝導マグネットの適用は素粒子研究をさらに進展させるために必要不可欠とされており、医療用加速器への高温超伝導マグネットの適用は重粒子線がん治療をさらに普及させるための必要条件と位置付けられており、本研究は高温超伝導マグネットの特性に関する基礎研究という意味での社会的意義をもつ。

Research Products

• [Presentation] Behavior of shielding-current-induced field in a small magnet wound with coated conductors under time-varying field generation operations (2020)
  • Author(s): Naoyuki Amemiya
  • Organizer: 10th Asian Conference on Applied Superconductivity and Cryogenics (ACASC), 2nd International Cryogenic Materials Conference in Asia (Asian ICMC)
  • Int'l Joint Research
• [Presentation] Measured and calculated magnetic field of a small dipole magnet wound with coated conductors during repeated ramping up/down operation (2020)
  • Author(s): Koki Wakabayashi
  • Organizer: 2020 Applied Superconductivity Conference (ASC 2020)
  • Int'l Joint Research
• [Presentation] 伝導冷却された小型高温超伝導二極マグネットの変動励磁下での発生磁界測定 (2020)
  • Author(s): 曽我部 友輔
  • Organizer: 第99回2020年度春季低温工学・超電導学会研究発表会
• [Presentation] 繰り返し変動励磁下での小型高温超伝導二極マグネットの発生磁場の実験及び解析による評価 (2020)
  • Author(s): 曽我部 友輔
  • Organizer: 第100回2020年度秋季低温工学・超電導学会研究発表会
• [Presentation] Behavior of shielding-current-induced field in a small magnet wound with coated conductors under time-varying field generation operations (2020)
  • Author(s): Yusuke Sogabe, Koki Wakabayashi, and Naoyuki Amemiya
  • Organizer: 10th Asian Conference on Applied Superconductivity and Cryogenics（ACASC）, 2nd International Cryogenic Materials Conference in Asia（Asian ICMC）
  • Int'l Joint Research
• [Presentation] Behavior of shielding-current-induced field in a small HTS magnet under time-dependent field generating operation (2019)
  • Author(s): Yusuke Sogabe and Naoyuki Amemiya
  • Organizer: Joint KU - VUW Workshop 2019
  • Int'l Joint Research