Verification of real-time polarization-controlled microwave reflectometry for magnetic field vector profile measurement

• Project/Area Number: 16K14525
• Research Category: Grant-in-Aid for Challenging Exploratory Research
• Allocation Type: Multi-year Fund
• Research Field: Nuclear fusion studies
• Research Institution: The University of Tokyo
• Principal Investigator: INOMOTO Michiaki 東京大学, 大学院新領域創成科学研究科, 准教授 (00324799)
• Co-Investigator(Renkei-kenkyūsha): TOKUZAWA Tokihiko 核融合科学研究所, ヘリカル研究部, 准教授 (90311208)
• Research Collaborator: KAWAMORI Eiichirou
• Project Period (FY): 2016-04-01 – 2018-03-31
• Project Status: Completed (Fiscal Year 2017)
• Budget Amount: ¥3,770,000 (Direct Cost: ¥2,900,000、Indirect Cost: ¥870,000); Fiscal Year 2017: ¥910,000 (Direct Cost: ¥700,000、Indirect Cost: ¥210,000); Fiscal Year 2016: ¥2,860,000 (Direct Cost: ¥2,200,000、Indirect Cost: ¥660,000)
• Keywords: プラズマ計測 / 核融合 / マイクロ波反射計 / 磁場閉じ込め核融合プラズマ / 球状トカマク / 磁場分布推定 / 内部磁場分布 / 核融合磁場閉じ込めプラズマ

Outline of Final Research Achievements

A novel polarization-controlled microwave reflectometry was proposed to measure the internal magnetic field profiles of fusion core plasmas. A full wave calculation code was developed and quantitative assessment for mode conversion was carried out on one- and two- dimensional geometries. The control part to rotate the polarization angle was fabricated using variable gain amplifiers and phase shifters. The amplitude of two input waves for a dual polarized antenna was quickly changed within 4 micro seconds, resulting in a control frequency of up to 100 kHz. In order to adjust the polarization angle with the magnetic field on the plasma surface, the modified Cauchy Condition Surface method was employed to reconstruct the last closed flux surface with high accuracy while large eddy current was induced on the vessel wall. These results showed high feasibility for the proposed polarization-controlled microwave reflectometry.

Research Products

• [Int'l Joint Research] 台湾成功大学(台湾)
• [Journal Article] Magnetic island dynamics in magnetic reconnection in UTST experiments (2018)
  • Author(s): Kamio S.、Inomoto M.、Yamasaki K.、Yamada T.、Cheng C. Z.、Ono Y.
  • Journal Title: Physics of Plasmas Volume: 25 Issue: 1 Pages: 012126-012126
  • DOI: 10.1063/1.5006092
  • Peer Reviewed / Int'l Joint Research
• [Journal Article] Reconstruction of plasma shape and eddy current profile based on modified cauchy condition surface method in merging spherical tokamak (2017)
  • Author(s): T. Ushiki, M. Inomoto, M. Itagaki
  • Journal Title: Fusion Engineering and Design Volume: 122 Pages: 36-41
  • DOI: 10.1016/j.fusengdes.2017.09.012
  • NAID: 120006734151
  • Peer Reviewed
• [Journal Article] Separated Double-Current Layers in a High-Guide-Field Reconnection Experiment (2017)
  • Author(s): Kyohei Kondo, Michiaki Inomoto, Xuehan Guo, Tomohiko Ushiki, Takumichi Sugawara, Takumi Mihara, Shuji Kamio, Hiroshi Tanabe, Yasushi Ono
  • Journal Title: Plasma and Fusion Research Volume: 12 Issue: 0 Pages: 1202033-1202033
  • DOI: 10.1585/pfr.12.1202033
  • NAID: 130006081763
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Presentation] 偏波制御型マイクロ波反射計による磁気シア分布測定法の開発 (2017)
  • Author(s): 南 佑典、井 通暁、徳澤 季彦、河森 栄一郎、笠原 寛史、辻村 亨
  • Organizer: Plasma conference 2017
• [Presentation] Plasma shape reconstruction of merging spherical tokamak in UTST device (2017)
  • Author(s): T. Ushiki, M. Inomoto, M. Itagaki, S. McNamara
  • Organizer: 19th International Spherical Torus Workshop
  • Int'l Joint Research
• [Presentation] Plasma shape reconstruction for merging spherical tokamak based on modified CCS method (2017)
  • Author(s): T. Ushiki, M. Inomoto, M. Itagaki, S. McNamara
  • Organizer: 59th Annual Meeting of the APS Division of Plasma Physics
  • Int'l Joint Research
• [Presentation] Formation of Closed Flux Surfacces in Recnnection Current Layer by Accelerated Electrons during Merging Start-up of Spherical Tokamak (2016)
  • Author(s): M. Inomoto, K. Yamasaki, T. Ushiki, X. Guo, S. Kamio, R. Yanai, T. Sugawara, Y. Fukai, H. Yamanaka, R. Tamura
  • Organizer: 26th IAEA Fusion Energy Conference
  • Place of Presentation: Kyoto International Conference Center
  • Year and Date: 2016-10-17
  • Int'l Joint Research
• [Presentation] UTST合体プラズマにおけるCCS法を用いたプラズマ位置形状および渦電流分布再構成 (2016)
  • Author(s): 牛木知彦, 板垣正文, 井通暁
  • Organizer: 第１１回核融合エネルギー連合講演会
  • Place of Presentation: 九州大学伊都キャンパス
  • Year and Date: 2016-07-14
• [Presentation] プラズマ合体を用いた球状トカマクの立ち上げと加熱 (2016)
  • Author(s): 井通暁, 牛木知彦, 郭学瀚, 山田琢磨, 神尾修治, 山崎広太郎, 菅原拓路, 深井優介, 山中晴揮, 田村崚, 田辺博士, 小野靖
  • Organizer: 第１１回核融合エネルギー連合講演会
  • Place of Presentation: 九州大学伊都キャンパス
  • Year and Date: 2016-07-14
• [Presentation] UTST球状トカマク合体実験における中性粒子ビーム入射(NBI)追加熱の検証 (2016)
  • Author(s): 深井優介, 牛木知彦, 菅原拓路, 郭学瀚, 井通暁
  • Organizer: 第１１回核融合エネルギー連合講演会
  • Place of Presentation: 九州大学伊都キャンパス
  • Year and Date: 2016-07-14