Development of double-sided superconducting wire for high frequency and its application to high quality factor coil

Research Project

Project/Area Number	18K04230
Research Category	Grant-in-Aid for Scientific Research (C)
Allocation Type	Multi-year Fund
Section	一般
Review Section	Basic Section 21050:Electric and electronic materials-related
Research Institution	University of Yamanashi
Principal Investigator	SEKIYA Naoto 山梨大学, 大学院総合研究部, 准教授 (80432160)
Project Period (FY)	2018-04-01 – 2021-03-31
Project Status	Completed (Fiscal Year 2020)
Budget Amount *help	¥4,420,000 (Direct Cost: ¥3,400,000、Indirect Cost: ¥1,020,000) Fiscal Year 2020: ¥1,430,000 (Direct Cost: ¥1,100,000、Indirect Cost: ¥330,000) Fiscal Year 2019: ¥1,170,000 (Direct Cost: ¥900,000、Indirect Cost: ¥270,000) Fiscal Year 2018: ¥1,820,000 (Direct Cost: ¥1,400,000、Indirect Cost: ¥420,000)
Keywords	ワイヤレス電力伝送 / 高Q値コイル / 高温超伝導線材 / 超伝導RFコイル / 超伝導 / Q値 / 超伝導線材 / 超伝導コイル
Outline of Final Research Achievements	We have developed extremely high quality (Q) factor superconducting coil comprising two conventional high-temperature superconducting (HTS) tapes for radio frequency applications. A method of joining two HTS tapes by using dielectric film tape was developed. A styrene foam coil-support configuration that has lower effective dielectric loss was developed. The skin effect of the Ag protection layer was suppressed by making it thinner than the conventional one. A coil using the proposed tape had a measured Q factor of about 20,000, which is about 20 times that of one using Cu tape. The large improvement of the power transfer efficiency of wireless power transfer system was obtained using the proposed coil compared to copper coil.
Academic Significance and Societal Importance of the Research Achievements	学術的意義：開発した高Q値コイルは従来技術では実現できない飛躍的に高いQ値を実現し，それを使ったワイヤレス電力伝送の効率が大幅に改善することを実証した．これら成果は未開拓であった超伝導線材の高周波応用分野の先駆けとして重要な意義を持つ．社会的意義：高周波用超伝導線材を用いた高Q値コイルはワイヤレス電力伝送の送受電コイルやMRIの信号検出コイルに使用することで，効率や感度を大幅に改善することができるため，未来の非接触電力供給技術や医療の向上などに貢献できる．