Development of super-high-speed pellet injection system using high-temperature superconducting linear catapult

2020 Fiscal Year Final Research Report

• Project/Area Number: 17K06999
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Nuclear fusion studies
• Research Institution: National Institute for Fusion Science
• Principal Investigator: Yanagi Nagato 核融合科学研究所, ヘリカル研究部, 教授 (70230258)
• Co-Investigator(Kenkyū-buntansha): 本島 厳 核融合科学研究所, ヘリカル研究部, 准教授 (00509507) ; 高山 彰優 山形大学, 大学院理工学研究科, 助教 (70396589)
• Project Period (FY): 2017-04-01 – 2021-03-31
• Keywords: 磁気浮上 / 高温超伝導 / リニアカタパルト / ペレット

Outline of Final Research Achievements

A new pellet injection method using the superconducting linear catapult is proposed for fueling of a fusion reactor, and a proof-of-principal experiment as well as numerical simulations have been carried out. In the experiment, a miniature train having a high-temperature superconducting bulk was cooled by liquid nitrogen, and magnetically levitated above a railway consisting of neodymium magnets. The train was then accelerated using electromagnet coils placed along the railway. The timing for energizing the magnets was precisely determined by detecting the train’s position using a laser and an optical sensor with a control unit having a microprocessor and a IGBT switching circuit. The numerical simulation calculates the induced shielding current by applying magnetic field using the electromagnets, and the resultant electromagnetic force is calculated for acceleration. The result suggests that a 1 km/s of speed is obtained with a 1 km acceleration with a continuous acceleration.

Free Research Field

超伝導工学

Academic Significance and Societal Importance of the Research Achievements

磁場閉じ込め方式核融合炉の燃料ペレット供給のための新方法として高温超伝導リニアカタパルト方式を考案し、原理検証実験と数値シミュレーションを行った。これにより、今後の本格的開発によってこの射出方式が実際に適用できる可能性を見出すことができ、これにより将来の核融合炉プラズマの運転制御を容易にすることが期待される。また、この小型リニアカタパルトシステムは核融合炉だけでなく、他の工業用途にも適用できる可能性があり、高温超伝導の用途を広げる意味でも意義が大きい。