Sensorless Diamagnetic Measurement of Plasma Energy in Spherical Tokamak

2015 Fiscal Year Final Research Report

• Project/Area Number: 25630422
• Research Category: Grant-in-Aid for Challenging Exploratory Research
• Allocation Type: Multi-year Fund
• Research Field: Nuclear fusion studies
• Research Institution: Kyushu University
• Principal Investigator: NAKAMURA Kazuo 九州大学, 応用力学研究所, 教授 (30117189)
• Co-Investigator(Renkei-kenkyūsha): MITARAI Osamu 東海大学, 熊本教養教育センター, 教授 (00181925) ; IIO Shunji 東京工業大学, 原子炉工学研究所, 教授 (90272723)
• Research Collaborator: FUJITA Hiroki 九州大学, 大学院総合理工学府, 修士課程
• Project Period (FY): 2013-04-01 – 2016-03-31
• Keywords: 球状トカマク / プラズマエネルギー / 反磁性測定 / センサーレス測定 / ファラデー回転 / ファイバー光学 / 偏波面回転型光CT / ループ型サニャック干渉計

Outline of Final Research Achievements

In the spherical tokamak QUEST, when plasma energy increases by heating, toroidal magnetic field in the plasma varies from the toroidal magnetic field in vacuum due to diamagnetic effect. If the voltage induced in the toroidal magnetic field coil is measured, the increase in the plasma energy can be estimated inversely. And when the voltage applied to the toroidal field coil is constant, the increase in the plasma energy can be estimated inversely by measuring the induced current change with optical CT (Cuurent Transformer based on Faraday rotation). We adopted Sagnac interferometer without detection error even for the optical fiber deformation due to the temperature change and the vibration.

Free Research Field

核融合学