[Table of Contents]

Plasma and Fusion Research

Volume 7, 2402116 (2012)

Regular Articles

Experiments of Tokamak Discharge and Simulation of Magnetic Field Configuration in Tokamak-Helical Hybrid Device TOKASTAR-2
Makoto HASEGAWA, Kozo YAMAZAKI, Hideki ARIMOTO, Tetsutarou OISHI, Reiya NISHIMURA and Tatsuo SHOJI
Department of Energy Engineering and Science, Graduate School of Engineering, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8093, Japan
(Received 9 December 2011 / Accepted 7 May 2012 / Published 13 September 2012)


TOKASTAR-2 is a small tokamak-helical hybrid device which can generate tokamak and helical configurations independently. In tokamak discharge experiment, the conductive shell was installed to increase plasma current by controlling the displacement of ohmically heated (OH) plasma. The suppression of the vertical displacement was demonstrated, but the OH plasma was still located slightly above the mid plane. To compensate this displacement, the balance between up and down vertical field coil currents should be adjusted. In addition, the construction of additional helical field coils is planned to form closed vacuum magnetic surfaces. The magnetic field line tracing analysis was carried out to determine the detailed shape and location of additional helical field coils. From the simulation, it was clarified that the location of magnetic surfaces and the averaged value of rotational transform can be controlled by adjusting coil current ratios.


tokamak-helical hybrid, tokamak discharge, fast camera, helical coil, vacuum magnetic surface

DOI: 10.1585/pfr.7.2402116


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This paper may be cited as follows:

Makoto HASEGAWA, Kozo YAMAZAKI, Hideki ARIMOTO, Tetsutarou OISHI, Reiya NISHIMURA and Tatsuo SHOJI, Plasma Fusion Res. 7, 2402116 (2012).