Plasma and Fusion Research

Volume 11, 2405034 (2016)

Regular Articles

NITA Coil — Innovation for Enlarging the Blanket Space in the Helical Fusion Reactor
Nagato YANAGI, Takuya GOTO, Hitoshi TAMURA, Junichi MIYAZAWA and Akio SAGARA
National Institute for Fusion Science, 322-6 Oroshi-cho, Toki 509-5292, Japan
(Received 30 November 2015 / Accepted 2 February 2016 / Published 15 April 2016)


An innovative idea is proposed for enlarging the blanket space on the inboard side of the torus for the helical fusion reactor FFHR-d1. A set of sub-helical coils, named NITA coils, with opposite-directed current outside the main helical coils, effectively reduces the helical pitch parameter and enlarges the blanket space. Dependence of the blanket space and plasma volume on the effective helical pitch parameter is examined. The obtained magnetic surfaces and their properties are compared with that of the original configuration.


helical fusion reactor, FFHR-d1, optimization of heliotron magnetic configuration, blanket space, NITA coil

DOI: 10.1585/pfr.11.2405034


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