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Japan · Magnetic confinement (stellarator/heliotron)

Large Helical Device

Operated by National Institute for Fusion Science · First operation 1998

Status: Operational

Japan's superconducting heliotron — for decades the largest stellarator-class device, pioneering steady-state magnetic confinement.

LHD at Toki, Japan uses two continuous helical coils rather than the modular coils of W7-X. It pioneered superconducting steady-state operation and high-density plasma research.

Key specifications

Major radius
3.9 m
Magnetic field
3 T
Plasma volume
30 m³

Milestones

  1. 1998

    First plasma

  2. 2017

    Deuterium experiments begin

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