Large Helical Device

The Large Helical Device (大型ヘリカル装置, Ōgata Herikaru Sōchi) is a fusion research device in Toki, Gifu, Japan and is the second largest superconducting stellarator in the world, employing a heliotron magnetic field originally developed in Japan.

The objective of the project is to conduct fusion plasma confinement research in a steady state in order to elucidate possible solutions to physics and engineering problems in helical plasma reactors. The LHD uses neutral beam injection, ion cyclotron radio frequency (ICRF), and electron cyclotron resonance heating (ECRH) to heat the plasma, much like conventional tokamaks.