Design Study for the Large Helical Device

The Large Helical Device (LHD) is a Heliotron/torsatron-type superconducting helical confinement fusion device, which is scheduled to be built by the newly established National Institute for Fusion Science in Japan. The design study is described. The goal of the LHD is to demonstrate high energy confinement and high beta in a helical device, which are necessary steps toward a helical reactor system.