In the Advanced Fusion Research Center, steady state operation methods of a tokamak device have been developed using the superconducting high-field tokamak TRIAM-1M, and the sustainment of tokamak plasma with the duration of more than 5 hours has been succeeded, which is the world record until the present day. Elucidation of mechanisms of various plasma-wall interaction phenomena in such ultra-long duration discharges has been carried out and the sig-nificant results have been achieved. Moreover, long sustainment of the high performance plasma has been attempted and the High Ion Temperature Mode and Enhanced Current Drive Mode have been studied. Based on the acquired knowledge of the steady state tokamak operation and of the plasma-wall interaction of the ultra-long duration discharge, we have proposed the studies of long term sustainment of a spherical to-kamak (ST) as the next project, i.e. the project of QUEST (Q-shu Univ. Exp. with Steady-State ST) and the construction has been completed in March 2008.
Main research purposes of the project are as follows: