Abstract: Current drive is one of the major issues in controlled nuclear fusion research field. For the steady state operation, a variety of current drive methods are under systematic investigation. Helicity injection current drive is an attractive method. The experiment on Helicity Injected Tokamak(HIT) in U.S. obtained 150 kA toroidal driven current applying the coaxial helicity injection, which is the most remarkable results. This paper reports the results about equilibrium reconstruction in the above mentioned experiment. The driven current profiles and magnetic topology are consistent with the MHD equlibrium constraint from magnetic measurement data by using EFIT equilibrium fitting code. The reconstruction shows that these plasmas have a Tokamak q profile, with a hollow toroidal current profile and up to 110 kA of closed field toroidal current in a low aspect ratio configuration. Calculation results also indicate that plasma relaxed state is a non complete relaxation state away from Taylor State.

Key words: helicity injection, current drive, equilibrium reconstruction