ECCD Experiments in Heliotron J, TJ-II, CHS and LHD , TJ-II Team c) , CHS Team d) and LHD Team

Electron cyclotron current drive (ECCD) experiments have been made in stellarator/heliotron (S/H) devices such as Heliotron J, TJ-II, CHS and LHD. The experimental results show that ECCD can be controlled by the power injection angle, absorption position and magnetic field structure. The current drive efficiency is similar, γ = n e I EC R/P EC =8-16×10 16 A/Wm 2 , ζ=32.7n e I EC R/P W T e =0.03-0.05. The reversal of driven current direction is observed depending on the magnetic field ripple structure, indicating that the amplitude and direction of EC current is determined by the balance between the Fisch-Boozer effect and the Ohkawa effect, and that the Ohkawa effect is strong in S/H devices compared with tokamaks. Control of net toroidal current by using ECCD is demonstrated; net zero current state is attained by cancelling the bootstrap current