Experimental study of discharge cleaning on EAST by helicon plasma

摘要

High power steady operation of Experimental Advanced Superconducting Tokamak (EAST), which is an ITER-relevant experimental tokamak would lead to serious plasma-material interactions, wall conditioning must be used to limit impurities release from the wall and tritium inventory retained in the wall. Helicon plasma source is known as efficient generator of uniform and high density plasma. Helicon Wave Plasma (HWP) discharge cleaning was considered as the most promising method for superconducting tokamak. In this paper, HWP cleaning with wave frequency of 13.56 MHz have been performed in presence of permanent toroial magnetic filed (1-2 T) in EAST. Three different antennas were designed for HWP wall conditioning. Influences of working parameters on the HWP cleaning efficiently were investigated. This research is concentrated on experimental study of HWP discharge cleaning, in order to collect more data of wall conditioning and provide science and technology support for the requirement of ITER operation.