Final development and preliminary experiment progress of in-vessel resonant magnetic perturbation coils system on HL-3 tokamak

This paper details the design, construction, and analysis of resonant magnetic perturbation (RMP) with 16 in-vessel coils on the HL-3 to investigate the interactions between resonant magnetic perturbations and magnetohydrodynamic instabilities. The toroidal × poloidal = 8 × 2 arrangement allows for a more flexible magnetic field and spectrum shape. The RMP coil was designed as a four-turn double-layer winding. The coils are adopted with a water-cooled hollow copper conductor insulated with a MgO layer and then housed inside a welded stainless steel shell. The thermal and electromagnetic loads of the coil were evaluated by simulation, which meets the requirements. Four power supplies are integrated into the HL-3 system that can provide DC and AC with various waveforms. The maximum DC amplitude is 3 kA, while the AC frequency can reach up to 1 kHz. In the HL-3 H-mode plasmas, an experimental result of edge localized mode (ELM) mitigation with n = 1 RMPs which are oddly paired by 8 RMP coils is also given for the first time in this paper.