Multi-Mode Error Field Correction on the DIII-D Tokamak

摘要

Error field optimization on DIII-D tokamak plasma discharges has routinely been done for the last ten years with the use of the eternal 'n=1 coil' or the 'C-coil'. The optimum level of correction coil current is determined by the ability to avoid the locked mode instability and access previously unstable parameter space at low densities. The locked mode typically has toroidal and poloidal mode numbers n=1 and m=2, respectively and it is this component that initially determined the correction coil current and phase.