The first implementation of active detachment feedback control in EAST PCS

摘要

EAST achieved 101.2 seconds H-mode discharge with total power injection up to 3MW in 2017. Consequently to the enhanced auxiliary heating power, the active divertor heat flux control is urgently needed in EAST. In 2018, the active divertor detachment feedback control was implemented successfully in EAST plasma control system (PCS) with divertor Langmuir probe measurements for evaluating the divertor particle flux. The control algorithm controlled the degree of detachment effectively during the 2018 EAST experiments through either D-2 fueling in the low field side using SMBI or impurity seeding from the divertor volume in H-mode plasmas, without significant degradation of the core-plasma performance, i.e., exhibiting good core-edge-divertor integration. The algorithm implementation in PCS and experimental results will be reported in this paper. Further efforts will be made to extend active feedback control towards long-pulse H-mode detachment maintenance in the near future, which will benefit the high power, H-mode operation for ITER.