Evaluation of ITER divertor shunts as a synthetic diagnostic for detachment control

Nuclear Fushion

article

C.A. Orrico¹  T. Ravensbergen²  R.A. Pitts²  X. Bonnin²  E. Kaveeva³  J.S. Park⁴  V. Rozhansky³  I. Senichenkov³  C. Watts²  M. de Baar¹ 

[1] Eindhoven University of Technology, Department of Mechanical Engineering, Control Systems Technology Group;ITER Organization;Peter the Great St. Petersburg Polytechnic University;Oak Ridge National Laboratory;Dutch Institute for Fundamental Energy Research

关键词: plasma control;    detachment;    synthetic diagnostics;    divertor;    exhaust;    SOLPS-ITER;   

DOI  :  10.1088/1741-4326/acd947

来源: Institute of Physics Publishing Ltd.

【 摘 要 】

Reliable diagnostics that measure the detached state of the ITER divertor plasma will be necessary to control heat flux to the divertor targets during steady state, burning plasma operation. This paper conducts an initial exploration into the feasibility of the divertor shunt diagnostic as a lightweight, robust, and real-time detachment sensor. This diagnostic is a set of shunt lead pairs that measure the voltage drop along the divertor cassette body, from which the plasma scrape-off layer (SOL) current is calculated. Using SOLPS-ITER simulations for control-relevant ITER plasma scenarios, the thermoelectric current magnitude along the SOL is shown to decrease significantly with the onset of partial detachment at the outer divertor target. Electromagnetic modelling of a simplified divertor cassette is used to develop a control-oriented inductance-resistance circuit model, from which SOL currents can be calculated from shunt pair voltage measurements. The sensitivity and frequency-response of the resulting system indicates that the diagnostic will accurately measure SOL thermoelectric currents during ITER operation. These currents will be a good measure of the detached state of the divertor plasma, making the divertor shunt diagnostic a potentially extremely valuable and physically robust sensor for real-time detachment control.

【 授权许可】

Unknown