The global energy balance of the ASDEX Upgrade tokamak determined with the revised cooling water calorimetry

Abstract

An extensive analysis of the global energy balance on the ASDEX Upgrade (AUG) tokamak has been performed. For such a purpose a complete revamping of the AUG cooling water calorimetry originally described in (Richter and Vernickel 1994 Rev. Sci. Instrum.65 5) has been done. The system, which has been largely improved, consists of 88 cooling units, which provides an almost perfect toroidal and poloidal coverage of the in-vessel components of the AUG tokamak. To measure the energy loss due to radiation, which is only partially captured by the cooling water calorimetry, a novel framework is introduced to calculate the losses utilizing bolometric data. The analysis of the global energy balance based on almost 600 discharges reveal the remarkable capability to account more than 95% of the total injected energy on average.