A new upper divertor with internal coils for ASDEX upgrade – Status of the project

ASDEX Upgrade is a tokamak that can be operated with the strike lines in the upper and/or the lower divertor. In 2016 a project was started to develop and install a new upper divertor with internal coils and an in-vessel cryo-pump. The aim is to investigate alternative magnetic configurations that may facilitate the access to detachment via an enhanced poloidal flux tube expansion and/or connection length. To realize the envisaged magnetic configurations two internal coils operated with up to 52 kAt will be installed near the upper outer strike line. Since the conceptual design was presented critical aspects of the project were identified and investigated in detail. These are the vessel integration, the coil concept, the forces, in particular during disruptions, an intrinsic safe power supply, the cryo-pump and last but not least, operation with co and counter magnetic field. The present status of each of the components is presented in the paper.