Advanced magnetic diagnostic coils based on TPC technology for COMPASS-U and EU-DEMO

Abstract

Magnetic diagnostic coils based on Thick Printed Copper (TPC) technology for COMPASS-U and EU-DEMO fusion reactors are introduced in this paper. Special emphasis is placed on the aspects of design and technology qualification. Firstly, the results of the tests carried out to qualify the TPC technology for the Tokamak environment are presented. Dedicated test samples were designed and temperature cycling irradiation and adhesion tests including electrical parameters measurements were executed. The aim of the TPC coil design was to achieve a high effective sensor area (up to 0.25 m2) and small dimensions compared to conventional coils. The coils can be composed from materials as Cu and Al2O3, AlN, or spinel (Al2MgO4) which ensures compatibility with elevated temperatures (at least 500 degrees C) and intense neutron radiation. Two coil variants, 1st with low winding density and 2nd with high winding density are proposed. Advanced layout of high-density coil winding achieving high suppression factor of cross-field sensitivity is presented. In parallel, the winding layout is also optimized to reduce parasitic radiation and temperature gradient induced side effects. Preliminary results of irradiation tests and temperature cycling test of TPC low winding density coil are presented.