In recent years, Tokamak Energy has completed a series of demonstration projects on a rapid development timescale to generate stable and robust high temperature superconducting magnets, experimental test capabilities, and sophisticated simulation tools.
Through these successes, Tokamak Energy has optimised the design of a full spherical tokamak HTS magnet system demonstrator “Demo4”. The system will comprise 14 toroidal field (TF) limbs and a pair of poloidal field (PF) coils, and will be operated at a fusion-relevant temperature of 20 K (minus 253 C))
Each TF limb is 0.8m in linear dimension, containing an HTS double pancake coil wound with non-twisted stacked tape cable and a novel partially insulated construction – a tuned turn-to-turn resistivity.
The PF coil pair is 1.5m in diameter and has a fully insulated construction, enabling operation in a fusion-relevant DC + AC modulated condition. The magnet makes use of >50 km of full-width REBCO HTS procured from four key manufacturers. The system will raise the technology readiness level of HTS magnets for fusion and other applications in several key areas including: HTS coil manufacturing methodologies; full system interactions; coil stress management and stored energy management. The system is in construction now, and plans are underway for test in 2022.
Dr Greg Brittles, Senior HTS Magnet Engineer will present a technical overview of the magnet system and the progress made towards the construction of this challenging and important demonstrator at this year’s Magnet Technology Conference in Fukuoka, Japan and online on Wednesday 17th November.