A peer-reviewed paper detailing the Jingtian magnet, titled “21.7-tesla large-scale high-temperature superconducting toroidal magnet for tokamak fusion application,” was recently published in IEEE Transactions on Applied Superconductivity （IEEE TAS). The paper presents the design, fabrication, and performance testing of this large-scale magnet, which features a D-shaped winding pack comprising 32 modular Rare-Earth Barium Copper Oxide (ReBCO) pancake coils.
Operating at 5K with supercritical helium cooling, the Jingtian magnet achieved a record-breaking peak magneticfield of 21.7 T, the highest reported for any all-HTS tokamak magnet. Steady-state operation at 24.3 kA confirmed its structural integrity, cryogenic cooling efficiency, and consistency with magnetic field modeling predictions. The primary mission of Jingtian magnet is to research, develop, and validate the critical technologies and manufacturing techniques essential for the toroidal field (TF) magnets of our next-generation HH170 HTS tokamak, a 10 times energy gain fusion device. This success not only provides critical validation data for the HH170 design but also establishes a foundational milestone for the engineering application of high-field compact tokamaks, demonstrating significant potential to reduce fusion reactor size and cost.
DOI: 10.1109/TASC.2025.3573869