Physics (Internal)

High-field superconducting magnet technology for SPARC, a compact net-energy fusion tokamak

This event is part of the Physics Department Colloquia Series.

Large-scale high temperature superconductor (HTS) magnets that exceed 20 tesla offer an accelerated path to commercial fusion energy in the 2030s. However, in a high-field fusion device, magnets must survive extreme mechanical, electrical, and thermal conditions and possess simple, low-resistance, and manufacturable electrical joints, high thermal stability, and robust strategies to handle thermal runaway quench events. Furthermore, the technology to solve these challenges must be qualified at the scale and maturity necessary to begin rapid manufacturing of magnets to meet aggressive timelines. Since 2018, the MIT Plasma Science and Fusion Center and Commonwealth Fusion Systems have jointly been developing high-field HTS magnet technology for SPARC, a compact fusion tokamak seeking to generate >50 megawatts of fusion power with a gain factor of >2 in the mid 2020s. This seminar will provide an overview of (1) the SPARC tokamak and the underlying physics motivating the high-field approach; (2) demonstration of 50 to 100 kiloamp class HTS superconducting cables for large-scale magnets; and (3) the SPARC Toroidal Field Model Coil, the largest HTS magnet to date by several orders of magnitude that will demonstrate 20 tesla operation in the summer of 2021.