Speaker
Description
The 32 T all-superconducting magnet of the National High Magnetic Field Laboratory was successfully tested in December 2017 and it is expected to be available for users in 2019. This all-superconducting magnet, comprised of two HTS inner coils and five outer LTS coils, is the first superconducting magnet above 30 T and some 8 T beyond the current strongest superconducting magnet in use as a science instrument. One of the challenges facing this new magnet technology is the estimation of the screening currents, and the corresponding hysteresis losses in the two insert coils. These coils are made of more than 20,000 turns of insulated REBCO conductor connected in series. The modelling of such system is complicated due to the computational load. Up to now, only medium size magnets (a few thousands of tapes) have been successfully modelled with methods based on the H formulation of the Maxwell’s equations and the use of the Finite Element Method. In the present work, we propose a new model based on the T-A formulation of the Maxwell’s equations implementing a homogeneous technique to address efficiently the estimation of the current density distributions HTS insert coils. This new method allows modelling large-scale systems on personal computers with a low computation time and memory usage.
