High temperature superconductors (HTS) are excellent technology for creating high field magnets of 10 T or greater, however they are rarely used to create magnets that must also ramp the magnetic field at high rates. This is due to transient loss mechanisms under changing magnetic fields that are a characteristic of high temperature superconductors.
A critical application for high ramping magnetic fields is in the characterization of new rare-earth permanent magnet materials, which are essential for reducing the cost, improving the supply chain security for electric transportation and industry, and reducing CO2 emission. Our hypothesis is that, using HTS wires, we can develop high-field, fast-cycling, large -bore, and small fringe-field magnets as test instruments for industry usage. Target magnet specifications will be:
1. High field: ~ 10 T
2. Rapid-cycling: 1 minute for full-cycle (40 T/min), 80 times faster than LTS magnets
3. Large sample bore: > 35 mm, suitable for industry usage
4. Low fringe fields by using high permeability carbon steel: no interference in surrounding instruments
We have a three-year project to design 10 T fast-ramping HTS magnets for characterizing new rare-earth permanent magnet materials. In this talk, the detailed project plan will be introduced and some initial numerical and experimental results on AC loss of a sub-scale coil winding will be presented.
This work was supported in “Fast-ramping superconducting magnets” funded by US Office of Naval Research under Grant award No. N629092412037.
Keywords: Fast ramping magnet, AC loss, rare-earth materials