Redesign of the Coils for the 60T Controlled-Waveform Magnet at NHMFL

Journal Article · 22 February 2022 · IEEE Transactions on Applied Superconductivity

DOI: https://doi.org/10.1109/tasc.2022.3151836 · OSTI ID:2290306

Nguyen, Doan Ngoc  ^[1]; Vo, Do Ta ^[1]; Michel, James Raleigh  ^[1]; Dixon, Iain  ^[2]; Akins, Todd ^[2]; Han, Ke  ^[2]

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1. Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)
2. Florida State Univ., Tallahassee, FL (United States). National High Magnetic Field Lab. (MagLab)

Driven by the1.4 GW generator, the 60T Controlled Waveform (60 TCW) magnet was the most powerful controlled waveform system in the world and had always been one of most important magnets to the National High Magnetic Field (NHMFL) and high-field research community because of its following unique features: (1) quasi-static field up to 60 T with 100 ms flat-top and total pulse-length of about 2000 ms, (2) variable magnetic field waveforms such as staircase and triangle with flat-top (3) relative large bore (32 mm) and (4) very fast cooling time (20 minutes) between pulses [Boebinger, 2001], [Crooker et al. 2001]. The magnet is composed of nine concentric coils, with each coil consisting of several conductor winding layers reinforced by a high-strength metallic shell. The magnet underwent a catastrophic failure in 2000 and all the coils had to be rebuilt. In late 2014 the second magnet version failed near the mid-plane of coil 7. The simulations afterward that incident indicated that the overall strength of the coil would be increased by replacing a section of the reinforcing shell with Zylon fiber-epoxy composite. This reduces the stress and thus significantly lowers the level of plastic deformation in the windings. The role of the metal and Zylon fiber reinforcing layers in bearing the axial and radial Lorentz forces has been studied to optimize the magnet design. Here, the results of the optimization will be discussed as well as challenges that have been presented in rebuilding the individual coils of the magnet.

• Research Organization: Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)
• Sponsoring Organization: USDOE National Nuclear Security Administration (NNSA); National Science Foundation (NSF)
• Grant/Contract Number: 89233218CNA000001
• OSTI ID: 2290306
• Report Number(s): LA-UR--22-20354; {"","Journal ID: ISSN 1051-8223"}
• Journal Information: IEEE Transactions on Applied Superconductivity, Journal Name: IEEE Transactions on Applied Superconductivity Journal Issue: 6 Vol. 32; ISSN 1051-8223
• Publisher: IEEECopyright Statement
• Country of Publication: United States
• Language: English