Can High Current Density HTS Magnets be Quench Protected Using Methods Used to Protect High Current Density LTS Magnets?

• Published in: IEEE transactions on applied superconductivity Vol. 31; no. 5; pp. 1 - 6
• Main Author: Green, Michael A.
• Format: Journal Article
• Language: English
• Published: New York IEEE 01.08.2021; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Aluminum; CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; Conductors; Copper; Current density; High current; High-temperature superconductors; Internal energy; LTS and HTS magnets; Magnesium compounds; Magnets; of LTS and HTS Magnets; Quench Protection; Solenoids; Superconducting magnets
• ISSN: 1051-8223; 1558-2515
• DOI: 10.1109/TASC.2021.3058203

In the 1970s the Lawrence Berkeley Laboratory (LBL) was testing high current density magnets where the EJ 2 limit was up to two orders of magnitude higher than the quench protection methods of the period would permit at the time. LBL was designing a high current density (J) thin solenoid with a large volume and stored energy (E). The accepted EJ 2 limit at the time was ∼10 23 J A 2 m −4 . In order to exceed the EJ 2 limit by two orders of magnitude, one had to greatly increase the quench protection voltages (V) and magnet current (I). In 1977, LBL tested four quench protection methods on a 2-meter diameter high current density solenoid with a stored energy of 2 MJ. Three of these quench protection methods worked well, but the fourth didn't appear to work. These methods will be discussed as to whether they can be applied to HTS or MgB 2 high current density magnets.