Method for Reinforcement, Quench Protection, and Stabilization of Large All-Metal Superconducting Magnets [PPPL No. M-1054]

Web Published:

Non-Confidential Brief

Method for Reinforcement, Quench Protection, and Stabilization of Large All-Metal Superconducting Magnets

Princeton Docket # 24-4066-1


Inventors at the Princeton Plasma Physics Laboratory (PPPL) have developed a novel technology with significant advantages in the design and protection of high temperature superconducting (HTS) coils.

The primary existing method of quench detection of HTS coils uses fiber optics. Due to the extremely slow normal zone propagation speed in yttrium barium copper oxide (YBCO) tape and other high temperature superconductors, the fiber optic sensor must be built into the coil winding pack. This significantly compromises the coil winding pack mechanical and structural integrity. Additionally, traditional methods of stabilizing superconducting coils involve the use of insulators such as glass tape and epoxy. This approach of insulating and fabricating coils is error-prone and challenging for large high magnetic field coils, especially those with complex geometry, and can limit their radiation tolerance in next-step fusion systems. 

Compared to these traditional designs, the configuration of the design of this invention offers significant advantages in the protection and design of high temperature superconducting magnets. Its unique design ensures quick and uniform energy extraction during a quench event as well as increased radiation tolerance, current density, and structural integrity of the coil winding pack.


  • Fusion energy research and development
  • NMR & MRI conduction cooled HTS magnets
  • Large scale magnetic shields


  • Protection of HTS coils from quench damage
  • Increased radiation tolerance
  • Error-free fabrication with reduced cost
  • Higher winding pack and current density



Michael Zarnstorff is Chief Scientist at PPPL, where he oversees research that ranges from testing ideas for harnessing fusion to developing rockets for space flight. His job encompasses keeping projects aligned with DOE goals and envisioning new research opportunities for PPPL. An award-winning physicist and a co-discoverer of the bootstrap current in magnetically confined fusion plasmas, he joined PPPL in 1984 and was Deputy Director for Research from 2009 to 2019. 

Yuhu Zhai is the head of the PPPL superconducting magnet program and lead engineer for the NSTX-U recovery project.


Intellectual Property Status

Princeton is currently seeking commercial partners for the further development and commercialization of this opportunity.



Tony Williams

Princeton University Office of Technology Licensing • (609) 258-3769 •

Laurie Bagley

Princeton Plasma Physics Laboratory • (609) 243-2425 •


Patent Information:
For Information, Contact:
Tony Williams
Associate Director
Princeton University
Michael Zarnstorff
Yuhu Zhai