Real-Time Distributed Quench Detection In High Temperature Superconductor Magnets

Nuclear fusion has great potential for supplying global energy needs with a clean, abundant energy source. Advanced superconducting magnets will be used to contain the plasma at the center of the reactor. To operate these magnets, new sensors are needed to monitor the superconductors in real-time to detect the signs that the superconductor may quench (lose superconducting properties), so that corrective action can be taken. Luna and Pennsylvania State University (Penn State) are developing an innovative distributed fiber optic sensor to actively measure the temperature along a superconductor to detect a quench event before it occurs. Luna’s core technology lies in Optical Frequency Domain Reflectometry (OFDR), which uses the Rayleigh backscatter fingerprint within an optical fiber as mechanism to monitor temperature or strain, with no dead zones or gaps. Dr. Justin Schwartz and his group at Penn State have experience using Luna’s sensing technology for quench event detection in short lengths of high temperature superconductors. Luna and Penn State will increase the sensing length and improve the sensor integration to bring this technology out of the laboratory and into operating superconductor magnets. During the Phase II effort, Luna and Penn State will build on the successes achieved during Phase I by integrating the recently developed optical networks and data processing algorithms into the commercial ODiSI-6100 platform. This will extend the sensing length while maintaining a sufficiently high update rate and data quality, both of which are needed for quench detection. Penn State will continue to investigate potential sensor routing methods within the superconductor for effective temperature measurement, fabricate a prototype, and develop quench mitigation algorithms utilizing Luna’s new sensing modes. Luna and Penn State will experimentally validate the technology through a demonstration of its ability to sense the temperature changes associated with a quench event. The sensing technology developed on this project will be directly applicable to superconductor magnets found in fusion reactors, high-energy physics experiments, particle accelerators, and naval ship degaussing coils. The increased sensing lengths and faster update rates developed on this project will also be integrated with Luna’s existing strain and temperature sensing product line to increase the use cases and application space for those products.