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 I effort, Luna and Penn State will investigate the feasibility of these fiber optic sensors. Luna will develop new optical networks and data processing algorithms to extend the sensing length while maintaining a sufficiently high update rate. Penn State will investigate potential sensor routing methods within the superconductor for effective temperature measurement and fabricate a prototype. 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.