Stability in a long length NbTi CICC

• Published in: IEEE transactions on applied superconductivity 2001-03, Vol.11 (1), p.1542-1545
• Main Authors: Bottura, L., Ciotti, M., Gislon, P., Spadoni, M., Bellucci, P., Muzzi, L., Turtu, S., Catitti, A., Chiarelli, S., della Corte, A., Di Ferdinando, E.
• Format: Article
• Language: English
• Subjects: Applied sciences; Coiling; Conductors; Conductors (devices); Controled nuclear fusion plants; Electrical engineering. Electrical power engineering; Electromagnets; Energy; Energy. Thermal use of fuels; Exact sciences and technology; Fusion reactor design; Installations for energy generation and conversion: thermal and electrical energy; Magnetic field measurement; Magnetic fields; Modules; Niobium base alloys; Niobium compounds; Plasma simulation; Plasma temperature; Pulse measurements; Spreads; Stability; Studies; Superconducting coils; Superconductivity; Titanium compounds; Various equipment and components
• ISSN: 1051-8223; 1558-2515
• DOI: 10.1109/77.920070

A crucial issue for a superconducting coil in order to be safely used in the magnetic system of a fusion reactor is stability against all foreseen disturbances. To simulate the fusion machine conditions, including off-normal events, e.g. plasma disruptions, the energy deposition has to be spread over a "long length" cable in conduit conductor (CICC) and a background magnetic field is needed. We have therefore designed and built an experiment consisting of an instrumented NbTi test module inserted in a pair of co-axial pulsed copper coils. A 0.6 m diameter superconducting coil provides a background magnetic field up to 3 T. Calibration of the energy inductively coupled between the pulsed coils and the module has been obtained measuring the system temperature increase just after the pulse by means of thermometers positioned along the conductor. Stability vs. operating current I/sub op/ has been examined for different helium temperatures and different background magnetic fields. The finite element code Gandalf for the stability and quenching transients analysis in forced flow cooled superconducting coils has been run to check the matching with the experimental results.