SEMINAIRE D'ARNAUD DEVRED (ITER ORGANIZATION)
Section Leader & Magnet Division Deputy
Superconductor Systems & Auxiliaries Section
Superconductors and Magnets for ITER
The ITER magnet system is the largest and most sophisticated magnet system ever designed. It includes 18 toroidal field (TF) coils, 6 poloidal field (PF) coils, a (CS) central solenoid made up of 6 independently-powered modules and 9 pairs of correction coils (CC), which are superconducting and supplied by 31 feeders and 40 pairs of high temperature superconductor (HTS) current leads. In addition, it includes 2 ring-type, vertical stability (VS) coils and 3 sets of 9 edge localized modes (ELM) coils, which are normal conducting and attached via rails to the inner wall of the vacuum vessel. The superconducting coils are wound from Cable-In-Conduit Conductors (CICC) made up of a mix of Nb–Ti or Nb3Sn strands and copper strands, assembled into a rope-type cable that is inserted into a conduit of butt-welded austenitic steel tubes through which is circulated a flow of supercritical helium. The conductors for the in-vessel coils are water cooled and made up of single-lengths of high purity copper tubes surrounded by magnesium oxide insulation and also inserted into a conduit of butt-welded austenitic steel tubes. Superconductors, TF, PF, CS, correction coils and feeders are contributed in-kind by 6 out of 7 ITER partners (CN, EU, JA, KO, RF and US) while the magnet instrumentation and in-vessel coils are direct fund procurements by the ITER Organization.
More than 20 years after its inception, ITER is well into the manufacturing phase and industrial contracts for the in-kind contributions of its components are underway. Over 90% of conductor unit lengths have been manufactured and accepted. Winding is well underway for TF coils and CS modules and has started for PF and correction coils. HTS current lead prototypes of all types have been successfully qualified and feeder component production has been launched. Main magnet instrumentation contracts have been placed and are running. In-vessel coils have been redesigned, aiming at more robustness and reliability and preparation work for magnet assembly has been initiated with the development of Assembly and Inspection Plans and the production of mock-ups at Magnet Infrastructure Facility for ITER (MIFI) at CEA/Cadarache.