Title :
R&D of superconductors for 70 MW class generators
Author :
Chibe, H. ; Uno, Naoki ; Ichikawa, Tatsumi ; Meguro, S. ; Takahashi, K. ; Saitou, T. ; Sakai, S. ; Akita, S.
Author_Institution :
Super-GM, Osaka, Japan
fDate :
7/1/1996 12:00:00 AM
Abstract :
Super-GM has been developing 70 MW class superconducting generators (model machines) for a 200 MW class pilot generator. Three types of NbTi conductors were developed for each of three model machines. Regarding the high stability type conductors, residual resistance value of 6.5 μΩ/m was achieved by adopting an Al stabilizer. Regarding the high current density type, Ic of 13.8 kA at 5 T was realized by reducing void fraction in conductors and maintaining high residual resistivity ratio. For the low AC loss type, high Jc and low AC loss (8.1 kW/m3) have been succeeded by applying strand insulation and two stage cabling. To confirm superconducting characteristics concerning long-term reliability, Ic and AC loss of each conductor were measured under 10000 times repeated compressive force of 30 MPa that is supposed in daily start and stop operation of a generator for 30 years. In parallel to the R and D of NbTi conductors, R and D of Nb3Sn conductors were also conducted for enhancement of critical current density and critical magnetic field
Keywords :
AC generators; critical current density (superconductivity); electrical conductivity; magnetic fields; niobium alloys; research and development management; stability; superconducting machines; tin alloys; titanium alloys; voids (solid); 13.8 kA; 200 MW; 30 MPa; 5 T; 70 MW; Al; Nb3Sn; Nb3Sn conductors; NbTi; NbTi conductors; R&D; compressive force; critical current density; critical magnetic field; high current density; high residual resistivity ratio; high stability type conductors; long-term reliability; residual resistance; strand insulation; superconducting generators; superconductors; two stage cabling; void fraction reduction; Conductors; Current density; Force measurement; Niobium compounds; Research and development; Stability; Superconducting cables; Superconducting integrated circuits; Superconductivity; Titanium compounds;
Journal_Title :
Magnetics, IEEE Transactions on
