Title :
A large scale approach of bulk HTS to the electric utility area
Author :
Werfel, F.N. ; Flogel-Delor, U. ; Wippich, D. ; Rothfeld, R.
Author_Institution :
Adelwitz Technologiezentrum GmbH, Germany
fDate :
6/1/1999 12:00:00 AM
Abstract :
On the basis of a novel industrial-like YBCO seedless functional melt texture grain alignment process, various HTS devices for superconducting magnetic bearings (SMB) and high-current leads for transport and limiting purposes are fabricated. Critical shielding currents of 30 kA/cm/sup 2/ at 77 K are utilized to construct radial-passive magnetic bearings for 20 kg loads or to suspend and spin a O 4 cm rotor safely to 120000 rpm. Stiffnesses between 40 to 140 N/mm are measured. Multi-grain YBCO rods up to 20 cm length are tested for more than 6 kA/cm/sup 2/ transport currents. The connections to the copper braids are improved to less than 0.4 micro-ohm at 1000 Amperes and 77 K. The experiments show the practical potential of melt textured YBCO with macroscopic orientation of the grain structure for electric power purposes.
Keywords :
barium compounds; critical currents; crystal microstructure; high-temperature superconductors; machine bearings; magnetic bearings; melt texturing; rotors; superconducting cables; superconducting machines; superconducting magnets; yttrium compounds; 0 to 20 cm; 1000 A; 20 kg; 77 K; YBaCuO; bulk HTS; critical shielding currents; electric utility area; grain structure; high temperature superconductors; high-current leads; large scale approach; melt texturing; radial-passive magnetic bearings; rotor; seedless functional melt texture grain alignment; superconducting magnetic bearings; transport currents; Conducting materials; Critical current; High temperature superconductors; Large-scale systems; Magnetic levitation; Magnetic materials; Superconducting magnets; Superconducting materials; Thermal conductivity; Yttrium barium copper oxide;
Journal_Title :
Applied Superconductivity, IEEE Transactions on
