A 2.5 T/100kVA a.c. superconducting magnet has been developed using Nb-Ti superconducting wire with artificially introduced pins. Investigations have been conducted regarding the suitability of critical current density Jc design using artificial pins and the effectiveness of magnets using wires with high Jc. Studies on pin design suggested that the maximum pinning force density Fp would be reached at a magnetic field of 2.5 T. As anticipated, the maximum Fp was achieved at 2.5T, and a high Jc of 4.7 × 109 A m-2 was obtained. Using an a.c. magnet fabricated from this wire, current operation at 60 Hz and 4.2 K was effected, and steady state operation at a capacity of 104.8 kVA, a current of 105.8 Arms and a voltage of 991.2 Vrms was achieved. At the same time, a central magnetic field of 2.5 T was obtained. In addition, it was demonstrated that the total a.c. losses were 4.8 W at a central magnetic field amplitude B0 of 2 T, a mere 0.007% with respect to the capacity of 69 kVA and much lower than in a.c. magnets of the 100 kVA class made using conventional a.c. wires. This confirmed the effectiveness of reducing magnet size through the use of wires having high current density.
All Science Journal Classification (ASJC) codes
- Materials Science(all)
- Physics and Astronomy(all)