M. Iwakuma et al., Development of a 1T cryocooler-cooled pulse coil with a Bi2223 superconducting parallel conductor for SMES, IEEE APPL S, 9(2), 1999, pp. 928-931
We designed and fabricated a 1T cryocooler-cooled pulse coil operating at 4
0 K. A 4-strand interlayer-transposed parallel conductor composed of Bi2223
rectangular cross-sectional multifilamentary wires was adopted to realize
a uniform current distribution and to reduce the ac loss density down to th
e level of that of a single strand. The pulse coil is a 16-layer solenoidal
one with an inner diameter of 52 mm, an outer diameter of 111 mm and a hei
ght of 120 mm, The heat drains of AIN plates, which are insulators, are arr
anged between layers for the cooling of the heat due to the sc loss by heat
conduction. We could continuously operate the coil in a triangular wavefor
m mode with an amplitude of 1T and a frequency of 1 Hz. The ac loss was 10.
6 W and the other thermal load was 13 W.