| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To prevent magnetic field attenuation during operation in a permanent current mode and suppress heating in a connection part between a permanent current switch and a superconducting coil to minimize the rise of superconducting coil-cooling temperature in a current supply mode. <P>SOLUTION: The refrigerator-cooled superconducting magnet J includes: the superconducting coil 2; the permanent current switch 1 switching between the permanent current mode and the current supply mode; first and second ultracold refrigerators 3 and 4 cooling the superconducting coil 2 and the permanent current switch 1, respectively; and a vacuum vessel 10 storing cooling stages 31, 32, 41 and 42 of the superconducting coil 2, the permanent current switch 1 and the first and second ultracold refrigerators 3 and 4. The magnet further includes: a superconducting wire 5 connecting the superconducting coil 2 to the permanent current switch 1; and a superconducting bypass wire 6 electrically connected to the superconducting wire 5 in parallel thereto along the longitudinal direction. The superconducting critical temperature of the superconducting bypass wire 6 is higher than that of the permanent current switch 1. <P>COPYRIGHT: (C)2011,JPO&INPIT</p> |
