| 摘要 |
<p>A superconducting system having a superconductive coil (1) and a perpetual current switch (3) connected in parallel therewith, and constituted by a superconductive lead (4) and a heater (5) that causes the superconductive lead to be normal-conductive. Both of these are incorporated in a cryogenic vessel (9). A DC power source (2) has a variable output for circulating a current of a specified amount within a closed loop constituted by the superconductive coil (1) and the superconductive lead (4) so as to create a perpetual current loop. A reference generator unit (16) is provided with a current reference value that has a first sweep gradient, for changing the superconductive coil current, an established current value for causing the superconductive coil current to reach specified target value, a current reference value that has a second sweep gradient and does not change the superconductive coil current after the arrival thereof at the target value but changes the current that flows from the DC power source (2) into superconductive lead (4). A timing control unit switches with specified changeover timings (17) the two current reference values supplied to the reference generator (16), and the heater- energising periods.</p> |
