| 摘要 |
PURPOSE:To protect a superconducting winding and a permanent current switch in transfer to normal conduction. CONSTITUTION:A protective circuit contains an exciting power supply 3 for supplying the exciting current to the superconducting coil 1 of a superconducting magnet through a switch 2; and a permanent current switch 4, a thermal switch, in parallel with the coil 1. The permanent current switch 4 is provided with a power supply 7 for a heater 6 wound around a superconductor 5, and its switching operation depends on the on/off state of the heater 6. The superconducting coil 1 is divided into a plurality of portions, and a protective resistor 9 of a high resistance R1 is connected to each of the portions in parallel. In addition, a protective resistor 10 of a low resistance R2 is connected to the whole of the coil 1 in parallel. |
