| 摘要 |
PURPOSE:To obstruct the abnormal operation of this device, by effectively detecting quenching even when this device is driven for a long time in the very limit rated voltage by detecting quenching from the calorific power of this superconductive coil. CONSTITUTION:A current shunt circuit 6 for detecting the quantity of conductive currents supplied to a superconductive coil 1 from a power source 3 is inserted in series between a circuit breaker 2 and the superconductive coil 1, and the detecting value is fed to a signal processing circuit 5. Currents i(t) supplied to the superconductive coil and generated voltage v(t) detected from both ends of the coil are each integrated in the signal processing circuit 5, said integrated value in a fixed period t1-t2 is multiplied and detecting value P that is the object of the detection of quenching is obtained. The value is compared with two set points P1, P2 (P1< P2) decided in response to calorific power, alarms are given when P>=P1, and the circuit breaker 2 is energized and the supply of power to the coil is obstructed when P>=P2. |
