| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a stationary power supply device unit for aircrafts, capable of performing protection action by securely detecting an earth fault if the earth fault occurs, while maintaining a power supply state without performing earth fault detection if a loop circuit occurs, when power is supplied by a plurality of constant voltage constant frequency devices (CVCF) to one aircraft. <P>SOLUTION: At least one set of a zero-phase-sequence current transformer 4, and an earth fault over-current relay 5 connected to the zero-phase-sequence current transformer 4, is prepared as a stationary power supply device unit X for aircrafts, which includes a plurality of three-phase four-line stationary power supply devices 1A and 1B for supplying power to an aircraft P under parking. When power is supplied to one aircraft P, all three-phase and neutral phase electric lines 2a, 2b, 2c and 3 of the stationary power supply devices 1A and 1B are connected to a load of the aircraft P, while the electric line 3 of the neutral phase is grounded to a body of the aircraft P, and a ground line 32 of each of the stationary power supply devices 1A and 1B is connected to the same ground electrode G through the common zero-phase-sequence current transformer 4. <P>COPYRIGHT: (C)2012,JPO&INPIT</p> |
