Alternating current feeding circuit breakdown selective relay null for electric railway

摘要

PURPOSE: To provide an AC feeder-circuit failure selective relay, for an electric railway in which a failure can be detected quickly and surely even when the failure of a feeder circuit occurs during regenerative braking of a vehicle for performing AC regeneration. ;CONSTITUTION: A CPU15 operates data from an analog-digital conversion circuit 14 on the basis of a program stored beforehand, detects the change of the feeding current of first and second feeder circuits as vector quantity, and outputs an interruption command for interrupting the first or second feeder circuit when the absolute value of the vector quantity is higher than a predetermined value. DSP16 conducts an operation requiring time at high speed on the basis of a command from the CPU15 to assist the CPU15. A relay 17 operates, e.g. a circuit breaker for opening the first or second feeder circuit on the basis of a command from the CPU15. A display part 18 displays various set points, operating state of the relay part 17, etc., on the basis of a command from the CPU15.;COPYRIGHT: (C)1994,JPO&Japio