PROTECTIVE RELAY DEVICE AND CURRENT DIFFERENTIAL PROTECTIVE RELAY DEVICE

摘要

PROBLEM TO BE SOLVED: To provide a protective relay device and a current differential protective relay device adaptable to the future development (migration) of a communication infrastructure.;SOLUTION: The protective relay device includes an input unit that is input with the current of a power transmission line and converts it into a digital quantity; a timing control unit that determines sampling timing at the input unit; a computation unit that carries out protective computation using a digital quantity from the input unit; an output unit that supplies a control signal for a circuit breaker provided in the power transmission line, according to the result of computation by the computation unit; an internal communication unit that carries out data transmission to transmit a digital quantity at the input unit by cyclic packet forwarding and receives data transmitted by cyclic packet forwarding and supplies it to the computation unit; and a selection unit that is input with a first sampling pulse for sampling synchronization control at the internal communication unit, and a second sampling pulse for sampling synchronization control from an external communication unit and selects either sampling pulse to supply it to the timing control unit.;COPYRIGHT: (C)2011,JPO&INPIT