| 摘要 |
PURPOSE:To provide a high-speed reclosing grounding device which, even if a ground fault is followed by another one occuring in another phase while it is being operated to open a circuit in the phase of the fault, can surely cut off induced current in the phase of the fault and allows a circuit breaker to reclose the circuit at high speed thereafter. CONSTITUTION:While a high-speed reclosing grounding device HSES is being operated to open a circuit in the phase of a fault, if a subsequent ground fault in another phase is detected at a transmission line protection relay Ry, this command of detection is transmitted to an operation control unit 10 for the operating phase. A command to close the circuit is immediately output from an output portion 8 only when the command of detection is within the operation holding time of a time holding timer 6 and when the requirements for AND with respect to an already input command to close the circuit are met. To the grounding device which is thus reclosed, a command to open it is output again after a predetermined period of time set by a timer working after the lapse of specified time 10c. Since the subsequent ground fault in the other phase is solved at that point of time, the induced current in the phase of the fault can be cut off by use of the current zero point. |
