Power switching control device and closing control method thereof

摘要

A power switching control device and a closing control method thereof that can suppress generation of a transient voltage or current that is possibly caused by a variation in a load-side voltage after interrupting a current are obtained. A circuit-breaker-gap-voltage estimate value at and after a present time is calculated based on a power-supply-side voltage estimate value and a load-side voltage estimate value at and after the present time, a target closing-time domain from a closing controllable time to a closing control limit time in which a circuit breaker can be closed at a timing when an absolute value of the circuit-breaker-gap-voltage estimate value falls within a preset allowable range is calculated based on this circuit-breaker-gap-voltage estimate value, and the closing controllable time is delayed by a preset delay time in a case of a subsequent closing phase of a second or later closing phase.

主权项

1. A power switching control device comprising:
a voltage measurement unit that measures a power-supply side voltage an a load-side voltage of a circuit breaker; a voltage estimation unit that estimates a power-supply-side voltage estimate value at and after a present time based on the power-supply side voltage for a period of a past constant time, and that estimates a load-side voltage estimate value at and after the present time based on the load-side voltage for the period of the past certain time; a target closing-time calculation unit that calculates a circuit-breaker-gap-voltage estimate value at and after the present time based on the power-supply-side voltage estimate value and the load-side voltage estimate value, that determines a closing order, and that calculates a target closing-time domain from a closing controllable time to a closing control limit time based on the circuit-breaker-gap-voltage estimate value and the closing order, the target closing-time domain being a time domain in which the circuit breaker can be closed at a timing when an absolute value of the circuit-breaker-gap-voltage estimate value falls within a preset allowable range; and a closing control unit that controls the circuit breaker to be closed in the target closing-time domain, wherein the target closing-time calculation unit delays the closing controllable time by a preset predetermined delay time in expectation of a variation in a circuit-breaker gap voltage due to closing of the circuit breaker in a preceding closing phase in a case where the closing order is a subsequent closing phase that is a second or later closing phase when calculating the target closing-time domain.