DEVICE FOR DETECTING OPEN PHASE OF CONNECTION LINE OF NUCLEAR POWER PLANT AND OPEN PHASE DETECTING METHOD THEREFOR

摘要

Disclosed are a device for detecting an open phase of a connection line of a nuclear power plant and an open phase detecting method therefor. The open phase detecting device, according to the present invention, has a zero-phase current transformer provided at a neutral wire of a Y-connection on a primary side of a transformer used for the nuclear power plant, and determines that the open phase has occurred in the transformer when an actual value of a zero-phase current induced into the zero-phase current transformer is maintained at a pre-set reference value or higher for a pre-set reference time or more. The detecting device of the present invention generates an alert and provides the same to a main controller (30) so as to allow an administrator to take appropriate measures or to stop the operation of the transformer by opening a circuit breaker on a secondary side of the transformer when it is has been determined there is an open phase.