TRANSFORMER OPERATION CONTROL APPARATUS AND METHOD FOR SUPPRESSING MAGNETIZING INRUSH CURRENT

摘要

A control portion for a breaker causes the breaker to apply a current of a first apply phase (R phase) at a timing where a residual flux of R phase agrees with a steady magnetic flux. Thereafter, the control portion determines whether or not the current measured by current measuring portions exceeds a threshold value. When the measured current does not exceed the threshold value, the control portion causes the breaker to apply currents of the other two phases (S and T phases) at a timing where a voltage of R phase becomes zero. When the measured current exceeds the threshold value, the control portion causes the breaker to once shut off the current of R phase and to apply again the current of R phase.