APPARATUS AND METHOD FOR COMPRESSING EXCITING INRUSH CURRENT OF TRANSFORMER

摘要

To suppress, without additionally providing any interrupters having resistors or the like, an exciting inrush current occurring when a three-phase transformer is powered on by using three single-phase type interrupters at the same time or using a three-phase common operating mechanism type interrupter. In a transformer exciting inrush current suppressing method for suppressing an exciting inrush current occurring at the beginning of an excitation by coupling the phase terminals of a three-phase transformer (300) to a three-phase power supply (100) via three-phase interrupters (200), the phase voltages of a primary, secondary or tertiary side or the interline voltages during steady-state application of three-phase AC voltages to the transformer (300) are integrated to calculate steady-state magnetic fluxes (4,5,6) of the transformer phases; the polarities and magnitudes of residual magnetic fluxes (7,8,9) of the transformer phases after the interruption of the transformer by the interrupters (200) are calculated; and the three-phase interrupters are simultaneously closed when the phases, for which the polarities of the steady-state magnetic fluxes (4,5,6) of the transformer phases are identical with the polarities of the residual magnetic fluxes (7,8,9) of the transformer phases, are within a range (13) in which the three phases overlap with one another.