EXCITATION INRUSH CURRENT SUPPRESSION DEVICE

摘要

PROBLEM TO BE SOLVED: To provide an excitation inrush current suppression device capable of calculating a residual magnetic flux of a three-phase transformer with accuracy, and suppressing an excitation inrush current.;SOLUTION: An excitation inrush current suppression device 10 has: a voltage measurement part 1 measuring respective phase voltages of a transformer 23 and system voltages of respective phases; an effective blocking timing calculation part 2 calculating an effective blocking timing when instantaneous values of all three phases of the respective phase voltages are converged into zero; an iron core magnetic flux calculation part 3 integrating the phase voltages respectively to calculate magnetic fluxes of the respective phases of an iron core of the transformer 23; an effective residual magnetic flux calculation part 4 calculating effective residual magnetic fluxes of the respective phases by using the magnetic fluxes of the respective phases at the effective blocking timing among the magnetic fluxes of the respective phases as the effective residual magnetic flux; a closing phase angle calculation part 5 calculating a closing phase angle to a system side circuit breaker 21 on the basis of the effective residual magnetic fluxes of the respective phases; and a closing phase angle controller 6 closing the system side circuit breaker 21 on the basis of the system voltages of respective phases and the closing phase angle.;COPYRIGHT: (C)2013,JPO&INPIT