Patent ID: 7746080
Filing Date: 2010-06-29
Classification: G01R

Abstract:
1. A method for determining a position of a single phase fault to ground in a feeder line, the feeder line electrically connected to an electrical substation via a substation bus, the method comprising: measuring an amplitude and a phase angle of an electrical current being output by a transformer in the electrical substation to the substation bus electrically connected to the feeder line, utilizing a first sensor; measuring an amplitude and a phase angle of a voltage being output by the transformer in the electrical substation to the substation bus electrically connected to the feeder line, utilizing a second sensor; determining a reactance value based on the amplitude of the electrical current, the amplitude of the voltage, a phase angle between the electrical current and the voltage, and a predetermined constant, utilizing a processor; accessing a table having a plurality of position identifiers associated with positions on the feeder line, and a plurality of reactance component values corresponding to reactance components of Thevenin impedances at the positions on the feeder line relative to the substation bus, utilizing the processor; selecting a first reactance component value from the plurality of reactance component values in the table that substantially corresponds to the reactance value, utilizing the processor; selecting a first position identifier from the plurality of position identifiers that is associated with the first reactance component value, utilizing the processor, the first position identifier indicating a first estimated position of the single phase fault to ground in the feeder line; and displaying the first position identifier on a display device, utilizing the processor.