Partial discharge position locating method and partial discharge position locating apparatus

摘要

PROBLEM TO BE SOLVED: To improve accuracy of a partial discharge position locating operation in a case a position of a partial discharge source of a stationary winding apparatus is inside the winding.;SOLUTION: When at least one AE sensor is mounted on a tank wall of an oil-immersed transformer and also the position of the partial discharge source is located based on an AE signal output from the AE sensor by using a partial discharge current flowing through a neutral grounding line as a trigger, a decision is executed whether the discharge source is positioned inside the winding or on outer circumferential surface part of the winding by performing at least one decision among a first decision performed by whether a rise time α of a direct arrival wave of the AE signal is larger than a set value α* or not, and a second decision performed by whether a first wave of the direct arrival wave of the AE signal is a low frequency component or not, and a third decision same as the second decision based on such a waveform that the AE signal is subject to wavelet transformation. Based on these decision, at least three AE sensors are mounted and the position of the discharge source is located by obtaining a propagation distance from the discharge source to each AE sensor by changing a propagation speed of the discharge sound according to different propagation medium, when the discharge source exists inside the winding, based on an arrival time of the direct arrival wave of the AE signal to be output from each AE sensor and a delay of the arrival time of the high frequency component.;COPYRIGHT: (C)2013,JPO&INPIT