Localization of a Partial Discharge Source Using Maximum Likelihood Estimation

Analyzing the electromagnetic waves generated by partial discharges is effective to assess insulation degeneration. In this paper, we describe a locating method for a partial discharge source based on maximum likelihood estimation. This method uses the root mean square and the direction of arrival of partial discharge signals which are calculated from measurement data obtained using sensors. This information is integrated using the maximum likelihood method. In this case, only the signals received in a good reception condition are used because the signals affected by multipath effects can decrease the estimation accuracy. This paper considers the case that apparatuses interrupt the direct paths from a partial discharge source to sensors. The capability of the proposed method was confirmed by simulations using the finite difference time domain method. The results include the comparison of performance for the number of sensors and show that this method has enough resolution to detect partial discharge sources. (C) 2010 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.