Failure prediction system of water treeing using 3D VLF tandelta of MV cable

In this paper, Underground distribution power cable of 20,000 lines was diagnosed using VLF(Very Low Frequency) tanô method. The accumulated big data is analyzed statistically with the Weibull distribution, and the 3D model is implemented through the matrix of statistical factors of TD (average of 8 point tanô), DEV(deviation), STDEV (standard deviation) and SKIRT(deviation slope of 8 point tanô). Also, we propose a new concept of Aging Index R. The deterioration state of the power cable and the remaining lifetime are estimated according to the position of the index R. As a result, it is possible to determine the economical and reasonable replacement cycle of the power cable. Thereby maximizing the power efficiency of power operation and cost reduction of maintenance.