Analysis of 3-D partial discharge patterns in XLPE power cable based on fractal theory

Fractals have been very successfully used to provide a description and to model mathematically many of the naturally occurring complex phenomena and shapes. Partial discharge (PD) occurring in XLPE-power cables is a cryptic phenomenon, with detectable features differing in a thousand ways. In this paper, the authors have investigated and presented preliminary results on the use of fractal features for recognition of 3-D PD patterns. This work is based on the assumption that the random 3-D PD pattern surface qualifies as a fractal surface and it was found that two fractal features, fractal. dimension and self-similar characteristic, possess reasonably good pattern recognition capabilities. According to fractal surface shapes of 3-D partial discharge patterns, correlative function and fractal dimension of the fractal surface are established in this paper. Recognition of PD signal is put forwards based on fractal features of 3-D PD patterns.