Propagation of partial discharge signals and the location of partial discharge occurrences

The location of the partial discharge source in transformer insulation was analysed by simulation studies. The partial discharge source was modelled such that it radiates the Ultra High Frequency (UHF) signal. It was observed that there exists a time difference of arrival of the UHF signal at the sensors based on its distance from the location of the partial discharge source. Also the magnitudes of the signal at the sensors also vary with respect to its distance from the location of the partial discharge source. The UHF signal gets attenuated in the presence of a barrier. It was also observed that the attenuation of the signal increases with the increase in the barrier thickness. The location of the partial discharge source was analysed based on the time difference of arrival calculated by first peak method and cumulative energy method. The first peak method was found to be more accurate compared to the cumulative energy method.