Online decision rule-based method for localization of PD sources in multi sheath grounded single core cables

In this paper a decision rule-based method is presented for localizing partial discharge (PD) sources in single core cables with multi sheath-ground connections and/or discriminating different combinations of single or double defected cable sections. Through investigations on the characteristics of various PD features, the energy of wavelet transformed PD signal is considered as most appropriate index, whereby the energy distribution pattern (EDP) from all sheath-ground connections is constructed. The proposed rules formulate the EDPs of different combinations of defected cable sections under various PD source characteristics and PD source locations on defected cable section. The results, found through simulations, show the highest possible accuracy in PD source localization for different combinations of single or double defected cable sections. Moreover, the proposed method is extended to include the cases that the boundary of cable network under consideration approaches to a line-cable junction where also acceptable results are obtained.