Localization of partial discharge sources along HV and MV cable routes

In this paper, partial discharge (PD) source localization on HV polymeric cable systems is dealt with. The capability to detect defects within insulating systems helps avoid premature and unexpected failures and constitutes the prerequisite for any effective risk analysis. Therefore, partial discharge assessment, mainly aimed at detecting localized degradations, can improve reliability and availability of electrical apparatus, supporting effective practices of condition based maintenance. However, information about the exact location of the defect generating PD, which is a fundamental item for an optimized and cost effective maintenance action, cannot be derived from the usual results provided by partial discharge measurements. Three different methods for PD source location based on ultra wide bandwidth detection approach are presented in this paper. Experiences of on site application of these three methods are reported and discussed. Moreover an analysis of the effectiveness of the different methods in relation to the type of cable system under test is provided from both economical and technical points of view