This paper shows the results of the use of PD-OL over several years. PD-OL is an on-line partial discharge (PD) based monitoring system for mv power cable systems up to 8 km, available since 2007. It can locate all PD sources. PD monitoring can be done over any desired period, hours to years, its results being visible via internet with an hourly update. This paper will introduce the measuring system shortly and will focus mainly on summarizing its effectiveness. This effectiveness is derived from results obtained by monitoring 136 circuit km of mv power cable with about hundred measuring systems since 2007. It will be shown that the proven effectiveness in preventing failures is above 80 %, depending on the cable type (PILC or XLPE). One early finding for instance is that certain defects in joints for extruded mv cable develop PD's only a couple of days before the breakdown, based on which the network owner decided for immediate corrective actions in such cases, preventing in this way dozens of new failures, all proven to be related to real problem joints based on visual inspections after replacement.
|Title of host publication||Proceedings of the International Conference on Condition Monitoring and Diagnosis (CMD), 6-10 September 2010, Tokyo, Japan|
|Place of Publication||Z.pl.|
|Publication status||Published - 2010|