Condition assessment of power cables in the ENEL distribution network, considerations after 2 years trial

Cable MV lines represent a very sensitive portion in the distribution network, because of the potential technical and economical impact of failures. In the last decade several diagnostic systems were developed aiming at assessing the cable line conditions mainly trough the use of a diagnostic indicator based on the PD (Partial Discharge) activity. Several reports are available in the technical literature about their performances and their ability to spot out potential defects; however the analysis is often based on a quite limited set of case studies. On the other hand, ENEL Distribuzione carried out a very extensive survey of its distribution cable network and the present paper reports and discusses some of the major results both in terms of analysis of the technical validity of the diagnostic systems used and of the economical benefit obtainable with this activity