On-site diagnosis of transmission power cables

Condition assessment of HV assets is one of the issues of asset management introduction in power utility business. In particular, due to there importance in the transmission network is the knowledge about the starting conditions during after-laying as well as the actual condition of HV power cable sections during operation after several years of service of great importance. In an international co-operation, based on utility experiences and laboratory investigations as obtained for PD diagnosis of distribution power cables using damped AC voltages a complete new method of PD detection and localization for transmission power cables up to 250 kV has been developed in 2003 and in use for already one year. In this contribution based on field experiences as obtained in the Netherlands for cable systems up to 150 kV the aspects of sensitive PD detection and location are presented and discussed