A new approach for evaluating the condition of cable systems and estimation of remaining life time of MV underground power cables

Abstract

This study focuses on one of the key questions of underground distribution network operators. How can the remaining life time of underground power cables be estimated? The answer to this question is explained by a new approach of KEPCO Korea. When combining VLF Tan Delta (TD) and Partial Discharge (PD) diagnostic it is possible to identify and localize weak individual spots along a cable. After weak spots are cleared, the general aging condition of the cable can be judged and the Remaining Life Time can be estimated. The implementation of this approach in the KEPCO Distribution Networks is illustrated in a practical case study. A new tool for asset managers is available and it is expected that it will help to further develop the preventive maintenance approach by power utilities all around the world.