Estimation of deterioration and failure probability of water tree degraded XLPE MV underground cables

This paper presents an approach for estimation of deterioration and failure probability of water tree degraded crosslinked polyethylene (XLPE) medium-voltage (MV) underground cables. The approach is based on a general analysis framework that can be used for various components in the power grid. A case study is presented where the general framework is applied to a specific power cable. A reliability model with five condition states is used to model deterioration and to calculate the failure probability. The paper shows how existing databases and knowledge from experts combined with a structured approach can be applied in a reliability analysis.