State of the MV power cables insulation in dependence on the network operation conditions

Tests of several dozen sections of MV cables with extruded insulation, maintained in real conditions, confirmed that the process of degradation of polyethylene cable insulation depends on where the cable is placed in the MV power network. Measurements of thermal properties and resistance to partial discharges, and assessment of molecular molar mass of particular insulation layers were conducted, with the samples of insulation obtained from real cables.