Multi-stress electrical and thermal ageing of HV extruded polymeric cables: Mechanisms and methods

This paper examines recent developments in the study of the ageing of polymeric materials subject to long-term electrical and thermal ageing. These demonstrate the need to understand and model heterogeneous ageing, localised degradation processes and progressive damage accumulation that can lead to defect propagation and catastrophic failure. This is discussed in the context of a current European Commission funded project called ARTEMIS (Ageing and Reliability TEsting and Monitoring of power cables - diagnosis for Insulation Systems) which aims to provide the cable manufacturers with a practical diagnostic method for assessing the condition and remaining lifetime of extruded polymeric cable. The paper reviews a number of the experimental results linked to the validation of this model using specimens taken from model cables with extruded and crosslinked polyethylene (XLPE) insulation.