Phase-resolved measurement and modelling of electroluminescence phenomenon in polyethylene subjected to high electrical stress

Electroluminescence (EL) has been widely used as a probe to study early electrical ageing in high voltage cable insulation systems since it can be associated with the energy dissipation of mobile and trapped charges in the molecules of the dielectric medium. In addition to that, the study of charge injection and recombination mechanisms at the metal-polymer interface can also be deduced via EL observations. This paper presents a series of measurements undertaken at Southampton to observe the occurrence of EL with respect to the alternating electrical stress in order to gain a better understanding on the processes responsible for light emission. Attempts have also been made to simulate this phenomenon using a simple approach relating the charge injection and recombination mechanisms within a polymeric material.