Luminescence in crosslinked polyethylene of high voltage cables

Abstract

Luminescence can occur in crosslinked polyethylene (XLPE) of underground high voltage cables. Above room temperature XLPE emits thermoluminescence even without voltage application and the intensity of this light depends on the concentration of the crosslinking by-products present in the polymer. Above a certain threshold voltage XLPE, at or above room temperature, emits electroluminescence and the inception voltage of electroluminescence is the threshold voltage at which the polymer starts to degrade. While the spectra of electroluminescence are in the visible and ultraviolet ranges that of thermoluminescence are only in the visible range.