Mechanism of space charge formation in cross linked polyethylene (XLPE) under temperature gradient

A bipolar charge transport model is used to simulate the formation of space charge in XLPE plaques placed under a temperature gradient. The model is used to assess the relative importance of charge migration and blocked extraction for three possible effects of the temperature gradient. The simulations were carried out for samples with different thicknesses and the results verified by comparison with experiment. In this way it has been shown that not only does the temperature gradient influence space charge accumulation through its introduction of a conductivity gradient, but also through differences in the injecting and extracting processes at electrodes of different temperature.