The characterization of a LDPE affected by different levels of water tree degradation using absorption current measurements

In this work, in order to characterize the conduction process in polymer dielectrics, we focus our interest on the absorption current through LDPE. We have experimentally considered the influence of the degree of degradation or degraded width percentage and polarization voltage on the measurements of absorption current and capacitance. From the point of view of accelerated ageing, the typical electro-chemical degradation process of service power cables known as "water treeing" was simulated in the laboratory. Then we measured absorption currents for specimens with a different degree of treed degradation and finally, a correlation between the degree of ageing and the fitting parameters of current experimental data to the Curie-von Schweidler law was proposed.