Correlation between PDIV and life distribution under different testing waveforms

The implementation of underground distribution lines has grown significantly over the last decades due to the rapid increase of electric energy demands. But, the lifetime distribution of lines is strongly affected by the single or multiple stresses that could develop in the insulation system of the power cables. In this paper, the influence of applied voltage waveform on partial discharge activity and lifetime distribution of insulation material for power cables was investigated. In this sense, the Inverse Power Law-Weibull model was applied in order to develop a life model of the PD induced degradation processes under different voltage waveforms occurring in micro-cavities from the power cables insulation system. For the insulation design it is of great importance to assess the insulation threshold by using the voltage tests. As result, the step-up test method was used.