Development of partial discharge model, simulation and measurement

In cases, when there are electrically weak areas in solid dielectric materials (most often gaseous or liquid inclusions), partial discharges (PD) can be measured when voltage is applied. Partial discharges cause degradation in insulated materials. The investigation of insulated material behavior under electrical stress and the data obtained from PD measurements provide the possibility to predict dielectric breakdown. PD measurements are affected by electrode arrangements and by measuring circuits (MC). It is very important to investigate the relation between experimental PD data, electrode arrangement and the elements of measuring circuits by applying computer models. The present paper considers PD behavior of polyethylene voids. Various models have been built using special software tools for analogue design and simulation. The results obtained have been analyzed and discussed in order to assess the influence of various types of measurement circuits. The data obtained from the model have been compared with the experimental results from polyethylene samples with artificially introduced cylindrical voids subjected to PD. The electrode configuration used is plane-plane, and electrodes are parallel to the cylinder ends of the void. The parameters of the models correspond to the parameters of the experimental set-up.