Study of space charge behavior of insulations for high temperature applications

The role of space charge under DC electric field on aging of cable insulation has been proven. In providing the space charge electric field and temperature are two effective factors. This paper investigates the influence of temperature on making space charge in a special group of materials used in high temperature (HT) application. These insulations usually are under normal electric field, but the effect of temperature on their space charge can be vital. For this, a list of commercial HT materials were selected and their space charge results under normal DC electric field and three different thermal conditions from room temperature (RT) to 200°C were compared. To analyze the results some electrical indexes like amplitude of space charge and maximum electric field enhancement (MEFEP) are utilized. Based on the results, Fluorinated ethylene propylene (FEP) has the lowest space charge and MEFE due to the HT condition among the studied materials.