Thermal Degradation of Insulating Systems Based on Dielectric Currents

This work presents the dielectric currents of insulating systems with its several components. It is a study about the physical nature of dielectric insulating materials with its effects of electric polarization when subjected to electric field influence. The main objective of this study is to show the dielectric insulating materials degradation speed dependency on temperature. A method is proposed to quantify the insulating system aging speed based on dielectric current measurements. It is presented the physical nature that causes the aging of the dielectric materials molecular structure based on the variation of the dielectric currents as a function of temperature. It is showed that the insulating system degradation speed becomes higher from a characteristic temperature value on and, that this value can be or not coincident with the thermal class temperature. The electric circuit arrangement used to measure the dielectric currents is presented. Finally, experimental results obtained with insulating systems of thermal classes B, F and H are presented, to demonstrate the application of the proposed method with the respective conclusions and comments.