Dielectric Characterization Study on Medium-Voltage Ethylene Propylene Rubber (EPR) and Tree-Retardant Cross-Linked Polyethylene (TR-XLPE) Cables under Varying Thermal Conditions

In this work, a systematic study of the dielectric spectra of full-scale medium-voltage (MV) ethylene propylene rubber- (EPR) and tree-retardant cross-linked polyethylene-(TR-XLPE) insulated cables is presented within the frequency range from 10
^-1
Hz to 10
⁶
Hz at various temperatures from 25 °C to 80 °C. The measured spectra were fitted using Havriliak-Negami (HN) model to find potential indicators of temperature variation. Results show that a complete modeling of MV cable section requires understanding of dielectric properties of insulator layers as well as distinct behavior of semi-conductive layers, particularly at frequencies above 10
⁶
Hz.