Some Experiments on Thermal Aging of XLPE Underground Cables

Thermal stress effects on the insulation material of high voltage underground cables plays a significant role in assessing the working life. Experimental based thermal aging tests are performed on a widely used high voltage cable insulation in this study. The cable in its entirety is aged at three different temperatures for a duration of 12 months. The subsequent changes in the electrical and morphological properties are studied. Dielectric breakdown test along with dielectric constant and dielectric loss tan $(\delta)$ analysis is done to determine the electrical property changes. FTIR and XRD are done to understand the morphological changes. The results obtained provide the temperature at which the material degradation is least and performance is not hindered.