Study on influence of temperature gradient of XLPE insulation on electrical tree

Cross-linked polyethylene（XLPE） power cable is an important part of the power supply network in the city, and the failure caused by the insulation degradation is an important factor that threatens the long-term stable operation of cables. Under operating conditions, there is a radial temperature gradient within the cable insulation,which may affect the growth process of electrical tree. For XLPE, it is of great significance to study the influence mechanism of temperature gradient on the growth of electrical trees, and to improve the reliability of cable operation. The XLPE sample and AC voltage are selected to study the growth trend of electric trees under multiple temperature gradients. The results show that the presence of temperature gradients will promote the growth of electrical trees, and the morphology of trees will change with the presence of temperature gradients. The difference in electrical conductivity and the change in charge energy caused by temperature are the main reasons for the difference in morphology and growth rate of electrical trees.