Characteristic Analysis of Electrical Tree Initiation using PD Distribution and Statistical Parameters in Variable Defected Models in Solid Insulator

Electrical tree in solid insulator is very important thing because the tree is affected to insulation failure. The life of the tree is covered from initiation, through propagation, to long-term changes in shape and length. In this paper, we discuss the inter-relationship characteristics of tree initiation, phase resolved PD and statistical distribution of the PD. To acquire PD data from electrical tree discharge, three types of electrical tree models are made, that is, needle to plane electrode in insulator, needle with void to plane electrode and needle with metal tip to plane electrode in insulator. PD data are acquired by computerized PD detector, and then statistical parameters of PD are calculated to analyze tree initiation characteristics