Partial discharge characteristics of electrical trees in XLPE power cables

Abstract

This paper studies the initiation process and the PD characteristics of electrical trees, and proposes a new method to recognize the growth state of electrical trees. The experiment result show that the electrical trees PD energy mainly concentrated in the −40°∼90° and 120°∼250° of 5MHz∼7.5MHz, −20°∼90° and 150∼250° of 7.5MHz∼10MHz. With the dense increase of the electrical trees, the more PD energy will be found in the frequency 7.5MHz∼10MHz. At the first development stage of electrical trees, the PD energy mainly located at the frequency 5MHz∼7.5MHz, when electrical trees develop to the next stage, the more PD energy will be found at the frequency 7.5MHz∼10MHz.