Variation of Surface roughness and Corona Characteristics of Transmission Lines in Shandong Power Grid

Aging conductors used in high voltage transmission lines in Shandong province of China were carefully selected and sampled. The Effect of the pollution area and service year on surface conditions and corona discharge was analyzed. Experiment results show that general environment had a significant effect on the surface conditions. The surface roughness increased as the pollution grade increased, and the same was with service years. At the same pollution grade, corona discharge of the longer operated lines is more serious, and the law was the same with the service year.