Pollution and ageing performance of DC line composite insulators: service experience vs. laboratory experience - (PPT)

摘要

Based on the recent discussions within CIGRE/IEC it can be estimated that about 20 millions of high-voltage line composite insulators are applied at present in HVAC overhead lines with an exponential market penetration trend. The first installations were made in 1967 in West Germany in industrially polluted areas and in The Netherlands in areas with coastal pollution profile. Thus, the longest service record in AC for line composite insulators is over 40 years. "Standard" advantages of composite insulators in comparison to traditional ceramic insulators made of glass or porcelain are: weight, pollution performance, resistance to vandalism. Line composite insulators have also been adopted for DC about 10 years later than for AC. However the volume of field/service experience in DC is much lower, which is mainly related to the fact that the number of DC lines are much smaller in the world than AC ones. At the same time, in DC advantages of composite insulators are utilized much better than in AC, because the main dimensioning factor in DC is pollution performance, where composite insulators have superior performance in comparison to ceramic insulators. At the same time optimally-dimensioned for pollution, DC composite insulators should be verified for ageing performance. Thus, this paper concentrates on analysis of pollution and ageing performance of DC composite insulators with emphasis to field/service experience, which is compared with laboratory experience.