Life Management of 550kV SF6 circuit breakers

In order to evaluate the actual condition of high voltage SF6 circuit breakers, a reliable measurement of their ageing and failure characteristics with suitable sensors and condition monitoring is necessary. In this paper, reliability models are developed for individual characteristic parameter such as SF6 leakage, N2 leakage, or oil leakage and control- and protection problem, etc. The physics - statistics based life model is developed and improved on the basis of the data collection which describes the electrical, thermal, and mechanical ageing behaviour of high voltage SF6 circuit breakers with individual parameter, depending on the statistical surveys on failure.