Online detecting insulator corona for diagnosing faulty insulators on transmission line

This paper describes some methods of differentiating insulator corona pulses from the current pulse signals on the grounded line of the tower, which could be used to identify faulty insulators on transmission lines. The pattern of noise and the insulator corona have been analyzed. A high frequency sensor with a filter is used to eliminate periodic noise, such as leakage current, harmonics and carriers. A pattern identification method of distinguishing the insulator corona pulse from the current pulse has been put forward, which is based on the pulse statistical characteristics. The field experimental results show that these methods are effective and useful.