40 / 2021-05-25 19:01:00

Analysis and Suggestions on String Breakage Failure of Composite Insulator of Overhead Transmission Line in Central China

The disconnection of composite insulators in Hunan Power Grid in the past 10 years is analyzed in the paper. It is found that the composite insulator of 500kV line has a higher probability of disconnection. There are two types of the disconnections: 6 times of body damage and 1 time of unreasonable design. 2 times of body damage are mandrel brittle fracture and 4 times are mandrel crisp fracture. 10 samples were selected to carry out mechanical and electrical tests in the laboratory. The failure of the same batch of samples was not detected in mechanical failure load, leakage resistance, mandrel acid resistance test and cutting inspection. The optimization suggestion of the test items of composite insulator spot check is put forward.