Aging diagnosis of silicone rubber composite insulator based on conduction current test

This paper presents a new criterion on aging diagnosis of silicone rubber composite insulator. Taking being operated composite insulators as the object, the electrical degradation threshold was obtained by the conduction current test, then the hydrophobic of samples was obtained by static contact angle measurement and the surface micro of samples was analyzed by surface electron microstructure (SEM). Preliminary tests indicates that the electrical degradation threshold of samples changing from 5 to 10 kV/mm with different aging degree, the more severe the degree of aging of the sample, the deeper its trap level, the lower the electrical degradation threshold, the greater the conduction current value. Research shows that electrical degradation threshold obtained by conduction current test of silicone rubber composite insulators can basically reflect material´s aging degree, electrical degradation threshold may become the new criterion for diagnosing aging condition of silicone rubber composite insulators.