Dynamic behavior of water droplet for evaluating outdoor insulator

With the wide application of outdoor insulators made from silicone rubber, the electrical accidents induced by the ageing of silicone rubber insulators cause the increasing concern of researchers. Based on a dynamic drop test, this paper focuses on the discharge characteristics generated by the dynamic behavior of water droplet to evaluate the hydrophobicity for different service time of silicone rubber insulator. The discharge phenomena were captured by using a high-speed camera and the light intensity of discharges was measured by a photo multiplier tube. Meanwhile, the electric field distribution at just dropping of the droplet was calculated to reveal the relationship between the discharges and the hydrophobicity. It is found that with the decrease of hydrophobicity, both the number and duration of discharges show the increasing tendency. The increase of discharge intensity and related light intensity reveal the decrease of hydrophobicity.