Design and experimental study of electron beam treatment for composite insulator sheds

Abstract

Composite insulators, widely used in high-voltage transmission lines, feature silicone rubber sheds that age in complex natural environments. Applying electron beam irradiation to the silicone rubber can enhance their ageing resistance and hydrophobic properties. To advance the study of sheet silicone rubber to the entire insulator, this study proposes a method utilising a 5 MeV Dynamitron accelerator for treating a irregularly structured insulator. The insulator is irradiated in a state of tilted placement and rotation about its axis to achieve a uniform and consistent dose across the sheds. The irradiation process of the insulator with electron beams is simulated using Geant4, considering both instantaneous and cumulative states separately. The deflected particles from scattering and reflection of high-energy electrons interacting with insulator components have a significant impact on the dose distribution in each shed. Moreover, an optimal tilt of 20° ensures similar irradiation doses and high uniformity across all sheds. An experimental platform is developed for rotational irradiation of the insulator to ensure stable operation. Preliminary experimental results confirm that the doses across all sheds are uniform and consistent.