279 / 2018-09-25 14:29:07

Influence of Key Physical Properties of dc GIL Insulator on Surface Charge Accumulation

Surface charge accumulation; Relative dielectric constant; Temperature gradient; COMSOL simulation model; Charge density

Compared with overhead lines, gas-insulated metal enclosed transmission lines(GIL) have higher reliability, larger transmission capacity and better environmental protection performance, and can replace traditional overhead lines for power transmission in some areas with high requirements. However, dc GIL have not been developed on a large scale due to surface charge accumulation. COMSOL simulation is used to study the influence of some key physical properties of insulators on the surface charge accumulation. The results show that the higher the relative dielectric constant and temperature gradient are, the more insulator charge accumulation is. Therefore, in practical operation, the charge accumulation of insulator can be inhibited by reducing the relative dielectric constant and temperature gradient of insulator to improve its withstand voltage.