Numerical Research of High-Voltage Conductors: Electric Field Characteristics in Ice-Covered Spaces

The icing of overhead high-voltage transmission lines not only caused accidents such as line dance down pole and flashover, but also lead to abnormal field strength on the line surface and distortion of electric field distribution, which threatens the normal operation of the power system. On 500KV transmission lines, a numerical model of the ice cover conductor considering the dielectric properties of the ice layer was established, considering the influence of the spacer strip. The local spatial electric field distribution inside and on the surface of the ice sheet under different ice cover severity was studied. The numerical calculation results showed that the electric field variation inside the ice sheet was amplified, and the electric field distortion rate in the ice cover case was larger than that in the ice-free case at the spacer strip, and both are larger than 150%. In the crescent-shaped transit ice, the aberration rate at the spacer bar inside the crescent-shaped ice decreases with the extension of the crescent-shaped ice, and the electric field aberration rate at the surface of the icicle in the overhanging transit ice was about 20%. The study showed that ice with different characteristics had a significant effect on the electric field around transmission lines, and the study of high-voltage transmission lines over ice could introduce changes in the electric field.