Abstract
Insulators are one of the important components of overhead transmission lines. Because of their excellent characteristics, insulators have obvious advantages in the selection of external insulation in UHV AC transmission projects. The potential distribution of insulator string is not even due to the shape characteristics of insulator string, the structure of metal tool, the low conductivity of silicon rubber material and the stray capacitance between insulator string and wire, iron tower and metal tool. When the surface field intensity of insulators and fittings exceeds the initial field intensity, corona discharge will occur, which will affect the electromagnetic environment and the operation characteristics of insulating materials. Therefore, it is of great significance to determine the potential distribution of insulator strings of UHV transmission lines for detecting low and zero value insulators, implementing voltage equalization measures effectively, and ensuring the safe and stable operation of transmission lines. Based on Ansys software of 500kv transmission line insulator string, this paper establishes a three-dimensional model, the method of using finite element numerical simulation respectively with no equalizing ring and equalizing ring in both cases the umbrella skirt on simulation, the distribution of electric field along the roots, and further studies the equalizing ring the effect of different parameters on the electric field distribution. Finally, an optimal solution is established.