Study on Different Dimensions of C-type Corona Rings in 400 kV Insulator Strings Based on FEM Analysis of Electric Field Distribution

This paper presents analysis of electric field distribution and optimization of C-type corona rings for 400 kV V-insulator strings composed of ceramic insulator units which are the most common configuration of overhead transmission lines. These strings are equipped with corona rings to enhance the insulation performance regarding to the effect of these rings on the insulation function and potential and electric field distribution. 3D field simulations are performed for the C-type of corona rings with different dimensions by software based on FEM analysis.