Potential and electric field distributions on HV insulators string used in the 400 kV novel transmission line in Algeria

Recently, the Algerian Society of electricity and gas (SONELGAZ), introduces a higher voltage level into its electrical system to meet the increasing demand for the highest quality of service and security of supply. This paper deals with the distributions of the potential and the electric field inside and around I, II and V cap and pin insulators string in 400kV AC transmission lines. It is well known that such distributions are affected by many factors such as the influence of tower, voltage magnitude, corona ring, contamination and environmental conditions. In order to approach the ideal conditions where the voltage would be linearly distributed on the whole of insulators string, corona rings are added. The computer simulations are carried out by using the COMSOL Multiphysics 3.5 software. This program uses the finite element method to solve the partial differential equations that describe the field. The simulations are conducted for different corona ring parameters such as mounting height and diameter.