Calculation and measurement of potential and electric field distribution along 1000 kV AC transmission line composite insulator

Potential and electric field distribution along 1000 kV AC transmission line composite insulator are analyzed in this paper. A sub-model approach based on finite element method (FEM) is applied in calculating the potential and electric field distribution along the insulator under clean and dry conditions. Using this approach, three dimensional (3D) electrostatic models taking into account the grading rings, conductors, cross arm are set up and investigated. To make a comparison, the simulated measurements considering the grading rings, conductors and cross arm are also carried out at Wuhan High Voltage Research Institute (WHVRI) UHV outdoor test yard. A relative good agreement between the calculated and measured results of some sheds is obtained. The results of comparison and discussion can be a reference for the UHV AC transmission line external insulation configurations design in China.