Calculation of Electric-field Distribution and Research on Characteristics of Shielding Ring along the Long-rod Post Porcelain Insulators Used in 1000kv System

In this paper, the finite element method is used to calculate the three-dimensional electric-field distribution of long-rod post porcelain insulators used in 1000 kV system. The electric-field distribution is simulated in the condition of varied position, varied major radius and varied section dimension of the shielding ring. The effect of these factors to the external insulation characteristics of post porcelain insulators is analyzed. The electric-field distribution at the line side and the grounding flange can be effectively improved by proper distribution of shielding ring and the optimization of the shielding ring structure. This provide calculation gist to improve the characteristics of shielding ring used in 1000 kV long-rod post porcelain insulators and the reliability of safe operation in 1000 kV system