3D Electric Calculation for a Station Class ZnO Surge Arrester for 1100kV Substation Using the Hybrid Finite Element-Analytical Approach

In this paper, a hybrid finite element-analytical approach for 3D potential calculation for a station class ZnO surge arresters for 1100 kV substation is presented. In this hybrid approach a circular cylinder surface fictitious coupling boundary is employed to divide the infinite region into two an interior region and an exterior region. The field in the interior region involving a ZnO surge arrester of which the medium and configuration are complicated is discretized using finite element method, and meanwhile the field in the exterior region involving a homogeneous medium the eigenfunction expansion is represented. Many factors influencing on the visitors potential distribution are discussed. At lasts an appropriate grading ring configuration is suggested