Parametric analysis of overvoltages caused by back-flashover in “Siah-bishe” 400kV GIS substation

This paper presents the way of implementation of transient modeling concepts which are fully analyzed in referred standards, for the purpose of evaluating the lightning performance of studied system caused by back-flashover. In this regard, the impact of several parameters on lightning behavior of the system has been studied. The focus of this paper is on the lightning study of “Siah-bishe” 400kV gas insulated substation (GIS) and practical application of the study to the insulation design of this substation as a substation with a distinctive arrangement of equipment. This practical application has been rarely done before. The study was carried out by modeling all pieces of equipment in EMTP-RV and careful consideration of different modeling guidelines and instructions described in available standards.