Lightning Performance Analysis of Multi-Circuit Transmission Line Based on EMTP-Embedded Volt-Time Characteristic Model of Insulators

摘要

The calculating model commonly used for predicting the lightning performance of transmission line did not take the lightning impulse flashover volt-time characteristics of insulator into account. It can not give reasonable result of multi-circuit simultaneous trip-out rate for multi-circuit transmission lines. Different types of flashover criterion of insulators are discussed. The equivalent air gap length of insulator is acquired to be used in the leader development model. An embedded model, which adopts leader development method to simulate the progress of insulator flashover step by step in EMTDC has been constructed. By means of above model, the lightning protection performance of a 500-kV four-circuit transmission line is analyzed in detail.