Estimation of shielding failure number of different configurations of double-circuit transmission lines using leader progression analysis model

摘要

The protection of overhead transmission lines from lightning strokes is one of the most important tasks of safeguarding electric power systems. In order to do this job effectively, the lightning performance of the transmission lines has to be evaluated accurately. This paper presents the development of a method for estimating the shielding failure number of power transmission lines in different configurations by using the charge-simulation method. The effects of towers, sags of conductors, and a perfectly conducting ground are represented in a 3-D computation. In addition, the stepwise descending nature of a downward negative leader-streamer systems is taken into account by using an appropriate progression model. Upward leader inception and propagation is also modeled utilizing critical equivalent streamer-length criterion. The method is applied to compute the shielding failure of power transmission line for different configurations.