Breakage Mechanism Study of Overhead Ground Wire Under Lighting Stroke Based On Finite Element Analysis

摘要

Breakage of overhead transmission lines and distribution lines will lead to severe power outage problems, and clarifying the breakage mechanism of the overhead lines is of great importance and value for the reliability and stability of the power system. Taking overhead ground wire for example, this paper presents its breakage mechanism study under lighting stoke based on finite element analysis. A multi-physics analysis model is built first, which includes the model of contact points. The current density distribution and the temperature rise under the impact of short circuit current are analysed, and contact resistance effect is proved the primary cause for the breakage. Then some major factors that influence the contact resistance which in turn influence the temperature rise are discussed. Based on the discussions, some valuable suggestions are given for the protection of overhead lines.