Analysis of lightning transient in 2 × 25 kV AC autotransformer traction system

摘要

Lightning is one of the most important issues of power outage in electric networks. Surveying overvoltage caused from lightning event in electric networks and proposing approaches to reduce the overvoltage are significant issues. Lightning struck to the traction networks caused some undesirable effects on traction substation equipment, overhead lines and trains. To avoid causing the above problems, lightning arresters are installed in critical points of the network. In this paper, in order to better assess lightning impacts on the traction systems, firstly, all parts of the traction system are modelled in EMTP software. Then, network analysis and induction voltages in various sections are determined. Consequently, according to the maximum overvoltage, critical points are determined based on the simulation results. Induction voltages are measured in different parts of the system such as overhead lines, autotransformers, MAST and train. The achieved curves showed the effect of lightning arrester in reducing overvoltage obviously.