Surge threats appear in railway devices feeding lines

Trolley wires nets and railway traffic controlling devices (rtc), enclose in their range considerable areas of the country, are subject to the influence of lightning discharges. This threat can be a result of a thunder direct hit into the trolley wires or the non-traction line (NTL). It can be also a result induced voltages by nearby discharges to earth. The resulted damages of electric and electronic devices or of their components cause losses eg. in the form of delays of trains and their results. To prevent suchlike disturbances is a very complicated problem and needs to interosculate many issues, and one of the methods is the mathematical analysis. In the report were represented the results of modelling of induced surges called out by lightning discharges for a real case of damage of the railway traffic controlling devices as a result of atmospherical origin surges. The analysis was passed in the Lightning -Induced OverVoltage (LIOV) pack implemented on EMTP-RV programme. The compared surges were matched to the lightning currents component given in the standard PN-EN 62305-1. The influence of the analysed system parameters of the line nearby the lightning channel on shapes and top - values of the induced voltages was estimated.