| Abstract [eng] |
The literary sources analyzed in the review part relate to the use of high-voltage cables in electricity transmission networks and the causes of cable failure. The first part of the review analyses the growing demand for cables, laying trends, advantages and disadvantages compared to overhead lines. In the second part of the review, the causes of failures of high-voltage cables are analyzed – describing external and internal cable failures, their causes and the frequency of failures of cables and their components. The aim of the research is to analyze the influence of impulses caused by lightning discharge on the insulation of 110 kV underground cables. Literary sources and EMTP software were used to carry out the research, which simulates transition processes and in which a 110 kV power grid model is developed. With the help of the developed model, the pulse caused by the lightning discharge on cable lines was modeled: when lightning hits the overhead lightning protection cable and when lightning hits the overhead phase wire. The modelled cable line insert model is designed to be 100 m, 300 m and 600 m long. The analyzed results of the modelling transitions showed induced voltages on other cables, the influence of surge arresters, the grounding of cable screens, the resistance of the grounding and the shortest length of the cable line, which, due to the pulses caused by lightning discharge, would not damage the cable insulation and which would ensure long-term and reliable operation of the cables for the newly installed 110 kV cable lines. |
