Simulation Performance of Lightning Discharges around Medium Voltage Underground Cables

This paper studies the performance of an MV underground cable due to a nearby lightning discharge. The simulation is made with Finite Element Method (FEM). The effects of lightning stroke location, resistivity of the soil and underground cable configurations are considered. The results of the numerical computation show how electric field intensity and potential distribution vary with the factors mentioned above. Estimations of the failure rate of the underground cable are made based on the real lightning statistics in Finland, considering homogeneous and inhomogeneous soils. It is expected that the results will provide a good understanding of the need for lightning protection on MV underground cables.