Lightning Induced Voltages on Overhead Power Distribution Lines: Influence of rate of rise of Lightning current

Abstract

Computation of induced voltage on an overhead line due to an indirect lightning stroke involves calculation of electric field due to the lightning stroke as well as its coupling with the overhead line. The ground conductivity influences both the electric field as well as the coupling mechanism and hence the magnitude and waveshape of the induced voltage. The induced voltages are calculated for 33kV, 3φ over head power distribution line for lightning return stroke currents of 3 different rate of rise with constant peak value. It is observed that there is no significant increase in the magnitude of induced voltages as the maximum rate of rise of lightning current is increased. However if the maximum rate of rise of lightning current is increased by 10 times, the maximum rate of rise of induced voltage at line termination is increased nearly by 3.5 times whereas at the line mid point it is increased by 5 times for the lightning striking location studied. © 2006 EMC Europe 2006 Barcelona, International Symposium on Electromagnetic Compatibility All rights reserved.