Abstract
This paper presents results that demonstrate the
effects of fulgurites on the earthing system of a power system.
The importance of grounding in power systems cannot be over
emphasized. Although studies of fulgurites have been done in
the past, no research work has reported on the impact of
fulgurites on electrical grounding. The backfill materials used
to enhance an earthing system play a pivotal role in
controlling ground impedance of the soil by lowering the
impedance of the earth. The impedance of the grounding is the
sum of the static and dynamic impedance. The results of this
work show that the static impedance of the backfill material
increased in the event of fulgurite formation. Regarding the
soil sample studied from a Swaziland 11 kV feeder, this
occurred for lightning impulse currents equal to or greater than
30 kA. Swaziland is a country that experiences frequent power
failures due to lightning, especially during the rainy season. It
is thus essential to have a sound grounding system that is able
to withstand all types of fault conditions and hence, the need
for this study. The long-term aim of this research is to
characterize a backfill material that will address the
performance requirements of the network earthing system.