Lightning radiated electric fields and their contribution to induced voltages

During the return stroke, the radiated electric field from a lightning channel contains vertical and horizontal components of the electric fields, which are both responsible for producing transients in power lines, telecommunication lines, and electronic circuitry of communication and control systems. This paper analyses the characteristics of the vertical and horizontal components of the electric field depending on different parametric conditions of the return stroke. Lightning induced voltages on an overhead telecommunication line are also calculated for different elemental fields. The numerical results show that horizontal electric field (HEF) produces high ringing of fields at distances far from the strike point, and plays an important role in producing induced voltages in the vicinity of the lightning channel. The radiation and the induction components of fields are found to be responsible for the change in polarity of induced voltages.