Distance Effect on Lightning Electromagnetic Pulse over Lossy Ground

Electromagnetic pulses produced by lightning return strokes travel both above and underground for long distances. Lightning electromagnetic pulses are caused significant effects and disturbances on the function of nearby systems such as power, communications, and etcetera. Electromagnetic fields are propagate into both above and underground for long distances. This study purposes to increase the comprehensive about the effect of distance on the lightning electromagnetic propagation over frequency-dependent soil. The modified transmission line with exponential decay (MTLE) model is used to model the lightning return stroke channel. The return stroke, and electromagnetic propagation models were modeled using RF-Module in the form of finite elements analysis via COMSOL software. The studied electromagnetic components are radial electric field, vertical electric field and azimuthal magnetic field with various distance from lightning channel. Furthermore, their behaviors with different soil water content up to 100% were as well studied. Peak values, wave shapes, and polarities of the above/using frequency domain solvers under ground electric and magnetic fields are influenced by distance from lightning channel. The aboveground fields are differently affected by the soil water content for various distances. In contrast, the behaviors of soil water content of underground fields are non-significantly affected by the distance from lightning channel.