Lightning return stroke electromagnetic field and energy at close distance by using 3D FDTD simulation

Abstract

In this paper, the lightning return stroke electromagnetic field at close distance is calculated by the way of transmission line (TL) model and full-wave three-dimensional electromagnetic field simulation software XFDTD, which is based on finite-difference time-domain (FDTD) method. The evolution of distributions of electric field and magnetic field are summarized in the study. Furthermore, the total electromagnetic field and major components are analyzed to clarify the electromagnetic hazard from lightning electromagnetic pulse (LEMP). Then the temporal and spatial distribution characteristic of Poynting vector of the electromagnetic environment is shown to expound the energy distribution of LEMP at close distance. The results based on the analyses of field strength and Poynting vector show that the distribution of electric field, magnetic field and Poynting vector at close distance is akin to multilayered cylinder, and LEMP in the region characterized by large amplitude, transient behavior and high electromagnetic energy is a potential threat to adjacent electronic equipments. Moreover, engineering basis concerning LEMP protection and electromagnetic compatibility (EMC) design in the region closed to the return stroke point can be provided by the synthetical analysis of LEMP.