Calculation of the lightning electromagnetic field for vertically stratified ground using the novel scheme FDTD

Lightning electromagnetic pulse is excitated and may cause instantaneous high voltage or current in electronic equipments through the electromagnetic coupling, which will lead to malfunction or even complete destruction. Research on the lightning process and fast and precise calculation of the lightning electromagnetic field is of great significance. A two dimensional cylindrical coordinate novel FDTD (NFDTD) algorithm with novel scheme is proposed in this paper in order to obtain the results with more precision than the traditional FDTD (TFDTD) for vertically stratified ground when the vertical interface is in the vicinity of the lightning channels. The numerical result shows that for vertically stratified ground when the vertical interface is not far away from the lightning channels, the NFDTD has higher precision than the TFDTD within the range of 50m from the lightning channels, and the results using the NFDTD and the TFDTD tend to come together beyond the range. It is shown that the NFDTD presented in this paper has a great advantage over the TFDTD and the NFDTD has a wide applicability in calculating the lightning electromagnetic field.