FDTD Calculation of Transient Electromagnetic Fields in the Grounding System of Wind Towers Due to Direct Lightning Strikes

ABSTRACT

Lightning protection system (LPS) for wind power generation has become an important public issue due to greatly increasing installations of wind turbines (WTs) worldwide. Grounding system is one of the most important components required for appropriate LPS for WTs. Although the finite-difference time-domain (FDTD) method for solving Maxwell`s equations is difficult for computing earth potential rise (EPR) and transient grounding resistance (TGR), this method is used in this paper to compute EPR and TGR for different configurations of the grounding system of WTs because FDTD method can efficiently deal with the three-dimensional geometrical configurations of an investigated structure unlike electromagnetic transient programs (EMTP).

Keywords:

Earth potential rise (EPR), electromagnetic transient programs (EMTP), finite-difference time-domain (FDTD), grounding system, hybrid arrangement, thin wire, transient grounding resistance (TGR), type A arrangement, type B arrangement.