The Finite-Difference Time-Domain (FDTD) solutions of lightning-induced voltages due to nearby lightning return stroke on overhead power lines are proposed by Agrawal et al. and Paolone et al. In this paper, we develop above FDTD methods by using the higher-order FDTD method with second-order accuracy in time and eighth-order in space. The algorithm is applied to solve field-to-transmission line coupling equations of multiconductor transmission lines (MTL) that include both forms of the vertically- and horizontally- configured three-phase lines. The computation results with various FDTD schemes are illustrated and compared on graphs. From these results, it can be shown the influences of the phase-conductor position and the higher-order FDTD schemes on the peak value of total induced voltages at the first few microseconds. Finally, this algorithm is very suitable for studying the solutions of telegraphy or EM coupling equations of all transmission lines in EMC problems with higher accuracy.
