采用新穎格式FDTD計算大地垂直分層雷電電磁場
金濤斌1，王龍飛2，劉正文2，羅雨2
（1 呼和浩特市城市軌道交通建設管理有限責任公司，內蒙古 呼和浩特 010000；2 北京石油化工學院 機械工程學院，北京 102617）
摘 要：雷電電磁脈沖會通過耦合作用產生瞬時高電壓和大電流干擾，研究雷電放電過程并快速、精確計算雷電電磁場分布，可有效減少設備損失，降低事故率。在二維柱坐標系下，提出了一種新穎格式的FDTD算法，能夠更精確計算大地垂直分層且分界面離雷電通道較近情況下的雷電電磁場分布，計算結果表明：對大地垂直分層且分界面離雷電通道較近時，計算離雷電通道50 m范圍內的雷電電磁場，新穎FDTD的計算精度較傳統FDTD有顯著提高，而計算離雷電通道50 m范圍外的雷電電磁場，其計算結果與傳統FDTD計算結果趨于一致，這說明提出的新穎格式FDTD具有傳統FDTD的所有優點，并且在計算大地垂直分層情況下，較傳統FDTD具有更高的計算精度，在計算雷電電磁場時，具有更廣泛的適用性。
關鍵詞：雷電電磁脈沖；雷電電磁場；二維柱坐標系；大地垂直分層
中圖分類號：TM863 文獻標識碼：A 文章編號：1007-3175(2020)07-0024-05
Calculation of the Lightning Electromagnetic Field for Vertically Stratified Ground Using Novel Scheme FDTD
JIN Tao-bin1, WANG Long-fei2, LIU Zheng-wen2, LUO Yu2
（1 Hohhot Rail Transit Construction Management Co., Ltd, Hohhot 010000, China;
2 School of Mechanical Engineering, Beijing Institute of Petrochemical Technology, Beijing 102617, China）
Abstract: Lightning electromagnetic pulses will generate instantaneous high voltage and high current interference through coupling, studying on the lightning process and calculating the lightning electromagnetic field quickly and accurately can effectively reduce equipment losses and accident rate.In the two dimensional cylindrical coordinate system, a novel format of FDTD (NFDTD) algorithm is proposed which can calculate the lightning electromagnetic field distribution more accurately in the case that the ground is vertically layered and the interface is near 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 50 m 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 has a great advantage over the TFDTD and the NFDTD has a wide applicability in calculating the lightning electromagnetic field.
Key words: lightning electromagnetic pulse; lightning electromagnetic field; 2-D cylindrical coordinate system; vertical stratification of the earth
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