地上绝缘导线电磁问题分析

Electromagnetic Problem Analysis of Insulated Wires Above Ground

提出一个快速有效的联合模型用于地上绝缘导线的电磁问题分析。耗损土壤的影响用镜像模型表示;导线绝缘层等效为极化电荷。在应用矩量法建立地上绝缘导线感应电流的计算模型之后,进一步推导了导线周围近场的计算公式。经过合理的简化,矩量法矩阵元素可以表示为代数解析式,从而大大提高了模型的计算速度。最后,应用严格模型结果及实验结果对本文方法的有效精确性进行了验证,并将该方法用于实际问题的分析研究。

In this paper,a fast model was proposed for the electromagnetic coupling analysis of insulated wires above a lossy ground. Lossy ground is modeled by images, and insulation by equivalent polarization charges. After moment method modeling for induced current calculation, formulas for the near electric field around insulated wires are derived. With reasonable approximation, the impedance elements can be reduced to closed form expressions both for current and electric field calculation. By using these, the computation speed can be improved enormously. Finally, comparisons are made to validate the efficiency and accuracy of this method; and furthermore, this method is put into practical uses.