N层土壤模型下HVDC系统大地回路运行时ESP分布研究

ESP distribution analysis in HVDC system with the operation of ground return in N-layer soil model

分析High Voltage Direct Current(HVDC)输电系统大地回路运行时地表电位分布,是评估地下金属管道腐蚀、变压器直流偏磁、通信干扰等不良效应受接地极电流影响的前提。文中利用镜像法和电磁波的折射、反射规律,推导出N层垂直和水平复合分层的地表电位的解析公式,然后利用这个解析公式解决华东地区地表电位分布的实际问题,通过不同模型计算结果的反馈得到华东地区理想的仿真模型,最后用多项式插值将电位曲线进行拟合,得到华东地区地表电位的一般函数表达式。

The analysis on earth surface potential （ESP） distribution in high voltage direct current （HVDC） transmis- sion system of operation with ground return is the premise of evaluating underground metal pipeline corrosion, trans- former DC bias, communication interference and other adverse effects under the influence of ground electrode current. This paper deduces the resulting formula of ESP in N-layer soil model by using images method, the law of transmis- sion-reflection and transmission-refraction of electromagnetic wave. After that, a practical problem of East China ESP is solved by the formula. In addition, the feedback about simulation results of different soil models of East China is made to get an ideal model. Finally, the general function expression of the East China ESP is presented by using poly- nomial interpolation to fit potential curve.