水平接地极泄散雷电流对临近埋地管道危害影响分析

Analysis on hazard influence of dispersal lightning current through horizontal grounding electrode on adjacent buried pipeline

为分析水平接地极泄散雷电流对临近埋地管道产生的暂态电磁干扰危害,通过EMTP软件建立水平接地极和埋地管道模型,考虑水平接地极与管道间的感性耦合和阻性耦合,采用多元回归分析法讨论土壤电阻率、水平接地极与管道间距、管道埋深、雷电流幅值等因素对管道防腐层感应电压的影响,最后讨论感应电流对管道腐蚀的影响。结果表明:离雷电流注入点越远,管道防腐层感应电流和感应电压幅值越低;感应电压受土壤电阻率、水平接地极与管道水平间距、管道埋深、雷电流幅值等因素影响明显,与土壤电阻率和雷电流幅值呈正相关,与管道埋深和水平接地极与管道水平间距呈负相关;土壤电阻率对管道腐蚀程度影响较大,土壤电阻率越低,管道腐蚀越严重;为保护防腐层和管道安全,水平接地极与管道间需保持一定安全距离。

In order to analyze the hazard of transient electromagnetic interference on the adjacent buried pipeline caused by the dispersal lightning current through the horizontal grounding electrode,the models of horizontal grounding electrode and buried pipeline were established by using the EMTP software.Considering the inductive coupling and resistive coupling between the horizontal grounding electrode and pipeline,the influence of soil resistivity,separated distance between the horizontal grounding electrode and pipeline,buried depth of pipeline,lightning current amplitude and other factors on the induced voltage of pipeline corrosion protection layer were analyzed by using the multiple regression analysis method,and the influence of induced current on the pipeline corrosion was discussed.The results showed that the farther away from the injection point of lightning current,the lower the amplitudes of induced current and induced voltage of the pipeline corrosion protection layer.The induced voltage was obviously affected by the factors of soil resistivity,separated distance between the horizontal grounding electrode and pipeline,buried depth of pipeline,lightning current amplitude,and it was positively correlated with the soil resistivity and the lightning current amplitude,while negatively correlated with the separated distance between the horizontal grounding electrode and pipeline and the buried depth of pipeline.The soil resistivity greatly affected the corrosion degree of pipeline,the lower the soil resistivity,the more serious the pipeline corrosion.In order to protect the safety of corrosion protection layer and pipeline,a certain safety distance should be maintained between the horizontal grounding electrode and pipeline.