【摘要】 针对特高压直流输电系统单极大地回路运行时会引起直流偏磁等严重后果的问题,提出用有限元方法来分析水平分层土壤的地表电位分布规律;输电线路沿途含有山川、河流、湖泊对地表电位分布的影响,以及靠近沿海地区地电位的分布情况。研究结果表明:在处理水平分层土壤模型时有限元分析的结果很好地反映了地电位分布的规律;地理环境的变化对地电位只在小范围内有一定影响,在整体上对地电位分布影响不大;沿海地区的地表电位变化明显,变化率大于非沿海区域,解释了沿海地区直流偏磁严重的原因。更多还原

【Abstract】 Ultra-high voltage current(UHVDC) transmission system operates in ground-return mode may cause very serious issues,such as DC biases of transformers.Based on finite element method,potential distribution of horizontal layered soil surface is analyzed.Meanwhile,the earth potential distribution affected by mountains,rivers,lakes and oceans are analyzed.The results well reflect the law of earth surface potential(ESP) distribution by using finite element method.Geographic variations only have certain influence on the small area of earth surface potential,while little effect on the whole earth surface potential.Surface potential change rate in coastal areas is greater than that in the inland,which explains the reason that DC biases of transformers always appears in coastal areas.更多还原