考虑地铁杂散电流影响的变压器直流偏磁电流建模方法  

Modeling for the DC bias current of transformer caused by the metro stray current

作　　者：彭平 曾祥君[2] 倪砚茹 喻锟 冷阳 周卫华 谢耀恒 PENG Ping;ZENG Xiangjun;NI Yanru;YU Kun;LENG Yang;ZHOU Weihua;XIE Yaoheng(Electric Power Science Research Institute,State Grid Hunan Electric Power Co.,Ltd.,Changsha 410114,China;School of Electrical and Information Engineering,Changsha University of Science and Technology,Changsha 410114,China)

机构地区：[1]国网湖南省电力有限公司电力科学研究院,湖南长沙410114 [2]长沙理工大学电气与信息工程学院,湖南长沙410114

出　　处：《电力科学与技术学报》2021年第1期192-198,共7页Journal of Electric Power Science And Technology

基　　金：国网湖南省电力有限公司科技项目(5216A5160033)。

摘　　要：地铁杂散电流会由土壤中的接地网流经变压器中性点从而引发变压器直流偏磁现象。为研究地铁杂散电流对变压器直流偏磁的作用机理,从地铁牵引电流、"钢轨—排流网—大地"杂散电流泄露路径、直流偏磁电流回路三方面等效考虑,搭建杂散电流引起变压器直流偏磁的电阻模型,建立变压器中性点电流随时间、地铁位置变化的动态方程,以LU分解求解得到地铁沿线流经变压器中性点的杂散电流。利用CDEGS搭建地铁运行与变压器仿真模型,对比分析变压器中性点电流的仿真结果与所提建模方法的计算结果,所搭模型误差小,能够准确计算流经变压器中性点的杂散直流量,可有效应用于变压器受地铁杂散电流引发直流偏磁的影响分析。The metro stray current can flow through the neutral point of the transformer from the grounding grid in the soil,and then cause the transformer DC bias phenomenon.In order to effectively evaluate the influence of metro stray currents on transformers,a resistance model for the transformer DC bias caused by the stray current is established by considering the traction current in metro,the"rail-current drainage net-earth"metro system structure,and the DC bias current loop.Then the dynamic equation of transformer neutral point current with time and metro train position is established,and the neutral point current can be solved by the LU decomposition.The software CDEGS is utilized to build the train and transformer simulation model.The transformer neutral point current between the simulation results and the calculation results of the proposed modeling method are comparative analyzed,and the model error is small.Therefore,it can be effectively applied to the evaluation of transformers affected by metro stray current.

关 键 词：地铁 杂散电流 变压器直流偏磁 变压器中性点电流 

分 类 号：TM401.1[电气工程—电器]