输电线路地线对流入变压器中性点直流电流的影响

Impact of Ground Wire in HVDC Transmission Line on Direct Current Flowing into Neutral Point of Power Transformer

交流变压器中性点流入直流电流会导致变压器偏磁等一系列不良后果。基于特定模型,使用场路耦合的方法研究了500kV直流输电线路以大地为回路运行时与变电站相连的输电线路地线上流过的直流电流对流过变压器中性点的总直流电流的影响。研究发现,线路地线对流入变压器中性点的直流电流影响很小,因此在进一步研究流入交流变电站变压器中性点的直流电流时可以忽略线路地线,从而可简化分析模型。

A series of harmful results, e.g., DC bias ofpower transformer, may occur if direct current exceeding acertain value flows into the neutral point of power transformerin AC power system. Based on a specified model the impact ofthe direct current flowing through the ground wire of 500kVHVDC transmission line on the total direct current flowingthrough the neutral point of power transformer is researched bythe coupling method of electric field with electric circuit. It isdiscovered from the research result that...