变压器饱和对交流电网直流电流分布的影响  

Effect of Transformer Saturation on the DC Distribution of AC Power System

作　　者：翁汉琍[1] 杨国稳 相艳会[3] 潘美[1] 林湘宁[1] 

机构地区：[1]三峡大学电气与新能源学院,宜昌443002 [2]国网浙江省电力公司温岭市供电公司,温岭317500 [3]国网湖北省电力公司黄冈供电公司,黄冈438000

出　　处：《高电压技术》2016年第10期3295-3300,共6页High Voltage Engineering

基　　金：国家自然科学基金(51607106);三峡大学人才科研启动基金(KJ2014B043)~~

摘　　要：针对直流偏磁影响下变压器励磁支路饱和从而导致励磁电流半波饱和出现直流分量的现象,研究该直流分量对变压器中性点直流电流分布的影响。分析了三相变压器在遭受直流偏磁影响时中性点直流电流的形成机理,基于PSCAD/EMTDC平台搭建变压器直流偏磁模型,分别从计及饱和不计及饱和两种工况分析直流偏磁下变压器中性点直流电流的情况,再根据所得结果修正不计及饱和因素的Y地区电网直流偏磁模型所得的变压器中性点直流电流。仿真结果表明变压器励磁支路饱和特性对变压器中性点直流电流有助增作用,计及变压器饱和特性时可以提高交流电网直流电流分布的预测精度。Aiming at the phenomenon that occurrence of half-wave saturation in transformer magnetizing current can be caused by magnetizing branch saturation under DC bias conditions, which will result in the DC component current emergence in magnetizing current, we researched the effect of the DC component on the distribution of the DC bias current in the transformer neutral point. The formation mechanism of DC current in the neutral point of three-phase transformer in the case of DC bias was analyzed. A transformer DC bias simulation model was established based on the PSCAD/EMTDC platform.Moreover, the compositions of DC currents in transformer neutral point with DC bias considering and regardless of the transformer saturation were studied, respectively. Furthermore, DC distributions in transformer neutral points of Y region, which was calculated on the basis of DC bias simulation model without taking the transformer saturation into account, could be amended. Simulation results show that transformer saturation has infeed effect on the DC bias in transformer neutral point. In addition, the prediction accuracy of DC distribution in the AC power system can be improved after taking transformer magnetizing branch saturation into account.

关 键 词：变压器 直流偏磁 励磁支路饱和 助增作用 直流电流分布预测精度 

分 类 号：TM721.1[电气工程—电力系统及自动化]