三相五柱变压器直流偏磁计算.pdf

第30 卷 第1 期 中 国 电 机 工 程 学 报 Vol.30 No.1 Jan.5, 2010 2010 年1 月5 日 Proceedings of the CSEE ©2010 Chin.Soc.for Elec.Eng. 127 0258-8013 (2010) 01-0127-05 TM 153 TM 41 A 470 40 文章编号： 中图分类号： ； 文献标志码： 学科分类号： ⋅ 三相五柱变压器直流偏磁计算研究 李晓萍，文习山 (武汉大学电气工程学院，湖北省 武汉市 430072) DC Bias Computation Study on Three-phase Five Limbs Transformer LI Xiao-ping, WEN Xi-shan (School of Electrical Engineering, Wuhan University, Wuhan 430072, Hubei Province, China) ABSTRACT: The DC current flows into the earth as DC 相五柱变压器各铁心柱的磁场强度进行了计算，无直流下， transmission system runs in monopole. At the same time the 端轭的磁场强度最大，旁柱的磁场强度最小，直流入侵，各 DC current inrush the AC transmission system through the 铁心柱的磁场强度峰值随直流电流非线性增长，旁柱和端轭 earthed neutral point of transformer, which result in DC bias of 磁场强度的增长速度较三相柱快。 AC transformer and consequently harmonics are produced. In 关键词：三相五柱变压器；直流偏磁；励磁电流；谐波；磁 previous research, DC bias problem on transformers of single 场强度 phase and three-phase three limbs had been studied and had got some regularities. In this paper, DC bias on three-phase five 0 引言 limbs transformer had been studied by calculation. In the 为满足日益增长的用电需求，我国在原有交流 process of calculation, Maxell formula was used instead of magnetic circuit formula, coupling with electric circuit, 电网的基础上，大力发展远距离直流输电。直流输 combining with nonlinear characteristics curve of tran