摘要
十字交叉接线牵引变压器实际上是三相三绕组变压器,已应用于我国电气化铁道2×25kV自耦变压器(AT)供电系统。针对其特殊的接线形式,采用了以磁势平衡方程、绕组接线方程、端口输出方程和电压传递方程为基础的多绕组变压器系统化分析方法,阐明了负荷电流和可能的零序电流在绕组中的分配关系;推导出了二次侧端口电压方程;给出了该变压器在相坐标下的节点导纳矩阵,以便同电力系统和牵引网接口进行有关分析。最后,分析了省掉变电所内AT和中性点不接地运行等问题。
The cross-connected transformer, which is actually an YNd11d1 three-phase three-winding transformer, has been used in a 2?5kV AT traction network of electrified railway in China. A systematic analysis method, based on the magnetomotive force balance equations, winding connection equations, output-port equations and voltage transfer equations, has been adopted to deal with the distinct winding connection of the transformer. The distribution of load currents and possible zero-sequence current in windings is analyzed; voltage output equations in secondary side are derived. The nodal admittance matrix in phase coordinates of the transformer is obtained, which can be conveniently used to interface with power systems and traction networks in related analyses. Finally, the problems of omitting substation ATs and operating performance with neutral isolation are analyzed.
出处
《电工技术学报》
EI
CSCD
北大核心
2004年第9期11-17,共7页
Transactions of China Electrotechnical Society
