摘要
提出了一种新颖的星形一双梯形接线三相变四相或三相变两相平衡变压器。该变压器采用三相三柱铁心结构,一次侧构成三相系统,采用星形接线,二次侧绕组采用闭合双梯形接线,便于3次谐波电流流通,改善电压波形。2个梯形形状相同,并具有共同的底边,其中点为四相系统的公共点。2个梯形的4个顶点构成四相或两相系统。该文阐述了该变压器的基本原理、接线方案和基本方程,导出了一二次侧绕组的电流关系,得出了一次侧中性点电流为零的平衡条件和短路阻抗关系。该变压器铁心及绕组结构简单,材料利用率为100%,特别适合于作为四相输电系统及电气化铁路AT供电方式的主变压器。
A novel three-phase to four-phase or two-phase balance transformer connected in Y and double trapezoids has been presented. Three phase three-leg core is adopted in this transformer. Three systems consist of the primary windings connected in Y. The secondary windings are connected by the closed double trapezoids so that the third harmonic currents can flow, so voltages are approximate sine waves. Two trapezoids are the same in shape and hold a common winding as the bottom side, while the midpoint of the common winding is the ground of four phase systems. Four apexes of double trapezoids compose four phase or two phase systems. This paper expounds the principle, the connected scheme and basic equations of this transformer. The current relationships of the primary windings and second windings are derived from the basic equations. The balance condition, i.e., the neutral current in the primary side is zero, and the relationships of short impedances are presented. This transformer is simple in structure of iron-core and windings, and its material utilization ratio is 100%. This transformer may be utilized to either four-phase transmission systems or autotransformer （AT） traction power supply systems in electric railways.
出处
《中国电机工程学报》
EI
CSCD
北大核心
2007年第3期78-82,共5页
Proceedings of the CSEE
基金
国家自然科学基金项目(50247006)
教育部重点研究项目(102174)
湖南省重大科技专项(05GK1002-1)~~
关键词
平衡变压器
星形-双梯形
四相输电系统
电气化铁路
balance transformer
Y and double trapezoid
four phase transmission system
electric railway
