三相变四相变压器在AT供电系统中的应用研究

给出了三相变四相变压器在电气化铁道AT牵引变电所中的接线形式，针对不同负荷条件下的负序电流进行了计算和分析，以曲线形式描述了三相侧电流不对称度的变化规律，分析了三相变四相变压器在电气化铁路应用中的容量选择问题。与其它牵引变压器相比，三相变四相变压器具有较好的结构和平衡特性，可以用于电气化铁路AT供电。

STUDY ON THE APPLICATION TO AT POWER SUPPLY SYSTEM OF THREE-PHASE TO FOUR-PHASE TRANSFORMER

The connection scheme of electric railway traction substation with AT power supply system used three-phase to four-phase transformer is proposed. The negative sequence currents under different loads are calculated. And the rules of the current asymmetry degree at the three-phase side are described in the form of curves. The problem of capacity selection of three-phase to four-phase transformer used in electric railway is analyzed. Because of the better structure and balance characteristic compared with other transformer used in electric railway, the three-phase to four-phase transformer can apply to AT power supply system.