新型平衡牵引变压器负序电流仿真计算与分析

电气化铁道属于不对称供电系统,为降低牵引变压器及接线方式对电力系统的负序影响,经电力、铁路部门研究,提出采用新型平衡牵引变压器,该牵引变压器采用中间带抽头的Scott接线方式。根据其接线方式及特点,分析其电气特性,推导一次侧与二次侧绕组电流的变换关系、负序电流计算公式,并以工程实例进行该牵引变压器负序电流仿真计算。电流仿真计算表明:由于牵引变电所两供电臂电流的差异,采用不同的牵引变压器及接线方式,产生的负序电流是不同的,新型平衡牵引变压器及接线方式产生的负序电流,在一定的持续时间内介于V/V接线牵引变压器和单相接线牵引变压器之间。

The analysis on negative current of a new balance transformer

Electric railway is non - balance power system . To reduce the influence of high - speed railway NPS （ Negative Phase Sequence）, railway and power workers studied out the 220kV balance transformer. This transformer is Scott transformer with secondary midpoint draw - out. According the mode of connection and characteristic, this article analyses the electric characteristic, deduces the current relation of first side and secondary side winding, deduces the NPS computational formula, calculate the NPS of this transformer base on engineering project. From the circulating and simulation of NPS, this article gets the points ： because current of the two feeding section is different, the NPS is different from the several modes connection of transformer. The NPS of New balance transformer is in the middle of V/V transformer and single phase transformer when the duration time is given.