基于列车运行图法的AT牵引供电系统负序影响

N-Seq influence of AT traction power supply system based on train diagram method

为研究自耦变压器(AT)牵引供电系统对地区电网造成的负序(N-Seq)影响,首先讨论了AT牵引供电系统、单相VV接线牵引变电站的电流分布,推导得出了负序电流、三相电压不平衡度的计算公式;然后结合"列车运行图法"开发了相应的仿真程序;最后通过一个实际算例,得到了实时电压不平衡度曲线,指出了负序大小的影响因素及相应措施。研究结果表明,该仿真程序可以实时地评估负序影响。

In order to study the negative-sequence（N-Seq） influence to regional power grid caused by autotransformer（AT） traction power supply system, formulas of N-Seq current and three-phase voltage imbalance were derived, based on current distribution analysis of AT traction power supply system and single-phase VV-configuration train substation. Employing the ＂train diagram＂ method, the real-time voltage-imbalance curve was obtained in a simulation study, as well as the factors that influence N-Seq and some measures to restrain it. The simulation results also indicate the effectiveness of applying this method to evaluate the N-Seq influence in real time.