基于有源逆变分相注入的电压消弧与位移电压抑制方法  

Voltage arc suppression and displacement voltage suppression method based on active inverter separate phase injection

作　　者：梁洪湘 曾祥君[1] 喻锟 向国杰 熊一帆 Liang Hongxiang;Zeng Xiangjun;Yu Kun;Xiang Guojie;Xiong Yifan(School of Electrical and Information Engineering,Changsha University of Science and Technology,Changsha 410114,China)

机构地区：[1]长沙理工大学电气与信息工程学院,长沙410114

出　　处：《电测与仪表》2022年第1期51-60,共10页Electrical Measurement & Instrumentation

基　　金：国家自然科学基金重点项目(51737002)。

摘　　要：针对配电网发生单相接地故障时极易产生电弧,以及在非故障情况下由于三相对地参数不相同而导致的三相电压不对称问题,提出一种基于有源逆变分相注入的电压消弧与位移电压抑制方法。在三相线路首端分别挂接有源逆变,通过脉宽调制信号控制有源逆变电路的输出电流。当配电网出现单相接地故障时,有源逆变向系统分相注入零序电流,通过零序回路调节故障相电压,将故障相电压钳制为0 V,破坏电弧重燃条件。在非故障情况下,当配电网对地参数不对称而导致三相电压不对称时,有源逆变向系统分相注入零序电流,通过零序回路调节中性点电压,钳制中性点电压为0 V,实现中性点位移电压抑制。仿真结果表明,该方法可有效破坏电弧重新燃弧条件以及抑制中性点位移电压。Aiming at the problem of arc generation when single-phase grounding fault occurs in distribution network and three-phase voltage asymmetry caused by different parameters of three-phase to ground in non-fault condition,a method of voltage arc suppression and displacement voltage suppression based on active inverters phased injection is proposed in this paper.Active inverter is connected to the first end of the three-phase line,and the output current of the active inverter circuit is controlled by the pulse width modulation signal.When a single-phase ground fault occurs in the distribution network,the active inverter split phase injects zero-sequence current into the system,adjusts the fault phase voltage through the zero-sequence loop,clamps the fault point voltage to 0 V,and destroys the arc re-ignition condition.In the case of non-fault,when the three-phase voltage is asymmetrical due to the asymmetrical parameters of the distribution network to the ground,the active inverters inject zero-sequence current into the system separately,adjust the neutral-point voltage through the zero-sequence circuit,clamp the neutral-point voltage to 0 V,and realize the neutral-point displacement voltage suppression.The simulation results show that the method can effectively destroy the arc re-burning conditions and suppress the neutral point displacement voltage.

关 键 词：配电网 单相接地故障 电压消弧 三相不平衡 

分 类 号：TM71[电气工程—电力系统及自动化]