一种基于消弧线圈和静止同步补偿器协同作用的配电网消弧结构与方法  

An Arc-Suppression Method Based on the Coordinated Operation of the Petersen Coil and the Static Synchronous Compensator in Distribution Networks

作　　者：周兴达 陆帅 Zhou Xingda;Lu Shuai(State Key Laboratory of Power Transmission Equipment and System Security Chongqing University,Chongqing 400044 China)

机构地区：[1]输配电装备及系统安全与新技术国家重点实验室(重庆大学),重庆400044

出　　处：《电工技术学报》2019年第6期1251-1262,共12页Transactions of China Electrotechnical Society

摘　　要：由于线路对地电容的存在,中性点非有效接地系统发生单相线路接地故障后会引起较大的接地故障电流甚至弧光。本文提出一种基于消弧线圈和三相级联H桥静止同步补偿器(STATCOM)协同作用的新型配电网单相线路接地故障消弧结构和方法,该结构将STATCOM中性点通过消弧线圈接地,当单相接地故障发生后,消弧线圈补偿接地故障电流中的大部分基波分量,另外通过对STATCOM增加共模控制回路,来补偿接地故障电流中剩余的基波、谐波和有功分量。实现了无源与有源消弧措施的结合,提升了单相接地故障电流的补偿效果,避免了使用STATCOM中性点直接接地来补偿接地故障电流时直流侧电压大幅升高和所需级联H桥单元增加的问题。另一方面该方法能够同时实现STATCOM无功补偿功能与消弧功能,提高了设备利用率。最后,通过Matlab/Simulink仿真和低压版实验系统的结果验证了该方法的可行性和有效性。Due to the existence of line-to-ground capacitance,a single line to ground fault will cause a large ground fault current in the un-grounded distribution networks.If not instantly suppressed,the sustained arc from the fault current will cause permanent damages.This paper proposes an effective arc-suppression method based on the coordinated operation of a petersen coil and a three-phase cascaded H-bridge static synchronous compensator(STATCOM)in distribution networks.The neutral point of the STATCOM is connected to the ground through the petersen coil.When the single line to ground fault occurs,the petersen coil compensates most of the fundamental component of the ground current,while a new set of the common mode based controls are added into the existing STATCOM controller to compensate the remaining fundamental,harmonics and active components in the ground fault current,so that the arc current is instantly eliminated.The proposed series connection of the passive arc-suppression to the active arc-suppression by the STATCOM,not only guarantees the dynamic response of the ground fault current compensation,it also avoids the large increase of dc-link voltage when the neutral point of STATCOM is directly connected to the ground for active arc-suppression.Finally,the feasibility and effectiveness of the proposed method are successfully verified by the Matlab/Simulink simulation and experimental results in this paper.

关 键 词：中性点非有效接地系统 单相线路接地故障 消弧线圈 STATCOM 共模控制 

分 类 号：TM726.1[电气工程—电力系统及自动化]