换流变压器阀侧绕组故障分析  

Fault Analysis for Valve Side Winding of Converter Transformer

作　　者：张艳霞[1] 韩悦 成雅超 刘凯祥 ZHANG Yanxia;HAN Yue;CHENG Yachao;LIU Kaixiang(Key Laboratory of Smart Grid(Tianjin University),Ministry of Education,Nankai District,Tianjin 300072,China)

机构地区：[1]智能电网教育部重点实验室(天津大学),天津市南开区300072

出　　处：《电网技术》2022年第7期2794-2803,共10页Power System Technology

摘　　要：该文以柔性直流系统的三相两电平电压源换流器伪双极结构为例,分析了换流变压器阀侧绕组故障的特征。根据换流阀具备的8种导通情况,将其工作状态分为环路状态、电网充电状态和充电环路复合状态。在此基础上,依据不同故障发生时刻换流变阀侧的不同工作状态,对阀侧绕组发生不同类型短路的故障特征进行了归类分析,并据故障电流通路所对应的等效电路列写回路电流方程,从而寻找电气量特征。利用PSCAD/EMTDC仿真验证了故障特性,为分析换流变保护动作性能和新原理研究提供了依据。In this paper,the fault characteristics of valve side winding in the converter transformer is analyzed based on the pseudo bipolar structure of the three-phase two-level voltage source converter in the VSC-HVDC(voltage source converter based high voltage direct current transmission).Based on the eight conduction conditions of the converter valves,the normal working state of valve side of the converter transformer is divided into the loop state,the grid charging state and the charging-loop compound state.According to the different working states of the valve side of the transformer when the fault occurs at different time,the fault characteristics in different types of short circuit in the valve side winding are classified and analyzed,and the circuit current equation is established in the light of the equivalent circuit corresponding to the fault current path so as to find the characteristics of electric quantity.The fault characteristics are verified by the PSCAD/EMTDC simulation,which provides a basis for analyzing the operation performance and new principle research of the converter transformer protection.

关 键 词：柔性直流输电 换流变压器 阀侧绕组 故障分析 故障特征 

分 类 号：TM721[电气工程—电力系统及自动化]