中国电机工程学报2023，Vol.43Issue(24)：9546-9556,中插14,12.DOI:10.13334/j.0258-8013.pcsee.220818
多端柔性直流电网线路故障暂态等值电路及暂态特征分析
Study on the Transient Equivalent Circuits and the Transient Characteristics of Multi-terminal Flexible DC Grids After Line Faults
摘要
Abstract
The problem of line protection is the bottleneck of the development of a flexible DC grid.As the theoretical basis of the line protection,the equivalent circuit and transient characteristics after line fault need systematic analysis.This research will provide the cornerstone for the design of new line protection.Using the transient model of the converter,model of transmission line,and the boundary conditions of the fault point,the transient equivalent circuit after decoupling into line-zero mode is established.The transfer functions of the fault traveling wave at the faulty line terminal,the DC bus,and the healthy line terminal are obtained,and the transient characteristics of the initial fault traveling wave are analyzed.Besides,the multiple refractions and reflections of fault traveling waves between inductive line terminal and fault point are analyzed,the change law of the waveform after refraction and reflection is obtained,and the aliasing phenomenon between line-mode and zero-mode at fault point is analyzed.Finally,A four-terminal simulation model built in PSCAD/EMTDC demonstrates the correctness through the comparative analysis of the calculation and the simulation value.The characteristics of the waveform are analyzed when the parameters of the converter and current limiting reactor are changed.关键词
柔性直流电网/暂态等值电路/暂态特征/故障行波/传递函数/线路故障Key words
flexible DC grid/transient equivalent circuit/transient characteristics/fault traveling wave/transfer function/line faults分类
信息技术与安全科学引用本文复制引用
余修勇,顾菊平,张新松,茅靖峰..多端柔性直流电网线路故障暂态等值电路及暂态特征分析[J].中国电机工程学报,2023,43(24):9546-9556,中插14,12.基金项目
国家自然科学基金项目(U2066203,51721005).Project Supported by National Natural Science Foundation of China(U2066203,51721005). （U2066203,51721005）
