摘要
换相失败是晶闸管换流阀逆变器的常见故障,为提高直流系统抵御换相失败的能力,实际工程中直流控制保护系统基于换流母线电压提出了许多预防换相失败的算法,然而在直流分层接入方式下,常规预防换相失败的控制功能在某些工况下失效。该文建立特高压直流分层接入系统电磁暂态仿真模型,基于分层接入相互作用因子和换流母线谐波特性,研究预防换相失败的优化措施。提出高低端换流器预防换相失败的协调优化措施和基于滑窗离散傅里叶变换(discrete Fourier transformation,DFT)谐波电压检测的预防换相失败控制算法。研究结果表明:该方法能够在交流系统故障和变压器充电过程减小直流系统发生换相失败的几率。
Commutation failures is regular faults of line-commutated converters at the inverter stations.To reduce the.possibility of commutation failures,many prediction algorithms based on alternative current(AC)voltage detection have been developed for high voltage direct current(HVDC) control and protection systems.Nevertheless,the conventional commutation failure predictive method was not effective for UHVDC projects with hierarchical connection structure in some cases.In this paper,a simulation model of UHVDC transmission with hierarchical connection was established in the electromagnetic transient program(EMTDC).An improved commutation failure predictionalgorithm based on the hierarchical accessinteraction factor and the harmonic characteristics of the converter bus voltage were developed. Meanwhile,acoordinatedoptimizationmethodfor commutation failure prediction for high and low voltage converter,and a sliding-window iterative algorithm of discrete Fourier transformation(DFT)were developed for detecting the voltage harmonic.This method was proved to be an effective solution,which reduces the probability of commutation failures in cases of AC system faults and transformer energizing at the inverter stations.
作者
李新年
陈树勇
李凤祁
雷霄
周晖
林少伯
LI Xirmian;CHEN Shuyong;LI Fengqi;LEI Xiao;ZHOU Hui;LIN Shaobo(School of Electrical Engineering,Beijing Jiaotong University,Haidian District,Beijing100044,China;State Key Laboratory of Power Grid Safety and Energy Conservation(China Electric Power Research Institute),Haidian District,Beijing100192,China;State Grid Operation Company,Xicheng District,Beijing100052,China)
出处
《中国电机工程学报》
EI
CSCD
北大核心
2018年第22期6563-6572,共10页
Proceedings of the CSEE
基金
国家电网公司科技项目(XT71-15-045)~~
关键词
特高压直流输电
换相失败
分层接入
谐波检测
预测控制
ultra high voltage direct current(UHVDC)
commutationfailure
hierarchicalconnection
harmonic detection
predictive control
