摘要
高压直流输电系统逆变侧不对称故障会造成换流阀换相电压相位发生偏移,进而引起换相失败的发生,严重影响了系统的稳定运行。为此,对不对称故障下的换相电压偏移量特性进行研究,基于电力系统暂态分析方法,对不对称故障下高压直流输电系统进行正负零序分解,推导出YNy0接线和YNd1接线换流变压器阀侧三相电压幅值、相位的计算公式,得到不对称故障下12脉动换流阀换相电压的最大偏移量,并对换流变网侧交流母线线电压幅值进行计算,通过MATLAB解析计算分析不同类型故障接地阻抗下,换流阀换相电压偏移量的变化特性。PSCAD/EMTDC电磁暂态仿真结果证明了文中所分析换相电压偏移量影响特性的正确性。
Asymmetrical faults on the inverter side of the high voltage direct current(HVDC)transmission system will lead to the phase offset of commutation voltage of converter valve,which will cause commutation failures and seriously affect the stable operation of the system.So it is necessary to study the phase offset characteristics of commutation voltage under asymmetric faults.Based on the transient analysis method of the power system,the positive-,negative-and zero-sequence decompositions of the HVDC transmission system under asymmetric faults are carried out,and the calculation formulas for the amplitude and phase of the three-phase voltage on the valve side of the converter transformers for YNy0 and YNd1 wiring are derived,and the maximum deviation of the commutation voltage of the 12-pulsation converter valve under an asymmetric fault is obtained.In addition,the amplitude of the AC bus voltage on the grid side of the converter is calculated,based on MATLAB simulation software,the characteristic variation of commutation voltage offset of converter valve with different types of ground fault impedance are analyzed.The PSCAD/EMTDC electromagnetic transient simulation results prove the correctness of the influence characteristics of commutation voltage offset analyzed in this paper.
作者
黄梦华
傅闯
汪娟娟
杨健
李欢
文兆新
HUANG Menghua;FU Chuang;WANG Juanjuan;YANG Jian;LI Huan;WEN Zhaoxin(Guangdong Electric Power Research Institute Energy Technology Co.,Ltd.,Guangzhou 510080,China;State Key Laboratory of HVDC,Electric Power Research Institute of China Southern Power Grid,Guangzhou 510663,China;School of Electric Power,South China University of Technology,Guangzhou 510641,China)
出处
《电力系统自动化》
EI
CSCD
北大核心
2020年第12期162-168,共7页
Automation of Electric Power Systems
基金
国家自然科学基金资助项目(51777079)
国家自然科学基金委员会-国家电网公司智能电网联合基金项目(U1766213)
南方电网公司重点实验室项目(SKLHVDC-2019-KF-19)。
关键词
高压直流
单相接地故障
换相电压偏移量
接地阻抗
换相失败
high voltage direct current
single-phase grounding fault
commutation voltage offset
grounding impedance
commutation failure
