电力系统及其自动化学报ProceedingsoftheCSU-EPSA第35卷第6期2023年6月Vol.35No.6Jun.2023计及交直流耦合作用的并网VSC小扰动稳定性分析朱克平1,何英静1,但扬清1,李倩2,曹建春2,宗皓翔2(1.国网浙江省电力有限公司经济技术研究院,杭州310008;2.中电普瑞电力工程有限公司,北京102200)摘要:针对忽略交直流耦合动态而造成并网电压源换流器小扰动稳定分析失准的问题,本文具体分析了交直流耦合作用对其稳定性的影响。首先,建立了电压源换流器交直流阻抗模型,并给出扫频测量方法验证了其准确性;然后,构建了电压源换流器交直流并网系统的广义源荷模型,利用广义奈氏判据对其进行稳定性评估;最后,具体分析了传统交流阻抗与所提交直流阻抗的判稳区别,以及直流侧动态、无功功率传输对于系统稳定边界的影响。所得结果表明了计及交直流耦合特性对于电压源换流器并网稳定边界准确刻画的必要性。关键词:并网电压源换流器;交直流;阻抗;小扰动稳定性;奈氏判据;扫频中图分类号:TM712文献标志码:A文章编号:1003-8930(2023)06-0106-10DOI:10.19635/j.cnki.csu-epsa.001087Small-signalStabilityAnalysisofGrid-tiedVSCConsideringAC/DCCouplingsZHUKeping1,HEYingjing1,DANYangqing1,LIQian2,CAOJianchun2,ZONGHaoxiang2(1.EconomicandTechnologicalResearchInstitute,StateGridZhejiangElectricPowerCo.,Ltd,Hangzhou310008,China;2.ChinaEPRIScience&TechnologyCo.,Ltd,Beijing102200,China)Abstract:Aimedattheproblemofinaccuratesmall-signalstabilityanalysisduetotheignoranceofAC/DCcouplings,theeffectofAC/DCcouplingsonthesystemstabilityisanalyzedindetailinthispaper.First,anAC/DCportimped⁃ancemodelofvoltagesourceconverter(VSC)isbuilt,anditsaccuracyisvalidatedbythefrequencyscanningmeasure⁃mentmethod.Second,thegeneralizedsource-loadmodelforanAC/DCgrid-tiedVSCsystemisestablished,anditssta⁃bilityisassessedbythegeneralizedNyquistcriterion.Finally,threeaspectsarestudied,includingthedifferencebe⁃tweenthetraditionalACimpedance-basedstabilityjudgementandtheproposedAC/DCimpedance-basedstabilityjudgement,aswellastheeffectsofDC-sidedynamicsandreactivepowertransmissiononthesystemstabilitymargin.ResultsindicatethatitisnecessarytoconsiderAC/DCcoupli...