POWERNOKI直流输电技术全国重点实验室中国南方电网2023JINANStateKeyLaboratoryofHVDCCHINASOUTHERNPOWERGRID柔性直流输电在交直流混联电网中的应用与展望APPLICATIONANDPROSPECTOFVSC-HVDCINAC/DCHYBRIDPOWERGRID黄伟煌南方电网科学研究院WeihuangHUANGSEPRI-CSG2023年9月22日，济南22ndSept.,2023，JINAN春提纲CONTENTS柔性直流的技术特点TechnicalcharacteristicsofVSC-HVDC柔性直流的发展现状DevelopmentofVSC-HVDC川.柔性直流在大电网中发挥的作用RoleofVSC-HVDCinLargePowerGridsIV.柔性直流在新型电力系统的应用与展望ApplicationandProspectofVSC-HVDCinNewPowerSystems2柔性直流技术特点VsC-HVDCtechnicalcharacteristics柔性直流是采用全控型功率器件和模块化拓扑结构的新一代直流输电技术，可控性高、适应性好，可实现有功和无功独立解耦的全域运行。VSC-HVDCisanewgenerationofDctransmissiontechnologythatadoptsfully-controlledpowerdevicesandmodularizedtopology,withhighcontrollability,andcanrealizefourquadrantsoperationwithdecouplingcontrolofactiveandreactivepower.除了输电外，柔性直流能否部分取代交流系统元件的功能，例如“交流联络线模拟”“虚拟电磁环网”？“直流电厂”？这是本报告主要讨论的问题之Inadditiontotransmission,canVSC-HVDCpartiallyreplacethefunctionsofACsystemcomponents,suchas"Aclineemulation","Virtualelectromagneticloop","Dcpowerstation"?Thesearethemainquestionsthatwillbediscussedinthisreport.直流侧正极“箱革元A“箱量元B箱量元第二象限第一象限有功和无功独立解动率模块耦的全域运行母线功率模块功率模块功率模块quadrant2quadrant1桥臂功率模块模直流侧半桥子模块Half-bridgeModuleIndependentdecouplingofactiveandreactivepowerforfull-domainoperation直流侧负极鲜线柔性直流拓扑结构全桥子模块第三象限第四象限VSC-HVDCtopologyFull-bridgeModulequadrant3quadrant43提纲CONTENTS柔性直流的技术特点TechnicalcharacteristicsofVSC-HVDo柔性直流的发展现状DevelopmentofVSC-HVDC川I.柔性直流在大电网中发挥的作用RoleofVSC-HVDCinLargePowerGridsIV.柔性直流在新型电力系统的应用与展望ApplicationandProspectofVSC-HVDCinNewPowerSystems柔性直流技术发展现状DevelopmentofVSC-HVDC柔性直流技术已成为全球关注热点和发展趋势VSC-HVDCtechnologyhasbecomeaglobalconcernanddevelopmenttrend已运行的直流工程，传统直流占大多数、达到70%，柔性直流占21%LCCaccountsforthemajority(70%)oftheHVDCprojectsinoperation,andVSC-HVDCaccountsfor21%规划中的直流工程，柔性直流成为主流方案，规划数量是传统直流的2倍AmongplannedHVDCprojects,VSC-HVDChasbecomethemainstream,twiceofconventionalLCC3%86%16%1332%21%1925LETT39%ETT16%LTTLTTVSC84VSC54%MixtureUnknownMixture已运行直流工程数据来源：CIGREB4Unknown21HVDCprojectsinoperationDatasource:CIGREB443%00%规划建设中直流工程5HVDCprojectsunderplanningandconstruction柔性直流技术发展现状DevelopmentofVSC-HVDC柔性直流工程的电压和容量不断提高ThevoltageandcapacityofVSC-HVDCcontinuetoincrease.·中国虽然起步晚，但无论是从发展速度还是工程容量上，都呈赶超趋势AlthoughChinastartedlate,itiscatchingupbothintermsofdevelopmentspeedandengineeringcapacity800国外容量：1000MW=30Q0MW→5000MW乌东德中国直流电压5000MW600张北3000MW±800kvINEFLE鲁西↑400Transbaycable1000MW1000MW渝鄂NordLin200±500kV400MW41250MW1400MW01Crosssoundcable厦门±320kv330MW1000MWHellsjon南汇舟山多端10MW20MW南澳多端400MW1997中海油2010200MWTOMW2002201320162020年份6柔性直流技术发展现状DevelopmentofVsC-HVDC目前柔性直流在电网互联、远距离输电、新能源送出、中低压配电等四类主要场景得到了广泛应用Currently,VsC-HVDCiswidelyusedinfourmajorscenarios,includinggridinterconnection,long-distancepowertransmission,renewableenergytransmission,andpowerdistribution.回丰合电网互联AY新能源送出80%GridRenewableEnergyTransmissionInterconnection中国团柔性直流技术低交流微电网压g-distance远距离输电配直流微电网PowerTransmission网PowerDistribution德能柔性直流技术应用于电网互联VSC-HVDCTechnologyAppliedtoGridlnterconnection柔直应用于电网互联，实现两个电网电力交换，并提高已有交流电网安全稳定水平Vsc-HVDCforgridinterconnectionisappliedtoexchangepowerbetweentwogridsandimprovethesecurityandstabilityofexistingACgrids，电网互联可实现互供电力、互通有无、互为备用，可减少事故备用容量，增强抵御事故能力柔直不增加交流短路电流，不受交流系统短路容量限制，可快速灵活调节潮流，是电网互联的重要技术手段VSC-HVDCdoesnotincreasetheshort-circuitcurrentoftheACpowergrid,notlimitedbySCRoftheACsystem,canquicklyandflexiblyregulatethepowerflow,andisanimportanttechnicalsolutionforgridinterconnection国内外已建成的柔直背靠背联网工程分区2Completedback-to-backVSC-HVDCprojectsinChinaandabroad工程名称容量交流电压投入时间分区1分区3美国EaglePass工程36MW/±15.9kV132kV2000澳大利亚Murraylink工程220MW/±150kV132/220kV2002爱沙尼亚Estlink工程350MW/±150kV400/330kV2006柔直应用手交流电网互联英国Britain-500MW/±200kV400kV2013Ireland工程VSc-HVDCapplicationsforACgridinterconnections1000MW/±350kV500kV2016鲁西背靠背桑直工程1250MW/±420kV500kV2019渝鄂背靠背柔直工程1500MW/±400kV500kV2022中南通道柔直工程8柔性直流技术应用于电网互联VSC-HVDCTechnologyAppliedtoGridlnterconnection电网互联典型应用Typicalapplicationsforgridinterconnection鲁西背靠背柔直工程：首次将柔性直流用于西电东送主通道，实现电网分区柔性互联Luxiback-to-backvSC-HvDCproject:thefirsttimetouseVSC-HVDCforthemainchannelofwest-eastpowertransmission,realizingflexibleinterconnectionofasynchronouspowergrids.厂东电网背靠背直工程：应用于广东电网负荷中心，实现不同交流电网区域交流系统敌障的隔离，提供快速功率控制与紧急功率支撑，增加电网稳定性GuangdongBack-to-BackvsC-HvDCProject:AppliedintheloadcenterofGuangdong,itrealizestheisolationofACsystemfaultsindifferentACpowergridareas,providesfastpowercontrolandemergencypowersupport,andincreasesthestabilityofthepowergrid滇月罗平东雨变电站汪罗平背靠背云南百色广西鲁西背靠背桑直工程广东电网背靠背柔直工程Luxiback-to-backVSC-HVDCprojectGuangdongback-to-backVSC-HVDCproject9柔性直流技术应用于远距离输电VSC-HVDCTechnologyAppliedtoLongDistancePowerTransmission柔直运行控制，拓扑结构和核心器件的发展，促进了电压等级及输电距离的提升Developmentofcontrolstrategy,circuittopologyandpowerelectronicdeviceshavefacilitatedtheincreaseofvoltagelevelsandtransmissiondistances-双阀组串联拓扑与3000A等级器件研制，将柔直电压提升至±800kV，容量提升至5000MW-Dual-valveserialtopologyand3000A-rateddevicedevelopmenttoincreasevoltageto±800kVandcapacityto5000Mw加装直流断路器或“全桥+半桥”混合拓扑，可阻隔直流故障电流，实现远距离架空线故障的清除和快速重启-ByinstallingDCcircuitbreakersoradopting"fullbridge+halfbridge"hybridtopology,DCfaultcurrentcanbeblocked,realizingfaultclearingandfastrestartunderlong-distanceoverheadlinefaults.国内外已建成/建设中的柔直远距离架空线输电工程FBSMCompleted/underconstructionlong-distancetransmissionVSC-HVDCprojectsinChinaandabroad工程名称容量/电压输电距离直流故障清除投入时间纳米比交流断路器2010亚Caprivi300MW/-350kV970km清除时间1.5sLink工程HBSM张北直流3000MW/±500kV666km直流断路器20201452km2020昆柳龙直流5000MW/±800kV340km3ms开断电流全桥和半桥混合型MMC的结构示意图德国800MW/±320kV建设中全半桥，主动降压清除ULTRANET150ms电流过零全桥，主动降压清除Schematicstructureoffull-bridgeandhalf-bridgehybridMMCs10柔性直流技术应用于远距离输电VSC-HVDCTechnologyAppliedtoLongDistancePowerTransmission远距离输电典型应用Typicalapplicationsforlongdistancepowertransmission昆柳龙直流工程：落点广东的第10回直流输电工程，将乌东德电站（世界第7大水电）的电力输送至两广负荷中心，受端采取特高压柔性直流技术KunliulongProject:the1OthDCtransmissionprojectinGuangdong,transmittingpowerfromWDDStation(theworld's7thlargesthydropowerstation)totheloadcentersofGD&GXprovinces,withUHVVSC-HVDCtechnologyatthereceivingend世界上首次将柔性直流用于远距离、大容量、架空线输电-Theworld'sfirstapplicationofvsc-HvDcforlong-distance,high-capacity,overheadlinepowertransmission.CCTV1305km云南昆北换流站西柳北换流站广东龙门换流站乌东德水电站央视记者朱继华高森王戈李超云南台Udundehydroelectricpowerstation南方电网乌东德电站送电广东广西特高压工程投运昆柳龙直流工程示意图SchematicdiagramofKunliulongDCproject11柔性直流技术应用于新能源送出VSC-HVDCTechnologyAppliedtoRenewableEnergyTransmission海风大容量集中送出能有效降低单位开发成本，柔直是深远海风电送出的主流方案Large-capacitycentralizedtransmissionofoffshorewindcanreducetheunitdevelopmentcost,VsC-HVDCisthemainstreamsolutionofthedistantoffshorewindpowertransmission深远海风柔直送出，直流海缆无充电无功问题，输电距离远DistantoffshorewindVSC-HVDCtransmission;NoreactivepowerissuesforDCcables;Longdistancetransmission国外已建成的海上风电柔直工程主要集中在德国，直流电压等级以土320kV为主送出工程造价/亿元陆上站CompletedoverseaoffshorewindpowerVSC-HVDCprojectsaremainlylocatedinGermany,DCvoltagearemainly±32OkV.直流海缆国内外已建成的海上风电柔直送出工程海上站completedoffshorewindpowerVSC-HVDCtransmission下降projectsinChinaandabroad25%工程名称容量/电压输电距离投入时间BorWin1400MW/±150kV200km2010BorWin2800MW/±300kV200km2015DolWin1800MW/±320kV165km2015HelWin1576MW/±250kV130km2015HelWin2690MW/±320kV130km2015SylWin1864MW/±320kV205km2015DolWin2916MW/±320kV135km20172×1GW1×2GWDolWin3900MW/±320kV160km2017海风直流送出工程造价对比（国内）BorWin3900MW/±320kV200km20191100MW/±400kV108km2021CostcomparisonofVSC-HVDCtransmission如东海上柔直projectsforoffshorewindpowerplant(China)12柔性直流技术应用于新能源送出VSC-HVDCTechnologyAppliedtoRenewableEnergyTransmission新能源送出典型应用Typicalapplicationsofrenewableenergytransmission如东海风柔直工程：我国首个海风柔直送出工程，电压等级土400kV、容量1.1GW-RudongOffshoreWindVSC-HVDcProject:thefirstoffshorewindVSC-HVDCtransmissionprojectinChina,±40okV,1.1GW.，青州五/七柔直工程：采用±500kV/2GW柔直送出，预计2024年建成，将成为世界首个投产的2GW海上风电直流送出工程，也是世界容量最大的海风柔直工程QingzhouFive/SevenVSc-HVDcProject:Adopting+500kVi2GWVSC-HVDC,expectedtobecompletedin2024,willbecometheworld'sfirstcommissioned2GWoffshorewindpowerVSC-HVDCproject,alsotheworld'slargestoffshoreVSC-HVDC.大竹酬青洲七风电场青洲五风电场，1000MW1000MW如东海风柔直工程青州五/七桑直工程QingzhouFive/SevenVSc-HvDcProject13RudongoffshoreWindVSc-HVDcProject柔性直流技术应用于中低压配电VSC-HvDcTechnologyAppliedtoMedium/LowVoltagePowerDistribution柔直向配电和用电延伸，可改善配电网运行性能，提高供电质量，促进节能减排vsc-HvDCextendstopowerdistributionandconsumption,whichcanimprovetheperformanceofdistributiongridenhancethepowerquality,andpromoteenergyconservationandemissionreduction分布式光伏广泛接入、电动汽车负荷快速增长，现有配电网面临挑战Distributedphotovoltaicwidelyaccessed,rapidgrowthofelectricvehicleloads,theexistingdistributionnetworkfaceschallenges中低压直流配电应用场景丰富，如配电网柔性互联、配电线路增容改造、工业园区/楼宇直流供电MediumandlowvoltageDCpowerdistributionapplicationscenariosareabundant,suchasinterconnectionofdistributionnetworks,capacityenhancementofdistributionline,DCpowersupplyinindustrialbuildings国内外已建成的柔直配电工程BatteryEVsCompletedVsc-HVDCprojectsforpowerdistributioninChinaandabroad工程名称容量/电压拓扑结构投入时间PVPanePVPanelsFUN-LV（英国）240(400)两端/三端背靠背2016kVA/0.4kV(AC)dcdcNetworkEquilibriumFPL（英国）20MW/33kV(AC)两端/三端背靠背2018Gric7.6MW/±2.5kV三端直流配网2019FENResearchCampusMVDC（德国）30MW/±27kV两端柔直2020ApplianceElectronicsightingGridRectifierApplianceElectronicsLightingAngle-DC（英国）30MW/±10kV四端直流配网2018SystemEfficiency42MW/±10kV四端直流配网杭州大江东直流配网4MW/±10kV五端直流配网2018珠海唐家湾直流配网30MW/±10kV三端背靠背2018贵阳直流配网2019北京延庆交直流混合配网东莞交直流混合示范工程5.18MW/10kV多电压多层环网2020交流配电VS直流配电佛山多状态开关18MW/±10kV三端背靠背2021ACpowerdistributionvs.DCpowerdistribution14柔性直流技术应用于中低压配电VSC-HvDCTechnologyAppliedtoMedium/LowVoltagePowerDistribution中低压配电典型应用Typicalapplicationsformediumandlowpowerdistribution珠海唐家湾工程：多端多层级、可网络重构的土10kVI40MW柔直配电网，实现多个交流变电站的直流柔性互联和备用功率支撑，提高了系统供电可靠性ZhuhaiTangjiawanProject:Multi-terminal,multi-layer,networkreconfigurabledistributionnetwork,realizingDCflexibleinterconnectionofmultipleACsubstationsandstandbypowersupport,improvingsystempowersupplyreliability苏州同里工程：多电压等级、多应用场景的直流配电网，可实现各类直流电源、负荷和储能的友好互联、高效接入，满足用户高可靠供电、绿色用能和直流供电需求SuzhouTongliProject:Multi-voltagelevel,multi-applicationscenarioDCdistributionnetwork,whichcanrealizethefriendlyinterconnectionandefficientaccessofvarioustypesofDCpowersources,loadsandenergystorage,andmeettheusers'needsforhighlyreliablepowersupplygreenenergyuseandDCpowersupply鸡山站1直流微网鸡山站2唐家站珠海唐家湾柔直配电工程苏州同里柔直配电工程ZhuhaiTangjiawanflexiblepowerdistributionprojectSuzhouTongliflexiblepowerdistributionproject15提纲CONTENTS柔性直流的技术特点TechnicalcharacteristicsofVSC-HVDC柔性直流的发展现状DevelopmentofVSC-HVDC柔性直流在大电网中发挥的作用RoleofVSC-HVDCinLargePowerGridsIV.柔性直流在新型电力系统的应用与展望ApplicationandProspectofVSC-HVDCinNewPowerSystems16优化电网结构，提升电网本质安全水平OptimizingtheGridstructureandEnhancingGridSecurity鲁西背靠背柔性直流工程Luxiback-to-backVsC-HVDCproject云南电网超过70%功率由直流传输，直流故障后大规模潮流转移到交流通道，易造成同步失稳Morethan7o%ofthepoweroftheYunnanpowergridistransmittedbyVDC,andthelarge-scalepowertransfertotheACchannelafterDCfailurewileasilycausesynchronizationinstability.南网首次将柔直用干500kV主网架，建成鲁西直流，用于西电东送主通道，实现电网分区互联ChinaSouthernPowerGrid(CSG)firstlyusestheVSC-HVDCforthe5oOkVmaingrid,andbuildsLuxiB2BHVDCasthemainchannelofwesttoeasttransimmision,realizingtheinterconnectionofasynchronouspowergridsindifferentregions.柔直运行稳定可靠，年利用小时数超5000小时（2018年），交流故障下还能发无功支撑电网恢复VSC-HVDCoperationisstableandreliable,withannualutilizationhoursexceeding5,o00hours(2018),andreactivepowercanbegeneratedtosupportgridrecoveryunderACfaults西联播空网刚电压新/广西刚联宽网刚电压1/广西例联编空月刷电压系统功角失稳风险基本被消除多直流持续换相失败引起系统失稳风险得到缓解交流电压跌落至0.2p.u.提供400Mvar无功支撑交流系统恢复云南水电送出增加250-340万干瓦17优化电网结构，提升电网本质安全水平OptimizingtheGridstructureandEnhancingGridSecurity鲁西背靠背柔性直流工程主要创新点MaininnovationsofLuxiback-to-backVSC-HVDCproject首次提出多类型换流器的有功无功协调控制技术，实现了多换流器控制模式自动识别与功率互济Itisforthefirsttimetoproposethecoordinatedactive/reactivecontroltechnologyformultipletypesofconverters,realizingtheautomaticidentificationofmultipleconvertercontrolmodelsandpowerexchange.提出柔直暂停触发和快速恢复故障穿越控制技术，避免了交流故障下柔直停运，并提供动态支撑-TriggerblockingandfastfaultrecoverytechnologyareproposedtoavoidVsC-HVDCshutdownunderACfaultsandprovidedynamicpowersupport.首次提出了常直与柔直并联运行的控制保护系统架构ThecontrolandprotectionarchitectureforparalleloperationofLCC-andVSC-HVDCisfirstlyproposed无功功SCADA控制中心SCADAWASCADATr-shortTr-longTr-longTr-short合断路器分断路器200600柔性直流无功输出参考波（1EC60044-8）阀控VBCA阀控VBC常规直流滤波器投切阀2换流站1阀3换流站2换流站3无功功率协调控制TI有功P控制Udc控制有功P控制CoordinatedreactivepowercontrolUac控制Uac控制Uac控制个控制周期v/f控制百微秒级的暂停触发技术柔直控制基本架构18HundredsμstriggerblockingtechnologyBasicstructureofflexibleDCcontrol优化电网结构，提升电网本质安全水平OptimizingtheGridstructureandEnhancingGridSecurityLevel粤港澳大湾区中、南通道背靠背柔性直流工程Back-to-BackVSC-HVDCProjectsinGuangdong-HongKong-MacaoGreaterBayArea粤港澳大湾区负荷高度聚集，电网联系紧密，短路电流水平高，极端故障下存在大面积停电风险TheGuangdong-HongKong-MacaoGreaterBayAreahaslargeload,closelyconnectedgrid,highshort-circuitcurrentlevels,andfacestheriskofTarge-scalepoweroutagesintheeventofextremefaults.南网首次将柔直用于解决负荷中心电网安全稳定问题，工程投产前，粤港澳湾区电网全接线、全开机短路电流最大值67.6kA；工程投产后，短路电流降低14~25kAForthefirsttime,CsGhasusedVSc-HVDCforsolving.thesecurityandstabilityissuesoftheloadcenter.Beforethecommissionofproject,themaximumvalueofshort-circuitcurrentwas67.6kA.Afterthecommissionofproject,theshort-circuitcurrentwasreducedby14-25kA.化解了直流密集馈入运行风险，避免了负荷中心大面积停电，提高湾区电网电力供应和配置能力SolvetheriskofHVDCintensivefeed-inoperation,avoidlarge-scalepoweroutagesinloadcenters,andimprovethepowersupplyandallocationcapacityoftheBayAreapowergrid.3500同步机提供的电流下降20kA下降25kA西部分区东部分区柔直提供的电流下降15kA下降14kA故障期间同步机电源与柔直提供电流对比500干伏站点附近短路电流水平Short-circuitCurrentComparisonofSynchronous19ShortCircuitCurrentnear500kVStationratorsandvsc-HvDCsDuringFaults优化电网结构，提升电网本质安全水平OptimizingtheGridstructureandEnhancingGridSecurityLevel中、南通道背靠背柔性直流工程主要创新点MainlnnovationsofBack-to-BackVSC-HVDCProjectinGreaterBayArea首次提出了柔直阻抗重塑、柔直交流断面失电下的快速过电压抑制方法等技术，大幅提高了柔性直流与复杂电网暂稳态交互控制技术improvestheperformanceoftransient-andsteady-statesinteractionsbetweenVSC-HVDCandACgrids.常规FLC控制交流频率锁相+01000优化前低通滤波处理优化后500sHmmc+βma交流MMCA相交流电压/kV电压阀级控制虚拟同步控制无功功率或交Ere6.16.156.26.256.36.356.46.45控制五次谐波电流29A（投入前）LFL流电压控制Fifthharmoniccurrent29A(beforeoperation)优化前频率波动更小0.02Hz30106ms优化后2052.6ms15.06.156.26.256.36.356.46.456.5频率优化控制技术t/sFrequencyoptimizationcontroltechnology优化前后过压与避雷器耐受时间对比五次谐波电流12A（投入后）Comparisonofovervoltageandarrester20withstandtimebeforeandafteroptimizationFifthharmoniccurrent12A(afteropertion)降低多回直流同时换相失败的安全风险ReducingtheriskofCommutationFailureofmultipleHvDCs昆柳龙特高压柔性直流工程KunliulongVSC-UHVDCProject多回直流集中馈入的受端电网中，交直流相互影响问题突出，存在多回直流同时换相失败风险IntherecievingendofmultipleHvDCcentralizedfeeders,theissuescausedbyAC/DCinteractionsareobvious,andthereisariskofcommutationfailureofmultipleHVDCs.-南网首次提出特高压柔直向负荷中心送电的技术路线，为广东电网的安全稳定提供了保障CSGfirstlyproposedthetechnicalrouteofUltrahighVSC-HVDCpowertransmissiontoloadcenters,whichprovidedsecurityandstabilityfortheGuangdongpowergrid.受端采用柔直，扭转了系统稳定恶化的趋势，多回直流同时换相失败范围显著减小、风险大幅降低TheuseofVSC-HVDCatthereceivingendreversesthetrendofdeterioratingsystemstability,andtheriskofcommutationfailureissignificantlyreduced多3.41+LCC→VSC入2.502.39效2.69短2.52.12路比2010年（5回直流）2015年（8回直流）2018年（9回直流）2020年（10回直流）受端换流站采用柔直扭转了系统稳定恶化的趋势TheuseofvSc-HvDcatreceivingendreversesthedeteriorationofsystemstabilityRedarea:LCCfailures;yellowarea:VSCfailures21降低多回直流同时换相失败的安全风险ReducingtheriskofCommutationFailureofmultipleHvDCs昆柳龙直流工程主要创新点MaininnovationsofKunliulongproject首创了混合直流稳态及暂态运行控制技术，实现混合直流在各种工况下的全域稳定运行ThefirsthybridHVDCsteady-stateandtransientoperationcontroltechnology,realizingstableoperationundervariousoperatingconditions.，提出了特高压柔直阀组能量平衡、阀组在线投退等控制技术，满足柔直双阀组灵活转换及运行需求-energybalanceofVsC-HvDCvalvegroup,valvegroupon-lineswitchingin-out,tomeettheflexibleoperationrequirements-面向柔直远距离架空线故障清除国际难题，首创全半桥混合拓扑和主动反压架空线故障自清除方法Full-andhalf-bridgehybridcircuittopologyandactivenegative-voltagegenerationforthefaultclearingoflong-distanceoverheadlineareproposedUdc/p.u.直流电压发散！投入平衡控制主动降压IGBT脉冲控制方法一最小触发角控制直流模块11+△U电压控刷故障电流模块n定电流控制1.0故障B全桥低压限流定电压控制<1%0相相相定电流控制架空线模块1模块n低压达1Idc/p.u.半桥限流0.50.5IovscIolccQ/p.u.P/p.u.混合直流输电运行控制技术柔直特高压高低阀组串联运行通过降压实现架空线故障自清除HybridHVDCoperationtechnologyVSC-UHVDCvalveseriesmanifoldsSelf-clearanceofoverheadlinefaults23operatingthroughvoltagereduction提纲CONTENTS柔性直流的技术特点TechnicalcharacteristicsofVSC-HVDo柔性直流的发展现状DevelopmentofVSC-HVDC川I.柔性直流在大电网中发挥的作用RoleofVSC-HVDCinLargePowerGridsIV.柔性直流在新型电力系统的应用与展望ApplicationandProspectofVSC-HVDCinNewPowerSystems24新型电力系统面临挑战ChallengesoftheNewPowerSystems新型电力系统面临源侧强随机波动性和低转动惯量带来的多时间尺度功率平衡灵活调节问题，以及电力电子控制主导的新形态尚步、电压、频率和振荡稳定控制问题-Newpowersystemsfacetheissuesofmulti-timescalepowerbalanceandflexiblepowerregulationduetorandomnessofrenewableenergyanddecreaseofinertia,aswellasnewformsofsynchronization,voltage,frequency,andoscillationstabilizationdominatedbypowerelectroniccontrol多直流送受端电网部分时段直流、新能源等非同步机电源装机和出力占负荷比例将超过70%，其中直流是单体容量最大的灵活可控电源Theinstalledcapacityandoutputofnon-synchronous.powersourcessuchasHVDCandrenewableenergyresourceswillaccountformorethan7o%ofthe'loadinsomeperiods,amongwhichHVDCisthelargestflexibleandcontrollablepowersourceinthegrid新能源出力强随机波动性转动惯量低、频率波动大电力电子控制主导新稳定问题RandomnessandvolatilityofrenewableenergyLowinertiaandlargefrequencyfluctuationstabilityissuesdominatedbypowerelectroniccontrol200同步恒速同步恒速光伏出力波形50Hz50Hz2030广东省电力系统8760小时运行模拟同步发电机电力系统8.558.65传统电网逆变器低频振荡自然同步耦合非同步同步恒速变速50Hz新能源电网非同步发电电力系统非同步无耦合VSC大信号功角稳定25新型电力系统面临挑战ChallengesoftheNewPowerSystems为应对新型电力系统的可靠性、经济性、安全性和消纳挑战，直流必须从依附电网转变为主动支撑电网从“电能输送”单一核心职能发展为“输电+运行控制”双重职能，从事实上的容量主体转变为职能上的控制主体承担网络构建和系统运行关键责任-Inordertocopewiththechallengesofreliability,economy,securityandconsumptionofthenewpowersystems,HVDCmustchangeitstransmission+operationandcontrol",andfromacapacitysubjecttoafunctionalcontrolsubject,takingthekeyresponsibilitiesofnetworkconstructionandsystemoperation.藏东南清洁能源基地北方能源基地三广直流国啤真流50柔直附加惯量和一次调频控制后，提49.8供额外有功功率支撑，预计最大单条兴安直流直流闭锁时，主网初始频率变化率为普西骨常骨49.60.1Hz/s，频率最低点为49.4Hz，准幼东德直流49.2柔直控制方式：稳态频率为49.8Hz，满足主网频率稳！海西北南流49无惯量/调频控制定要求。云广直池48.8有惯量/调频控制柔直不加惯量和一次调频控制，预计预扎衰直流0最大单条直流闭锁时，主网初始频率102030405060变化率为0.4Hz/s，频率最低点为48.8Hz，准稳态频率为49.6Hz，不澜滑国家水电基地时间/s满足主网频率稳定要求。26柔性直流技术新应用NewApplicationsofVSC-HVDCTechnology1）柔直频率同步控制技术Vsc-HvDcfrequencysynchronizationcontroltechnology云南与主网异步解决了潮流转移导致的同步失稳问题，但云南电网水电比例较高，高频问题突出AsynchronybetweenYunnanandthemaingridsolvestheproblemofsynchronousinstabilitycausedbypowerflowtransfer,butthehighproportionofhydropowerinYunnanpowergridleadstotheover-frequencyissue需要通过系统稳定控制，直流FLC机组一次调频等频率控制措施，确保云南电网频率稳定NeedtoensurefrequencystabilityofYunnanpowergridthroughfrequencycontrolmeasuressuchassystemstabilizationcontrol,FLCandprimaryfrequencycontrol,etc.异步电网各自进行频率控制，失去频率同步性，无法实现全网调频资源的实时、自动共享Asynchronouspower.gridscarryoutfrequencycontrolindividually,losingfrequencysynchronizationandfailingtorealizereal-time,aufomaticsharingoffrequencyregulationresources52.552.0F高频保护高周切机自动发电控制AGC51.5控切机、切负荷51.0直流频率控制（FLC）50.5水电机组一次调频火电机组一次调频50.01000200030004000500060007000800050Hz±0.033±0.05±0.15+0.5+0.8+1.5f(Hz)与主网异步后，云南电网高频问题突出27Afterasynchronizationwiththemaingrid,over-frequencyissuebecomesobviousinYunnan'spowergrid柔性直流技术新应用NewApplicationsofVSC-HVDCTechnology柔直频率同步控制技术根据两侧电网频率的差值调节功率，实现异步电网频率同步VsC-HvDcfrequencysynchronizationcontroltechnologyadjuststhepoweraccordingtothedifferencebetweenthetwoasynchronousgridfrequenciestoachievefrequencysynchronizationoftwoasynchrousgrids频率同步控制已应用于鲁西柔直背靠背工程，投入后云南电网率和南网主网锁率趋向一致andcSGmaingridtendstobethesameaftertheenableofthiscontrolscheme.显著提升南方主网和云南调频资源的实时、自动共享能力，对构建异步电网统一的调频辅助服务市场有重大意义Significantlyimprovethereal-timeandautomaticsharingcapabilityofsourcesbetweenthemainandYunnanpowergird,whichisofgreat频率同步功能投入主网某电厂跳闸200MW50.022:35:00.00022:35:10.0022.35:20.00022.35.30.00022:35:40.00022:35:50.000:49.995■±网预率：X岸拆值2023:03/1022:35:18.780，Y星标值主网频率0745200000745:50.00007.45:10000柔直功率07.45:4.00022:35:00.00022:35:10.00022:35:30.00022:35:40.00022:35:20.000主网和云南频率均同步跌至最低49.96Hz250电厂跳闸后柔直功率瞬时提升约70MW广西云南两侧电网频率的现场调试录波22:35:00.00022:35:10.00022:35:20.00022:35:30.00022:35:40.0002235:50.00FieldRecordingofGridFrequenciesonBothSidesofGuangxiand鲁西频率同步功能试运行期间某电厂跳闸现场录波YunnanGridsLuxifrequencysynchronizationfunctionduringthetrialoperation28ofapowerstationtrippingsiterecording柔性直流技术新应用NewApplicationsofVSC-HVDCTechnology21嵌入交流电网的异同步控制技术EmbeddedVSC-HVDCAC-imitationcontroltechnology交流电网采用背靠背直流工程解网之后，交直流并列运行，交流线路的功率根据两侧相角差运行自动调节，直流则根据调度指令进行定功率运行VSC-HVDCembeddedinacgridformstheparalleloperationofACandDCsystems.ThepoweroftheAClineisautomaticallyadjustedaccordingtothephaseangledifferencebetweentwosides,andtheHVDCisoperatedataconstantpoweraccordingtothedispatchinstructions.当出现交流系统状态出现变化（切机、切负荷），现有控制下柔直不会根据系统的运行状态自动调整输送功率，无法快速实现双侧交流系统的功率互济WhenthereisachangeinthestateoftheACsystem(generatortripping,loadshedding),VSC-HVDCunderthetraditionalcontrolwillnotautomaticalyadjusttheoutputpoweraccordingtotheoperatingstateofthesystem,anditisimpossibletoquicklyrealizethepowerexchangeoftheACsystemonbothsides.UU电网2电网1XP.+jQ.有功功率基本保持不变交流线路潮流根据两侧相角差进行自动调节在传统控制模式下，系统状态变化时，柔直保持定功率运行AclinecurrentisautomaticallyadjustedaccordingtothephaseVSC-HVDCmaintainsconstantpoweroperationwhenthesystem29angledifferencebetweenthetwosidesstatechanges.柔性直流技术新应用2NewApplicationsofVSC-HVDCTechnology嵌入交流电网的异同步控制技术EmbeddedSc-HVDCAC-imitationcontroltechnology根据两侧电网电压相角幅值变化快速调节功率，模拟交流联络线，实现功率自动控制和互济Byquicklyadjustingpowerflowaccordingtothephaseanglechangeofbothsidesofthegrid,VSC-HVDCcanimitatetheAcline,andrealizeautomaticpowercontrolandpowerexchange.稳态运行时，柔直模拟固定阻抗交流联络线，两侧电网功率自动互济，两侧电网类似于同步运行Duringsteady-stateoperation,VsC-HVDCimitatesAClinewithfixedimpedance,thepoweronbothsidesofthegridisautomaticallyexchanged,whichissimilartosynchronousoperation一电网故障时，柔直隔离故障并抑制短路电流，降低两侧电网相互影响，两侧电网类似干异步运行Incaseofgridfault,VSC-HVDCisolatesthefaultandsuppressestheshort-circuitcurrent,reducestheinfluenceofthegridsinteraction,whichissimilartoasynchronousoperation-6U1Z81U22821100率/M异同步控制模式功-8U1z81U2262郁800柔性直流定有功模式PU,U2sin(S,-82)700-10X23t/s452.53t/s3.54柔直模拟阻抗X的交流联络线，有功功率参考值跟切除部分负荷或断开交流线路时，有功功率变化基相比传统定有功控制，柔直投入异同步控制，踪两侧电网电压幅值和相角差本一致，柔直可模拟阻抗X交流线路两侧相角差减小，实现功率互济PreftrackingofVdiffandodiffActivepowerarebasicallyconsistent,andvscReducingodifftoachievepower30HvDCcansimulateimpedanceXAClinesmutualassistance柔性直流技术新应用NewApplicationsofVSC-HVDCTechnology异同步控制技术已应用于粤港澳大湾区中、南通道柔直背靠背工程AC-imitationcontrolhasbeenappliedtotheGreaterBayAreaBack-to-BackVSC-HvDCProject-并列的清城-花都双线发生N-2故障并切除后，柔直快速调整功率，清城-花都双线部分功率部分自动转移到柔直，降低了龙门-木棉双线的线路载荷AftertheparallelQingcheng-HuadudoublelineexperiencedN-2.fault,VSC-HVDCquicklyadjustedthepower,andpartofthepowerofQingcheng-HuadudoublelinewasautomaticallytransferredtoVSC-HVDC,whichloweredthelineload'ofLongmen-Mumiandoubleline清城花都双线2000故障后龙门-木棉双线1500柔性直流系统传输通道故障前不投异同投入异同步柔性直流清城-花都双线500MW宠-朵棉双线000步控制控制交流系统1南南500500MW685MW双单元柔交流系统2柔直功率自动增加清城-花都双线550MWOMWOMW0直背靠背有功功率/MW500-1000-15000124龙门-木棉双线105MW740MW330MWt/s中通道柔直近区交流接线图清城-花都双线N-2故障投入与不投异同步控制功率变化对比MiddleChannelVSC-HVDCNearZoneAC投入异同步控制试验波形ComparisonofpowerchangebetweentheenableWiringDiagramanddisableofAC-imitationcontrolQingcheng-HuadudoublelineN-2failurewiththeenableofAC-imitationtestwaveform31柔性直流技术新应用3NewApplicationsofVSC-HVDCTechnology柔直潮流快速反转控制技术VSC-HvDCFastPowerReversalControlTechnology常直潮流反转需要反转电压极性，现有直流工程均未配置潮流快速反转功能PowerreversalofLCCrequiresreversalofvoltage,andexistingLCCprojectsarenotequippedwithfastpowerreversalcontrol在电力市场下，电网对灵活、平滑的潮流反转有较大需求，美柔直仅需将功率参考值下发由正值变为负值，即可实现在线潮流反转（电压极性不变，电流反向），无最小功率限制，可零功率运行Electricitymarkethasgreatdemandonflexibleandsmoothpowerreversal.VSC-HVDCcanrealizeonlinepowerreversalbysimplyoperation.西部分区东部分区MW南粤直流24小时96点功率曲线P/pu1pu佛圳1500功率反转10000江中未地区惠州北地区500t/s粤东地区肇地区香港85344381505058443332505058-1pu5008西地区时间-1000澳门-1500-2000广东东西电网桑直分区互联电力市场推进下，柔直功率反转将更加频繁柔直功率运行区间GuangdongEast-WestPowerGridVSC-VSC-HVDCpowerreversalstobecomemoreVSC-HVDCpoweroperatingrangeHVDCInterconnectionfrequentaspowermarketadvances32柔性直流技术新应用3NewApplicationsofVSC-HVDCTechnology柔直潮流快速反转控制技术VSc-HvDCFastPowerReversalControlTechnology满足紧急下广东东西电网快速功率互济：功率提升、回降、限制等稳控功能可调制至反向运行，稳控动作效果更好：柔直FLC调节可正反向反复暂态调节，频率稳定性调制效果更佳-ThisfunctioncanmeettherapidpowerexchangeofGuangdongGridunderemergencysituations:thestabilizedcontrolfunctionssuchasrun-up,run-back,powerlimitation,etc,canbechangedteverseoperationforbetterstabilizedcontrolactions;VSC-HVDCFLC功率回降功率回降FF3000MWP=1500MW3000MW1500MWOMW50Hz50HzP=3500MWOMW-500MW频率跌落量减少-3000MWAFLC调节可反向FLC调节最小到零回降后功率与初始功率回降后功率与初始功率OMW同方向可反方向OMW功率最大可调节量：功率最大可调节量：3000MW6000MW传统功率回降VS柔直功率回降FLC调节最小到零VSFLC调节可反向ConventionalPowerDropVSvSC-HVDCPowerDropFLCadjustmentminimizedtozeroVSFLCadjustmentreversible33柔性直流技术新应用NewApplicationsofVSC-HVDCTechnology4）柔直带区域孤网运行控制技术OperationandcontroltechnologyofVSC-HVDCwithregionalisolatednetwork-在交流线路检修、交流线路跳闸情况下，柔直被动进入“带地区孤网特殊运行方式-InthecaseofAClinemaintenanceortripping,VSC-HVDCentersthespecialoperationmodeof"isolatednetwork”-根据孤网系统强度，柔直具备区域孤网快速调频控制能力，并作为孤网最大电压源提供电压支撑-Accordingtothestrengthofisolatednetwork,VSC-HVDChastheabilitytoachievefastfrequencycontroloftheregionalisolatednetworkandprovidevoltagesupportasthelargestvoltagesourceinisolatednetwork同塔双回线线路检修柔直运行控制需求：路故障VSC-HVDCoperationrequirements:适应交流系统宽短路比柔直换流站柔直跟网/构网自适应切换控制，区域孤网Adaptiveswitching.betweengrid-followingandgrid-formingcontrol,adaptingtowideshort-circuitratioofACsystem.柔直快速频率调节能力Fastfrequencycontrol柔直交流电压快速稳定能力Fastvoltagestabilizationcapability南粤换流站线路检修+故障，被动进入区域孤网运行方式South-Guangdongconverterstationlinemaintenance+fault,passiveintotheregionalisolatednetworkoperationmode34柔性直流技术新应用5NewApplicationsofVSC-HVDCTechnology支撑大规模新能源基地外送控制技术ControltechnoiogyofVSC-HVDCforiarge-scalerenewableenergytransmission在某些场景下，存在风火打捆、水光打捆外送需求，柔直采用带惯量与阻尼的构网型控制技术，在系统遭受大扰动时，可降低传统发电机与柔直构造电网重新同步过程中功率超调量与波动时间Insomescenarios,therearetherequirementsforthetramsmissionofwind-thermalandhydropower-PVgenerations,VSC-HVDCadoptsthegrid-formingcontrolwiththeinertiaanddamping,whichcanreducethepowerovershootingandfluctuationtimeduringtheresynchronizationprocesswhenthesystemissubjectedtoalargedisturbance.发电机调整出力发电机转速AA24.:Gr8chsNZDO1_WmAA24:GraphsAdjustmentofgeneratoroutput稳定时间8s10稳定时间6s水轮机出力交流系统三相故障功率低至500MW低至1000MWThree-phasefaultsinACMW定U/F控制systems80803U/Fcontrol交流电压构网型控制35Gridformingcontrol柔性直流技术展望电网惯量低ProspectsofVSC-HVDCTechnology1提升电网惯性水平的构网型控制技术Grid-formingtechnologytoenhancethegridinertia预计2060年我国新能源发电占比将由当前13%提升至超过60%，系统双高特性凸显，日Itisexpectedthat,in2060,China'srenewableenergygenerationratiowillbeincreasedfrom13%tomorethan60%,leadingtohigh到2035年，南方电网主网惯量常数将降至2s以下TheinertiaconstantofChinaSouthernPowerGridmainwilldropbelow2sby2035到2030年，云南电网惯量常数将降至2s以下TheinertiaconstantofYunnanpowergridwilldropbelow2sby2030超过60%0.7中0.7新能源占比/%（左坐标）100%%6新能源占比/%（左坐标）惯性常数/s（右坐标）8%5%21%惯性常数/s（右坐标）313%8%0.63.50.63.5380%33%35%2.51.54930.58%0.50.536-7%0.42.50.460%7%17%17%0.340%20%52%2%H-2si0.380%2040年8%0.2H=2s72%核电10%0.1年份7%11%202020252030203520402045205020601.50.2云南电网惯量预估7%年份0.1YunnanGridInertiaEstimate31%南方电网主网惯量预估22%ChinaSouthernPowerGrid0.5MainGridInertiaEstimate2025年2030年2050年2060年化石能源水电氢能风电光伏柔性直流技术展望ProspectsofVSC-HVDCTechnology1提升电网惯性水平的构网型控制技术Grid-formingtechnologytoenhancethegridinertia柔直通过构网型控制技术，在扰动工况下柔直可模拟同步发电机特性，提供惯量支撑功率VsC-HVDCcanemulatesynchronousgeneratorcharacteristicsandprovideinertiasupportunderdisturbancesbymeansofgrid-formingcontroltechnique.率变化率-VSC-HVDCneedtoreservepowerforinertiasupport,whichcancomefromtheACsystemattheotherend,themaximuminertiaconstantdependsonthepowerreservaitonandRoCoF.模拟的120发电机容量模拟的100dt柔直惯性常数交流侧惯量P(t=2H频率变化率80支撑功率60P<2500MW频率变化率（df/dt）越大，柔直提供的最大惯性常数越小40P=3500MWP-4500MWThelargerdf/dt,thesmallerthemaximuminertiaconstant最大惯性常数H(s)运行功率越小，柔直提供的最大惯性常数越大；20Thesmallertheoperatingpower,thelargerthemaximuminertiaconstant0运行功率小于柔直额定容量的一半时，受限于下调的功率裕度，柔直的最大惯0.20.40.60.81性常数基本不变。频率变化率(Hz/s)Whentheoperatingpowerislessthanhalfoftheratedcapacity,themaximum5000MW柔直站在不同运行功率下的惯量常数inertiaconstantisbasicallyunchangedduetothedownwardpowermargin.Inertiaconstantsof500oMWVSC-HVDCstation37atdifferentoperatingpowers柔性直流技术展望ProspectsofVSC-HVDCTechnology2）新型直流电厂技术NoveTBCstationtechnology直流换流站将取代传统电厂，成为受端电网主力电源到2060年直流规模预计增加6倍，直ThescaleofHVDCisexpectedtoincreasesixtimesby2060,withDcconverterstationsreplacingconventionalpowerstationsasthemainsourceinthereceivinggrid需充分挖掘直流的潜能，更好适应未来电网低短路比、低惯量等需求ThepotentialofHVDCneedstobefullyexploitedtobetteradapttofutureneedsofthegrid,suchaslowshort-circuitratioandlowinertia直流系统将由“输电通道”的单一功能向“直流电厂”多功能角色转变-HVDCsystemwillchangefromthesinglefunctionof"transmissionchannel"tothemulti-functionalroleof"DCpowerstation"输电通道（单一功能）直流电厂（多功能）水电储能光伏电网互联主动参与构建电网HVDCHVDC主动参与构网HVDCHVDC紧急功率支撑远距离输电主动控制稳定电网惯量支撑HVDCHVDC新能源并网具备能量自平衡柔性直流技术谐振抑制、谐波治理HVDC风电氢能能量自平衡38柔性直流技术展望ProspectsofVSC-HVDCTechnology3）多直流协同控制技术CoordinatedcontrolofmultipleVSC-HVDCs直流成为占主导地位的跨区可控互联设备群，通过多直流协同的运行控制策略设计和广域协同控制系统构建准紧急率支援-HvDChasbecomethedominantcross-areacontrollableinterconnectionequipmentgroups,andthroughthedesignofcoordinatedcontrolofmultipleHVDCsandtheconstructionofwide-areacoordinatedcontrolsystem,itrealizesthesharingofTarge-scalerenewableenergytransmissionchannels,thecross-areamutualaidofmulti-areapowerresources,aswellastheaccurateandemergencypowersupportunderthelargedisturbances.通过跨区支援，替代受端区域部分性价比较差的储能，切机命令提升回降中南提升\回降直流冏降中南通道）交流线路信息通道功率功率中南通道12000/并与受端性价比较优的储能一起应对负荷尖峰10000切机执行站清蓄惠蓄8000交主流站五昆振兴龙门博罗渡水4000（粤港澳大湾区）交直流协调控制主站本期：中南通道协调2000远期：多直流协调912133374145时间/h中通道单元南通道单元穗东东方常规火电深调火电跨区支援一负荷直流站1和21和2多直流跨区支援实现优化调峰大湾区交直流协调稳控系统Multi-dccross-areasupportforoptimalpeakshiftingGreaterBayAreaAC/DCCoordinationandStabilizationSystem39柔性直流技术展望ProspectsofVSC-HVDCTechnology4嵌入式柔直虚拟电磁环网技术EmbeddedVSC-HVDcVirtualElectromagneticLoopTechnology传统500/220kV交流电磁环网：提高供电可靠性，避免故障下主变过载损失负荷，严重故障下地区电网与主网解列运行：但会带来短路电流超标、电网结构负载调控难、220kV交流线路过载甚至失稳；Traditional5oo/220kVAcelectromagneticloopnetwork:improvethereliabilityofpowersupply,avoidthelossofloadunderfaults,.However,itwillcausetheexcessiveofshort-circuitcurrent,difficulttoregulatethegridstructureload,andoverloadingofAcline;外部等值500kV交流联络外部等值外部等值外部等值电源无功环流电源电源电源本地电源多本地电源少负荷多日U.eU,0,昌本地电源220kV交流联络本地电源本地电源本地电源供电区域A供电区域B供电区域A供电区域B500/220kV交流电磁环网：500/220kV柔直虚拟电磁环网：500kV/220kV输电能力以及阻抗不匹配选取片区能代表源、荷分布特性的关键站点相角500/220kVACelectromagneticringnetworks:500kV/220kVtransmissioncapacityandimpedancemismatch500/220kVVSC-HVDCVirtualEMRingNetwork:40Selectionofkeystationphaseanglesinaslicerepresentativeofsourceandloaddistributioncharacteristics柔性直流技术展望ProspectsofVSC-HVDCTechnology43嵌入式柔直虚拟电磁环网技术EmbeddedvSc-HVDcVirtualElectromagneticLoopTechnology500/220kV柔直虚拟电磁环网：在实现电磁环网的同时，可模拟220kV交流线路功率自动互济的优点，根据柔真两侧供电片区相角差值、模拟线路阻抗主动调整功率控制技术，实现两个片区共享本地电源、源荷分布更加均衡5oo/22okvvsC-HvDCvirtualelectromagneticloopnetwork:Withtherealizationoftheelectromagneticloopnetwork,itcanemulatetheadvantagesofautomaticpowerexchangeby22OkVAclineAccordingtothedifferenceofphaseanglebetweenthetwosidesofpowersupplyareas,theVSC-HVDCcansimulatethelineimpedancetoactivelyadjustthepower,sothetwoareassharethelocalpowersupply,andachievethemorebalanceddistributionofsourceandload.500kV交流联络外部等值外部等值外部等值外部等值电源电源电源电源本地电源多无功环流本地电源少、负荷多X日U.eU,0,本地电源220kV交流联络本地电源供电区域B本地电源本地电源供电区域A供电区域B供电区域A500/220kV交流电磁环网：500/220kV柔直虚拟电磁环网：500kV/220kV输电能力以及阻抗不匹配选取片区能代表源、荷分布特性的关键站点相角500/220kVACelectromagneticloopnetworks:500kV/220kVtransmissioncapacityandimpedancemismatch500/220kVVSC-HVDCVirtualEMloopNetwork:41SelectionofkeystationphaseanglesinaslicerepresentativeofsourceandloaddistributioncharacteristicsPOWERON直流输电技术全国重点实验室丰中国南方电网2023JINANStateKeyLaboratoryofHVDCCHINASOUTHERNPOWERGRID谢谢！Thankyou!huangweihuang@csg.cn春42