西班牙葡萄牙大停电事故分析及启示

国家电网有限公司国家电力调度控制中心 Rui GeState Grid Corporation of ChinaNationut ElectriePowerDispatching-and ControlCen2025年8月 Content Basicinformation oftheincident AnalysisofCauses EnlightenmentandRecommendation I.Basicinformationoftheincident (1)IncidentOverview OnApril28,2025,anationwideblackoutoccurredinthepower grids of Spain and Portugal. Except for off-grid islandswith independent powersupply,almost all otherregions ofthetwocountrieswereaffected,impactingmorethan50million peopleand causinga total load loss of approximately30Gw.Criticalsectorssuchastransportation,communications,and healthcare were disrupted,and Spaindeclareda stateof nationalemergency. By00:22and04:00onApril29,all substationshadbeenfully restored. I.Basicinformationoftheincident (2)IncidentProcess BeforeApril28,thetotal generationoutput inSpainand Portugal was32.19and 5.06GW, respectivelywith new energyoutputaccountingfor71%and 70%.Thevoltageat 40okVkeygridnodeswasgenerallyhigh. Beforetheincident,only11conventionalgeneratingunits(7thermaland4nuclear)wereconnectedtothegrid-theminimumoperationlevelofconventional unitssofarthisyear. I.Basic informationof theincident (2)IncidentProcess SystemOscillationphase:At12:03and12:19,low-frequencyoscillations (0.6Hzand0.2Hz)occurred inthepowergrids. Somemeasures-suchasputtingseven4ookVlinesintooperationandreducingthepowertransmittedfromSpaintoFranceby1.3GW-suppressedoscillations. However, these measures led to reduced line power flow, aggravated reactive power surplus,andincreased system voltage. I.Basicinformationoftheincident (2)IncidentProcess DisconnectionPhase:12:32:57-12:33:18,2.2GW of new energyinsouthernSpain disconnected fromthegridduetoovervoltage, causingfrequencydropandvoltage surge. Islanding&CollapsePhase:12:33:18-12:33:30,thescaleofnewenergybeingdisconnectedfromthegrid due to overvoltage further expanded to 20 million kw. Spain-Portugal grid desynchronizedfrom the main Europeangrid.Underfrequencypumptripping andall six load shedding were activated while failing to halt collapse. I.Basicinformationoftheincident 3)Post-incidentRestorationProcess Spainrestoredpowersupplyviahydroblack-startandpowersupportfromFranceandMorocco. AT04:00,allsubstationsresumedpowersupply,with16hours. Portugalachievedrestoration of4subsystems throughthe black start of hydro and gas-fired unitsAT00:22,allsubstations resumedpowersupply,with12hours. Content Basicinformationoftheincident AnalysisofCauses EnlightenmentandRecommendation Il.AnalysisofCauses •On May9, ENTSO-E established an investigation team and publisheda summary of the blackout incident and therestoration situation.The investigation teamplans to submit apreliminaryreport in October and a formal report inApril 2026. :On June17,the Spanishgovernment submitted a report to Congress.The report wasapprovedby theNationalSecurity Council and compiled by the"4.28"Power Crisis Analysis Committee. On June18, Red Electrica de Espania (REE)released an analysisreport, analyzing thecauses and process fromtheperspective of the power grid operator. •The two reports are basically consistent in their descriptions of the process and analysis of the causes of the blackout.However, intermsofdeterminingresponsibilityfortheblackout,thegovernmentreportbelievesthatRedElectricadeEspana(REE)mademistakesinaspectssuchastheformulationofstartupplansandvoltagecontrol.Incontrast,thepowergridcompany'sreportarguesthatthekeycausesoftheblackoutweresystemoscillationstriggered by PV and the inability of conventional units to provide reactive voltage support as anticipated. *OnJune19,ENTSO-Eannouncedtheexpertinvestigationteamwouldcarefullyreviewtworeportsasan importantreferenceforthefinalinvestigationreport. Accordingtoinformation,theblackoutwasostensiblyacoincidencecausedbyacombinationoffactors suchas low-frequency oscillation, voltage rise,and thedisconnectionof newenergy However, it was actually the inevitable result of the long-term weakening of the security and stabilityfoundation of thepowersystem,exposing numerousproblems suchas stabilityfoundations,source-gridcoordination,faultdefenselines,andinstitutionalmechanisms. Il.AnalysisofCauses (1)WeakPowerGridStabilityFoundationandLong-UnresolvedPlanningLagIssues In recent years, the rapid development of new energy in Spain-Portugal grid has led to an installedcapacityexceeding75GW,resulting inasevereshortageofsystemregulationandsupportcapabilities. The connection between the Spain-Portugal grid and the main European grid is weak. Multiple low-frequencyoscillationeventshaveoccurred,buttheconnectionhasyettobeeffectivelystrengthened. Thematerialfoundation for ensuring secure and stable operation is severely deficient,and the systemoperationhasapproachedacriticalinstabilitythreshold.Thisistheessentialcauseofthesubsequentchainreactionsandthefinallarge-scaleblackout. Il.AnalysisofCauses (1)WeakPowerGridStabilityFoundationandLong-UnresolvedPlanningLagIssues First, the insufficient number of conventional units