简介:Inviewofthelimitationsinthepredictionofpollutionflashovervoltagebyleastsquaresregression,amethodtopredictpollutionflashovervoltagebyrobustregressionisproposed.Accordingtotestingvoltageandthedataofsaltdepositdensity(ρSDD)andnon-solubledepositdensity(ρNSDD),theregressioncoefficientissolvedbyacomplexweightingleastsquareiterationalgorithm.Initerativecalculations,theweightfunctionisadopted,inwhichtheweightcoefficientisthefunctionoftheresidualerroroflastiterationtoweakentheinfluenceofsingularvaluesontheregressioncoefficient.ThecharacteristicexponentdenotingρSDDinfluenceandcharacteristicexponentdenotingρNSDDinfluencearemappedbytheregressioncoefficient,andthusthepollutionflashovervoltageofinsulatorscanbepredicted.Throughthecomparisonoftestresults,robustregressionresultsandleastsquaresregressionresults,theeffectivenessoftheproposedrobustregression-basedforecastingmethodisverified.
简介:Accuratepredictionofwindpowerissignificantforpowersystemdispatchingaswellassafeandstableoperation.BymeansofBPneuralnetwork,radialbasisfunctionneuralnetworkandsupportvectormachine,anewcombinedmethodofwindpowerpredictionbasedoncooperativegametheoryisproposed.Inthemethod,everysingleforecastingmodelisregardedasamemberofthecooperativegames,andthesumofsquareerrorofcombinationforecastingistakenastheresultofcooperation.TheresultisdividedamongthemembersaccordingtoShapleyvalues,andthenweightsofcombinationforecastingcanbeobtained.Applicationresultsinanactualwindfarmshowthattheproposedmethodcaneffectivelyimprovepredictionprecision.
简介:ThispaperintroducesaMonteCarloscenariogenerationmethodbasedoncopulatheoryforthestochasticoptimalpowerflow(STOPF)problemwithwindpower.Byusingcopulatheory,thescenariosaresimulatedfrommultivariablejointdistributionbutonlyfromtheirdependencymatrix.Hence,thescenariosgeneratedbyproposedmethodcancontainfullstatisticalinformationofmultivariate.Here,thedetailsofsimulatingscenariosformulti-wind-farmareexplainedwithfoursteps:determinemarginofonewindfarm,fitthecopulas,chooseoptimalcopulasandsimulatescenariosbyMoteCarlo.Moreover,theproducingprocessofscenariosisdemonstratedbytwoadjacentactualwindfarmsinChina.Withthescenarios,theSTOPFisconvertedintothesameamountdeterministicsubOPFmodelswhichcanbesolvedbyavailabletechnologyperfectly.Resultsusingcopulatheoryarecomparedagainstresultsfromhistorysamplesbasedontwodesigns:IEEE30-busandIEEE118-bussystems.Thecomparisonresultsprovetheaccuracyoftheproposedmethodology.
简介:Energy-conservationbasedgenerationdispatchingistherevolutionarychangeinoperationmodewhichcouldreduceenergyconsumptionandpollutantemissions,promotepowerindustryrestructuring,andachievesustainabledevelopment.Socialbenefitevaluationoftheenergy-conservationbasedgenerationdispatchingunderthenewsituationandenvironmenthascomeintobeingasanimportanttheoreticalissue.Anewscenarioanalysisbasedsocialbenefitevaluatingmethod,whichisimplementedbycomparingtheenergyconsumptionandpollutantemissionsofdifferentscenariosdefinedbythekeyindicators,i.e.,loadfactorandcoalconsumptionstructure,isproposedinthepaper.Thenthecompositionofsocialbenefitisanalyzedfromthepointofthedispatchingmodeandthecoalconsumptionstructure.Themethodproposedisofclearphysicalmeaning.Itisnotonlypractical,butalsoapplicablefortheimplementationofenergy-conservationbasedgenerationdispatchingindifferentphasesandwithdifferentgoals.