电力系统谐波成因分析及谐波潮流计算外文翻译Word下载.doc
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sandtechnology'
sunceasingdevelopment,thehighefficiencytradedtheclassequipmentandthemodulatoruse,highintheelectricalpowersystempressesthenonlinearelementwhichthedirectcurrenttransmissiontheapplication,themassivemisalignmentload'
sappearanceaswellasthepowersupplysystemitselfexistedandsoontocauseinthesystem'
svoltagewaveformdistortiontobegettingmoreandmoreserious,hascausedtheverybigharmtotheelectricalpowersystem,forexample:
Causesinthepowersupplysystemtheparttoloseincreases,reducescurrentcollector'
sservicelife,todisturbthecommunicationsystemandsoon.Seriouswhenevencanalsocauseequipmentthedamage,automaticcontrolmalfunction,relayprotectionmisoperation,thuscreatesthepowercutaccidentandsoonandotherquestions.So-called"
thefriendknowsother,isundefeatedinmanybattles"
therefore,mustrealizetotheelectricalnetworkovertonecomprehensiveprogramofpublicorder,mustmakecleartheovertoneoriginandtheelectricalnetworkinundertheeachdifferentmovementwaytheovertonetidalcurrentdistributedsituation,adoptsthecorrespondingmeasurelimitandtheharmoniccancellation,thuschangesthefriendlypowersupplysystempowersupplyqualityandguaranteessystem'
ssecurityeconomymovement.
Second,electricalpowersystemovertone'
soriginintheelectricalpowersystemtheovertonesourceismanyandvaried.Mainlyhasthefollowingseveralkinds:
in1,system'
seachkindofmisalignmentcurrentcollectorforexample:
Tradestheclassequipment,themodulator,theelectrificationrailroad,thearcfurnace,fluorescencethelamp,thedomesticelectricappliancesaswellaseachkindofelectronicenergyconservationcontroldeviceandsoonistheelectricalpowersystemovertoneimportantsource.Eveniftheseequipmentsuppliesitsidealsinewavevoltage,itusestheelectriccurrentisalsonon-linear,namelyhastheharmoniccurrentexistence.Andthesetheequipmentproducestheharmoniccurrentwillalsopourintotheelectricalpowersystem,willcausesystemeachplacevoltagetohavetheharmoniccomponent.Theseequipment'
sharmonythewavecontentdecidedthatinitscharacteristicandtheworkingcondition,basicallyhasnothingtodowiththeelectricalpowersystemparameter,mayregardasovertoneconstantflowthesource.2,thepowersupplysystemitselfexiststhenonlinearelementisovertoneanotherorigin.Thesenonlinearelementmainlyhasthetransformertostirupthecapacitorwhich,thereactorgroupthemagnetismleg,thealternatinganddirectconvertorstation'
ssilicon-controlledrectifiercontrollingelement,thesilicon-controlledrectifiercontrolandsoon.
3rd,likethefluorescentlamp,thedomesticelectricappliancesandsoonsinglecapacityisnotbig,butquantityandspreadsverygreatlyineachplace,electricpowerdepartmentwithdifficultymanagementcurrentcollector.Iftheseequipment'
scurrentharmonicscontentisoversized,willthenhavetheseriousinfluencetotheelectricalpowersystem,tothiskindofequipment'
scurrentharmonicscontent,whenmanufacturenamelyshouldlimitincertainquantityscope.4,thegeneratorsendoutovertoneelectricpotential.Thegeneratorwillsendouttheovertoneelectricpotentialatthesametimealsotohavetheovertoneelectricpotentialproduction,itsovertoneelectricitythepotentialwillbedecidedbygenerator'
sstructureandtheworkingcondition,basicallywillhavenothingtodowiththeexternalconnectionimpedance.Thereforemayregardasovertoneconstantpressuresource,butitsvalueisverysmall.
thethree,electricalpowersystemovertonetidalcurrentcalculatestheso-calledelectricalpowersystemovertonetidalcurrentcomputation,isthroughsolutionnetworkequationIn=YnUn(n=3,5,7......n:
Agreeswavenumberthenumber.Inistheovertonesourceloadpoursintoelectricalnetwork'
snsubharmonicelectriccurrentrowvector.Yniselectricalnetwork'
snsubharmonicconductance.Unisintheelectricalnetworkavariousnodesbusbarnsubharmonicvoltagerowvector).Obtainsintheelectricalnetworkvariousnodes(busbar)theharmonicvoltage,enterstoobtaininvariouslegs'
harmoniccurrent.
Whenintheelectricalpowersystemtheexistencehastheovertonesource,thistimeinthesystemthecontactvoltageandthebranchcurrentwillhavethehigherharmonic.Forthedeterminationharmonicvoltageandharmoniccurrent'
sinpowersupplysystemdistribution,neededtocarryontotheovertoneimpedanceconstitutionequivalentcircuitthetidalcurrent