特高壓輸電線路甩負(fù)荷引起發(fā)電機(jī)自勵(lì)磁及操作過(guò)電壓疊加的研究

1、天津大學(xué)碩士學(xué)位論文特高壓輸電線路甩負(fù)荷引起發(fā)電機(jī)自勵(lì)磁及操作過(guò)電壓疊加的研究姓名：徐陸宇申請(qǐng)學(xué)位級(jí)別：碩士專(zhuān)業(yè)：電力系統(tǒng)及其自動(dòng)化指導(dǎo)教師：張艷霞；薛士敏；賀家李201112ABSTRACTForalongpeoridoftime，alongwiththefasteconomicdevelopmentofourcountrytheelectricpowerdemandsincreasedrapidlyInthisSituation，t

2、heconstructionofUltraHighVoltage(uHV)transmissionpowersystemhasbecomeinevitableUHVtransmissionlinewiththeCapabilityof1ongdistancepowertransmission，1argetransmissioncapacitythesmallenergylossandthesmallinvestmentontherigh

3、tofwayetc，hasahugeeconomicbenefitsButthereisseriousovervoltageprobleminUHVsystem，whichhasbeenanimportantissueofUHVsystemdesignItaffectsnotonlytheinsulationofpowerequipment，butalSOdirectlyrelatedtothesafetyandreliabilityo

4、fUHVpowersystemAtpresentmanydeepresearcheshasbeendoneaboutthevariouskindsofovervoltageandtheirPeculiarities，andvariouseffectiveSuppressionmeasul‘a(chǎn)shasbeenproposed，WhichacquiredgoodresultsHowevertheresearchonthesuperposit

5、ionofswitchingovervoltageandselfexcitionovervoltagecausedbyloadrejectionintheUHVsystemofgeneratorwithlongtransmission1inecanbehardlyfoundinliteratureDuetothecomplexmodelofgeneratoranditstranscientprocess，inUHVtransmissio

6、nsystem，selfexcitationmayOCcurWhengeneratoroperatingwithlongtramsmissionlineAtthesametime，switchingovervoltagemayoccurwithloadrejectionThesuperpositionofthesetwoovervoltagescanbeSOseriousforthesafetyofpowersystemoperatio

7、nandmustbepreventedTherefore，thestudyofthesuperpositionovervoitagehasveryimportantsignificanceInthisthesisthesourceofselfexcitationandtheprocessofitsdevelopmentaredeeplystudiedandelaboratedandthenprovedbydigimlsimulation

8、firstBasedonthe匆0generatorequationandthehighprecisetenorderchaincircuittransmissionlinemodel，theindividualswitchingovervoltageandthesuperpositionofswitchingovervoltageandselfexcitationovervoltagebysuddenloadrejectionofth

9、eUHVlongdistancetransmissionlineisanalyzedandsimulatedThecomparisonshowsthatthesuperpositionovervoltageiSmoreSeriousthantheotherMoreoverameasureofovervoltagesuppressionusingMOAisproposed，andthefeasibilityofitisprovedbydi