简介：Uptothefifties,bulkoilcircultbreaker（c.b.）wasthemainbreakertypeusedinChina.Fromthesixtieson,allEHVc.b.wereair-blasttype,butowingtotheirairleakageandfrequentmaintenanceworkrequired,alotofminimumoilc.b.wereimported;intheseventies,minimumoilc.b.wasthemainbreakertypeusedalloverthecountryinthevoltagerangeof6-220kV;atthebeginningoftheeighties,500kVSF6.c.b.wereputinserviceandgraduallyex-tendeddownto220kV,110kVandevento10kV,theirnumberisincreasing.Atthesametime,mediumvoltagevacuumc.b.beganto

简介：Afterfouryears'extensivelyscramblingrivers'exploitationrightsbypowercompanies,thecountablehydropowerresourcesarealmostsharedup.Inwater-abundantsouthwesternregion,fivelargegenerationgroupsdelimitedtheirownspheresonlargerivers.Sharpprivateenterprisesavailedthemselvesofeveryopportunitytograspthetargetsonsmallandmediumrivers.Asnumerousinvestorsswarmed,hydropowerconstructionenteredarealhightideperiod.'Atpresent,theproportionofexploitedhydroenergyisapproximately20%oftheexploitablewaterenergyinChina.Itwillbeenoughforthedatumtobecloseto60%inChina,otherwisemoreproblemswithecologicalenvironmentwouldfollow.Thehydropowertobedevelopedshallbelimitedwithin350GW,andthisisthetop,'saidWangShucheng,MinisterofMinistryofWaterResources.'Excessivemarketizationislikelytoleadendlesstroubleinhydropowerconstruction.Incasetheinvestmentinahydropowerprojectfails,thedestroytoecologicalenvironmentareverydifficulttoberestored,'saidPengTubiao,chiefengineerfromChinaHydropowerandWaterResourcesPlanningandDesigninstitute.

简介：Thispaperpresentsauniquenoveldesignofthephase-shiftedcascadehighvoltageinverter.Thehighvoltageinverterutilizesfewerpowerswitchesandsuppliesabalanceload.TheusageofphaseshifttransformerandphaseshiftingSPWMensuresthatinputandoutputharmonicwavecontentislowandoutputvoltagechange(du/dt)hasalowrate,meetingalltherequirementsofthepowerauthorities.Themostout-standingfeatureistheenergysavingwithveryfastcostrecovery.

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简介：<正>Accordingtopressreports,China’sfirstlongdistance,extra-highvoltagecableisexpectedtocrossQiongzhouStraitsbefore2006.

简介：<正>OnNovember12thisyear,JinpingCascadeIHydropowerStation,seatedonthelowerreachesofYalongRiverinSichuanProvince,startedtobeconstructed.ThestationisthesecondlargehydropowerprojecttobeconstructedonYalongRiverfollowingErtanHydropower

简介：InordertosolveabottleneckprobleminpowernetworksafetyoperationtheElectrotechnicalResearchInstituteundertheChineseAcademyofSciencehasfinishedadevelopmentworkofprototypehigh-temperaturesuperconductingcurrentlimiterwithindependentintellectualpropertyrightsonthebasisofatheoryadvancedonitsown.Suchalimiterhasovercomedisadvantagesinexistingonesworldwide.

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简介：Inordertopromotethedevelopmentofnewandrenewableenergytechnologies,theNationalDevelopmentandReformCommissionhasrecentlydecidedthatitwillgivebackingtothehigh-techindustrializationofnewandrenewableenergyresourceswithspecial-purposefundsduringtheperiodof2005-2007.Thestate-supportedkeypointsareasfollows.