简介：AbridgearmprototypeofITERpoloidalfield(PF)convertermoduleshasbeendesignedandfabricated.Non-cophasecounterparallelconnectionischosenasthearmstructureoftheprototype.Amongallfactorsaffectingcurrentsharing,armstructureisthemainone.Duringthedesignofthearmprototype,anovelmethodbasedoninductancematrixesisemployedtoimprovethecurrentsharingofthebridgearm.Thetestresultsontheprototypeshowthatthecurrentsharingperformanceofthearmprototypeismuchbetterthanrelevantdesignrequirement,andthatthematrixmethodisveryeffectivetoanalyzeandsolvethecurrentsharingproblemsofthyristorconverters.

简介：Becausethelargermetallicsurroundsareheatedbytheeddycurrent,whichisgeneratedbytheACcurrentflowingthroughtheACbusbarintheInternationalThermonuclearExperimentalReactor(ITER)poloidalfield(PF)convertersystem,shieldingoftheACbusbarisrequiredtodecreasethetemperatureriseofthesurroundstosatisfythedesignrequirement.ThreespecialtypesofACbusbarwithnaturalcooling,aircoolingandwatercoolingbusbarstructurehavebeenproposedandinvestigatedinthispaper.Foreachcoolingscheme,a3Dfinitemodelbasedontheproposedstructurehasbeendevelopedtoperformtheelectromagneticandthermalanalysistopredicttheiroperationbehavior.Comparingtheanalysisresultsofthethreedifferentcoolingpatterns,watercoolinghasmoreadvantagesthantheotherpatternsanditisselectedtobethethermaldissipationpatternfortheACbusbarofITERPFconverterunit.TheapproachtoqualifythesuitablecoolingschemeinthispapercanbeprovidedasareferenceonthethermaldissipationdesignofACbusbarintheconvertersystem.

简介：Inresponsetothecurrentimbalancephenomenonanditsharmfulness,acurrentsharingcircuitmodelisbuiltup,whichrevealstheunderlyingcausesforthecurrentimbalancethroughaquantitativeanalysis.Then,afeasibleapproachofimprovement,namelyenlargementofthelengthofconnectionbusbars,isproposed.Aftertheamendment,itcanbeseenthatthecurrentsharingcoefficientisalmostunityunderratedorfaultcurrentconditions.

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简介：ISO/TC85/SC2(国际标准化组织/核能标准化技术委员会/辐射防护分技术委员会)第16届年会于2005年3月28日至3月31日在北京召开。

简介：利用电子衍射，X射线衍射和荧光光谱等方法研究了LnBaB0O16(Ln=La,Y)的结构特性，LnBaB9O16为单斜晶系，其中LaBaB9O16的晶胞参数a=1.3660nm,b=0.7882nm,c=1.6253nm,β=106.15°,YBaB9O16的晶胞参数a=1.3476nm,b=0.776nm,c=1.6040nm,β=106.38°，荧光光谱研究表明，这两种化合物结构不同，Y^3+在YBaB9O16结构中处于中心对称格位，而LaBaB9O16中La^3+的格位则无中心对称性，Gd^3+部分取代LaBaB9O16:Eu^3+中的La^3+可改善Eu^3+离子的发光性质，LaBaB9O16:Eu^3+在真空紫外区的吸收比较弱，这可能与硼氧比较小有关。