Simplifiedmodelsofasingle-phasepowerelectronicinverterforrailwaypowersystemstabilityanalysis—Developmentandevaluation

交通系統穩定性旳簡化仿真模型分析電力電子逆變器旳開發與評估措施ElectricPowerSystemsResearchUseofpowerelectronicequipmenthasincreasedandintroducednewdynamicalphenomenainpowersystems.Forexample,newelectricrailvehicles(locomotives)equippedwithmodernpowerelectronictractionchainshavecausedsituationsoflow-frequencypoweroscillationsandinstabilityinsingle-phaserailwaypowersupplysystems.Thispaperpresentsthedevelopmentandimplementationofaninstantaneousvaluemodelandsimplifiedfundamentalfrequency(RMS)modelsofsuchanadvancedelectricrailvehicleinordertoinvestigatetheirrepresentationoflow-frequencydynamics.Thedynamicalbehaviourisstudiedbyuseofbothtime-domainsimulationsandlinearanalysis(eigenvalues)andthedegreeofsimplificationsregardingcontrollerdynamicsandpowersystemdynamicsarepresentedanddiscussed.AnenhancedRMSmodelistestedinordertoaccountfortheimpactoffastcurrentdynamicsonthelow-frequencybehaviour.TheresultsshowthatthisenhancedmodeliscorrespondingmorecloselytotheinstantaneousvaluemodelthanwhatcanbeobtainedbythetraditionalRMSsimplificationsandindicatethatcurrentdynamicsshouldbeincludedinstabilitystudiesinvolvingpowerelectronicinverters.Reviewofcontroltechniquesforinvertersparalleloperation

Thispaperpresentsstate-of-the-artreviewofcontrolmethodsappliedcurrentlytoparallelpowerelectronicinverters.Differentsystemarchitectures,theirmodesofoperation,managementandcontrolstrategieswillbeanalyzed;advantagesanddisadvantageswillbediscussed.Though,itisnoteasytogiveageneralviewatthestateoftheartfortheresearchareasinceitisrapidandgoingindifferentdirections,thispaperwillfocusonthemainstreams.Thispaperwillstartbybrieflyreviewingthecurrenttrendsinpowersupplysystemsandtheincreasingimportanceforincludingpowerelectronicdevices.Next,thedifferenttechniquestoparallelinverterssuggestedintheliteraturewillbechecked.Thesecanbecategorizedtothefollowingmainapproaches:master/slavecontroltechniques,current/powersharingcontroltechniques,andfrequency/voltagedroopcontroltechniques.Finally,basedonthereviewedstateoftheart,thestudyconcludesbycomparingthedifferentapproachesreported.Inaddition,theirweaknessesandstrengthsarestrained.Controlofinverter-basedmicro-grids

Thepredictedgrowthofsmall-scalenon-50/60

Hzpowersourcesandthedesiretobeabletosupportloadsindependentlyofthepublicelectricitygridrequiresthedevelopmentinverter-basedmicro-grids.Powerelectronicinterfaceshaveverydifferentcharacteristicstoconventionalelectricalmachinesand,therefore,differentoperation,controlandprotectionschemesarerequired.Attentionalsoneedstobegiventothedominanceofsingle-phaseharmonicallydistortingloadsinsomenetworksandcontrolschemesputinplacethatmaintainvoltagequality.Acontrolschemethatexploitsthecontrollabilityofinverterstooperateamicro-gridandprovidegoodpowerqualityisexaminedandcomparedwithbothtraditionalpowersystemsandwithcontrolofdc/dcpowerconverters.Thelimitationsofcommunicationandcontrolbandwidtharediscussed.Experimentalresultsareusedtoillustratetheperformancethatcanbeachievedwithvariouscombinationsoflinearandnon-linear,three-phaseandsingle-phaseloads.基于變頻功能旳微電網/獨立式電網/區域電網控制實行與研究Quality-drivenmodel-basedarchitecturesynthesisforreal-timeembeddedSoCs

SystemsArchitectureTherecentspectacularprogressinmodernmicroelectronicscreatedabigstimulustowardsdevelopmentofembeddedsystems.Unfortunately,italsointroducedunusualcomplexitywhichresultsinmanyseriousissuesthatcannotberesolvedwithoutnewmoreadequatedevelopmentmethodsandelectronicdesignautomationtoolsforthesystem-leveldesign.Thispaperdiscussestheproblemofanefficientmodel-basedmulti-objectiveoptimalarchitecturesynthesisforcomplexhardreal-timeembeddedsystems,whenusingasanexampleasystem-levelarchitectureexplorationandsynthesismethodthatwedeveloped.系統構造與架構學學報基于質量驅動模型旳構造分析與實行嵌入式控制/反饋/仿真軟件措施Researchanddevelopmentofmaximumpowertransfertrackingsystemforsolarcellunitbymatchingimpedance

RenewableEnergyEmployingthetheoremthatmatchingimpedanceproducesmaximumpowertransfer,thecurrentstudydevelopsalow-costandhighlyefficient“maximumpowerpointtrackerforasolarcellunit,”forthepurposeofallowingasolarcelltoachieveoptimalpowertransferunderdifferentsolarintensitiesandtemperatures.Circuitcontroltakesasingle-chipmicroprocessorasthecoreandtheboostercircuitdesignundergoesthesolarcellchargingoperationeventhoughthesolarcelloutputvoltageislowerthantheratedstoragebatteryvoltage.Experimentsconductedinthisstudyprovethatthetrackerthisstudydevelopseffectivelyenhancestheutilizationefficiencyofasolarcell.Whenasolarcellisatanoutputvoltageabove30%oftheratedvoltage,itcanchargeastoragebattery.Whenitreachesabove80%oftheratedvoltage,itspowerconversionefficiencycanreachabove85%.Thechargeanddischargemanagementmechanismofthedevicealsoavoidsexcessivechargeanddischargeofthestoragebattery,andextendsstoragebatterylongevity.Areviewofpowerconvertertopologiesforwindgenerators

大型/中型/小型風力發電機用逆變器/變頻器技術回憶與總結反思Windenergyconversionsystemshavebecomeafocalpointintheresearchofrenewableenergysources.Thisisinnosmallpartduetotherapidadvancesinthesizeofwindgeneratorsaswellasthedevelopmentofpowerelectronicsandtheirapplicabilityinwindenergyextraction.Thispaperprovidesacomprehensivereviewofpastandpresentconvertertopologiesapplicabletopermanentmagnetgenerators,inductiongenerators,synchronousgeneratorsanddoublyfedinductiongenerators.Themanydifferentgenerator–convertercombinationsarecomparedonthebasisoftopology,cost,efficiency,powerconsumptionandcontrolcomplexity.Thefeaturesofeachgenerator–converterconfigurationareconsideredinthecontextofwindturbinesystems.Revivalbyautomationofinductiongeneratorfordistributedpowersystems,inRomanianacademicresearch

改善型旳自動化導航式分布電力系統發電機學術研究旳開發階段Thepaperapproachesthehalf-centuryhistoryandthemainresearchresultsoftheacademicstaffandresearchersfrom“Politehnica”UniversityofTimisoara(Universitatea“Politehnica”Timisoara—UPT)andtheircollaborationwiththeacademic,researchandproductionenvironmentconcerningtheuseofinductionmachineaspowersupplyinmicrohydroplantsandwindmillsinparticular;fromamongthesecollaboratorswemention:TheRomanianAcademy—TimisoaraBranch,TheInstituteforAutomationIPA—TimisoaraBranch,TheResearchandModernizationInstituteforEnergeticsICEMENERGBucharest,TheNationalInstituteforHeatEnginesINMTBucharest,TheMachineConstructionWorksUCMR—Resita,“Electroputere”Works—Craiovaand“Electromotor”Works—Timisoara.ThepaperaimsatpresentingtheoriginalresearchresultsatUPTagainstthebackgroundofgeneralresearchfromallovertheworldfocusedonrevivaltheinductiongeneratorbyautomation.Front-endelectronicsandtriggersystems—Statusandchallenges

NuclearInstrumentsandMethodsinPhysicsResearchSectionA:Accelerators,Spectrometers,DetectorsandAssociatedEquipmentThepastquartercenturyhasbroughtaboutarevolutioninfront-endelectronicsforlarge-scaledetectorsystems.Customintegratedcircuitsspecificallytailoredtotherequirementsoflargedetectorsystemshaveprovidedunprecedentedperformanceandenabledsystemsthatonceweredeemedimpossible.Theevolutionofintegratedcircuitreadoutsinstripdetectorsissummarized,thepresentstatusdescribed,andchallengesposedbythesLHCandILCarediscussed.Performancerequirementsincrease,butkeyconsiderationsremainasinthepast:powerdissipation,material,andservices.SmallerCMOSfeaturesizeswillnotreducethepowerrequiredforthedesirednoiselevels,butwillimprovedigitalpowerefficiency.Significantimprovementsappeartobepracticalinmoreefficientpowerdistribution.Enhanceddigitalelectronicshaveprovidedpowerfultriggerprocessorsthatgreatlyimprovethetriggerefficiency.Indatareadoutsystems,theyalsoimprovedatathroughput,whilereducingpowerrequirements.Concurrentlywithnewdevelopmentsinhighenergyphysics,detectorsystemsforcosmologyandastrophysicshavemadegreatstrides.Asanexample,alarge-scalereadoutforsuperconductingbolometerarraysisdescribed.核電用電力電子、電力系統及自動化設備電子電路旳功率放大循環智能化供電系統：能量儲備電池儲能與戶用新能源供電/家庭取暖裝置Intelligentuninterruptiblepowersupplysystemwithback-upfuelcell/batteryhybridpowersource

Thispaperpresentsthedevelopmentofanintelligentuninterruptiblepowersupply(UPS)systemwithahybridpowersourcethatcomprisesaproton-exchangemembranefuelcell(PEMFC)andabattery.AttentionisfocusedonthearchitectureoftheUPShybridsystemandthedataacquisitionandcontrolofthePEMFC.Specifically,thehybridUPSsystemconsistsofalow-cost60-cell300

WPEMFCstack,a3-celllead–acidbattery,anactivepowerfactorcorrectionac–dcrectifier,ahalf-bridgedc–acinverter,adc–dcconverter,anac–dcchargerandtheircontrolunitsbasedonadigitalsignalprocessorTMS320F240,otherintegratedcircuitchips,andasimplenetworkmanagementprotocoladapter.Experimentaltestsandtheoreticalstudiesareconducted.First,themajorparametersofthePEMFCareexperimentallyobtainedandevaluated.ThenanintelligentcontrolstrategyforthePEMFCstackisproposedandimplemented.Finally,theperformanceofthehybridUPSsystemismeasuredandanalyzed.Photovoltaicscavengingsystems:Modelingandoptimization

Microelectronics微電子學學報太陽能系統發電效能/效率/轉化率旳建模與優化Theinterestinembeddedportablesystemsandwirelesssensornetworks(WSNs)thatscavengeenergyfromtheenvironmenthasbeenincreasingoverthelastyears.Thankstotheprogressinthedesignoflow-powercircuits,suchdevicesconsumelessandlesspowerandarepromisingcandidatestoperformcontinuedoperationbytheuseofrenewableenergysources.Theadoptionofmaximumpowerpointtracking(MPPT)techniquesinphotovoltaicscavengersincreasestheenergyharvestingefficiencyandleadstoseveralbenefitssuchasthepossibilitytoshrinkthesizeofphotovoltaicmodulesandenergyreservoirs.Unfortunately,theoptimizationofthisprocessundernon-stationarylightconditionsisstillakeydesignchallengeandthedevelopmentofaphotovoltaicharvesterhastobeprecededbyextensivesimulations.Weproposeadetailedmodelofthesolarcellthatpredictstheinstantaneouspowercollectedbythepanelandimprovesthesimulationofharvestersystems.Furthermore,thepaperfocusesonamethodologyforoptimizingthedesignofMPPTsolarharvestersforself-poweredembeddedsystemsandpresentsimprovementsinthecircuitarchitecturewithrespecttoourpreviousimplementation.Experimentalresultsshowthattheproposeddesignguidelinesallowtoincrementglobalefficiencyandtoreducethepowerconsumptionofthescavenger.Transform-domainandDSPbasedsecurespeechcommunicationsystem

基于DSP旳工作場所、近距離戶外活動對講裝置設計時/頻域互換安全保密通話穩定性MicroprocessorsandMicrosystems微處理器和微系統學學報Securespeechcommunicationhasbeenofgreatsignificanceincivil,commercialandparticularlyinmilitarycommunicationsystems.Speechscramblersplayamajorroleinthesesystemsandtransform-domain,specially,DCT(DiscreteCosineTransform)basedencryptionofspeechhasoftenbeenapreferablechoiceforresearchersandengineers.Insuchsystems,besidessecurity,removalofredundantinformationandtheexecutionspeedofthealgorithmshavealsobeenthemainfocusofresearchandexploration.Inthispaper,weconcentrateontheinvestigationofthesethreeparametersingeneralandsecurityandspeedinparticular.InthisresearchtheseattributesareenvisagedbyexploitingITU-TG.723.1speechcodec,DCTbasedspeechencryptionalgorithmandTexasInstruments’32-bitfloating-pointDSP(DigitalSignalProcessor)TMS320C6711,respectively.Thiswork,infactisacontinuationandanadvancementoftheworkcarriedoutbyJameeletal.[A.Jameel,M.Y.Siyal,N.Ikram,ARobustSecureSpeechCommunicationSystemusingG.723.1andTMS320C6711DSP,MicroprocessorsandMicrosystems30(1)()26–32.]inwhichtheypresentedaredundancies-free,secureandfastspeechcommunicationsystemusingG.723.1codec,time-domainspeechscramblingtechniquesandTexasInstrumentsTMS320C6711DSP.Onthecontrary,inthisexplorationthesamesystemisimprovedsignificantlyintermsofsecurityandspeed.InordertoreduceresidualintelligibilitytherebytoenhancesecurityanewDCTbasedalgorithmusingsub-framingandlookuptableisproposed,implementedandanalyzed.Intermsofspeed,thereferencecodeofG.723.1isfurtheroptimizedonadvancedlevel.Additionally,theschemedisdesignedinsuchawaythatitalsodiminishestalkspurtandintonationpresentintheoriginalspeechsignalwhich,asaresult,increasesthelevelofsecurity.Hencearedundancies-free,secureandhighspeedcommunicationsystemhasbeenproposed,implementedandanalyzedusingvarioustypesofspeechsegments.Theresultsshowthattheproposedsystemissuitableforreal-timecivil,commercialandmilitaryapplications.Studyofamultiphaseinterleavedstep-upconverterforfuelcellhighpowerapplication