电力远程自动抄表系统--外文翻译

1、1英文原文：AutomaticmeterreadingsystemThepresentinventionrelatestoautomaticmeterreading.Moreparticularly,thepresentinventionrelatestoanautomatedsystemforremotelymonitoringapluralityofutilitymetersoncommandfromahostserverviaanRFoutboundbroadcast.BACKGROUNDOFTHEINVENTIONHistorically,metersmeasuringelectricalenergy,waterflow,gasusage,andthelikehaveusedmeasurementdevices,whichmechanicallymonitorthesubscriber'susageanddisplayareadingoftheusageatthemeteritself.Consequently,thereadingofthesemetershasrequir。

2、edthathumanmeterreadersphysicallygotothesiteofthemeterandmanuallydocumentthereadings.Clearly,thisapproachreliesveryheavilyonhumaninterventionand,thus,isverycostly,time-consuming,andpronetohumanerror.Asthenumberofmetersinatypicalutility'sserviceregionhasincreased,insomecasesintothemillions,humanmeterreadinghasbecomeprohibitiveintermsoftimeandmoney.Inresponse,varioussensingdeviceshavebeendevelopedtoautomaticallyreadutilitymetersandstorethemeterdataelectronically.Thesesensingdevices,usuallyoptical,。

3、magnetic,orphotoelectricinnature,arecoupledtothemetertorecordthemeterdata.Additionally,themetershavebeenequippedwithradiofrequency(RF)transceiversandcontroldeviceswhichenablethemeterstotransmitmeterdataoveranRFlinkwhenrequestedtodoso.Hand-helddeviceshavebeendevelopedwhichincludeRFtransceiversdesignedtointerfacewiththemeters'RFtransceivers.Thesehand-helddevicesenablethehumanmeterreadertosimplywalkbythemeter'slocation,transmitareadingrequestoveranRFlinkfromthehand-helddevicetothemeter'sreceivingde。

4、vice,waitforaresponsefromthemeter'ssensingandtransmittingdevice,andthenrecord,manuallyorelectronically,themeterdata.Similarly,meterreadingdeviceshavebeendevelopedfordrive-byreadingsystems.UtilityvansareequippedwithRFtransceiverssimilartothosedescribedinthehand-heldexampleabove.Thehumanmeterreaderdrivesbythesubscriber'slocation,withanautomatedreadingsystemintheutilityvan.Again,themetersarecommandedtoreportthemeterdata,whichisreceivedinthevanviaanRFlink,wherethedataisrecordedelectronically.Whileth。

5、ismethodologyimprovesuponthepreviousapproaches,itstillrequiresasignificantamountofhumaninterventionandtime.Recently,therehasbeenaconcertedefforttoaccomplishmeterreadingbyinstalling2fixedcommunicationnetworksthatwouldallowdatatoflowfromthemeterallthewaytothehostsystemwithouthumanintervention.Thesefixedcommunicationsnetworkscanoperateusingwirelineorradiotechnology.FIG.1showsaconventionalfixedcommunicationnetworkforautomatedmeterreading(AMR)technology.AsshowninFIG.1,afixedcommunicationnetworkhaving。

6、wirelinetechnologyinwhichutilitymeters10areconnectedtoawideareanetwork(WAN)consistingofasuitablecommunicationsmedium,includingordinarytelephonelines,orthepowerlinesthatfeedthemetersthemselves.Onedisadvantageofthisapproachhasbeenthatwhenanumberofmeterstransmitmeterdatanearlysimultaneously,theinherentlatencyonthewideareanetworkresultsinpacketcollisions,lostdata,garbleddata,andgeneraldegradationofintegrityacrossthesystem.Tocompensateforthecollisionsandinterferencebetweendatapackagesdestinedforthece。

7、ntralcomputer,duetothelatencyinherentintheWAN,variousmanagementschemeshavebeenemployedtoensurereliabledeliveryofthemeterdata.However,whilethisapproachmaybesuitableforsmallsystems,itdoesnotservetheneedsofautilitywhichmonitorsthousandsorevenmillionsofmeters.InanattempttobettermanagethetrafficintheWAN,approacheshavebeendevelopedwhereinmetercontroldevicessimilartothosedescribedabovehavebeenprogrammedtotransmitmeterdatainresponsetocommandsreceivedfromthecentralcomputerviatheWAN.Bylimitingthenumberofm。

8、eterreadingcommandstransmittedatagiventime,thecentralcomputercontrolsthevolumeofdatatransmittedsimultaneously.However,theadditionalWANtrafficfurtheraggravatedthedegradationofdataintegrityduetovariousWANlatencyeffects.Thus,whiletheseapproachesmayservetoeliminatetheneedforhumanmeterreaders,relianceontheWANhasproventheseapproachestobeunsatisfactoryforservicingthenumberofmetersinthetypicalserviceregion.Consequently,radiotechnologyhastendedtobethemediumofchoiceduetoitshigherdataratesandindependenceof。

9、thedistributionnetwork.ThelatestevolutionofautomatedmeterreadingsystemshavemadeuseofoutboundRFcommunicationsfromafixedsource(usuallytheutility'scentralstation),directlytoRFreceiversmountedonthemeters.Themetersarealsoequippedwithcontroldeviceswhichinitiatethetransferofmeterdatawhencommandedtodosobythefixedsource.ThemetersrespondviaaWANasinthepreviouswire-basedexample.OnedisadvantageoftheseapproachesisthatthereisstillfartoomuchinterferenceontheWANwhenallofthemetersrespondataboutthesametime.Thus,wh。

10、iletheseapproachesreducesomeoftheWANtraffic(byeliminatingoutboundcommandsovertheWAN),theyarestillunabletoaccommodatethelargenumberofmetersbeingpolled.3Itisworthyofnotethatthewire-basedsystemstypicallyuseasinglefrequencychannelandallowtheimpedanceandtransfercharacteristicsofthetransformersinthesubstationtopreventinjectionequipmentinonestationfrominterferingwithreceiversinanotherstation.Thisbuilt-inisolationinthenetworkmakestimedivisionmultiplexinglesscriticalthanforradiobasedmeteringsystems.Typica。