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DOC-火災報警器中英文文獻翻譯--基于單片機的火災探測和監(jiān)控系統(tǒng)-單片機外文文獻原稿和譯文原稿Multiplesingle-chipmicrocomputerapproachtofiredetectionandmonitoringsystemA.J.AI-Khalili,MSc,PhDD.AI-Khalili,MSc,PhDM.S.Khassem,MScIndexingterm:Hazards,Design,PlantconditionmonitoringAbstract:Acompletesystemforfiredetectionandalarmmonitoringhasbeenproposedforcomplexplants.Thesystemusesmultiplesinglechiparchitectureattachedtoapartyline.Thecontrolalgorithmisbasedonatwo-levelhierarchyofdecisionmaking,thusthecomplexityisdistributed.Acompletecircuitdiagramisgivenforthelocalandthecentralstationwithrequirementsforthesoftwarestructure.Thedesigniskeptingeneralformsuchthatitcanbeadaptedtoamultitudeofplantconfigurations.Itisparticularlyshownhownewdevelopmentsintechnology,especiallyCMOSsinglechipdevices,areincorporatedinthesystemdesigntoreducethecomplexityoftheoverallhardware,e.g.bydecomposingthesystemsuchthatlowerlevelsofhierarchyareabletohavesomeautonomyindecisionmaking,andthusamorecomplexdecisionissolvedinasimpledistributedmethod.1IntroductionRegulatoryrequirementsformosthighriskplantsandbuildingsmandatetheinstallationoffiredetectionandwarningsystemsforallsensitiveareasoftheplantorthebuilding.Mostfirecodesstatetherequirementformonitoringandcontrolpecificallyrelatedtoatypeofaplantorbuildingsuchaschemicalplants,petroleum,snuclearplants,residentialhigh-risesetc.Ageneralconclusionofthesecodescanbespecifiedasthefollowingrequirements:(a)Thesourceofalldetectorsignalsshouldbeexactlyidentifiablebythecentralstation(b)Anextrapathofcommunicationbetweenthecentralstationandalllocalcontrollers(c)Directmeansofcontrolofalarmandcentralequipmentbythecentralstation(d)Meansofcommunicationbetweenthecentralstationandthefiredepartment(e)Availabilityofemergencypowersupply.Thecodesusuallyalsospecifythetypesandfrequencyoftestsforallequipment.Afiredetectionandalarmsystemisacombinationofdevicesdesignedtosignalanalarmincaseofafire.Thesystemmayalsoaccomplishfancontrol,firedoorholdorrelease,elevatorrecall,emergencylightingcontrolandotheremergencyfunctions.Theseadditionalfunctionssupplementthebasicsystemwhichconsistsofdetectionandalarmdevicesandcentralcontrolunit.Technologyhasaninfluenceonsystemarchitecture.Whentechnologychanges,thearchitecturehastoberevisedtotakeadvantageofthesechanges.Inrecentyears,VLSItechnologyhasbeenadvancingatanexponentialrate.FirstNMOSand,inthelastyearortwo,CMOSchipshavebeenproducedwiththesamepackingdensitywithmoregatesperchipyetatalowerpowerconsumptionthanNMOS.Surelythischangeintechnologymustaffectourdesignofhardwareatboththechipandthesystemlevel.Atthechiplevel,singlechipsarenowbeingproducedwhichareequivalenttoboardlevelsofonlythepreviousyearortwo.Thesechipshavemicroprocessor,memoryinRAMandROM,IOPortsbothserialandparallel,A/Dtimer,flagsandotherfunctionsonchip.Atthesystemlevel,thenewchipsmakenewarchitecturespossible.Theobjectiveofthispaperistoshowhowtechnologycaninfluencesystemarchitectureinthefieldoffirecontrol.Thenewhighdensitysinglechipmicrocontrollersareincorporatedinthedesignofalargescalesystemandyetweobtainasmallersystemwithabetterperformance.Intermsoffiredetectionandalarmmonitoring,thisisreflecteddirectlyinthelocalstationhardware,becauseoftheirremotenessandpowersupplyrequirements.AcompletelocalstationcanbedesignedaroundasingleCMOSchipwithpowerconsumptionofafewmWdependingonsystemoperation.Thisapproachreducesthecostandcomplexityofdesign,implementationandmaintenanceandprovideseasilyexpandableandportabledesign.Thisimplementationwasnotpossiblewitholdtechnology.Mostoffiredetection/monitoringsystemsavailablearetailoredtowardsaspecificapplicationandlacktheuseofrecentadvancesinCMOSVLSItechnology.Inthisstudy,wedevelopafiredetection/monitoringsystemwhichisgeneralinconcept,readilyimplementableinamultitudeofapplicationsforearlydetectionofafirebeforeitbecomescritical,forequipmentandevacuationofpersonnel.Here,weproposeacentralcontrolanddistributedcontrol/detection/monitoringwithadequatecommunication,whereuseismadeofsingle-chipmicrocontrollersinthelocalstations,thusimprovingcontrollabilityandobservabilityofthemonitoringprocess.2DetectionandalarmdevicesAbasicfiredetectionsystemconsistsoftwoparts,detectionandannunciation.Anautomaticdetectiondevice,suchasaheat,smokeorflamedetector,ultravioletorinfrareddetectorsorflameflicker,isbasedondetectingthebyproductofacombustion.Smokedetectors,ofbothionizationandopticaltypes,arethemostcommonlyuseddetectordevices.WhenatypicaldetectorofthistypeentersthealarmstateitscurrentconsumptionincreasesfromthepAtothemArange(say,fromamere15pAinthedormantmodeto60mA)intheactivemode.Inmanydetectorsthedetectoroutputvoltageiswelldefinedundervariousoperatingconditions,suchasthosegiveninTable1.Themoresensitivethedetector,themoresusceptibleitistofalsealarms.Inordertocontrolthedetectorprecisely,eitherofthefollowingmethodsisused:acoincidencetechniquecanbebuiltintothedetector,orafilteringtechniquesuchthatalogiccircuitbecomesactiveonlyifxalarmsaredetectedwithinatimeperiodT.Thedetectiontechniquedependsgreatlyonthelocationandplantbeingprotected;smokedetectorsareusedforsleepingareas,infraredorultravioletradiationareusedwhenflammableliquidsarebeinghandled,heatdetectorsareusedforfiresuppressionorextinguishingsystems.Ingeneral,lifeandpropertyprotectionhavedifferentapproaches.Alarmdevices,apartfromtheusualaudibleorvisiblealarms,mayincorporatesolidstatesoundreproductionandemergencyvoicecommunicationorprintersthatrecordtime,date,locationandotherinformationrequiredbythestandardcodeofpracticeforfireprotectionforcomplexplants.Heaviside[4]hasanexcellentreviewofalltypesofdetectorsandextinguishersystems.2.1ControlphilosophyanddivisionoflabourOurcontrolphilosophyisimplementedhierarchically.Threelevelsofsystemhierarchyareimplemented,withtwolevelsofdecisionmaking.Thereisnocommunicationbetweenequipmentonthesamelevel.Interactionbetweenlevelsoccursbyupwardstransferofinformationregardingthestatusofthesubsystemsanddownwardstransferofcommands.ThisisshowninFig.1whereatlevel1isthecentralstationmicrocomputerandistheultimatedecisionmaker(whennotinmanualmode).Atlevel2arethelocalcontrollers,whichresideinthelocalstations.Atlevel3aretheactualdetectorsandactuators.Amanualmodeofoperationisprovidedatalllevels.Informationregardingthestatusofalldetectorsistransmittedonaperareabasistothelocalcontrollers.Theirinformationiscondensedandtransmittedupwardtothecentralmicrocomputer.Transferofstatusisalwaysunidirectionalandupwards.Transferofcommandsisalwaysunidirectionalanddownwards,withexpansionatthelocalcontrollevel.Thisapproachpreservesthestrictrulesofthehierarchyforexactmonitoringdetectionandalarmsystemsassociatedwithhighriskplants.Theclassificationofthetwolayersofcontrolsisbaseduponlayersofdecisionmaking,withrespecttothefactsthat(a)Whenthedecisiontimecomes,themakingandimplementationofadecisioncannotbepostponed(b)Thedecisionshaveuncertainty(c)Itwillisolatelocaldecisions(e.g.locallywemighthaveanalarmalthoughtheremaybeafaultwiththesystem)3GeneralhardwareI:Fig.2depictsourdesigninthesimplestofforms.Thesystemusesanopenpartylineapproachwithfourconductorcablesgoinginaloopsharedbyalltheremotedevicesandthecontrolpanel.Thisapproachissimpleinconceptandiseconomicallyfeasible.However,onemajordisadvantageisthedependencyonasinglecableforpowerandsignaling.Incaseswherereliabilityisofextremeimportance,twooreventhreecablestakingdifferentroutesthroughoutthesystemmaybeconnectedinparallel.Fig.3givesthedrivercircuitryrequiredtoderiveanexpandablebus.Thisdesigntakesadvantageofrecentadvancesinthesinglechipmicrocomputertechnologytoreducetheinterfacebetweenthecentralstationandthelocalstations.3.1CentralcontroltaskAcentralunitprovidesacentralizedpointtomonitorandcontrolthesystemactivities.Inthesystemtobedescribedthecentralcontrolunitservesafivefoldpurpose.(i)Itreceivesinformationfromthelocalstationsandoperatesthealarmsandotheroutputdevices.(ii)Itnotifiestheoperatorincaseofsystemmalfunction.(iii)Itprovidesanoverallsystemcontrolmanualandautomatic.(iu)Itprovidesasystemtestpointoflocalstationsanditself.(u)Itprovidesacentralpointforobservation,learningandadaptation.3.2LocalstationsThelocalstationscantakelocaldecisionsregardingrecognitionofarisksituation,andactindependentlyonlocalaffairs.Inthistechniquewedependon‘load-typecoordination’,e.g.thelowerlevelunitsrecognizetheexistenceofotherdecisionunitsonthesamelevel;thecentralorthetoplevelprovidesthelowerunitswithamodeloftherelationshipbetweenitsactionandtheresponseofthesystem.Itisevidentthatapowerfulmachineisrequiredatthisstagesothatalltherequiredfunctionscanbeimplemented.Theavailabilityofthenewgenerationofmicrochipsmakesthisarchitectureafeasiblesolution.Asinglechipmicrocomputerwaschosenoverdiscretedigitalandanaloguedevicestointerfacetothefielddevicesandtothecentralmicrocomputer.Thisisthemainreasonthatpreviouslythisapproachwasnotfeasible.Inselectingthemicrocomputerforthelocalstations,thecriterionwastherequirementforachipwhichcontainsthemostintegrationoftheanalogueanddigitalportsrequiredfortheinterfaceandtheutilizationofCMOStechnologyowingtoremotenessofthelocalstations.ThechoicewastheMotorola68HC11A4,forthefollowingreasons:(a)ItisCMOStechnology;thisreducespowerconsumption.(b)IthasaUARTonboard;thisfacilitatesserialcommunication.(e)Ithasana/dconverteronboard;thiseliminatesanexternalA/D.(d)Ithas4KofROM,256bytesofRAM,512bytesofEERROMwith401/0linesanda16bittimer;thissatisfiedallourmemoryand1/0requirementsatthelocalstationside.4SystemimplementationThelocalstation:Fig.3istheblockdiagramofthecircuitusedtoutilizetheMC68HCllA4asaremotefiredetectingcircuitwhileFig.4illustratesthesamecircuitinanexpandedform.Itcanbeseenthatthesinglemicrocontrollercanbeusedtomonitormorethanonedetector,thusreducingsystemcost.Thelooppowersupply,whichisusuallybetween28and26V,isfurtherregulatedbya5V100mAmonolithiclowpowervoltageregulatortosupplypowertothemicrocontroller.Theonboardoscillator,coupledwithanexternalcrystalof2.4576MHz,suppliesthemicrocontrollerwithitstimingsignalwhichisdividedinternallybyfourtoyieldaprocessorfrequencyof614.4kHz,whichisanevenmultipleoftheRS232[7]baudrategenerator.InthisSectiontheterm‘supervisedinputoroutput’willbeusedtomeanthatthefunctioninquestionismonitoredforopen-andshort-circuitconditionsinadditiontoitsothernormalfunctions.MoreinformationcanbefoundinReference9.5Mainloop6ConclusionThispaperdescribesthedevelopmentofalargescalefiredetectionandalarmsystemusingmulti-singlechipmicrocomputers.Thearchitectureusedisatwo-levelhierarchyofdecisionmaking.ThisarchitectureismadepossiblebythenewCMOSmicrocontrollerswhichrepresentahighpackingdensityatalowpowerconsumptionyetarepowerfulindataprocessingandthusindecisionmaking.Eachlocalstationcouldmakeanautonomousdecisionifthehigherlevelofhierarchyallowsittodoso.Ithasbeentriedtokeepthesystemdesigningeneralformatsoitcanbeadaptedtovaryingsituations.Aprototypeofthedescribedsystemhasbeenbuiltandtested[10].ThecontrolpartofthecentralstationisimplementedwithadevelopmentcardbasedonMC68000microprocessor(MEX68KECB,byMotorola),whichhasabuilt-inmonitorcalledTutor.Theapplicationprogramsweredevelopedusingthefeaturesprovidedbythismonitor.Thelocalstations’controllersweredesignedusingtheMC68705R3,single-chipmicrocontroller.7References1‘Fireprotectionguidelinesfornuclearpowerplants’,USNRCRegulatoryGuide1.1202BAGCHI,C.N.:‘Amulti-leveldistributedmicroprocessorsystemforanuclearpowerplantfireprotectionsystemcontrols,monitoring,andcommunication’,IEEETrans.,19823PUCILL,P.M.:‘Firehazardprotection,detectionandmonitoringsystems’,Sea.Con,2,ProceedingsofSymposiumonADVinoffshoreandterminalmeasurementandcontrolsystems,Brighton,England,March1979,pp.353-3634HEAVISID,L.:‘Offshorefireandexplosiondetectionandfixedfire’.OffshoreTechnologicalConference,12thAnnualProceedings,Houston,Texas,May1980,pp.509-5225CELLENTANI,E.N.,andHUMPHREY,W.Y.:‘Coordinateddetection/communicationapproachtofireprotection’,Specify:Eng.,6‘MotorolaMicroprocessorsDataManual’(MotorolaSemiconductorProducts,Austin,Texas,USA)7ElectronicIndustriesAssociation:‘Interfacebetweendataterminalequipmentanddatacommunicationequipmentemployingserialbinarydatainterchange’(EIAStandardRS-232,Washington,DC,1969)8MESAROVIC,M.D.,MACKO,D.,TAKAHARA,Y.:‘Theoryofhierarchicalmultilevelsystems’(AcademicPress,1970)9KASSEM,M.:‘Firealarmsystems’,MSc.thesis,Dept.ofElec.&Comp.Eng.,ConcordiaUniversity,Montreal,Canada,198510LIE,P.,andKOTAMARTI,U.:‘Thedesignofafirealarmsystemusingmicroprocessors’,C481Project,Dept.ofElec.andComp.Eng.,ConcordiaUniversity,Montreal,Canada,1986譯文基于單片機的火災探測和監(jiān)控系統(tǒng)A.J.AI-Khalili,MSc,PhDD.AI-Khalili,MSc,PhDM.S.Khassem,MSc關鍵詞:危險,設計,設備狀態(tài)監(jiān)測摘要:火災探測及報警監(jiān)控已成為一個復雜而完整的體系。該系統(tǒng)采用多個單芯片架構到一條主線上。該控制算法是基于兩級決策層次,因此分配了復雜性。一個完整的電路原理圖,給出了主、分控制器所需的軟件的結(jié)構要求。設計延續(xù)一般形式,這樣可以適應于多種系統(tǒng)的配置。尤其顯示出新的技術發(fā)展,特別是CMOS單芯片器件,在系統(tǒng)設計中的使用,以減少整體硬件的復雜性,例如,通過分解系統(tǒng),這樣的層次較低水平的控制器能夠有一些決策自主權,用簡單的分布式的方法解決了復雜的決策。1、引言大多數(shù)高風險地區(qū)和建筑物的管理要求安裝火災探測報警系統(tǒng)。多數(shù)國家消防規(guī)范的要求監(jiān)測和控制具體的是危險場合或建筑物,如化工廠,石油類,核電廠,住宅高樓等這些場合的一般性質(zhì)可以指定為下列要求:(一)所有探測器信號源信號能被主處理器準確識別。(二)主從控制器有另外的溝通路徑。(三)檢測報警和主控制設備由控制中心控制。(四)火災現(xiàn)場和控制中心的通訊。(五)提供的應急電源。它也被用來應對特殊情況和進行深被檢測?;馂奶綔y及報警系統(tǒng)是一個旨在信號,在一旦發(fā)生火警報警裝置的組合。該系統(tǒng)也可實現(xiàn)風扇控制,防火門關閉或釋放,電梯鎖定,應急照明控制和其他緊急任務。這些額外的功能補充由檢測和報警裝置和中央控制單元組成。技術對系統(tǒng)結(jié)構有很深的影響。當技術的變革,該架構必須修訂,以利用這些新的功能變化。近年來,超大規(guī)模集成電路技術已經(jīng)大大進步。第一,NMOS在過去的一年或兩年,CMOS芯片以相同的堆積密度擁有更多的門和更低的功耗。當然這種技術的變化必然影響在芯片和系統(tǒng)級我們的硬件設計。在芯片級,單芯片現(xiàn)在正在制作的是只相當于上一年或兩年的水平。這些芯片有微處理器,RAM和ROM,IO端口存儲器串行和并行,A/D轉(zhuǎn)換定時器,和其他功能的芯片。在系統(tǒng)級,新的芯片做出新的結(jié)構成為可能。本文的目的是體現(xiàn)技術如何影響消防控制領域的系統(tǒng)結(jié)構。新的高密度的單芯片微控制器納入一個大系統(tǒng)的設計,但我們可以得到了更好的性能,更小的系統(tǒng)。在火災探測和報警監(jiān)控系統(tǒng)中,這是直接反映在分控制站的硬件,因為地處偏遠和電源的要求。一個完整的分控制站可以圍繞著一個帶電源的CMOS芯片設計。這種方法降低了成本和設計復雜性,方便實施和維護,并提供易于擴展和便攜式設計。這是舊技術不可能實現(xiàn)的。大部分火災檢測/監(jiān)測系統(tǒng)提供特定的應用程序,缺乏對CMOS超大規(guī)模集成電路技術的應用。在這項研究中,我們開發(fā)了火災檢測/監(jiān)測系統(tǒng),常規(guī)設計,易于執(zhí)行的早期發(fā)現(xiàn)火警。在這里,我們提出一個中央控制和分發(fā)控制/檢測/充分的溝通,如果使用的單芯片微控制器在分控制站,從而提高可控性和可觀性的監(jiān)測過程。2、檢測和報警裝置一個基本的火災探測系統(tǒng)由兩部分組成,檢測和報警。自動檢測設備有比如熱,煙霧或火焰檢測器,紫外線或紅外線探測器或火焰閃爍,是基于檢測一個燃燒的副產(chǎn)品。煙霧探測器都電離和光類型,是最常用的檢測設備。當這種類型的典型探測器進入報警狀態(tài)產(chǎn)生的電流信號會從PA變成MA(比如,從單純的15pA在休眠模式下為60毫安)在主動模式。在許多探測器的檢測器輸出電壓明確在各種運行條件,例如見表1。越是敏感的檢測器,它更容易受到虛假警報。為了控制探測器的精確,可使用下列方法:過濾技術,這樣的邏輯電路成為活躍僅當x警報的時間內(nèi)檢測周期T。檢測技術在很大程度上取決于地點和植物受到保護,煙霧探測器是睡覺的地方,紅外線和紫外線輻射探測器,檢測易燃液體燃燒,熱探測器用于滅火和滅火系統(tǒng)。一般來說,生命和財產(chǎn)保護有不同的做法。報警裝置,從通常的聲響或視覺報警外,還可以采用固態(tài)的聲音再現(xiàn)和緊急話音通信或打印機,記錄時間,日期,地點和其他資料。Heavisid[4]擁有一支優(yōu)秀的審查探測器和滅火器的各種制度。2.1控制理念和分工我們的理念是實施控制等級。三個層次的系統(tǒng)級的實施,兩個級別的決策。之間沒有設備,在同一層次的溝通。交互各級之間發(fā)生了向上的信息傳輸有關的子系統(tǒng)和向下狀態(tài)轉(zhuǎn)移的命令。這是圖所示。1,其中第1級是中央控制站,是微機最終(在不手動模式)決策者。第2級是當?shù)乜刂破?,建立在當?shù)氐恼?。?級是實際檢測器和驅(qū)動器。在各級提供手操作模式。所有探測器的數(shù)據(jù)和分處理器是當?shù)乜刂频幕A。他們將信息濃縮,并轉(zhuǎn)交中央處理器。信息傳遞的地位始終是單向及以上。命令傳輸是單向的總是向下,并在擴大局部控制的水平。這種方法保留了層次的準確監(jiān)測檢測和嚴格的規(guī)則高風險的核電站警報系統(tǒng)。兩個控制層的分類是基于決策層。(一)在屆時的決定,提出和決定的執(zhí)行情況不能再拖延(二)決定的不確定性(三)將隔離當?shù)氐臎Q定(例如,我們可能會在當?shù)貓缶?,但有可能有故障系統(tǒng))3、硬件圖.2描繪了我們的設計最簡單的形式。這個系統(tǒng)采用四個導體開放的路線,在所有遠程共享一個循環(huán)電纜設備和控制面板。這種方法簡單,經(jīng)濟上可行。但是,一個主要缺點是對一個單一的電力和信號電纜的依賴。在重要環(huán)境下,可靠性是極其重要的。固可采用兩個甚至三個電纜采取不同的線路連接,可并行連接。圖.3是驅(qū)動電路必須得一個擴展總線。采用這種設計在單片機技術的最新發(fā)展優(yōu)勢減少與中央控制站和地方控制站的接口。3.1中央控制任務中央站點提供了一個集中點,以監(jiān)測和控制系統(tǒng)的活動。在該系統(tǒng)介紹了中央控制單元的目的(一)它得到了分控制站的信息和控制警鐘及其他輸出設備。(二)它提示在系統(tǒng)出現(xiàn)故障時的操作。(三)它提供了一個全面系統(tǒng)的手動和自動控制。(四),它提供了中央和分站的系統(tǒng)測試點。(五)它提供了一個中心點觀察,學習和適應。3.2分控制站分控制站的決定可以控制處理當?shù)氐男畔?。這種技術我們就依靠負載型協(xié)調(diào)下級單位,承認在同一水平上的其他決定單位的存在;中央或高層提供了一個較低的單位模型之間的行動和系統(tǒng)響應的關系。很明顯,一個強大的機器,需要在這個階段,使所有需要的功能得到有效執(zhí)行。該芯片的新一代供應使得該體系結(jié)構的解決變得可行。單片機被選中了離散的數(shù)字和模擬設備接口,到外地設備和中央微機。這是最主要的原因,以前這種做法是不可行的。該芯片的選擇的,包含要求的模擬和數(shù)字接口所需的端口和CMOS技術的運用,由于地處偏僻的分控制站最一體化。這個選擇是摩托羅拉68HC11A4,理由如下:(1)它是CMOS技術,這可減少電力消耗。(2)它有一個UART,這有利于串行通信。(3)它有一個A/D轉(zhuǎn)換器上,這消除了外部A/D轉(zhuǎn)換(4)它有一個4K的ROM,256K內(nèi)存,512KEERROM字節(jié)40個I/O端口的線路和一個16位定時器;符合分控制站所有的內(nèi)存和1/0的要求。4、系統(tǒng)實施分控制站:圖.3是用于一個遠程火災報警MC68HCllA4電路框圖檢測電路:圖.4這
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