電氣自動(dòng)化畢業(yè)設(shè)計(jì)外文文獻(xiàn)翻譯

譯文：設(shè)定蒸汽發(fā)生器的需求1自然需求〔或者是三者使用的一種混合使用。是作為一個(gè)副產(chǎn)品而被產(chǎn)生出來，目的是用來驅(qū)使渦輪汽輪機(jī)從而滿足發(fā)熱需情都是這個(gè)需求的附屬品，盡管它可能與這個(gè)需求有著極為親熱的聯(lián)系。饋入到鍋爐中以便于匹配蒸汽的產(chǎn)生量。參數(shù)之間都是相互影響和被影響著?！惨粋€(gè)垃圾焚化爐或是一個(gè)供給蒸汽的過程？〕〔是僅需要一個(gè)鍋爐就能夠滿足要求，還是要通過幾個(gè)的結(jié)合？?？傂枨笙到y(tǒng)的性質(zhì)以來與電火電廠；熱電聯(lián)產(chǎn)電廠；垃圾轉(zhuǎn)化為能源的電廠。中的每個(gè)都有自己的需求以及系統(tǒng)要求的參數(shù)。設(shè)定電站應(yīng)用程序的要求一臺(tái)為操作渦旋電站而產(chǎn)生蒸汽的鍋爐應(yīng)當(dāng)確保機(jī)器不停的供電以便于負(fù)1Power-plantControlandInstrumentation-TheControlofBoilersandHRSGSystems；DavidLindsley所不需要的廢熱量。家的需要有關(guān)聯(lián)?！病r(shí)每刻，每天都在轉(zhuǎn)變。這種模型的使用與整個(gè)網(wǎng)絡(luò)都有很大的聯(lián)系，事實(shí)上，大量的發(fā)電機(jī)與用戶之間是通過網(wǎng)絡(luò)來連接并且施加給整體需要的壓力并不大，求。脫鹽工廠〔食用水制造工廠〕作為先決條件。量是由日光燈的水平以及周邊溫度所打算的，這些都會(huì)以穩(wěn)定的模型為根底但所使用也同樣由天氣以及城市的工業(yè)和商業(yè)構(gòu)造所打算。過程中或是整個(gè)地過程中。在美國可以突然上升到2K兆的需求量，這個(gè)需求量等同于一個(gè)一般的大型電廠的總輸出量。美國電網(wǎng)典型電力需求在那里將會(huì)消滅兩個(gè)頂峰期在消費(fèi)模式恢復(fù)正常一小時(shí)左右或是匹配結(jié)果之后。這種形式的需求明顯的是不行預(yù)估的。的限制并且在掌握之下，并且使電廠有效率通常在最經(jīng)濟(jì)的模式下。Pool。這就是下面所要介紹的，由于PoolPool簡(jiǎn)潔的原則為根底。美國Pool個(gè)交易系統(tǒng)的各個(gè)局部響應(yīng)。這個(gè)信息為根底開發(fā)了一個(gè)邊際電價(jià)處理〔SMP〕30分鐘的問題。SMP與一個(gè)能反映發(fā)電廠缺少的測(cè)量值，并且從這些因素可以打算電廠的銷售價(jià)格器的系統(tǒng)規(guī)定參數(shù)等等。然后打算它的操作以確保整個(gè)系統(tǒng)操作的安全以及有效。每個(gè)單元機(jī)組的負(fù)荷安排要同時(shí)以電廠費(fèi)用的消耗以及電廠對(duì)需要變化做出反較快的機(jī)組將很可能承受另一個(gè)價(jià)格比較低廉但是反響對(duì)變化反響較為慢的負(fù)荷。發(fā)電廠應(yīng)用軟件程序的主要需求在一個(gè)單元機(jī)組的發(fā)電站中，鍋爐/渦輪汽輪機(jī)的相應(yīng)是由電廠中兩個(gè)主要的反響慢?！苍谧詣?dòng)化掌握下的各種蒸汽流量范圍力量就強(qiáng)。汽的制造。在這個(gè)章節(jié)中，我們將要分析這個(gè)主要的系統(tǒng)，3、5、6、7的。選擇項(xiàng)。需求信號(hào)可以以渦輪汽輪機(jī)為主〔鍋爐是關(guān)心掌握；也或者以鍋爐為主〔渦輪汽輪機(jī)為關(guān)心掌握；或者同時(shí)執(zhí)行〔系統(tǒng)掌握機(jī)組表現(xiàn)所引發(fā)的結(jié)果，我們將逐個(gè)進(jìn)展分析。鍋爐跟隨操作在這樣一個(gè)系統(tǒng)中，開啟或關(guān)閉閥門的動(dòng)作對(duì)指令的變化供給了期望的相來儲(chǔ)存蒸汽壓力以維持設(shè)定值。SettingthedemandforthesteamgeneratorNatureofthedemandThesteamgeneratedbytheboilermaybeusedtodriveaturbineinathermalpower-plant,oritmaybedeliveredtoanindustrialprocessoradistrict-heatingscheme(oritmaybeprovidedforamixtureoftheseuses).Alternatively,theprimarypurposeoftheplantmaybetoincinerateindustrial,domesticorclinicalwaste,withsteambeinggeneratedasavaluableby-product,todriveaturbo-generatorortomeetaheatingdemand.Ineachcase,thefactorthatprimarilydeterminestheoperationoftheplantistheamountofsteamthatisrequired.Everythingelseissubsidiarytothis,althoughitmaybecloselylinkedtoit.Thedeterminantthatcontrolsalltheboiler”soperationsiscalledthe”masterdemand”.Inthermalpower-plantthesteamisgeneratedbyburningfuel,andthemasterdemandsetstheburnersfiringataratethatiscommensuratewiththesteamproduction.ThisinturnrequirestheFDfanstodeliveradequateairforthecombustionofthefuel.TheairinputrequirestheproductsofcombustiontobeexpelledfromthecombustionchamberbytheIDfans,whosethroughputmustberelatedtothesteamflow.Atthesametime,watermustbefedintotheboilertomatchtheproductionofsteam.Asstatedpreviously,aboilerisacomplex,multivariable,interactiveprocess.Eachoftheaboveparametersaffectsandisaffectedbyalloftheothers.Thewayinwhichthemasterdemandoperatesisdeterminedbothbythegeneralnatureoftheplant(isitapowerstation,anincineratororaproviderofprocesssteam?),andalsobythewayinwhichtheboilerisconfiguredwithinthecontextoftheoverallplant(isthereonlyoneboilermeetingthedemand,orareseveralcombined?).Thenatureofthemasterdemandsystemdependsonthetypeofplantwithinwhichtheboileroperates,anditisthereforenecessarytoexamineitseparatelyforeachtypeofapplication.Inthefollowingsectionsweshalldealwiththemasterdemandasusedinthefollowingclassesofplant:powerstations;combinedheatandpower(CHP)plants;Waste-to-energy(WTE)plants.Weshallseethatalthoughalloftheserequiretheboilertobeoperatedtogeneratesteam,eachhasitsownrequirementsandconstraints.Settingthedemandinpower-stationapplicationsAboilerproducingsteamforanoperatingturbo-generatorhastoensurethatthemachinecontinuallydeliverstherequiredelectricalenergytotheload.Withacombined-cyclegas-turbineplantitisfrequentlythecasethatthepowergeneratedbythegasturbinesisadjustedtomeetthedemand,withthesteamturbinemakinguseofallofthewasteheatfromtheturbines.Withalltypesofpower-generatingplant,however,therequirementforgenerationwillbeset,directlyorindirectly,bythegrid-controlcentre(orthe”centraldispatcher”),andtheamountofpowerthatisgeneratedwillberelatedtothelocalornationaldemandatthattime.Innationalnetworks,powerstationsarelinkedtogethertogenerateelectricalpowerinconcertwithoneanother.Togethertheymustmeetademandthatismadeupofthecombinedneedsof all the usersthat are connectedto the system commercial,agricultural,industrialetc.).Theoveralldemandwillvaryfromminutetominuteanddaytodayinawaythatissystematicorrandom,dictatedbyeconomic,operationalandenvironmentalfactors.Thispatternofuserelatestotheentirenetwork,andthefactthatalargenumberofpowergeneratorsandusersarelinkedviathenetworkhaslittlebearingontheoveralldemand,althoughtheextremepeaksandtroughsmaywellbesmoothedout.Theinterlinkingdoes,however,haveoperationalimplications.Forexample,asuddenfailureofonegeneratingplantwillinstantlythrowanextrademandontheothers.Inacoldortemperateclimatethedemandwillbebasedpredominatelyontheneedforlight,heatandmotivepower.Inwarmerclimatesanddevelopedareasitwillalsobedeterminedbytheuseofair-conditioningand,possibly,desalinationplant(fordrinking-waterproduction).Figure showshowthetotalelectricaldemandontheUnitedKingdom”sGridsystemvariesfromhourtohourthroughtheday,andfromawarmsummerdaytoacoldwinterday.Clearly,inadditiontobeingaffectedbynormalworkingpatterns,thedemandisdeterminedbythelevelofdaylightandtheambienttemperature,bothofwhichfollowbasicsystematicpatternsbutwhichmayalsofluctuateinaverysuddenandunpredictablemanner.Similarprofilescanbedevelopedforeachcountryandwillbe determined by climate as well as the country”s industrial and infrastructure.Thesedays,thedemandforelectricityinadevelopednationisalsoaffectedquitedramaticallybytelevisionbroadcasts.Duringamajorsportingeventsuchasaninternationalfootballmatch,suddenupsurgesindemandwilloccurathalf-timeandfulltime,whenviewersswitchontheirkettles.IntheUKthiscanimposeasuddenriseindemandofasmuchas2GW,whichistheequivalenttothetotaloutputofareasonablylarge.Figure TypicalelectricaldemandintheUnitedKingdomSuchapatternofusagecanbepredictedtowithinafewminutes,andaudiencepredictionsareroutinelyfedtothepower-generationauthoritiesonadailybasistoassistwiththeprovisionofadequatesupplies.Butiftheresultofthematchrequires”extratime”playingtherewillbetwofurtherpeaksbeforethepatternofconsumptionreturnstonormalanhourorsoaftertheendofthematch.This typeofdemandisobviouslynotpredictable.TheGridsystemhastobemanagedsothatthedemandforelectricityismetwithinstatutorylimitsatalltimesandunderallconditions,andtheavailablegeneratingplanthastobeusedinthemosteconomicmanner.SincetheprivatisationoftheelectricitysupplyindustryintheUK,thegenerationofelectricityisbasedonthedemandsofatradingsystemknownasthePool.Thisisbrieflydescribedbelow,becausetheoperationofthePooldetermineshoweachunitreceivesdemandinstructions.Thesubjectisofcriticalimportancebecauseitgovernstheoperationofthepowerplantand,ultimately,itsdemise.AlthoughthefollowingoutlineisbasedontheUKPool,othercountriesusesystemsbasedonsimilarprinciples.OperationoftheUKPoolAt10.eachmorning,Britishgeneratingcompanieswhowishtotradeduringthefollowingdaysubmitbidsonbehalfofeachoftheirplants,accompaniedbyinformationonthecapacityavailablefromeachplantanditsoperationalparameters.Thesebidsarethenrankednationallyinaformofaleaguetable,withthecheapestgeneratoratthetopandthemostexpensiveat thebottom.Thistableistermedthe”meritorder”forallthegeneratingunitsthatarecapableofbeingconnectedtothedetailsofeachday”smeritorderaretransmittedtothebodyresponsibleforoperatingtheGridsystem,theNationalGridControlCentre,andtothebodyresponsibleforthetradingsystems.TheNationalGridControlCentredeterminesanotionalscheduleolthegeneratingplantthatisavailableand,onthebasisofthisinformation,developsasystemmarginalprice(SMP)forevery30-minuteperiodofthedayinquestion.TheSMPiscombinedwithacomponentwhichreflectsthescarcityvaluesofgeneratingplant,andfromthesefactorsisdeterminedthesellingpriceforpower,the”poolsellingprice”.Thistakesintcaccounttheoperationalcostsofthesystem,knownasthe”upliftcosts”.TheupliftincludesfactorssuchasthecostofmaintainingasecuritymarginoJavailablepowerabovethedemand,thecostofancillaryplantthatL,requiredtomaintainvoltageandfrequency,transmissionconstraintsetc.TheNationalGridControlCentreexaminesthesecurityofthetransmissionnetworkthatlinksalltheparticipatinggeneratingplantandconsumers,andthenplansitsoperationstoensurethattheentiresystemoperatessecurelyandefficiently.Attheendofthisprocess,theCentreissuesinstructionstoallpowerstationsconnectedtothenetwork,settingthegenerationdemandfortheir unitsonaminute-by-minutebasis.Itisthesecommandswhichdeterminetheearningsoftheplant,andwithinanygivenplanttheboilerandturbinemustrespondtotheminthemostefficientandreliablemannerpossible.Theloadallocatedtoaunitwillbebasedbothonthecostofgenerationandontheabilityoftheplanttorespond todemandtherightconditions,aunitwhoseoperationalcostsarehighbutwhichrespondsquicklywillbeaslikelytoreceivealoadasonewhichgeneratesverycheaplybutisslowtorespondtochangesindemand.4.3 Themasterdemandinapower-stationapplicationTheresponseofaboiler/turbineunitinapowerstationisdeterminedbythedynamic characteristics of the two major items of plant. These differ quitesignificantlyfromeachother.Theturbine,inverygeneralterms,iscapableofrespondingmorequicklythantheboilertochangesindemand.Theresponseoftheboilerisdeterminedbythethermalinertiaofitssteamandwatercircuitsandbythecharacteristicsofthefuelsystem.Forexample,acoal-burningboiler,withitscomplexfuel-handlingplant,willbemuchslowertorespondtochangesindemandthanagas-firedone.Also,theturndownoftheplant(therangeofsteamflowsoverwhichitwillbecapableofoperatingunderautomaticcontrol)willdependonthetypeoffuelbeingburned,withgas-firedunitsbeinginherentlycapableofoperatingoverawiderdynamicrangethantheircoal-firedequivalents.Thecommonfactorinallthesesystems,however,isthemasterdemandwhich,inadditiontosettingthefiringrate,regulatesthequantityofcombustionairtomatchthefuelinput,andthequantityoffeedwatertomatchthesteamproduction.Inthepresentchapterweshallexaminethemastersystem.Chapters3,5,6and7lookathowthecommandsfromthemastersystemareacteduponbyt