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  • PLC (共7448 份)
  • 用時:20ms
    • 簡介:HEATINGSYSTEMSWITHPLCANDFREQUENCYCONTROLSALAHABDALLAH,RIYADABUMALLOUHDEPARTMENTOFMECHANICALANDINDUSTRIALENGINEERING,APPLIEDSCIENCEUNIVERSITY,AMMAN11931,JORDANARTICLEINFOARTICLEHISTORYAVAILABLEONLINE18JULY2008KEYWORDSHEATTREATMENTPLCCONTROLFREQUENCYCONTROLTEMPERINGABSTRACTINTHISWORK,MEDIUMCAPACITYCONTROLLEDHEATINGSYSTEMISDESIGNEDANDCONSTRUCTEDTHEPROGRAMMINGMETHODOFCONTROLOFHEATINGPROCESSISACHIEVEDBYMEANSOFINTEGRATEDPROGRAMMABLELOGICCONTROLLERPLCANDFREQUENCYINVERTERFITHEPLCMAINFUNCTIONISTODETERMINETHEREQUIREDTEMPERATURESLEVELSANDTHERELATEDTIMEINTERVALSOFTHEHEATINGHOLDTIMEINTHEFURNACEFIISUSEDTOCONTROLTHEDYNAMICCHANGEOFTEMPERATUREBETWEENVARIOUSOPERATINGPOINTSTHEDESIGNEDSYSTEMSHOWSTHECAPABILITYFORFULLCONTROLOFTEMPERATUREFROMZEROTOMAXIMUMFORANYREQUIREDRANGEOFTIMEINCASEOFINCREASINGORDECREASINGTHETEMPERATUREALLVARIABLESOFTHESYSTEMWILLBECHANGEDGRADUALLYUNTILREACHINGTHEIRNEEDEDWORKINGPOINTSANEXPERIMENTALSTUDYWASPERFORMEDTOINVESTIGATETHEEFFECTOFTEMPERINGTEMPERATUREANDTEMPERINGTIMEONHARDNESSANDFATIGUERESISTANCEOF04CARBONSTEELITWASFOUNDTHATINCREASINGTEMPERINGTEMPERATUREABOVE550?CORTEMPERINGTIMEDECREASESTHEHARDNESSOFTHEMATERIALITWASALSOFOUNDTHATTHEREISAMAXIMUMNUMBEROFCYCLESTOWHICHTHESPECIMENCANSURVIVEWHATEVERTHEAPPLIEDLOADWAS?2008ELSEVIERLTDALLRIGHTSRESERVED1INTRODUCTIONHEATTREATMENTISTHECONTROLLEDHEATINGANDCOOLINGOFMETALSTOALTERTHEIRPHYSICALANDMECHANICALPROPERTIESWITHOUTCHANGINGTHEPRODUCTSHAPEHEATTREATMENTISOFTENASSOCIATEDWITHINCREASINGTHESTRENGTHOFMATERIAL,BUTITCANALSOBEUSEDTOALTERCERTAINMANUFACTURABILITYOBJECTIVESSUCHASIMPROVEMACHINING,IMPROVEFORMABILITY,ANDRESTOREDUCTILITYAFTERACOLDWORKINGOPERATIONTHUSITISAVERYENABLINGPROCESSTHATCANNOTONLYHELPOTHERMANUFACTURINGPROCESS,BUTCANALSOIMPROVEPRODUCTPERFORMANCEBYINCREASINGSTRENGTHOROTHERDESIRABLECHARACTERISTICS1,2ANEWSINGLESWITCHPARALLELRESONANTCONVERTERFORINDUCTIONHEATINGWASINTRODUCEDIN3THECIRCUITCONSISTSOFANINPUTLCFILTER,ABRIDGERECTIFIERANDONLYONECONTROLLEDPOWERSWITCHTHESWITCHOPERATESINASOFTCOMMUNICATIONMODEANDSERVESASAHIGHFREQUENCYGENERATORAVOLTAGEFEDRESONANTLCLINVERTERWITHPHASESHIFTCONTROLWASPRESENTEDIN4ITWASSEENTHATTHECONTROLSTRATEGYOFFEREDADVANTAGESINTHEMEGAHERTZOPERATINGREGION,WHEREACONSTANTSWITCHINGFREQUENCYISREQUIREDTHEINVERTERSTEADYSTATEOPERATIONISANALYZEDUSINGFUNDAMENTALFREQUENCYANALYSESACOSTEFFECTIVEHIGHEFFICIENCYINVERTERWITHPHASESHIFTEDPULSEMODULATIONSCHEMEWASPROPOSEDFORMEDIUMPOWER5–30KWINDUCTIONHEATINGAPPLICATIONSISDISCUSSEDIN5THEPROPOSEDINVERTERACCOMPLISHESSOFTSWITCHINGOPERATIONOVERAWIDEPOWERREGULATIONRANGETHEACTUALPOWERCONVERSIONEFFICIENCYREACHEDWAS967ACONTROLMETHODOFREDUCINGTHESIZEOFTHEDCLINKCAPACITORSOFACONVERTER–INVERTERSYSTEMWASPRESENTEDIN6THEMAINIDEAISTOUTILIZETHEINVERTEROPERATIONSTATUSINTHECURRENTCONTROLOFTHECONVERTERTHISCONTROLSTRATEGYISEFFECTIVEINREGULATINGTHEDCVOLTAGELEVELEVENTHEDCLINKCAPACITORISARBITRARILYSMALLANDTHELOADVARIESABRUPTLYIN7AMETHODWASPROPOSEDTOACCURATELYPREDICTTHEMINIMUMREQUIREDTEMPERATURERECOVERYCONSIDERINGREPEATABILITYANDACCURACYOFTHELEAKDETECTORBYINVESTIGATINGTHERELATIONBETWEENTEMPERATURERECOVERYTIMEANDTHEORETICALTHERMALTIMECONSTANTFORVARIOUSTESTVOLUMESANDAPPLIEDPRESSURESUSINGPLCSYSTEMIN8AMETHODOLOGYWASDEMONSTRATEDTODESIGNAPLCPROGRAMTHATORGANIZEDTHERELATIONBETWEENTHEPHYSICALINPUTSANDOUTPUTSOFTHEPUMPINGTOOLSINMANUFACTURINGSYSTEMSIN9ANEXPERIMENTALSTUDYWASPERFORMEDTOINVESTIGATETHEEFFECTOFUSINGTWOAXESTRACKINGWITHPLCCONTROLONTHESOLARENERGYCOLLECTEDTHETWOAXESTRACKINGSURFACESHOWEDBETTERPERFORMANCEWITHANINCREASEINTHECOLLECTEDENERGYUPTO41COMPAREDTOTHEFIXEDSURFACETHEPLCMAINFUNCTIONISTOCONTROLTHEREQUIREDTEMPERATURELEVELSANDTHERELATEDTIMEINTERVALSOFTHEHEATINGHOLDTIMEINTHEFURNACE10FREQUENCYINVERTERISUSEDTOCONTROLTHEDYNAMICCHANGEOFTEMPERATUREBETWEENVARIOUSOPERATINGPOINTS11,1201968904/SEEFRONTMATTER?2008ELSEVIERLTDALLRIGHTSRESERVEDDOI101016/JENCONMAN200711017CORRESPONDINGAUTHORTEL96253740026EMAILADDRESSESSALAHABDALAH_1964YAHOOCOM,SALAHABDALAH_1964HOTMAILCOMSABDALLAH,MALLOUHMAKTOOBCOMRABUMALLOUHENERGYCONVERSIONANDMANAGEMENT4920083356–3361CONTENTSLISTSAVAILABLEATSCIENCEDIRECTENERGYCONVERSIONANDMANAGEMENTJOURNALHOMEPAGEWWWELSEVIERCOM/LOCATE/ENCONMANWHEREEDISTHERECTIFIEDVOLTAGEATTHEOUTPUTOFCONVERTER,RDISTHEACTIVERESISTANCEOFCOILANDIDISTHECOILCURRENT,IUISTHEINPUTCURRENTOFTHEINVERTERANDICTHECURRENTOFTHECONDENSER32MODELINGOFTHEFURNACETHERIGHTHANDSIDEOFFIG2ILLUSTRATESAFURNACECONSISTINGOFATHREEPHASEHEATERINAROOMTHETHREEPHASEHEATEREMITSHEATATARATEOFQ1ANDTHEROOMLOSESHEATATARATEOFQ2Q1?3KH?IUD5TWHEREKHISTHEHEATERCOEFFICIENTASSUMINGTHATTHEAIRINTHEROOMISATAUNIFORMTEMPERATURETANDTHATTHEREISNOHEATSTORAGEINTHEWALLSOFTHEROOM,WECANDERIVEANEQUATIONDESCRIBINGTHETIMERATEOFCHANGEINROOMTEMPERATUREQ1?Q2?CODTDTD6TWHERECOISTHETHERMALCAPACITYOFTHEAIRINTHEROOMIFTHETEMPERATUREINSIDETHEROOMISTANDTHATOUTSIDETHEROOMISTO,THENQ2?T?TOROD7TWHEREROISTHERESISTIVITYOFTHEWALLSSUBSTITUTINGFORQ2GIVESQ1?T?TORO?CODTDTHENCEROCODTDTTT?ROQ1TTOD8T4EXPERIMENTATIONANDRESULTS41TESTINGTHECONTROLSYSTEMPERFORMANCEINORDERTOTESTTHEABILITYOFTHEDESIGNEDCONTROLSYSTEMTOPERFORMTHEDESIREDTEMPERATURECONTROLPROPERLY,SUCCESSIVEHEATTREATMENTEXPERIMENTSWEREPERFORMEDANDTHEIRRESULTSAREDESCRIBEDASFOLLOWSFIG3SHOWSTHEINPUTFREQUENCYVSTIMEANDFIG4SHOWSTHETEMPERATUREVSTIMEFORTHETWOSPECIMENS1AND2WHERETHISPROCESSREPRESENTAHEATTREATMENTPROCESSCARRIEDOUTWITHRAMPINGFUNCTIONONLYIETHEFURNACEANDFREQUENCYINVERTERONLYAREUSED,THEHOLDINGTIMEINTHISCASEWASCOUNTEDOFFFROMTHEMOMENTTHEFURNACEISACTUATEDFORMROOMTEMPERATURETHATISWHYTHEGRAPHSTARTSAT20?CANDTHENTEMPERATURERISEUPUSINGTHERAMPUPFUNCTIONINTHEFREQUENCYINVERTERONARANGEOFTIMEFORPROGRAMCONTROLLERABCV1V4V2V5V3V6V7V8V9V12V11V10CLDCIRUIT1CIRUIT2Q2TTOIDIUICQ1UIUTHREEPHASEHEATERFURNACEFIG2PRINCIPLECIRCUITOFFREQUENCYCONTROLLEDTHREEPHASEHEATERPERSONALCOMPUTERPLCANALOGUNITFREQUENCYINVERTERPARAMETERUNITTHREEPHASEHEATERPROGRAMTOCONTROLTHESLOPEOFTEMPERATURETPROGRAMTOCNTROLTHETEMPERATURELEVELFIG1BLOCKDIAGRAMOFPLCANDFREQUENCYCONTROLLEDHEATINGSYSTEM3358SABDALLAH,RABUMALLOUH/ENERGYCONVERSIONANDMANAGEMENT4920083356–3361
      下載積分: 10 賞幣
      上傳時間:2024-03-13
      頁數(shù): 6
      8人已閱讀
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    • 簡介:2300英文單詞,英文單詞,11500英文字符,中文英文字符,中文3500字文獻出處文獻出處ALIA,ALSOUDM,ABDALLAHEASWATERPUMPINGSYSTEMWITHPLCANDFREQUENCYCONTROLJJORDANJOURNALOFMECHANICALANDINDUSTRIALENGINEERING,2009,3(3)216221WATERPUMPINGSYSTEMWITHPLCANDFREQUENCYCONTROLAKAYLEHALI,MOHAMMEDAL_SOUD,ESSAMABDALLAH,SALAHADDALLAHABSTRACTINTHISSTUDYCONTROLLEDWATERPUMPINGSYSTEMISDESIGNED,CONSTRUCTED,ANDMODELEDTHEPROGRAMMINGMETHODOFCONTROLOFPUMPINGFLOWRATEISACHIEVEDBYMEANSOFINTEGRATEDPROGRAMMABLELOGICCONTROLLERPLCANDFREQUENCYINVERTERFIPLCMAINFUNCTIONISTODETERMINETHEREQUIREDFLOWRATELEVELSANDTHERELATEDTIMEINTERVALSOFTHEFLOWRATEHOLDTIMEFIISUSEDTOCONTROLTHEDYNAMICCHANGEOFTEMPERATUREBETWEENVARIOUSOPERATINGPOINTSTHEDESIGNEDSYSTEMSHOWSTHECAPABILITYFORFULLCONTROLOFPUMPINGFLOWRATEFROMZEROTOMAXIMUMFORANYREQUIREDRANGEOFTIMEINCASEOFINCREASINGORDECREASINGTHEPUMPINGFLOWRATEALLVARIABLESOFTHESYSTEMWILLBECHANGEDGRADUALLYUNTILREACHINGTHEIRNEEDEDWORKINGPOINTSTHEMATHEMATICALMODELOFWATERPUMPINGSYSTEMWITHPLCANDFREQUENCYCONTROLISBUILTBASEDONMATLABSIMULINKATESTRIGBUILTANDANEXPERIMENTALSTUDYWASPERFORMEDFROMTHEANALYSISOFTHEEXPERIMENTALSTARTINGDYNAMICCHARACTERISTICSOFWATERPUMPINGSYSTEMANDMODELEDCHARACTERISTICS,ITWASNOTICEDTHATTHEYAREVERYSIMILARKEYWORDSPLCFREQUENCYCONTROLWATERPUMPINGSYSTEMDYNAMICCHARACTERISTICS1INTRODUCTIONPUMPINGEQUIPMENTSINTHEMODERNMANUFACTURINGSYSTEMSMAYBEUSEDASMAINPARTSINMANYINDUSTRIALACTIVITIES,LIKECHEMICALINDUSTRIES,FOODINDUSTRIES,ETCTHEAUTOMATIONOFTHEPUMPINGPROCESSESINTHOSEINDUSTRIESWILLCERTAINLYLEADTOIMPROVETHEIRPERFORMANCE1INJORDANABOUT18OFGENERATEDELECTRICALPOWERISCONSUMEDBYTHREEPHASEINDUCTIONMOTORSDRIVENCENTRIFUGALPUMPINWATERPUMPINGSTATIONSFROMTHEANALYSISOFTHEWORKINGCONDITIONSOFWATERPUMPINGSYSTEMS,ITISNOTICEDTHATTHEREAREMANYPROBLEMS,WHICHFACETHEWORKOFSUCHSYSTEMS,ASHYDRAULICHAMMERS,DYNAMICSTRESSESINMECHANICALPARTS,HIGHSTARTINGCURRENTSINTHETHEREPHASEMOTORDRIVENCENTRIFUGALPUMP,ANDENERGYSAVINGPROBLEMS2ANEWSINGLESWITCHPARALLELRESONANTCONVERTERFORINDUCTIONHEATINGWASINTRODUCEDIN3THECIRCUITCONSISTSOFANINPUTLCFILTER,ABRIDGERECTIFIER,ANDONLYONECONTROLLEDPOWERSWITCHTHESWITCHOPERATESINASOFTCOMMUNICATIONMODEANDSERVESASAHIGHFREQUENCYGENERATORAVOLTAGEFEDRESONANTLCLINVERTERWITHPHASESHIFTCONTROLWASPRESENTEDIN4ITWASOBSERVEDTHATTHECONTROLSTRATEGYOFFEREDADVANTAGESINTHEMEGAHERTZOPERATINGREGION,WHEREACONSTANTSWITCHINGFREQUENCYISREQUIREDTHEINVERTERSTEADYSTATEOPERATIONISANALYZEDUSINGFUNDAMENTALFREQUENCYANALYSESACOSTEFFECTIVEHIGHEFFICIENCYINVERTERWITHPHASE–SHIFTEDPULSEMODULATIONSCHEMEWASPROPOSEDFORMEDIUMPOWER530KWINDUCTIONHEATINGAPPLICATIONSISDISCUSSEDIN5THEPROPOSEDINVERTERACCOMPLISHESSOFTSWITCHINGOPERATIONOVERAWIDEPOWERREGULATIONRANGETHEACTUALPOWERCONVERSIONEFFICIENCYREACHEDWAS967ACONTROLMETHODOFREDUCINGTHESIZEOFTHEDCLINKCAPACITORSOFACONVERTERINVERTERSYSTEMWASPRESENTEDIN6THEMAINIDEAISTOUTILIZETHEINVERTEROPERATIONSTATUSINTHECURRENTCONTROLOFTHECONVERTERTHISCONTROLSTRATEGYISEFFECTIVEINREGULATINGTHEDCVOLTAGELEVELSPEED2900RPMPCONNECTSTHEUPPERANDLOWERTANKSWITH05INCHSTEELPIPESTOPROVIDEANUNLIMITEDWATERSUPPLYFORTHESYSTEMTVISATHROTTLINGVALUEWHICHCOULDBEUSEDFORVARYINGTHEFLOWRATEMANUALLYAVENTUREMETERWASUSEDTOMEASUREWATERFLOWRATE,ANDASTOPWATCHWASUSEDTOMEASURETHETIMETHEROTATIONALSPEEDOFTHEPUMPIMPELLERWASCALCULATEDUSINGTHEFOLLOWINGPROPORTIONALITYEQUATIONQA/QRNA/NR1WHEREQATHEACTUALFLOWRATEOFWATERQRTHERATEDFLOWRATEOFWATERNATHEACTUALSPEEDOFMOTORNRTHERATENSPEEDOFMOTORTOINVESTIGATETHESYSTEMPERFORMANCEDURINGSTARTINGTOWARDSDIFFERENTINPUTSIGNALS,THEFREQUENCYCONTROLLAWSWHICHREPRESENTTHEFREQUENCYFUNCTIONOFTIME,SHOWNINFIGURE2,WEREUSEDTHECONTROLLAWSWERESTARTEDFROMTHEBASEFREQUENCYOF10HZTHROUGHTHESTARTINGTIMETOREACHREFERENCEFREQUENCYOF50HZINCASEOFDIRECTCONNECTIONTOTHESUPPLYNETWORK,THESTARTINGTIMEEQUALSZEROASSHOWNINCURVE1OFFIGURE2,WHICHREPRESENTSSTEPSIGNAL11FIGURE2THEPROGRAMMEDINPUTFREQUENCYOFTIMEINCASEOFSTARTINGTHECURVES2,3AND4INFIGURE2,WHEREOBTAINEDBYUSINGDIFFERENTRAMPSIGNALSWITHSTARTINGTIMEEQUALTO2SECONDS,3SECONDS,AND4SECONDSRESPECTIVELYACCORDINGTOTHEDIFFERENTINSERTEDCONTROLLAWS,THEOUTPUTFLOWRATEOFTHEWATERPUMPINGSYSTEMINSTARTINGCONDITIONCHANGEASATIMEFUNCTIONASSHOWNINFIGURE3FIGURE3FLOWRATEVSTIMEACCORDINGTOTHEDIFFERENTINSERTEDCONTROLLAWS
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      上傳時間:2024-03-12
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