本科畢業(yè)論文（設(shè)計）相關(guān)中英文翻譯資料資料題目：頻譜分析在轉(zhuǎn)子動平衡中的應(yīng)用學(xué)生姓名：所在院系：機(jī)電學(xué)院所學(xué)專業(yè)：機(jī)電技術(shù)教育指導(dǎo)老師：APPLICATIONOFFREQUENCYSPECTRUMANALYSISINTHEROTATORMOVINGEQUILIBRIUMABSTRACTTheexperimentalequipmentisdevelopedtosimulatetherotatorvibration.Therunningstateofmachineissimulatedbyusingdifferentrunningconditions.Thevibrationcausedbynon-equilibriummassisanalyzedanddiscussedforfirstorderwithfocusload.Theeffectivemethodisfoundoutbyusingfrequencyspectrumanalysis.INTRODUCTIONIntheconventionalislandofnuclearpowerplant,turbinegeneratorsetisaveryimportantequipmentinwhichthecorethermalenergyistransferredintoelectricenergy.Whentheturbinegeneratorsethasrunforlongtime,theoriginalequilibriumofsystemwouldbeupsetbecauseoftheremnantdeformedofthemetal,abrasionordamagingofthecomponentsetc.Asaresult,thevibrationwillbeincreased.Soitisnecessarytoadjusttheequilibriumatspot.Ontheotherhand,alargeturbinegeneratorsetalsoneedstheworkforadjustingtheequilibriumintheprocessofmanufacture,debugging,installationandoperation.Themovingequilibriumtechniqueatspotisanimportantmeanstoeliminatetheviolentvibrationoftheturbinegeneratorset.Wecouldhaveadefinitelyviewforthevibrationtype,vibrationpowersourceandvibrationpropertybyanalyzingthevibrationoftheturbinegeneratorsetordoingsomespecialexperiment.Whenthevibrationsignalisobtained,thefrequencyspectrumcouldbeusedtoanalysisthevibrationsignalinordertodiagnosequickly.Usingfrequencyspectrumanalysis,theelectricalsignalofvibrationthatisobtainedbythevibrationsensorandhasawidefrequencyrangewillbedecomposedintoseveralmainfrequencycompositions.Differentfrequencycompositionshavedifferentinfluenceontheturbinegeneratorset.Thefrequencyspectrumanalysisisaveryusefulmethodtostudythevibrationofturbinegeneratorset.Thevibrationcausedbyrotatormassnon-equilibriumwithconcentratedloadisdiscussedandanalyzedinthispaper.Andaneffectivemethodtopreventthevibrationispresentedbyusingfrequencyspectrumanalysis.1EXPERIMENTALEQUIPMENTTheexperimentalsystemconsistsofthemotor,shaftcouplingandrotoretc.Itsstructureisverysimple.Therotorisdrivenbythemotordirectly.Itsrotatingspeedcouldbeadjustedinawiderange.Thesystemcouldbeoperatedsmoothlyandreliably.Theratedcurrentofthemotoris2.5A,theoutputpoweris250W.Thefieldexcitationofthemotorisprovidedbythe220VACpowersourcewhichiscommutatedbythespeedregulator,thearmaturecurrentofthemotorisalsoprovidedbythesamepowersource.Itisadjustedbythecompressorgovernor.Throughadjustingtheoutputvoltageofcompressorgovernor,themotorcouldbeofstep-lessspeedregulatedattherange010000r/min,therateofvelocityincreasingcouldbe800r/min.Thelengthoftheexperimentalequipmentis1200mm,thewidthis108mm,themassisabout45kg,thediameteroftheshaftis9.5mm,thelengthoftheshaftis500mmandthemaximumdeflectionislessthan0.0050.015mm.Anypositionalongtheaxialdirectioncouldbeselectedasexperimentalabutmentpoint.Thediameterandmassoftheexperimentalrotatingtableis7619mmand600g,respectively.ThearrangementofexperimentalequipmentisshowninFig.1.Fig.1ThearrangementofexperimentalequipmentTheelectricalvortexsensorsareusedtomeasuretherelativelydisplacementorvibrationforaxistobearingpedestal.Theyareinstalledinthexandydirectionsatthesensorsupport,respectively.Theydonottouchtheshaft,andcouldbeusedtodirectlymeasurethevibrationsignaloftherotationshaft.Theflashingphase-measurerisusedtomeasuretherotatorspeedandthephaseoftheshaft.2THEFREQUENCYSPECTRUMANALYSISOFVIBRATIONSIGNALTherealvibrationofturbinegeneratorsetisthemostofsimpleharmonicperiodicmotion.Itswavetypeisalsomadeofmanysimpleharmonicmotion.Inordertoanalysisthevibration,weshouldstudythewavetype,thefrequencycompositionofthevibration,andtheamplitudes.Frequencycanbeusedasx-axistodescribethevibrationinthefrequency-domain.Themethoddecomposingthevibrationintoitsvariousfrequencycomponentsinfrequencycomponentsinthefrequencydomainiscalledfrequencyspectrumanalysis.Thepurposeoffrequencyspectrumanalysisistodecomposethesignalsintodifferentcompositions.Sothevibrationbecomesthesimpleharmonicmotionincludingdifferentamplitudes,frequenciesandphases.Inthefrequencyspectrumofrotatorvibration,thedifferentfrequencyisoftencorrespondingtothedifferentreason.Ifwecanfindthefrequencycompositionofthevibrationsignal,thereasonofvibrationwillbediscovered.Thereareabout80%accidentscausedbyrotatornon-equilibriuminthevibrationaccidentsofturbinegeneratorsethappenedinthespot,and90%accidentscausedbyrotatormassnon-equilibrium.Intheexperimentsdescribedinthispaperwestudythevibrationcausedbyrotatormassnon-equilibriumbyusingthemethodoffrequencyspectrumanalysisandtheinfluencecoefficientmethodoffindingequilibriumtodeterminethepositionofrotatormassnon-equilibrium.3EXPERIMENTALRESULTSANDANALYSISTheBodediagramshownasFig.2isaboutthehorizontalvibrationcharacteristicsofrotator.Itshowsthatthecriticalvelocityofrotatorisabout2605r/min,themaximumamplitudeofrotatorcorrespondingtothebearingshellis371m,theamplitudeofselectfrequency(AMP-1X)is360m,andthephasedifference(PHA-1X)is-36.ThemarkpositioninFig.3isthemaximumvalueofvibration,andalsoisthepositionwhe