对煤矿矿井提升机钢丝绳损毁的钢丝检测装置研究外文文献翻译中英文翻译Word下载.docx

对煤矿矿井提升机钢丝绳损毁的钢丝检测装置研究外文文献翻译中英文翻译Word下载.docx

《对煤矿矿井提升机钢丝绳损毁的钢丝检测装置研究外文文献翻译中英文翻译Word下载.docx》由会员分享，可在线阅读，更多相关《对煤矿矿井提升机钢丝绳损毁的钢丝检测装置研究外文文献翻译中英文翻译Word下载.docx（11页珍藏版）》请在冰点文库上搜索。

WANGHong-yao1,HUAGang1,TIANJie2

1SchoolofInformationandElectricalEngineering,ChinaUniversityofMining&

Technology,Xuzhou,Jiangsu221008,China

2SchoolofMechanicalElectronicandInformationEngineering,ChinaUniversityofMining&

Technology,Beijing100083,China

Abstract:

Inordertoovercometheflawsofpresentdomesticdevicesfordetectingfaultywiressuchaslowprecision,lowsensitivityandinstability,anewinstrumentfordetectingandprocessingthesignaloffluxleakagecausedbybrokenwiresofcoalmine-hoistcablesisinvestigated.Theprincipleofstrongmagneticdetectionwasadoptedintheequipment.Wiresweremagnetizedbyapre-magneticheadtoreachmagnetizationsaturation.Ourspecialfeatureisthatthenumberofflux-gatesinstalledalongthecircledirectiononthewallofsensorsistwiceaslargeasthenumberofstrandsinthewirecable.Neighboringcomponentsareconnectedinseriesandtheinterferenceonthesurfaceofthewirecable,producedbyleakagefromthefluxfieldofthewirestrands,isefficientlyfiltered.Thesampledsignalsequenceproducedbybrokenwires,whichischaracterizedbyathree-dimensionaldistributionoftheflux-leakagefieldonthesurfaceofthewirecable,canbedimensionallycondensedandcharacteristicallyextracted.AmodelofaBPneuralnetworkisbuiltandthealgorithmoftheBPneuralnetworkisthenusedtoidentifythenumberofbrokenwiresquantitatively.Inourresearch,weuseda6×

37+FC,24mmwirecableasourtestobject.Randomlyseveralwireswereartificiallybrokenanddamagedtodifferentdegrees.Theexperimentswerecarriedout100timestoobtaindatafor100groupsfromoursamples.ThedatawerethenenteredintotheBPneuralnetworkandtrained.Thenetworkwasthenusedtoidentifyatotal16wires,brokenatfivedifferentlocations.Thetestdataprovesthatournewdevicecanenhancetheprecisionindetectingbrokenanddamagedwires.

Keywords:

wirecable;

brokenwire;

signalprocessing;

detectiondevice

CLCnumber:

TB42

1Introduction

Itiswell-knownthatcoalmine-hoistcablesareanimportantpartincoalmine-hoistsortransportationsystems.Wiresare,infact,subjectedtobreakageduetowear,corrosionandfatigue.Theextentofdamageandthecarryingcapacityofwiresaredirectlyrelatedtothesafetyofequipmentandstaff.Atpresent,therearemanydetectiondevicesforbrokensteelcablesmanufacturedinChina,butmostdevicesdonotmeettheconditionsideallyrequiredinpractice.Thereasonsarelargelythecomplexstructureofwires,badworkingconditions,themultiplicityanduncertaintyofbrokenwires.Itisthereforequitedifficulttodetectsignsofbrokenwiresaswellastoanalyzeandprocessdetectedsignalofbrokenwiresincables[1].Anewinstrumentforbrokenwiresdetectionandprocessionofcoalmine-hoistcableswasinvestigatedforthispaper.Withthespecialstructureofadetectiontransducer,theinterferingsignalfromtheleakagefieldofwiretwistscanbefilteredefficiently.Aftertheextractionofdimensionalcontractionandcharacteristicvaluesofmulti-wayssignals,aquantitativeBPneuralnetworkrecognitionforbrokenwiresinsteelcableswasrealized.Thetestresultsarepresented.

2BasicStructuralPrincipleoftheOn-LineDetectionInstrumentforCoalMine-HoistCable

Thestructuralprincipleoftheon-linedetectiondeviceforwirecablesstudiedbyusisshowninFig.1.Thedetectiontransduceriscomposedoftwosemicirclecylindricalstructureswhichcanbeopenedorclosed.Themagneticsensingunitisafluxgateunitmadeofasinglemagneticcoreandissingle-winding.Somemagneticsensingunitsareevenlyarrangedaroundtheinnerwallofthetransducer,thenumberofwhichistwiceasmanyasthenumberofthewirestrandsintheinspectedcable.Aswell,twoneighboringunitsareconnectedinseriestoadetectionchannel.Consequently,thenumberofdetectionchannelsofthedetectioninstrumentisequaltothenumberofwirestrandsinthecable.

Fig.1Structuralprincipleofdetectioninstrument

forbrokenwiresincoalmine-hoistcables.

Afterbeingfilteredandreshaped,thedetectionsignalfromeachchannelissenttothesignalprocessingunit.Theanalogdetectionsignalisconvertedintoadiscretedimensionalsequenceofsamplingvaluesbymulti-channelA/Dconversion,followedbyacharacteristicextraction,aBPneuralnetworkrecognitionandtheoutputoftheresult.Whenviewedseparately,theleakagefieldsignaldetectedbyeachsinglefluxgateunitistheleakagefieldintensityinthesteelcablewherethecorrespondingfluxgateunitsarelocated.Thatis,theoutputsignalZjkofanyjthtestunitis:

WhereFCisthestructuralparameterofthefluxgate,thewidthofthedrivesquare-wave,s􀈝

thesaturatedmagneto-conductivityrate,Bc,jthemagnetic

inductionintensityoftheleakagefieldproducedbybrokenwires,Br,jthemagneticinductionintensityoftheleakagefieldproducedbywirecabletwists,ZfjthesignalvalueofbrokenwiresandZr,jthevalueoftheinterferencesignalproducedbywirecabletwists.

After,FC，a,us,Fareassured,F􀁅

isaconstant.Afterthewirecablesaredeeplymagnetized,thenumericalvalueofs􀁐

isverysmall.Asaresult,thevalueofc,jislargerandthereisnoneedtomagnifyandprocessthedetectionsignalagain.Whenthesensorisoperatingalongwirecablesataspecifiedspeed,thesignalsdetectedbyeachofthemagneticfluxgateunitscaneffectivelyshowthethree-dimensionaldistributionstatusofmagneticfluxleakage,generatedatthesurfaceofwirecables[2–4].

3FiltrationoftheWavelikeOscillationInterferenceSignalProducedbyCableWireTwists

Thesignalofbrokenwiresfromwirecablesobtainedbyasinglefluxgatedetectionunitofthetransducer（formula

（1））containsallkindsofinterferingsignals.TheeffectofthewavelikeoscillationmagneticfluxleakageBr,jduetothespecialstructureofthesteelcablesislargest,whichdirectlyaffectsthedetectionofbrokenordamagedwires,especiallyincoalmine-hoistcables.Weshouldconsiderthepossibilityoffilteringtheinterferencesignals.Informula

（1）,theinterferencesignalr,jcausedbyawavelikeoscillationshowsupasperiodicvariation.Thiskindofwavelikeoscillationinterferencesignalcanberegardedapproximatelyasasinewave,asshowninFig.2.

Fig.2Wavelikeoscillationinterferencesignal

producedbythecabletwist

Overthelengthdirectionofwirecables,itsvariationperiodTisaLaylengthofcablewirestrands.Atthecircledirectionofthewirecable,itsvariationperiodisthereciprocalofthenumberofouterwirestrandsofthecirclelengthofthewirecable.Therefore,thewavelikeoscillationinterferencesignalofthejthdetectionchannelcanbeexpressedas:

j

WhereaistheDirectCurrentComponentofthewavelikeoscillationsignal,mtheAlternatingCurrentComponentmagnitudeofthewavelikeoscillartionsignal,Trepresentsthevalueofperiods,yisthepositionofthedetectionunit,startingfromtheinitialspot,j􀁍

theinitialphaseofthewavelikeoscillationsignal,Nthenumberofwirestrandsofthesteelcable,andisthenumberofdetectionunits.cObviouslywhenc,i.e.,whenthenumberofdetectionunitsdoublesthenumberofouterstrandsofthewirecable,thewavelikeoscillationsignalcontainedintheleakagemagneticfieldsignalinspectedbyanytwoneighboringdetectionunitsisinareversalphase.Therefore,whentheneighboringdetectionunitsalongtheinnerwallofthecylinderofthetransducerstructureareconnectedforwardintoatestchannelinseriestwobytwo,itisequivalenttoaddingthe（j+1）thtestchannelsignaltothejthtestchannelsignal.Thusthestrandpeakvalueofthewavelikeoscillationsignalcompensatesforthestrandvalueforthemoment.Thatis,atthismoment,theonlyremainingwavelikeoscillationsignalistheDirectCurrentComponen

Atthismoment,themagneticfieldsignalofleakagefromanyoftheinspectionchannelsmadeupofthefluxgatearrayshouldbe:

ofthisformulacanbeeliminatedwhenthezerodetectionpositionisadjusted.Therefore,weconsideredthatthewavelikeoscillationinterferencesignalofcablewiresisfilteredbyformula（4）.Afterthispretreatment,eachleakagefrombrokenwires,shownbymagneticfieldsignalsfromthetransducer,becomesachannelsamplevaluebyA/Dconversion,asshowninFig.3.

Fig.3Multi-channelsamplingvalueofbrokenwire

signalsfromwirecables

4ExtractionofCharacteristicValueofSignalsfromBrokenWires

AsisshowninFig.3,theN-channelinspectionsignalsfromthetransducerbecomesitssamplingsequencebyA/Dconversion.IfthenumberofsamplesofthesignalsofbrokenwiresisK,thesequenceofbrokenwiresamplesignalsofthejthchannelcanbeexpressedasarowvectorwithKelements.

TheN-channelsignalsequencewillmakeupaN-dimensionalseriesvectorgroupofbrokenwiresignals:

Atthismoment,Zisacharacteristicmatrixofbrokenwiresanditcontainsalltheinformationonthestatusofthebrokenwires.N􀁵

KGiventheanalysisofrepeatedexperiments,thewidthofthediffusedleakagefromthemagneticfieldonthesurfaceofwirecablescreatedbybrokenwiresisnotlargerthan20mm.Whenthespeedoftheinspectedwirecableis3m/sandthesamplingintervalis1.2mm,thenumberofsamplesKis16atmost.WhenthenumberofinspectionchannelsisN=4,Zshouldbea4×

16matrix.IftheanalysisofthecharacteristicmatrixofbrokenordamagedwiresZweredirectlycarriedou