基于超声检测的新型二元混合气体传感器-王飞-吴国贵-和卫星

3812201712PＲOCESSAUTOMATIONINSTＲUMENTATIONVol.38No.12Dec．20172017－07－211992—[e-mail]、[e-mail]212013、。、。TMS320VC5402DSP。A/D。。、。、。1%1．2%。TH7TP212ADOI10．16086/j．cnki．issn1000－0380．201712018NewTypeofBinaryMixedGasSensorBasedonUltrasonicDetectionWANGFeiWUGuoguiHEWeixingSchoolofElectricalandInformationEngineeringJiangsuUniversityZhenjiang212013ChinaAbstractAtpresentthereisaproblemthatthedomesticgasconcentrationandflowsensorhasalowmeasurementaccuracyofthemixedgasconcentrationandflowmeasuring．Tosolvetheproblemsandonthebasisofstudyingthemeasuringprincipleofultrasonicgasflowmeterandanalyzingtheinfluencingfactorsontheconcentrationandflowmeasurementofbinarymixedgasanewtypeschemeofbinarymixedgassensorbasedonultrasonicdetectionisproposed．WithTMS320VC5402DSPasthecontrolchipthehardwaredesignissimplifiedandthedataprocessingabilityisimproved．ThemethodofsignalvalidrangeexaminationisadoptedandbyusinghighprecisionA/DtheultrasonicechosignalisacquiredandPautacriterionistakentoremovethesignalnoise．Azero－crossingdetectionmethodbasedontheenergythresholdisproposedtodetectthezero－crossingpointofultrasonicwaveandcalculatetheultrasonictransmissiontime．Combinedwiththeidealgasstateequationandothertheoriestheconcentrationandflowofbinarymixedgasarecalculatedandanalyzed．Thenewtypeofbinarymixedgassensorandthespecificimplementationschemearegivenandtheexperimentalmeasurementofthebinarymixedgascombiningoxygenandnitrogeniscarriedout．Theexperimentalresultsshowthattheconcentrationerrorislessthan1%andtheflowerrorislessthan1．2%．KeywordsUltrasonicSensorFlowmeterBinarymixedgasDigitalsignalprocessingDSPZero－crossingdetection0。。、、、1。。。。2。。3－4。。38。。1。1。1Ld。A、B4－5。1Fig．1Schematicdiagramofmeasurement1tAB=L珋c+v1tBA=L珋c－v2tABABtBABAv珋c。1．112珋c=LtAB+LtBA23abn1－na、bCpa、CpbCva、CvbMaMbＲT。6An2+Bn+C=04A=MaCva+MbCvb－MaCvb－MbCva珋c2ＲTB=MaCvb+MbCva－2MbCvb珋c2ＲT－Cpa+CpbC=MbCvb珋c2ＲT－Cpb、3。n0≤n≤1。n。1．212v。。。vvi7－8K=vvi5KＲe9－10viLQ=viπd24=tBA－tABLπd28KtABtBA62TITMS320VC5402digitalsignalprocessingDSP2。2Fig．2SchematicdiagramofhardwaredesignDSP。。1。analogtodigitalconverterADCdirectmemoryaccessDMA。DSP/·87·12generalpurposeinputoutputGPIO。311。。3．1。3。3Fig．3Schematicdiagramofeffectivesignalacquisition。70%。70%～80%。。。10。1．4。3．2DSP。12－13。pi=xi－珋x2＞3σxi。。σ14－15σ=S=∑ni=1xi－珋x2n－槡173．316。。4。4Fig．4Base－peakanalysis。4E1、E2、E3、E41。5。5Fig．5Schematicdiagramofzero－crossingdetectionP1P1P2P1P3。P1、P2、P3P0P0。T1P0T2T3T4。T=T1+T2+T3+T4－n×Tf8nTf。4·97·38。。80mm12cm。200kHz。、、。6。6。6Fig．6Figuresoferroranalysis5。、、。DSP。。。。1%、1．2%。。1．J．2001226644－647．2．D．2009．3ALHＲOOBMBATESＲBATTISTINMetal．ImplementationofanultrasonicinstrumentforsimultaneousmixtureandflowanalysisofbinarygassystemsC//InternationalConferenceonAdvancementsinNuclearInstrumentationMeasurementMethodsandTheirApplications20161－9．4．J．20153812100－103．5．DSPD．2014．6．J．2010948－51．7．J．201018122908－2910．8ZHUWJXUKJFANGMetal．MathematicalmodelingofultrasonicgasflowmeterbasedonexperimentaldatainthreestepsJ．IEEETransactionsonInstrumentationandMeasurement20166581726－1738．9．J．201233112422－2428．10．D．2011．11．J．2006324466－470．12ZHENGDMEIJWANGM．Improvementofgasultrasonicflowmetermeasurementnon－linearitybasedonraytracingmethodJ．IetScienceMeasurement＆Technology2016106602－606．13．D．2015．14．J．201223625－28．15PETTEＲNPEＲLMAGNEV．InvestigationofprecisionsoundvelocitymeasurementmethodsasreferenceforultrasonicgasflowmetersJ．IEEEUltrasonicsSymposium200551443－1447．16．J．20074191557－1560．·08·