梯形波勵電磁流量計的研究與設計.pdf

1、河北工業(yè)大學碩士學位論文梯形波勵電磁流量計的研究與設計姓名：賈敬朝申請學位級別：碩士專業(yè)：電工理論與新技術指導教師：劉福貴20061201梯形波勵磁電磁流量計轉換器的研究與設計IIRESEARCHDESIGNOFELECTROMAGICFLOWMETEREXCITEDBYTRAPEZOIDALWAVEABSTRACTElectromagicflowmeterwhichisakindofinstrumentfmeasuringthevol

2、umefluxofelectricliquidarecomposedofelectromagicflowsenssignalconversionpartcomputationpart.Itcanbewidelyusedinmanyfieldssuchasconcretechemicalengineeringtextileindustrymetallurgymineindustrypapermakingmedicamentbrewages

3、oonespeciallyinenvironmentalprotection.Inelectromagicflowmeterthewkingmagicfieldofthesensisgeneratedbyexcitationsystem.Theexcitationmodedecidestheacterofsens’swkingmagicfieldelectromagicflowmeter’santijammingabilitytheca

4、pabilitytokeepstability.Excitationtechnologyisalwaysanimptantdirectiongtostudy.Innowdaysmanycompaniestakelowfrequencerectangularwaveastheirmainexcitationmode.Thoughthiskindofexcitationmodecangetoverdirectcurrentpolarizin

5、gvoltageasaresultofrectangularwaveexcitationexistslevelsuddenchangeeffectofdifferentialinterferenceinphaseinterferenceareintroduced.TheSNRofsens’soutputsignalobviouslyreducedinmeasuringlowvelocityofflow.Thiscausebadzerop

6、ointstabilitybadmeasuringveracity.Inthispaperthepivotaltechnicalprobleminthedesignofelectromagicflowmeterisfirstanalyzed.Theiginofdifferentialdisturbanceinphasedisturbancearediscussed.Inthedesignofintelligentelectromagic

7、elowmetertrapezifmwaveexcitationmethodisintroduced.ItreducesdBdtminishestheinfluenceofdifferentialdisturbanceinphasedisturbance.SCMDAchiparecombinedtoproducetrapezoidalwave.Withsoftwarecontrolthem.thefrequenceoftrapezoid

8、alwavecanbemodulated.Insignalprocessingpartpretreatmentcircuitmagnifyingcircuitfiltercircuitwillbedesignedhowsignalsisprocessedwillbeanalyzed.Thepaperdemonstratesthefeasibilitytousetrapezoidalwavetoexcitatedelectromagicf