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1、英文翻译系别专业班级学生姓名学号指导教师TheprincipleoftoroidalcoildetectionToroidalcoillengthis2m,widthdependsonthelanewidth,usuallycoveringalaneof50%~60%,shouldnotbelessthan0.5m.Knowbyelectromagneticfieldtheory,anycurrent-carryingconductorwillbeproducedinthesurroundingmagneticfield,forthelengthofltype,numberoft
2、urnsfortheNofsolenoidcoil,coilinthemagneticfieldstrength.Theselfinductanceis:L=LSL0N2Al(1)Type:therelativepermeabilityofLSismedium,airLSto1;L0=4x10-7hm-1;A.tocoilaroundthearea.Becauseoftoroidalcoilcannotcompletelyequaltosolenoid,consideringthenonuniform 1.Designprincipleandthehardwareofthesys
3、temThesystemdesignprincipleandhardwaresystemdesignprincipleasshowninfigure1.Toroidalcoilthroughfeederconnectiontotheisolationtransformer,ontheothersideoftheisolationtransformerandacapacitanceinparallel,LCparallelresonanceofthisLCparallelresonantfrequencycanbeobtainedaccordingtotheformula(1)[1
4、].F=12PLC(1):L)))forthecircularcoilandthetotalinductanceoffeeder;C)))forparallelcapacitor;F)))astheresonancefrequency.Canbeseenbytheformula,thefactorsinfluencingthefrequencyfonlyLandC,soincertaincases,Cringcoilandthetotalinductanceoffeederdeterminesthefrequencyofoscillation.Thenumericalvalues
5、ofsimilarproductsathomeandabroadforreference,atthesametime,todeterminethevehicledetectorcoiloscillationfrequencyisbetween20~100KHZrange.Circularcoilinductanceis80~120lh,feederinductancefor019H#m-1,plustheinfluenceofotherfactors,thelengthofthefeederinwithin300m,inordertomakethetotalinductancei
6、slessthan1000lh.Isolationtransformerprimarycoilandsecondarycoilnumberofturnsforthe1b1,itmakesthetotalinductancecoilandfeedertruthfullyfromprimaryreflectiontothesecondary,isolationeffect,preventdamageofexternalinterferenceoftheinternalcircuit.Diagram1.thesystemprincipledesignofschematicdiagram
7、Inthedesignofthephase-lockedloopcircuitcomposedofMM74HC4046MroleistoprovideacurrentsourceforLCoscillation,itsfrequencylockingrangebetween20to100kHz.Phase-lockedloopismainlycomposedofthephasecomparator,voltage-controlledoscillator,lowpassfilte
