4電磁理論及磁路

1、WdsExpressionromagismn.電磁，電磁學electricalapparatus電器，電器設備motn.電動機generatn.發(fā)電機fractionaladj.分數(shù)的，幾分之一magicfieldn.磁場couplingdevice連接設備statictransfmer靜態(tài)變壓器electricalpowerdistributioncircuits送變電電路circuitbreakers電路斷路器automaticsw

2、itches自動閘relay繼電器quantityn.變量，數(shù)量magicfluxn.磁通量simplifythecomputations估算AmperesCircuitalLaw安培環(huán)路定律hizontalplane水平面righthrule右手（螺旋）法則fluxdensity磁密度teslan.特斯拉，磁通密度的單位permeabilityn.磁導率，磁導系數(shù)henries亨利（電感單位）henriesmeter亨利米（磁導率的單

3、位）absolutepermeability絕對磁導率relativepermeability相對磁導率Deltamax克鎳鐵磁性合金ferromagicmaterial鐵磁性材料effectivearean.有效面積nmalcomponentn.法線方向分量webern.韋伯，磁通的單位commonflux共有磁通MagicFieldIntensityH磁場強度electricalmachinery電機ampereturnsmeter

4、安培圈米Amperescircuitlaw安培回路定律magomotivefce磁勢magizationcurve磁化曲線demagizationn.退磁residualfluxdensity剩余磁通密度剩磁retentivity記憶力saturation飽和hysteresis磁滯現(xiàn)象hysteresisloop磁滯環(huán)coercivefce矯頑磁力coercivity矯頑力矯頑性magiccircuit磁路maskv.補償cleara

5、ncen.間隙，空隙equivalentcircuit等效電路reluctancen.磁阻examinationn.觀察dimensionn.量綱crosssectionalarea橫截面proptionalto與……成正比inverselyproptionalto與……成反比（4.2）Bisinfactafluxdensityithastheunitsoffluxpersquaremeterteslas.Permeability.It

6、isaacteristicofthesurroundingmediumwhichincreasedecreasethemagicfluxdensityfaspecifiedcurrent.Thepermeabilityofthevacuum(freespace)canbeexpressed70104?????（4.3）Permeabilityisexpressedinunitsofhenrysmeter.Ifthesurrounding

7、mediumisotherthanfreespacetheabsolutepermeabilityisagainreadily?foundfromEq.(4.1).Acomparisonwiththeresultobtainedffreespacethenleadstoaquantitycalledrelativepermeability.Expressedmathematicallywehaver?0????r（4.4）Equatio

8、n(4.4)clearlyindicatesthatrelativepermeabilityissimplyanumericwhichexpressesthedegreetowhichthemagicfluxdensityisincreaseddecreasedoverthatoffreespace.FsomematerialssuchasDeltamaxthevalueofcanexceedonehundredthous.Mostfe

9、rromagicmaterialsr?howeverhavevaluesofinthehundredsofthouss.r?MagicFlux.ItisreasonabletoexpectthatsinceBdenotesmagicfluxdensity?multiplicationbytheeffectiveareathatBperatesshouldyieldthetotalmagicflux.Themagicfluxthrough

10、anysurfaceismerigouslydefinedasthesurfaceintegralofthenmalcomponentofthevectmagicfieldB.Expressedmathematicallywehave??sndAB?（4.5）wheresstsfsurfaceintegralArepresentstheareaofthecoilisthenmalcomponentofBnBtothecoilarea.I

11、thastheunitsofweber.MagicFieldIntensityH.Ofteninmagiccircuitcomputationsitishelpfultowkwithaquantityrepresentingthemagicfieldwhichisindependentofthemediuminwhichthemagicfluxexists.Thisisespeciallytrueinsituationssuchasar