Table Of ContentSoft Ferrites
Properties and Applications
E. C. Snelling
SofFte rrites
)
SoftF errites
PorperatniAdep sp lications
E.C.S nellBi.nS(Egcn,.g) ,.C .EnFg..1,. E.E.
MullaRredsse aLracbho ratories
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59022 729 0
Contents
Preface
Acknowledgements
1 FerrtihteeNisar;t uPrree,p araantPdir oonc essing 1
2 ThEex preosfEs lieocnt arniMdca agln ePtriocp erties 18
3 Propeorfst oimeMesa ngaZniensacenN di cZkielnF ce rrites 38
4 MagneCtiirccT uhieto ry 171
5 Inductors 193
6 HigFhr equTernacnys ductors 225
7 WidBea nTdr ansformers 237
8 PulTsrea nsformers 269
9 PowTerra nsformers 297
10F errAinttee nnas 327
11P ropeorfWt iinedsi ngs 337
AppenAd Wiixr Tea bles 359
AppenBd iCxa lculoaftt hCieoo rnFe a ctoofarP so Cto re 377
AppenCd iSxy mbols 379
Index 385
Preface
Ferrhiatvbeees c ofimrem elsyt abalsio snohefe t dhm eo sitm porctlaansotsfp e rse sdeanmyta gnetic
matearniadar lwesi duesleiydnl indeiagrai,nt mdai lc robwraavneoc feh leesc etnrgiicnaelOe ftr hiensge.
applictahtoiisntoe hn dsei, g aintmdai lc rofiwealvaderrs ea twheeslrel r bvyet dhl ei terwahteuriretea ,s
appears tthhaethr aebhs ei etnnhot e erxttosb poeocki dfiecvaolttlotey hdp e r opearntadip epsl ications
oft hlea ragnemdso ts ets tabglriosouhffepe r dr iit.teehs.o, hs aev ihniggp he rmeaabnildlo liwot sys es.
Iitts o r emetdhydi esfi citehntachtybi oso hka bse ewnr itIttiecs no .n cewrinttehhdt e e chniimcally
portant opfmr aogpneerttsiiocfefaestlr lrayitfr t eeqsu eunpct ioae bso1 u0tM0 H za,n tdh aep plications
oft hefesrer ittoie nsd ucttroarnss,fo arnmrdee rlsad teevdiI ctie sps r.i mairnitleyfon rde elde ctrical
enginaenpedhr yss iwchiowssoters ik n vodlevseoisrgd ne veloupsmitenhngetf s eer rTihtuteshst e.r eat
menotfe acahs poeftc htse u bjiedsci tra encfudtn ctiBounitait lns .o s tu perafidceiqadulea;tt aaeni dl
analiysgs iivswe hne irite sr eletvota hnmeta ipnu rpDoasteta.h, e orreetliactaainlodd ne ss,oi grn
selepcrtoicoenhd auvree sgb ieveienntn h meo satc cesasniudbs leefu l Wfohremrsep.vo esrs tihbel e
laboofud re soirgs ne lehcatbsie oemnni nimbiytz hecedo mputoaftt hifeou nn ctiinovnoasln vtdeh de
presenotfta htreie osinun tl atbsu olrga rra phfoircma.l
Thfoeu ro pencihnagp dteeawrlis tt hhp er opeorffet rireiastn emdsa gnectiircci ungi etnseT rhael .
firgsitv aeb sr oiandt rodtuofc etrimroaintt eer ainaadql usa lidteastcirvoiefpt thoiero inog fit nh e
magnpertoipce Irattl idseeoss .c ribaessp eotcfmht aosns uefa catnupdrr eo cetshsmaiatnby ge o fi nterest
tot hues eTrh.ne e xcth apctoenrs iidnde erttsah ieelx preosfts hieeol ne catnrmdia cganlpe rtoipce rties
offe rrirtaensgfr ionmtg h Rea ylreeilgahtt ori eocnresen cto mmenodfta htIein otnesr nEalteicotnraol
techCnoimcmails sion.
Chap3ti edsre vottoaew di de-rsaunrgovifetn yhgp e r opeorfct uirersae vnatilmlyaa nbglaezn iensce
anndi czkiefenlrc r iItstet saw.ri ttasth a buloafat ltilhof ene rmraintuefa ctkunroewtrnots ha eu thor;
enteargeadie nascmtha nufacatruterhc eeur r rmeantteg rriaandlue m bcelrass ascicfioerdtd oai pnpgl ica
tioTnh.efo rlel oawnes x tepnrseisveen otfma attieoprnri oaple crotniteaosiv ne1ir8ns 0ge pagrraatpeh s.
Int hcea soefM ullFaerrdr oxtchdueab tweae rlea rggeelnye rbaytt heaedu thaonrhd i cso lleagues
whertehaoest hdeartw ae reex clussuipvpebllyity eh mdea nufactcuornecreEsrv neeerdffy.o h ratbs e en
madteoe nstuhrtaeht se e leicastsc i oomnp rehaenrndes pirvees aespn otsastTiihbvaeleu e t.eh xoprr esses
higsr attiott uhmdeae n mya nufactwuhrohe arvcseo ntrdiabtutatot e hsdie sc tainhoden a polofogri ses
anoym issoiruo nnbsa ltahnamctae yb ecoampep arTehnefot u.r tchh apctoenrs itdhreeer lsa tions
betwtehepenr opearnttdih geees o meotftr hpyer acmtaigcnacelit ricceu .tight.ee, ff eocfnt o n-uniform
crossesc taiigoran p,es t,c .
Thnee sxtic xh apetaecdrhes wa ilt abh a stiycpo effe rrited-ecvoiIrcnoee rd.d t eopr r event repetition
anedx cepsrsoilvief tehraeai thmia bosen et not retahfteu ndampernitnacilin sp olmdeees t aanitdlo
avociodn sidoefrt ahmteoi rosenp ecviefircs oifto hnes deviicmep.o raTtphapunltsi csautcaihso ns
telephonceo iIll.ostFa,r.d a innsgfo Tr.mVle.iro nsue,t put treatnchsa.fov,nre omb tee ressne, p arately
descrbiubiten da,s maustc hhed iers iicsgo nn cewrintfeehrd r ciotrete hsee s seinntfoiramlaw tiibloeln
founidnt hecshea ptTehrecsyo. n siintd uerirn n ducttroarnss,d wuicdbteao nrtdsr ,a nsfoprumlesres ,
transfopromweterrrsa ,n sfoarnmmdea rgsn etic Eaancithase nsntoauftsd h.bye a stihce aonrddye sign
concweiptsthps e crieafelr teonc coerp er opearntgdie eosm eTthreycs.he a pctoenrtsma uicsnhp ecially
compudtaetadan o dr igwionrakl.
Finaalltllhyd e e saisgpne tchtraset l paatret ictuotl hwaeir nldyai nnadgr ceo mmtoonan umboefr
thaep plicea.trgie.os nisse,td adcnyuc rer,ie ncn otnsd ucstecolarfps a,c iatnladen ackeia ngdeu ctance,
arger outpoegde itnCh hearp 1t1e.r
Thqeu antaintudin eiusts sei dnt hbioso akrp er imairnai clcyo rwdiattnhhcI een ternSaytsitoenma l
(S.aIn.td)h s ey mbaorlaessfa ra sp ossciobnlseiw sittIehEn PCtu blic2a7Tt.hi irosen p reseinst ation
rapisdulpye rstehCde.i Gn.pgSr .a cstyisctaHelom w.e vaesmr a,n rye adweirblselm orfaem ilwiiatrh
thliast styesrti hetam bs e einn clausad nea dl terinnta htfoeil vleo wwianyIg.nt hmea itne txhtee q ua
tioanrisen S .uIn.i etxsc ienpr ta crea swehse arnee quaitasip opnl iocnalibynsl oem oet h(esrt ated)
systIetfmh C.e. G.vSe.r soifaon nu mbeerqeuda dtiiffofrenor mst hSe. vIe.r stihoCen. ,G .vSe.r siiso n
givienanfo otnoUtnel.me susl tioprsl uebs- mualrtseip pelceisifi ncdailcltayhst eye mdb,ro elfetsrot he
basuincio tfts ha ep propsryisatIteafnem u .m beerqeuda dtoienosonh t a vafoe o tnotei mtve earnssi on
thtahtSe . aIn.Cd . G.vSe.r sairoiend se nptriocvatilhd aeepd p ropurniiaatrtusees eIdnt. h ger aphs,
scahlaevbsee egni vienbn o tshy stoefum nsiw thse nreec essary. E.C.S.
Acknowledgements
Ing athetrhmiean tge forrit ahblio so akn pdr epairfotir pn ugb litchaaetu itohhnoa brse efonr tuniant e
havtihnaegs sisatncadno c-eo peorfaan tuimobonefp r e oapnloder ganizaanhdtew i iosnthsoee, xs p ress
higsr atittoau lodlfte h eAml.t hoiuitgns ho p to sstiomb elnet tihoenam lb lyn amheew oullidtk oe
makteh foel lowing specific acknowledgements.
MrH.. J ackpsroonv uisdeedfudal to anfe rrmiatneu facatnuDdrr Fe..W, .H arriMsrJo.E.n .K, n owles
anMdr C.. V .N ewcocmobn trihbeultpsefuudlg gecsotniocnetsrh nfieir nasgnt td h icrhda ptTehres .
acquiasnimdta irosnh aolftl hidena gtfo arC hap3tw earas m ajtoarsa kn vda luaasbslies wtaasn ce
provbiydh eicdso lleMargA.u. Ge .Ds a bnMeryF.,.G .P ronMgreA.r. W, a tearnisdn p artiMcru.l ar
N.C .0 .J ackIsnCo hna.p 4tt ehdrei scuosfcs oirfaoecn t obresn efrfiotmec do rrespwointMdhreE .n. ce
Olsaenntd h mee asureomnfee rnrtist ew errmeoa ddbsey M rP.. J ohnsMornB... A stle bayssisted
chectkhipneog ct o roep timirzeastuoilnott nhsc e o mpuatnehdre p rovihdeeldpc fuolm meonnta s
numboefsr u bjCehcatps7t.c e orn tmauicnthsh haatis to sr igiintn haseu theoarrt'lrsya iinnti rnagn s
formedre sainghdne a cknowtlhetedu gietisint o hsniu sb jtehchatetr ecefriovmte hdle a DtreJ. M. o le
anfrdo ma nu npublriesphboeyrMd tr C .. H ooijkaGmrpa.ta ecfukln owleiddsgu etemoM e rnsVt..B .
Ingrwahmot ypmeodso tft hfien amla nusctroMi rpsLt..S, t rudawniMdci ksP s.A .W ebwbh ot yped
mucohft hper eparmaattoetrroyMi raslA.,.I P.r onwgheopr r epaalrtlehd dei agarnaidml sl ustrations,
antdot hocsoel lewahgoau sessiw sitttehhdc e h ecokfit nhpger ooFfisn.ao lnal m yo,rp ee rsnoontael,
thaeu thwoirs thoer se cogtnhhieez laepn e dn ormpoautsi oefhn icwsei wfeh oe xpetchttaehtdwe o rk
wouolcdc umpoyn tbhufostu ntdh iactto nsuymeeadr s.
Specaicakln owleiddsgu etemot e hDneit r ecotfMo urlslL atrfoddr p ermitsops uibolinint s hbhi oso k
three soufwl otrsd ko noent hebierh aRleffe.r rpianrgt itcouC lhaarp3ltt yeha reu twhiosrth oee xsp ress
hiasp prectioaa lttlhim eoa nn ufacwthuokr ienrmdsal dyae v aidlaatobanlt eh efeirrrm iattee rainadl s,
whos ubseqcuheenctaklneyadd p protvhdeeed t apirleesde notfta hteciioornn t ribTuhtmei aonnus.
factuwrheorc so -opeirnta htaiersade s fo llowAsl:a dCdoimnp onLetndGt.rs,e enMfoirddd,l esex,
EnglaAnldlB.er na dCloemyp aMniyl,w auWkiesec,o Un.sSi.nCA,e. r aMmaigcn e(tnicFc.as,i r,fi eld
NewJ ersUe.yS,.C Ao.m pagdneiFsee rrEielctter uoensPi,qa rFirsa,n CcOeP.R IEMv,r eEuuxr,e ,
FranFcaei.r -PRriotdeuC cotrspW .a,l l,kN iewl loYrkU,. S.FAe.r roxCcourbpeo rSaatuigoenr,t ies,
NewY orUk.,S .FAr.i Kerdu.p Wpi dia-FEasbsreGinek,r, m aInnyd.i Gaennae CroarlpK .e,a sbey,
NewJ ersUe.yS,.L Ai.g nTeesl egraeptTh eilqeupehso PnairqFiursea,sn ,Mc aeg.n eItnicBc.us,l ter,
PennsylUv.aSn.MiAua.l, l LatrddL. o,n doEnn,g laNnadt.i oMnoalldC iotmep aInnycN .e,w ark,
NewJ ersUe.yS,.N Ae.o sLitddW .e,l wGyanr dCeintH ye,r tfordEsnhgilraNene,do .sP iedm etzrieder
G.m.BH.aHl.vi,enW r e stfaGleernm,aN niyp.pE olne cCtorL.it cdM .i,n atToo-kkyuJo,a, p Nainp,p on
FerrIintdeu sCtoLr.ti daS.lh, i nju,Tk ouk-yJkoau,p Na.nV ..P hilGilpos� ilampenfabrieken, Eindhoven,
HollaTnhdeP. l esCsoemyp aLntyd T.o,w cesNtoerrt,h amptEonngslhaSinardle.fo,E r lde cltrica
InstruLmtedHn.et,ys w oLoadn,c aEsnhgilrSaein,ed m.Ae .nGsM. u,n iGcehr,m aSnoynC.yo rporation,
ShinagaTwoak-yJkoau,p, Sa nt.a ckCpaorlbCeoo nm paSntMy.a, r yP'esn,n syUl.vSa.nSAit.aa ,n dard
TelepahnoCdna ebsLl tedsH. a,r lEosws,Ee nxg,l Satneda.Mt aigtneeP soirRazh,,e bienKi o lGne,r many.
D.MS.t ewMaarndu factCuormipnagCn hya,t tanToeongnaeU,s. sSe.eTA,o. h oMkeut Ianld ustries
LtdC.h,u o-TlockuyJ,oa ,p Vaanl.Gv .om .bH.aHm.b,u Gregr,m any.
