Kev siv cov hlaws sib nqus hauv EMC tsim ntawm kev hloov hluav taws xob
1 Ferrite electromagnetic cuam tshuam kev tiv thaiv
Ferrite yog cov khoom siv ferrimagnetic nrog lub cubic lattice qauv. Nws cov txheej txheem tsim khoom thiab cov khoom siv tshuab zoo ib yam li ceramics, thiab nws cov xim yog grey-dub. Ib hom hlau nplaum feem ntau siv hauv cov ntxaij lim dej electromagnetic cuam tshuam yog cov khoom siv ferrite. Ntau lub tuam txhab muab cov ntaub ntawv ferrite tshwj xeeb siv rau kev cuam tshuam electromagnetic cuam tshuam. Cov khoom no yog tus cwj pwm los ntawm kev poob siab heev ntawm cov frequencies siab. Rau ferrites siv los suppress electromagnetic cuam tshuam, qhov tseem ceeb tshaj plaws kev ua tau zoo tsis yog magnetic permeability μ thiab saturation magnetic flux ceev Bs. Sib nqus permeability μ tuaj yeem qhia tau tias yog tus lej nyuaj, qhov tseeb yog qhov inductance, thiab qhov xav txog qhov nruab nrab yog qhov poob, uas nce nrog qhov nce ntawm zaus. Yog li ntawd, nws sib npaug Circuit Court yog ib tug series Circuit Court uas muaj ib tug inductor L thiab ib tug resistor R. Ob leeg L thiab R yog functions ntawm zaus. Thaum ib tug hlau hla los ntawm no ferrite core, qhov inductive impedance tsim nyob rau hauv daim ntawv raws li qhov zaus nce, tab sis nws cov mechanism yog txawv kiag li ntawm ntau zaus.
Hauv qhov tsawg zaus band, impedance yog tsim los ntawm inductive reactance ntawm inductor. Ntawm qhov tsawg zaus, R yog qhov me me thiab qhov sib nqus permeability ntawm cov tub ntxhais sib nqus yog siab, yog li qhov inductance loj. L ua lub luag haujlwm tseem ceeb. Kev cuam tshuam ntawm electromagnetic cuam tshuam yog cuam tshuam thiab cuam tshuam; thiab lub sijhawm no, cov hlau nplaum Cov tub ntxhais poob yog me me, thiab tag nrho cov cuab yeej yog ib qho inductor uas tsis tshua muaj poob thiab siab Q yam ntxwv. Qhov inductor no yooj yim ua rau resonance. Yog li ntawd, nyob rau hauv qhov tsawg zaus band, cuam tshuam tej zaum yuav txhim kho tom qab siv ferrite hlaws dai.
Nyob rau hauv lub high zaus band, lub impedance yog tsim los ntawm cov khoom tiv thaiv. Raws li qhov zaus nce, qhov sib nqus permeability ntawm cov tub ntxhais hlau nplaum yuav txo qis, ua rau cov inductance ntawm inductor txo thiab cov inductive reactance tivthaiv txo. Txawm li cas los xij, nyob rau lub sijhawm no, qhov poob ntawm cov tub ntxhais sib nqus nce thiab cov khoom tiv thaiv tsis kam nce. , ua rau tag nrho impedance nce. Thaum high-frequency signals dhau los ntawm ferrite, electromagnetic cuam tshuam yog absorbed thiab hloov mus rau hauv tshav kub zog thiab dissipated.
Ferrite suppression Cheebtsam yog dav siv nyob rau hauv cov ntawv luam Circuit Court boards, fais fab kab thiab cov ntaub ntawv kab. Yog hais tias ib tug ferrite suppression tivthaiv yog ntxiv rau lub inlet kawg ntawm lub hwj chim kab ntawm lub luam Circuit Court board, high-frequency cuam tshuam yuav raug lim tawm. Ferrite magnetic rings los yog magnetic hlaws dai tshwj xeeb yog siv los tiv thaiv kev cuam tshuam ntau zaus thiab cuam tshuam ntawm cov kab teeb liab thiab cov kab hluav taws xob. Nws kuj muaj peev xwm nqus tau electrostatic tawm mem tes cuam tshuam.
2 Lub hauv paus ntsiab lus thiab cov yam ntxwv ntawm Magnetic Beads Thaum tam sim no ntws los ntawm cov xaim hauv qhov nruab nrab, ib qho kev sib nqus sib nqus yuav raug tsim tawm hauv cov hlaws sib nqus. Ferrites siv rau EMI tswj yuav tsum tau tsim kom dissipate feem ntau ntawm cov hlau nplaum flux li cua sov hauv cov khoom. Qhov tshwm sim no tuaj yeem simulated los ntawm kev sib xyaw ua ke ntawm inductor thiab resistor. raws li pom hauv daim duab 2
Cov naj npawb ntawm cov khoom ntawm ob lub ntsiab lus yog proportional rau qhov ntev ntawm cov hlaws sib nqus, thiab qhov ntev ntawm cov hlaws sib nqus muaj qhov cuam tshuam loj heev rau kev tawm tsam. Qhov ntev ntawm qhov ntev ntawm cov hlaws sib nqus, qhov zoo dua qhov kev tawm tsam. Txij li thaum lub teeb liab lub zog yog sib nqus ua ke rau cov hlaws sib nqus, qhov reactance thiab tsis kam ntawm inductor nce raws li qhov zaus nce. Qhov ua tau zoo ntawm kev sib nqus sib nqus nyob ntawm qhov sib nqus permeability ntawm cov khoom siv hlaws txheeb ze rau huab cua. Feem ntau qhov poob ntawm cov khoom siv ferrite uas ua rau cov hlaws sib nqus tuaj yeem qhia tau tias muaj ntau yam los ntawm nws qhov sib nqus permeability txheeb ze rau huab cua.
Cov ntaub ntawv sib nqus feem ntau siv qhov piv txwv no los qhia qhov poob lub kaum sab xis. Cov khoom siv rau EMI kev tawm tsam yuav tsum muaj lub kaum sab xis loj, uas txhais tau hais tias feem ntau ntawm kev cuam tshuam yuav ploj mus yam tsis muaj kev cuam tshuam. Ntau yam ntawm cov ntaub ntawv ferrite muaj tam sim no muab cov neeg tsim qauv nrog ntau yam kev xaiv rau kev siv cov hlaws sib nqus hauv ntau qhov xwm txheej.
