Capacitor Characterization hauv Switching Power Supply EMC Tsim
Ntau tus neeg tsim hluav taws xob tau paub txog lub luag haujlwm ntawm cov lim capacitors hauv cov khoom siv hluav taws xob, tab sis nyob rau hauv lubswitching fais fab movtso zis nrog lub lim capacitor, thiab cov zaus muaj circuits tsis zoo ib yam li cov lim capacitor xaiv nyob rau hauv industrial zaus Circuit Court siv raws li ib tug lim ntawm zoo tib yam electrolytic capacitors, zaus ntawm nws pulsating voltage tsuas yog 100 hertz, them thiab tawm lub sij hawm yog milliseconds. kev txiav txim ntawm qhov loj me, txhawm rau kom tau txais qhov me me coefficient ntawm pulsation, xav tau lub peev xwm txog li pua pua txhiab tus microfarads! Yuav kom tau txais ib qho me me pulsation coefficient, qhov yuav tsum tau muaj peev xwm yog siab li ntau pua txhiab microfarads, thiab yog li cov capacitors tsis tshua muaj hluav taws xob yog tsim los ntawm cov khoom siv hluav taws xob zoo tib yam aluminium electrolytic capacitors, thiab lub hom phiaj yog txhawm rau txhim kho lub peev xwm.
Nyob rau hauv lub switching regulator raws li ib tug tso zis lim nrog electrolytic capacitors, zaus ntawm lub sawtooth yoj voltage mus txog kaum ntawm kilohertz, los yog txawm kaum ntawm megahertz, nws yuav tsum tau thiab tsawg zaus daim ntawv thov yog txawv, lub peev xwm tsis yog lub ntsiab qhia los ntsuas. nws qhov zoo lossis qhov tsis zoo yog nws qhov impedance thiab zaus yam ntxwv, qhov yuav tsum tau muaj ntawm kev hloov regulator kom muaj qhov impedance tsawg nyob rau hauv cov zaus band, tib lub sij hawm, rau cov khoom siv fais fab, vim cov khoom siv semiconductor pib tib lub sijhawm, rau Cov khoom siv hluav taws xob sab hauv, vim tias cov khoom siv hluav taws xob semiconductor pib ua haujlwm siab txog ntau pua kilohertz tsim los ntawm lub suab nrov nrov, tab sis kuj muaj cov nyhuv lim dej zoo, feem ntau qis zaus nrog cov electrolytic capacitors zoo tib yam hauv 10 kilohertz los yog li ntawd, lub impedance. yuav pib qhia inductive, tsis tuaj yeem ua tau raws li qhov xav tau ntawm kev hloov hluav taws xob siv hluav taws xob.
Switching tswj fais fab mov tshwj xeeb high zaus txhuas electrolytic capacitors, nws muaj plaub-terminal tub, zoo txhuas daim ntawm ob kawg ntawm qhov zoo electrode raws li ib tug capacitor, qhov tsis zoo txhuas daim ntawm ob kawg ntawm qhov tsis zoo electrode raws li ib tug tsis zoo electrode. . Kev tswj fais fab mov tam sim no los ntawm plaub lub davhlau ya nyob twg capacitor ntawm qhov kawg ntawm qhov nkag mus, los ntawm lub capacitor sab hauv, thiab tom qab ntawd los ntawm lwm qhov kawg mus rau qhov load; los ntawm lub load rov qab mus rau tam sim no los ntawm lub capacitor ntawm qhov tsis zoo kawg ntawm cov inflow, thiab tom qab ntawd los ntawm lwm qhov tsis zoo kawg mus rau qhov tsis zoo kawg ntawm lub hwj chim mov.
Vim hais tias plaub-terminal capacitor muaj cov yam ntxwv siab zaus, nws yog los txo cov pulsating tivthaiv ntawm cov zis hluav taws xob nrog rau kev tawm tsam ntawm kev hloov cov suab nrov nrov muab ib qho txiaj ntsig zoo heev.
High-frequency aluminium electrolytic capacitors kuj muaj daim ntawv ntawm ntau cov tub ntxhais, nws yuav muab faib ua ib tug xov tooj ntawm luv luv seem ntawm txhuas ntawv ci, nrog rau ntau tshaj cov hlau lead daim ntawv txuas mus rau lub parallel thiaj li yuav txo tau cov resistive tivthaiv nyob rau hauv lub capacitance impedance, Nyob rau tib lub sijhawm, kev siv cov khoom siv tsis tshua muaj siab thiab cov ntsia hlau ua cov hlau lead terminals, txhawm rau txhim kho lub capacitor kom tiv taus lub peev xwm ntawm qhov siab tam sim no.
Stacked capacitors tseem hu ua non-inductive capacitors, dav electrolytic capacitors yog dov mus rau hauv ib tug cylindrical core, qhov sib npaug series inductance loj dua; stacked capacitors thiab cov qauv ntawm phau ntawv zoo ib yam li cov kev taw qhia ntawm cov flux generated los ntawm cov ndlwg ntawm tam sim no raug muab tso tseg, yog li txo qhov inductance ntawm tus nqi ntawm ib tug zoo heev high-frequency yam ntxwv ntawm lub capacitor yog feem ntau ua rau ib tug square los pab txhim kho, tab sis kuj tuaj yeem raug txo kom tsim nyog rau tus account rau qhov loj ntawm lub tshuab.
Tsis tas li ntawd, muaj kev sib xyaw ua ke ntawm plaub-terminal thiab laminated plaub-terminal laminated high-frequency electrolytic capacitors, uas muab cov txiaj ntsig zoo ntawm ob qho tib si, cov yam ntxwv siab zaus zoo dua.
