Txhawm rau nrov LED luminaires, tsis tsuas yog xav tau txo tus nqi, tab sis kuj yuav tsum daws teeb meem kev teeb meem. Yuav daws cov teeb meem ntawm lub zog ntawm hluav taws xob thiab kev ntseeg tau li cas, Doug Bailey, tus lwm thawj coj ntawm kev ua lag luam rau PowerIntegrations, qhia txog cov kev paub ntawm cov txiaj ntsig zoo thiab txhim khu kev ntseeg ntawm tus tsav tsheb tsim LED.
Ua ntej tshaj plaws, tsis txhob siv cov khoom siv fais fab bipolar
Doug Bailey taw qhia tias vim tias cov cuab yeej hluav taws xob bipolar pheej yig dua li MOSFET, feem ntau li 2 xees, qee cov neeg tsim qauv siv cov khoom siv hluav taws xob bipolar los txo nqi LED tsav nqi, uas tuaj yeem cuam tshuam loj rau kev ntseeg tau vim hais tias nrog LED. Raws li qhov kub ntawm cov tsav tsheb nce, qhov ua haujlwm tau zoo ntawm cov cuab yeej bipolar yuav poob sai. Qhov no yuav ua rau lub cuab yeej ua haujlwm tsis zoo thaum lub ntsuas kub nce, yog li cuam tshuam qhov kev cia siab ntawm cov taws teeb ntawm LED. Qhov tseeb yog xaiv cov MOSFET ntaus ntawv thiab lub neej ua haujlwm ntawm MOSFET ntaus ntawv. Nws ntev dua li cov khoom siv bipolar.
Thib ob, sim tsis txhob siv lub ntsuas hluav taws xob
Koj puas xav siv lub tshuab hluav taws xob hauv qhov hluav taws xob hauv LED tsav tsheb Circuit Court? Muaj cov kws txhawb nqa thiab tawm tsam. Cov neeg txhawb nqa ntseeg tau hais tias yog tias qhov ntsuas kub ntawm pawg tswj hwm yuav tuaj yeem tswj tau, lub hom phiaj txuas ntxiv lub neej ntawm cov electrolytic capacitor tuaj yeem ua tiav. Piv txwv li, lub ntsuas hluav taws xob muaj qhov ntsuas kub ntawm qhov ntsuas hluav taws xob nrog lub neej ntawm 105 degrees thiab lub neej ntev txog 8000 teev yog xaiv, raws li cov qauv qhia tseeb rau lub neej ntawm electrolytic capacitor. "Txhua zaus qhov ntsuas kub tau qis los ntawm 10 degrees, lub neej muaj ob npaug", tom qab ntawd nws muaj lub neej ua haujlwm ntawm 16,000 teev nyob rau hauv ib puag ncig 95 degree, lub neej ua haujlwm ntawm 32,000 teev nyob rau hauv ib puag ncig 85 degree, thiab lub neej ua haujlwm ntawm 64,000 teev nyob rau hauv ib puag ncig 75 degree, yog tias qhov kub ua haujlwm qis dua, yog li lub neej ua haujlwm ntev dua! Txij ntawm qhov pom no, ntev li ntev tau xaiv cov khoom hluav taws xob zoo hluav taws xob tsis muaj qhov cuam tshuam rau lub neej ntawm tsav hluav taws xob!
Lwm cov neeg tshaj tawm kev ntseeg siab hais tias qhov qis qis flicker tshwm sim los ntawm lub siab tam sim no tshwm sim los ntawm lub tshuab hluav taws xob tsis zoo yuav ua rau lub cev tsis xis nyob rau qee tus neeg lub qhov muag. Qhov loj dav ntawm qhov luv-tsawg ripple tseem yuav ua rau qee cov cuab yeej siv xov tooj digital tsis zoo. Lub teeb ci, tsaus ntais ntawm flickering teeb. Yog li no, zoo lub teeb pom kev zoo lub teeb tseem xav tau lub ntsuas hluav taws xob. Txawm li cas los xij, cov neeg sib tw ntseeg tias electrolytic capacitors yuav pib lub hnub nyoog. Tsis tas li ntawd, qhov kub ntawm LED teeb yog qhov nyuaj rau kev tswj hwm, yog li lub neej ntawm electrolytic capacitors yuav zam tsis dhau, yog li cuam tshuam lub neej ntawm LED teeb.
Hauv qhov no, Doug Bailey ntseeg hais tias qhov kev nkag ntawm ib feem ntawm LED tsav tsheb Circuit Court tuaj yeem txiav txim siab yam tsis muaj electrolytic capacitors. Qhov tseeb, PI LinkSwitch-PH tuaj yeem txuag lub tshuab hluav taws xob. PI ib leeg-theem PFC / tsis tu ncua tsim qauv tam sim no tso cai rau cov neeg tsim qauv tuaj yeem txuag lub peev xwm loj. Capacitor, hauv cov tso zis Circuit Court, high-voltage ceramic capacitors tuaj yeem siv hloov ntawm electrolytic capacitors los txhim kho kev ntseeg tau. "Qee tus neeg tsim qauv ob-theem Circuit Court, siv lub 400V electrolytic capacitor ntawm qhov tsim tawm, uas yuav cuam tshuam loj heev rau hauv Circuit Court. Kev ntseeg tau, nws pom zoo kom siv cov ceramic capacitors rau ib theem kev sib kis," nws hais. "Rau cov ntawv thov kev lag luam uas tsis muaj kev txhawj xeeb nrog qhov chaw dim, qhov kub thiab nyob ib puag ncig, thiab qhov twg muaj kev ntseeg siab tau, Kuv xav kom tsis txhob siv electrolytic capacitors rau kev tsim."
Thib peb, MOSFET's lub zog voltage yuav tsum tsis txhob qis dua 700V
600V MOSFET yog qhov pheej yig dua. Coob tus neeg xav tias qhov hluav taws xob voltage ntawm LED teeb hluav taws xob feem ntau yog 220V, yog li qhov ntsuas voltage ntawm 600V yog txaus, tab sis feem ntau qhov hluav taws xob Circuit Court yuav ncav cuag 340V. Hauv qhov xwm txheej loj, 600V MOSFET yog yooj yim rhuav. Yog li ntawd, lub neej ntawm LED teeb raug cuam tshuam. Qhov tseeb, kev xaiv ntawm 600V MOSFET tuaj yeem txuag qee tus nqi tab sis tus nqi ntawm tag nrho pawg tsav tsheb tau raug them. Yog li no, "Tsis txhob siv 600V tiv thaiv voltage MOSFET, thiab nws yog qhov zoo dua los siv MOSFET nrog lub zog voltage siab dua 700V. Nws hais txog.
Qeb plaub, sim sim siv rau ib ntu kev sib luag ntu Circuit Court Circuit Court
Doug tau hais tias qee qhov kev sib kis ntawm LED siv ob-theem tsim ua ntu tsim, uas yog "PFC (Lub Hwj Huam Ua Tau Kho) + Cov Hluav Taws Xob DC / DC Hloov Hluav Taws Xob", uas yuav txo cov kev ua haujlwm ntawm Circuit Court. Piv txwv li, yog hais tias qhov ua tau zoo ntawm PFC yog 95% thiab qhov ua tau zoo ntawm DC / DC seem yog 88%, qhov ua haujlwm ntawm tag nrho Circuit Court yuav raug txo kom 83.6%! "PI's LinkSwitch-PH ntaus ntawv ua ke nrog PFC / CC maub los, 725V MOSFET thiab MOSFET tsav tsheb mus rau hauv ib pob, nce kev ua haujlwm ntawm tus tsav tsheb mus rau 87%!" Doug ntsiab lus tawm hais tias, "Cov khoom siv no yooj yim piv rau pawg thawj coj saib." Tsim los mus tshem tawm mus txog 25 feem siv nyob rau hauv cov tsoos ib txwm flyback designs! Raug tshem tawm cov khoom suav nrog cov hluav taws xob ntau hluav taws xob cov roj hluav taws xob thiab cov chaw tsim hluav taws xob. "Doug hais tias LED ob-theem tsim hluav taws xob yog tsim nyog rau kev siv nrog qhov thib ob tsis hloov tam sim no Lub voj voos tso cai rau PFC tsav lub LED qhov hloov pauv tam sim rau tus tsav qub. Cov qauv tsim no yog qhov qub dhau thiab tsis raug nqi, yog li feem ntau nws yog qhov zoo tshaj plaws los siv ib theem qauv tsim.
Thib tsib, sim siv MOSFET cov khoom siv
Yog tias cov luminaires LED tsis tsim kom muaj zog heev, Doug pom zoo kom siv cov tsav tsheb LED nrog lub MOSFETs sib koom ua ke vim tias qhov txiaj ntsig ntawm qhov no yog MOSFETs sib koom ua ke muaj tsawg dua-ua haujlwm thiab tsim kom muaj cua sov tsawg dua kev txiav txim siab, ntxiv rau kev sib xyaw MOSFETs. Cov maub los thiab FET feem ntau ua ke, thiab feem ntau muaj cov thermal kaw ua haujlwm. Thaum MOSFET dhau los ua cua sov, lub Circuit Court yuav muab tua kom tsis txhob tiv thaiv LED teeb. Qhov no yog qhov tseem ceeb heev rau LED teeb, vim hais tias LED teeb feem ntau me me thiab tsis yooj yim rau huab cua. Cov. Nws tau hais tias "Qee lub sijhawm LED tuaj yeem ua rau tib neeg hlawv vim tias muaj qhov kub dhau, tab sis peb cov kev daws teeb meem tsis tau zoo li no,"