Lub sijhawm rov qab los ntawm lub diode cuam tshuam li cas rau kev siv hluav taws xob?

Ib, Lub cev tseem ceeb ntawm lub sijhawm rov qab los: qhov kev ua si ntawm tus nqi cia thiab tso tawm
Thaum lub sij hawm hloov cov txheej txheem ntawm diode los ntawm pem hauv ntej conduction mus rau thim rov qab, cov neeg nqa khoom tsawg khaws cia hauv PN hlws ris (xws li cov hluav taws xob hauv cheeb tsam P thiab qhov hauv cheeb tsam N) tsis tuaj yeem ploj tam sim ntawd, tab sis yuav tsum tau ua raws li cov txheej txheem tso tawm. Cov txheej txheem no tuaj yeem muab faib ua ob theem:

Cia theem (ts): Tom qab rov qab qhov hluav taws xob tau thov, cov cab kuj concentration gradient tsav tus nqi kom diffuse nyob rau hauv qhov kev taw qhia rov qab, tsim lub ncov rov qab tam sim no (IRM).
Qhovntsej thiaj tsis mob theem (tf): Tus nqi yog maj mam recombined los yog muab rho tawm, thiab qhov rov qab tam sim no decays exponentially mus rau qhov to tam sim no theem (Irr).
Lub sijhawm ntawm tag nrho cov txheej txheem yog lub sijhawm rov qab los (trr=ts+tf). Ua ib qho kev rov qab sai sai diode (FRD) ua piv txwv, nws TRR feem ntau yog nyob rau hauv thaj tsam ntawm 50-500ns, thaum Schottky diode (SBD) tuaj yeem txo TRR mus rau qib nanosecond lossis txawm ze rau xoom vim tsis muaj cov neeg nqa khoom tsawg.

2, Poob mechanism: yuav ua li cas thim rov qab devours zog efficiency
Cov txheej txheem rov qab rov qab ua rau lub zog poob los ntawm peb txoj hauv kev, cuam tshuam ncaj qha rau kev ua haujlwm ntawm lub cev:

1. Hloov poob
Hauv siab - zaus hloov daim ntawv thov, cov khoom siv hluav taws xob xws li diodes thiab MOSFETs ua ke. Thaum lub diode tsis tau muab tua tag, MOSFET pib ua, tsim ib qho "cross conduction" tshwm sim, ua rau tam sim no luv luv -circuit tam sim no.

2. Kev poob qis
Thaum lub sij hawm rov qab cov txheej txheem rov qab, lub diode raug rau qhov rov qab voltage thaum tseem tab tom muaj kev conduction voltage poob.

3. Kev cuam tshuam hluav taws xob (EMI) poob
Kev hloov pauv sai ntawm qhov rov qab rov qab tam sim no (siab di / dt) yuav tsim cov hluav taws xob hluav taws xob ntawm cov kab mob parasitic inductance ntawm Circuit Court, tsim cov conduction thiab hluav taws xob cuam tshuam. Piv txwv li, hauv PFC circuits, TRR ntev ntev ntawm lub zog diode tuaj yeem ua rau 30% nce hauv qhov ntim ntawm EMI lim, ntxiv txo qhov kev ua haujlwm tag nrho ntawm lub cev.

3, Kub dependence: efficiency vau nyhuv ntawm kub kub
Lub sijhawm rov qab thim rov qab muaj qhov kub thiab txias rhiab heev, thiab nws qhov kev hloov pauv tau nthuav tawm cov nyhuv "ob-edged ntaj":
Rov qab mus rau theem rov qab: qhov kub thiab txias yuav ua rau lub neej ntev dua thiab nce TRR. Piv txwv li, 600V ultrafast rov qab diode muaj trr ntawm 35ns ntawm 25℃C, tab sis txuas mus rau 120ns ntawm 125℃C, ua rau 240% nce hauv kev poob poob.
Qhov no tsis yog - tus yam ntxwv linear yog qhov txaus ntshai tshwj xeeb hauv cov khoom siv fais fab. Ib tus neeg siv khoom tau tshaj tawm tias qhov ua tau zoo ntawm lawv cov 48V / 50A server fais fab mov poob los ntawm 5% hauv qhov kub thiab txias. Tom qab kev tshawb fawb, nws tau pom tias qhov thib ob rectifier diode tau ntsib qhov nce ntawm qhov kev sib tw hla kev poob vim TRR kub nce. Los ntawm kev hloov nws nrog silicon carbide Schottky diode (SiC SBD), tsis tsuas yog lub trr ruaj khov nyob rau hauv 15ns, tab sis lub junction kub kam rau siab kuj nce mus rau 175℃C, thiab lub system efficiency yog rov qab mus rau ntau tshaj 94%.

4, Kev Siv Hluav Taws Xob: Kev Ua Haujlwm Zoo Tshaj Plaws los ntawm kev xaiv los tsim
1. Kev xaiv ntaus ntawv: ib qho kev hloov pauv ntawm cov ntaub ntawv thiab cov qauv
Silicon carbide (SiC) diode: Nrog nws cov yam ntxwv dav bandgap, SiC diode ua tiav xoom rov qab rov qab (trr ≈ 0ns), txhim kho kev ua tau zoo los ntawm 3-5% hauv high-frequency topologies xws li PFC thiab LLC. Cov ntaub ntawv kawm ntawm photovoltaic inverter qhia tau hais tias tom qab siv SiC diodes, qhov kev ua haujlwm tau zoo tau nce los ntawm 97.2% mus rau 98.1%, thiab kev txuag hluav taws xob txhua xyoo tau sib npaug los txo CO ₂ emissions los ntawm 12 tons.
Mos rov qab diode: Los ntawm optimizing doping concentration thiab junction qhov tob, txoj kab nqes ntawm rov qab rov qab tam sim no txo ​​(df / dt) yog txo los ntawm 50%, txo voltage spikes. Piv txwv li, thaum tus tsav lub cev muaj zog siv lub diode rov qab los, qhov ntim ntawm EMI lim tau txo los ntawm 40%, thiab cov kev ua haujlwm tau zoo dua los ntawm 1.2%.
2. Circuit Court tsim: kev sib koom ua ke optimization ntawm topology thiab tswj
Synchronous rectification technology: Hloov freewheeling diodes nrog MOSFETs kom tshem tawm qhov rov qab poob poob. Tom qab siv synchronous rectification, qhov ua tau zoo ntawm qee lub laptop adapter tau nce los ntawm 85% mus rau 92%, thiab qhov kub siab nce los ntawm 25 ° C.
Kev tswj lub sijhawm tuag: Los ntawm kev kho lub sijhawm tuag ntawm MOSFET tsav teeb liab, kev hla kev raug zam. Tom qab tau txais kev tswj hwm qhov chaw tuag, qee qhov kev lag luam hluav taws xob txo qis kev hloov pauv los ntawm 60% thiab nce kev ua tau zoo mus rau 95%.
3. Thermal tswj: los ntawm passive tshav kub dissipation mus rau active tsim
Kev ntim khoom kom zoo: Siv cov khoom ntim uas tsis muaj cua sov xws li DFN thiab TO-247 los txo qhov cuam tshuam ntawm qhov kub thiab txias ntawm TRR. Ib lub tsheb charger siv DFN8 × 8 ntim kom ruaj khov TRR ntawm SiC diodes ntawm 150℃C.
Thaum tshav kub kub dissipation txoj kev tsim: Thaum ntau lub raj txuas nrog rau qhov sib npaug, qhov sib koom tam sim no los yog cov qauv thermal coupling ntxiv kom tsis txhob muaj cua sov hauv zos. Ib qho kev sib txuas lus fais fab kev lag luam tau ua kom zoo dua nws cov cua kub dissipation tsim los tswj qhov kub ntawm qhov sib txawv ntawm cov diodes nyob rau hauv 5℃C, ua rau 20% nce efficiency stability.