Metallized zaj duab xis capacitors yog siv dav hauv cov khoom siv hluav taws xob hluav taws xob, hluav taws xob hluav taws xob, hluav taws xob hluav taws xob, hluav taws xob hluav taws xob, thiab kev lag luam automation vim lawv tus kheej zoo heev - muaj peev xwm kho tau, poob qis, thiab kev ntseeg siab. Txawm li cas los xij, nyob rau hauv kev ua haujlwm hnyav xws li kub, av noo, overvoltage, thiab mechanical stress, lawv qhov kev ua tau zoo maj mam deteriorates, nws thiaj li ua rau tsis ua hauj lwm.

 

Cov txheej txheem tsis ua haujlwm ntawm metallized zaj duab xis capacitors feem ntau tuaj yeem muab faib ua plaub pawg:electrochemical corrosion, dielectric breakdown, capacitance degradation, thiab kev ua haujlwm tsis ua haujlwm. Hauv kev siv cov tswv yim, cov kev ua tsis tiav no feem ntau yog tsav los ntawm ntau yam -physics coupling cuam tshuam nrog hluav taws xob teb, kub, av noo, thiab mechanical stress.

 

Kuv, Hom Kev Ua Tsis Taus Feem Ntau thiab Cov Kev Pom Zoo

Kev ua tsis tiav ntawm metallized zaj duab xis capacitors feem ntau cuam tshuam ob qho tib si hluav taws xob tsis zoo thiab lub cev kev puas tsuaj.

 

Hom kev ua tsis tiav	Tej yam tshwm sim	Kev cuam tshuam rau cov khoom siv
Capacitance Degradation	Maj mam txo qis capacitance thaum tseem nyob hauv qhov ntsuas qhov ntsuas kom txog thaum tsis ua tiav sai	Txo kev them nyiaj ua haujlwm, lub sijhawm yuam kev, oscillation instability
Rwb thaiv tsev tsis ua hauj lwm	Ua kom cov dej xau tam sim no thiab txo cov rwb thaiv tsev tsis kam	Ntau dua thermal poob, muaj kev pheej hmoo ntawm thermal runaway
Dielectric kev puas tsuaj	Dielectric zaj duab xis melting thiab puncture, tsim txoj kev conductive	Luv - Circuit Court burnout thiab ua tiav cov cuab yeej tsis ua haujlwm
Kev ua tsis tiav	Internal tawg, solder sib koom detachment, pob cracking	Qhib - Circuit Court tsis ua hauj lwm thiab cuam tshuam ntawm cov dej ntws tam sim no

 

II, Core Failure Mechanisms ntawm Metallized Film Capacitors

1. Electrochemical Corrosion thiab Moisture Ingress

Electrochemical corrosion yog ib qho ntawm cov txheej txheem kev laus hauv AC filtering thiab kev siv hluav taws xob them nyiaj.

 

Thaum lub sealing kev ua tau zoo ntawm lub metallized zaj duab xis capacitor tsis txaus, noo noo tuaj yeem nkag mus rau hauv cov qauv sab hauv, txo cov huab cua tawg voltage thiab nrawm ionization ntawm cov khaubncaws sab nraud povtseg. Lub ozone generated thaum lub sij hawm no ionization txheej txheem oxidizes metallized electrodes (Zn/Al), ua tsis yog -conductive oxides xws li ZnO thiab Al₂O₃. Raws li oxidation zuj zus, qhov zoo electrode cheeb tsam maj mam txo qis, uas ua rau cov capacitance degradation tsis tu ncua.

 

Nyob rau hauv ib puag ncig uas txheeb ze av noo tshaj 85%, electrochemical migration kuj yuav tshwm sim nyob rau hauv lub metallized txheej, tsim conductive dendrites uas nws thiaj li ua rau inter-electrode luv circuits.

 

Nyob rau hauv sulfur-muaj los yog acidic gas ib puag ncig, tus nqi corrosion yuav nce 3-5 zaug. Corrosion ntawm lub davhlau ya nyob twg tin plating ho nce kev tiv thaiv, ua rau overheating thiab kev twb kev txuas tsis ua hauj lwm.

 

Cov teebmeem tseem ceeb

• Capacitance degradation
• Txo rwb thaiv tsev tsis kam
• Terminal overheating
• Luv -circuit risk

 

2. Kev ntxhov siab ntawm hluav taws xob thiab rov ua dua tus kheej - Kev poob zoo

Ib qho ntawm cov yam ntxwv tseem ceeb ntawm metallized film capacitors yog lawv tus kheej - kho muaj peev xwm. Thaum muaj qhov sib txawv ntawm cov dielectric hauv ib cheeb tsam, cov txheej txheej metallized nyob ib ncig ntawm qhov txhaum sai vaporizes, cais thaj chaw puas thiab tso cai rau lub capacitor txuas ntxiv ua haujlwm ib txwm.

Txawm li cas los xij, rov ua nws tus kheej- cov xwm txheej kho kom zoo maj mam siv thaj chaw zoo metallized electrode, ua rau txo qis peev xwm thiab tsis muaj zog tiv thaiv kev muaj peev xwm.

 

Cov kev tshawb fawb sim qhia tias:

• Ntau zaus nws tus kheej-kho qhov paug tawm sai sai ua rau lub peev xwm degradation
• Dielectric withstand voltage txo ua ke nrog txo capacitance
• Txo qis dua capacitance ua rau kev ua haujlwm tsis zoo ntawm rwb thaiv tsev

 

3.Overvoltage teebmeem

Overvoltage yog ib qho kev cuam tshuam ncaj qha rau kev puas tsuaj loj dielectric.

 

Vim hais tias capacitor fais fab tuag nce kwv yees li square ntawm kev khiav hauj lwm voltage, ntev - lub sij hawm overvoltage ua hauj lwm accelerates dielectric aging thiab cov cua sov sab hauv. Lub caij no, lub sijhawm hloov pauv hluav taws xob tshwm sim los ntawm kev hloov pauv lossis kev cuam tshuam hauv kab sib chaws tuaj yeem ncav cuag ob peb zaug ntawm qhov ntsuas hluav taws xob, ncaj qha rau lub dielectric txheej.

 

Raws li IEEE tshawb fawb:

Thaum lub zog hluav taws xob nce mus txog 10⁶ V / cm, qhov kev tso tawm sab hauv yuav nce exponentially nrog kub

Rau txhua txhua 10℃nce nyob rau hauv qhov kub thiab txias, qhov tshwm sim ntawm ib nrab tso tawm kwv yees li ob npaug

 

Cov teebmeem tseem ceeb

• Accelerated tus kheej - kho noj
• Nce qhov kub thiab txias nce
• Dielectric puncture
• Thermal khiav
• Sudden kev puas tsuaj

 

4.Multiphysics Coupling Accelerated Aging Mechanisms

Nyob rau hauv cov xwm txheej hnyav,metallized zaj duab xis capacitorKev ua tsis tiav yog feem ntau tshwm sim los ntawm kev sib txuas ntawm cov hluav taws xob hluav taws xob, qhov kub thiab txias, av noo, thiab kev ntxhov siab.

 

4.1. Electric Field - Kub Coupling

Kev kub siab txo qhov dielectric lub zog thiab dielectric tas li ntawm polypropylene (PP) zaj duab xis, ua rau thaj chaw hluav taws xob txhim kho. Qhov hluav taws xob ntau ntxiv ua rau lub zog sab hauv dissipation thiab kub, tsim kom muaj kev tawm tswv yim zoo.

Qhov tshwm sim no ua rau hauv cheeb tsam "kub qhov chaw," qhov twg qhov kub tuaj yeem nce mus rau ntau pua degrees Celsius, thaum kawg melting dielectric zaj duab xis thiab ua rau muaj kev puas tsuaj loj.

 

Qhov tshwm sim

• Local thermal concentration
• Ib nrab tso tawm intensification
• Zaj duab xis yaj
• Thermal breakdown tsis ua hauj lwm

 

4.2. Kub-Mechanical Stress Coupling

Lub thermal expansion coefficients ntawm aluminium metallization thiab polypropylene dielectric zaj duab xis sib txawv heev. Thaum lub sij hawm kub caij tsheb kauj vab, muaj qhov cuam tshuam loj ntawm kev sib tshuam shear yog tsim.

 

Qhov kev ntxhov siab tuaj yeem ncav cuag li 50 MPa nyob rau hauv kev rov ua dua thermal cycling. Thaum cov khoom siv qaug zog dhau lawm, microcracks tsim hauv txheej metallized.

 

Nyob rau tib lub sijhawm, qhov ntsuas kub siab nrawm nrawm:

• Hlau diffusion
• Cov tshuaj tiv thaiv oxidation
• Aluminium oxide txheej kev loj hlob
• Qhov kev loj hlob ntawm oxidation yog kwv yees peb npaug rau txhua txhua 10℃nce hauv qhov kub thiab txias.

 

Qhov tshwm sim

• Metallization cracking
• Nce ESR
• Txo hluav taws xob conductivity
• Accelerated kev laus

 

4.3. Mechanical Stress Coupling

Mechanical stress thaum lub sij hawm sib dhos PCB, kev thauj mus los, kev co, thiab kev teeb tsa kuj tuaj yeem cuam tshuam qhov kev cia siab ntawm capacitor.

PCB dabtsi yog khoov kev nyuaj siab tshaj 2000 microstrain, nrog rau ntev - lub sij hawm vibration los yog cuam tshuam loading, tej zaum yuav ua rau:

• Sab hauv zaj duab xis tawg
• Solder Joint qaug zog
• Terminal detachment
• Pob deformation

 

Cov neeg kho tshuab microcracks no kuj dhau los ua txoj hauv kev rau cov dej noo ingress thiab corrosion propagation, ntxiv accelerating electrochemical aging.

 

Qhov tshwm sim

• Qhib - Circuit Court tsis ua haujlwm
• Intermittent hluav taws xob tiv tauj
• Moisture nkag
• Txo kev ua haujlwm lub neej

 

5.Kev tsim khoom thiab txheej txheem tsis raug

Manufacturing defects yog lwm qhov tseem ceeb ntawm kev ua tsis tiav thaum ntxov hauv metallized zaj duab xis capacitors.

 

Cov txheej txheem nquag- cuam tshuam txog qhov tsis xws li:

• Impurities nyob rau hauv raw cov ntaub ntawv
• Uneven metallized txheej thickness
• Pinhole defects nyob rau hauv dielectric zaj duab xis
• Tsis tiav lub tshuab nqus tsev kom qhuav thiab dehumidification
• Tsis zoo encapsulation

 

Cov teeb meem no tsim cov ntsiab lus hauv cheeb tsam hluav taws xob hauv cheeb tsam, ua rau ib nrab tawm thiab dielectric tawg ntau dua thaum ua haujlwm.

Residual internal ya raws qhia thaum lub sij hawm ntim ntxiv accelerates corrosion thiab rwb thaiv tsev degradation los ntawm thawj theem ntawm kev pab cuam lub neej.

 

Qhov tshwm sim

Thaum ntxov - lub neej ua tsis tiav

Localized dielectric kev puas tsuaj

Txo kev cia siab

Shortened kev pab lub neej

 

III, Conclusion

Kev ntseeg ntawmmetallized zaj duab xis capacitorsyog muaj zog cuam tshuam los ntawm hluav taws xob kev nyuaj siab, ib puag ncig tej yam kev mob, thermal tswj, mechanical loading, thiab manufacturing zoo. Ntawm tag nrho cov txheej txheem tsis ua hauj lwm, electrochemical corrosion, rov ua tus kheej- kho noj, dielectric breakdown, thiab multiphysics coupling cuam tshuam yog cov tseem ceeb cuam tshuam rau lub sij hawm ntev - kev ua tau zoo thiab kev pab lub neej.

 

Txhawm rau txhim kho capacitor kev ntseeg tau thiab lub neej ua haujlwm, cov kev ntsuas hauv qab no yog qhov tseem ceeb:

• Txhim kho sealing thiab tiv thaiv noo noo
• Kev tswj xyuas thermal thiab qhov cua kom zoo
• Overvoltage thiab harmonic suppression
• Txo cov neeg kho tshuab kev nyuaj siab thaum lub sij hawm installation
• High - zoo dielectric film manufacturing thiab encapsulation txheej txheem

 

Nrog rau kev tsim kho kom zoo, xaiv cov khoom siv, thiab kev tiv thaiv ib puag ncig, metallized zaj duab xis capacitors tuaj yeem ua tiav kev ruaj ntseg, kev nyab xeeb, thiab kev ua haujlwm ruaj khov hauv cov tshuab hluav taws xob niaj hnub no.