Zifukwa zazikulu ziwiriof MOSFET kulephera:
Kulephera kwamagetsi: ndiye kuti, voteji ya BVdss pakati pa kukhetsa ndi gwero imaposa mphamvu yamagetsi yamagetsiMOSFET ndikufikira mphamvu inayake, kupangitsa MOSFET kulephera.
Kulephera kwa Voltage ya Gate: Chipata chimakhala ndi kukwera kwamphamvu kwamagetsi, zomwe zimapangitsa kuti chipata cha oxygen chilephereke.
Kuwonongeka kwamagetsi (kulephera kwamagetsi)
Kodi kuwonongeka kwa chigumula ndi chiyani kwenikweni? Mwachidule,ndi MOSFET ndi njira yolephereka yomwe imapangidwa ndi kuchulukana pakati pa ma voltages a mabasi, ma voltages owonetsera ma transfoma, ma voltages otayikira, ndi zina zambiri ndi MOSFET. Mwachidule, ndikulephera kofala komwe kumachitika pamene voteji yomwe ili pamtsinje wa MOSFET idutsa mtengo wake wamagetsi ndikufika pamlingo wina wa mphamvu.
Njira zopewera kuwonongeka kwa avalanche:
-Chepetsani mlingo moyenera. Mumakampani awa, nthawi zambiri amachepetsedwa ndi 80-95%. Sankhani potengera zomwe kampaniyo ikufuna komanso zofunika kwambiri.
- Magetsi owonetsera ndi omveka.
-RCD, TVS mayamwidwe dera kapangidwe ndi wololera.
-Mawaya apamwamba apano akuyenera kukhala akulu momwe angathere kuti achepetse inductance ya parasitic.
-Sankhani chopinga choyenera pachipata Rg.
-Onjezani RC damping kapena Zener diode mayamwidwe pamagetsi apamwamba ngati pakufunika.
Kulephera kwa Magetsi a Gate
Pali zifukwa zazikulu zitatu zomwe zimachititsa kuti magetsi azikwera kwambiri: magetsi osasunthika panthawi yopanga, kuyendetsa ndi kusonkhana; mkulu voteji resonance kwaiye magawo parasitic zipangizo ndi mabwalo pa ntchito mphamvu dongosolo; ndi kutumiza ma voltage okwera kudzera mu Ggd kupita ku grid panthawi yamphamvu yamagetsi (cholakwika chomwe chimakhala chofala kwambiri pakuyesa kugunda kwamphezi).
Njira zopewera kuwonongeka kwa ma gate voltage:
Kutetezedwa kwa overvoltage pakati pa chipata ndi gwero: Pamene kutsekeka pakati pa chipata ndi gwero kuli kokwera kwambiri, kusintha kwadzidzidzi kwa voteji pakati pa chipata ndi gwero kumalumikizidwa ndi chipata kudzera pa capacitance pakati pa ma elekitirodi, zomwe zimapangitsa kuti voteji ya UGS ikhale yokwera kwambiri, zomwe zimatsogolera pakuwongolera kwambiri pachipata. Kuwonongeka kosatha kwa okosijeni. Ngati UGS ili pamagetsi abwino osakhalitsa, chipangizocho chingayambitsenso zolakwika. Pazifukwa izi, kutsekeka kwa dera loyendetsa zipata kuyenera kuchepetsedwa moyenera ndipo chowongolera chotsitsa kapena 20V chokhazikika chamagetsi chiyenera kulumikizidwa pakati pa chipata ndi gwero. Chisamaliro chapadera chiyenera kuchitidwa pofuna kupewa kutsegula chitseko.
Kutetezedwa kwa overvoltage pakati pa machubu otulutsa: Ngati pali inductor m'derali, kusintha kwadzidzidzi kwa kutayikira kwapano (di / dt) pomwe chipangizocho chazimitsidwa chidzapangitsa kuti voteji iwonongeke bwino pamwamba pa voteji, zomwe zimapangitsa kuwonongeka kwa unit. Chitetezo chiyenera kukhala ndi Zener clamp, RC clamp, kapena RC kupondereza dera.
Nthawi yotumiza: Jul-17-2024
