Yiziphi izimbangela zokushisisa kwe-inverter MOSFET?

I-MOSFET ye-inverter isebenza esimweni sokushintsha futhi yamanje egeleza nge-MOSFET iphezulu kakhulu. Uma i-MOSFET ingakhethiwe kahle, i-voltage amplitude yokushayela ayinkulu ngokwanele noma ukuchithwa kokushisa kwesekethe akukuhle, kungabangela i-MOSFET ukushisa.

 

1, inverter MOSFET Ukushisa sina, kufanele sinakeI-MOSFETukukhetha

I-MOSFET ku-inverter esimweni sokushintsha, ngokuvamile idinga i-drain yayo enkulu ngangokunokwenzeka, ukumelana nokumelana kube kuncane ngangokunokwenzeka, ukuze ukwazi ukunciphisa ukwehla kwamandla kagesi we-MOSFET, ngaleyo ndlela unciphise i-MOSFET kusukela ekusetshenzisweni, ukunciphisa ukushisa.

Hlola imanuwali ye-MOSFET, sizothola ukuthi lapho ukuphakama kwevelu ye-sightstanding ye-MOSFET, iba nkulu ukumelana kwayo, kanye nalawo ane-drain current ephezulu, inani eliphansi lokumelana ne-voltage ye-MOSFET, ukumelana kwayo ngokuvamile kungaphansi kwamashumi amamiliyoni.

Uma sicabanga ukuthi umthamo wamanje we-5A, sikhetha i-inverter evame ukusetshenziswa i-MOSFETRU75N08R futhi imelane nevelu ye-voltage engu-500V 840 ingaba, i-drain current yabo iku-5A noma ngaphezulu, kodwa ukumelana nokumelana kwama-MOSFET amabili ahlukile, shayela okwamanje okufanayo. , umehluko wabo wokushisa mkhulu kakhulu. I-75N08R on-resistance ingu-0.008Ω kuphela, kuyilapho ukumelana kwe-840 kwe-on-resistance kwe-75N08R kungu-0.008Ω kuphela, kuyilapho ukumelana no-840 kungu-0.85Ω. Lapho umthwalo wamanje ogeleza ku-MOSFET ungu-5A, ukwehla kwamandla kagesi we-75N08R's MOSFET kungu-0.04V kuphela, kanti ukusetshenziswa kwe-MOSFET kwe-MOSFET kungu-0.2W kuphela, kuyilapho ukwehla kwamandla ka-840 MOSFET kungase kufike ku-4.25W, kanye nokusetshenziswa ye-MOSFET iphezulu njenge-21.25W. Kulokhu, kungabonakala ukuthi ukumelana nokumelana kwe-MOSFET kuhluke ekuphikisaneni kwe-75N08R, futhi isizukulwane sabo sokushisa sihluke kakhulu. Okuncane ukumelana nokumelana kwe-MOSFET, kungcono, ukumelana ne-MOSFET, ishubhu le-MOSFET ngaphansi kokusetshenziswa okuphezulu kwamanje likhulu impela.

 

2, isifunda sokushayela se-voltage amplitude asisikhulu ngokwanele

I-MOSFET iyithuluzi lokulawula i-voltage, uma ufuna ukunciphisa ukusetshenziswa kweshubhu le-MOSFET, unciphise ukushisa, i-MOSFET gate drive voltage amplitude kufanele ibe nkulu ngokwanele, ishayela umphetho we-pulse ibe umqansa, inganciphisaI-MOSFETi-tube voltage drop, yehlisa ukusetshenziswa kweshubhu ye-MOSFET.

 

3, Ukushisa kwe-MOSFET akusona isizathu esihle

Ukushisa kwe-Inverter MOSFET kubucayi. Njengoba ukusetshenziswa kweshubhu le-MOSFET ku-inverter kukhulu, umsebenzi ngokuvamile udinga indawo enkulu eyanele yangaphandle ye-sink yokushisa, futhi usinki wokushisa wangaphandle kanye ne-MOSFET ngokwayo phakathi kwe-heater sink kufanele isondelene (ngokuvamile iyadingeka ukuthi imbozwe nge-thermal conductive. i-silicone grease), uma usinki wokushisa wangaphandle umncane, noma i-MOSFET ngokwayo ingasondeli ngokwanele ekuthinteni usinki wokushisa, kungaholela ekushisiseni kwe-MOSFET.

Inverter MOSFET Ukushisa sina kunezizathu ezine isifinyezo.

Ukushisa okuncane kwe-MOSFET kuyinto evamile, kodwa ukushisa kubi, futhi ngisho nokuholela ku-MOSFET ishisiwe, kunezizathu ezine ezilandelayo:

 

1, inkinga yokuklama kwesifunda

Vumela i-MOSFET isebenze esimweni sokusebenza esilandelanayo, esikhundleni sokushintshwa kwesiyingi. Kuphinde kube ngesinye sezimbangela zokushisisa kweMOSFET. Uma i-N-MOS yenza ukushintsha, i-voltage yeleveli ye-G kufanele ibe ngama-V ambalwa ngaphezu kwamandla ukuze ivuleke ngokugcwele, kuyilapho i-P-MOS iphambene. Ayivuleki ngokuphelele futhi ukwehla kwe-voltage kukhulu kakhulu okuholela ekusetshenzisweni kwamandla, i-impedance ye-DC efanayo inkulu, ukwehla kwe-voltage kuyanda, ngakho-ke u-U * nami ngiyakhuphuka, ukulahlekelwa kusho ukushisa. Leli iphutha eligwenywe kakhulu ekwakhiweni kwesekethe.

 

2, imvamisa ephezulu kakhulu

Isizathu esiyinhloko ukuthi ngezinye izikhathi ukuphishekela ngokweqile kwevolumu, okuholela ekwandeni kwemvamisa,I-MOSFETukulahlekelwa okukhulu, ngakho ukushisa nakho kuyanda.

 

3, ukuklama okwanele okushisayo

Uma i-current iphezulu kakhulu, inani lamanje le-MOSFET, ngokuvamile lidinga ukulahlwa kokushisa okuhle ukuze kufinyelelwe. Ngakho-ke i-ID ingaphansi komkhawulo wamanje, ingase futhi ishise kabi, idinge usinki wokushisa owanele.

 

4, ukukhethwa kwe-MOSFET akulungile

Ukwahlulela okungalungile kwamandla, ukumelana kwangaphakathi kwe-MOSFET akucatshangelwa ngokugcwele, okuholela ekwandeni kokuphazamiseka kokushintsha.