Zeziphi izizathu zobushushu kwi-MOSFET ye-inverter?

I-inverter'sIi-MOSFETssebenza kwisimo sokutshintsha kwaye i-current flowing through the tubes iphezulu kakhulu. Ukuba ityhubhu ayikhethwanga ngokufanelekileyo, i-voltage ye-voltage yokuqhuba ayinkulu ngokwaneleyo okanye ukuchithwa kobushushu besiphaluka akulunganga, kunokubangela ukuba i-MOSFET ishushu.

1, inverter MOSFET ukufudumeza kunzulu, kufuneka ingqalelo ukhetho MOSFET

I-MOSFET kwi-inverter kwisimo sokutshintsha, ngokubanzi ifuna i-drain yayo yangoku inkulu ngokusemandleni, ukuxhathisa okuncinci kangangoko kunokwenzeka, okunokunciphisa ukuhla kwamandla ombane wetyhubhu, ngaloo ndlela kuncitshiswe ityhubhu ukususela ekusetyenzisweni, ukunciphisa ubushushu.

Qwalasela incwadi ye-MOSFET, siya kufumanisa ukuba okukhona liphezulu ixabiso le-voltage yokumelana ne-MOSFET, kokukhona ukuxhathisa okukhulu, kunye nezo zinexabiso eliphantsi le-drain yangoku kunye nexabiso eliphantsi lokumelana ne-voltage yetyhubhu, ukuxhathisa kwayo kungaphantsi kwamashumi iimiliyoni.

Ukucinga ukuba umthamo wangoku we-5A, sikhetha i-inverter esetyenziswa ngokuqhelekileyo i-MOSFET RU75N08R kunye nexabiso lokumelana ne-voltage ye-500V 840 ingaba, i-drain current yabo i-5A okanye ngaphezulu, kodwa ukuchasana kweetyhubhu ezimbini kwahlukile, qhuba i-current efanayo. , umahluko wabo wobushushu mkhulu kakhulu. I-75N08R kwi-resistance yi-0.008Ω kuphela, ngelixa i-on-resistance ye-840 yi-0.85Ω, xa umthwalo wangoku ohamba nge-tube yi-5A, i-75N08R i-voltage ye-tube drop yi-0.04V kuphela, ngeli xesha, ukusetyenziswa kwetyhubhu ye-MOSFET kuphela i-0.2W, ngelixa i-840 ityhubhu yehla yombane inokufikelela kwi-4.25W, ukusetyenziswa ityhubhu kuphezulu njenge-21.25W. Ukusuka kule nto kunokubonwa, encinci ukuchasana kwe-inverter ye-MOSFET yeyona nto ingcono, i-on-resistance ye-tube inkulu, ukusetyenziswa kwetyhubhu phantsi kwangoku okuphezulu Ukumelana nokumelana kwe-MOSFET ye-inverter kuncinci. kangangoko kunokwenzeka.

I-2, isiphaluka sokuqhuba i-voltage ye-voltage amplitude ayinkulu ngokwaneleyo

I-MOSFET sisixhobo sokulawula umbane, ukuba ufuna ukunciphisa ukusetyenziswa kwetyhubhu, ukunciphisa ubushushu,I-MOSFETi-gate drive voltage amplitude kufuneka ibe nkulu ngokwaneleyo ukuze uqhube umphetho we-pulse ukuba ube ngumnqantsa kwaye uthe tye, unganciphisa ukuhla kombane wetyhubhu, unciphise ukusetyenziswa kwetyhubhu.

3, Ukutshatyalaliswa kobushushu be-MOSFET ayisosizathu silungileyo

InverterI-MOSFETukufudumeza kunzulu. Njengoko i-inverter MOSFET ukusetyenziswa kwamandla kukhulu, umsebenzi ngokubanzi ufuna indawo enkulu eyaneleyo yangaphandle ye-heatsink, kunye ne-heatsink yangaphandle kunye ne-MOSFET ngokwayo phakathi kwe-heatsink kufuneka inxibelelane ngokusondeleyo kunye (ngokubanzi kufuneka iqatywe ngegrisi ye-silicone eqhubayo. ), ukuba i-heatsink yangaphandle incinci, okanye uqhagamshelwano ne-MOSFET ye-heatsink ngokwayo alusondele ngokwaneleyo, kunokukhokelela ekufudumeni kwetyhubhu.

Inverter MOSFET ukufudumeza serious kukho izizathu ezine zesishwankathelo.

Ukufudumeza okuncinci kwe-MOSFET yinto eqhelekileyo, kodwa ukufudumeza okunzulu, nokukhokelela kwityhubhu kutshiswe, kukho ezi zizathu zilandelayo:

1, ingxaki yoyilo lwesekethe

Vumela i-MOSFET isebenze kwimeko yokusebenza ehambelanayo, endaweni yemo yesekethe yokutshintsha. Ikwangomnye woonobangela bokufudumala kweMOSFET. Ukuba i-N-MOS yenza utshintsho, i-voltage ye-G kufuneka ibe yi-V embalwa ngaphezu kokunikezelwa kwamandla ngokupheleleyo, ngelixa i-P-MOS ichasene. Ayivulekanga ngokupheleleyo kwaye ukuhla kwamandla ombane kukhulu kakhulu okukhokelela kusetyenziso lwamandla, i-impedance ye-DC elinganayo inkulu, ukuhla kwe-voltage kuyanda, ngoko ke i-U * ndiyanyuka, ilahleko ithetha ubushushu. Le yeyona mpazamo iphephe kakhulu kuyilo lwesekethe.

2, i-frequency ephezulu kakhulu

Esona sizathu siphambili kukuba ngamanye amaxesha ukusukela ngokugqithisileyo umthamo, okukhokelela ekunyukeni rhoqo, ilahleko yeMOSFET enkulu, ngoko ke ubushushu buyanda.

3, akwanelanga uyilo thermal

Ukuba i-current iphezulu kakhulu, ixabiso eliqhelekileyo langoku le-MOSFET, lidla ngokufuna ukuchithwa kakuhle kobushushu ukuze kuphunyezwe. Ke i-ID ingaphantsi kobona buninzi bangoku, inokufudumeza kakubi, idinga isinki yobushushu eyaneleyo.

4, ukhetho lwe-MOSFET alulunganga

Isigwebo esingalunganga samandla, ukuchasana kwangaphakathi kwe-MOSFET akuqwalaselwa ngokupheleleyo, okukhokelela ekunyuseni kokutshintsha kokutshintsha.