replacement mosfet for solar charge converter

[Chamjisky]

Hi
I have solar mppt converter. it has lmitiation on input solar panels. Its maximum solar input voltage is 150volts.
but its mosfets burn when voltage is ~140v dc.

Currently it has IRFP 4568 and IPP075N15N3.

last time when i repaired i used IRFB4115. Now i want to use 3 solar panels with it so i want to increase its input voltage rating to 155 volts maximum.

I want to use IRFP 4668 as replacement for 4568.

Also i want to use HY1920P as replacement for IPP075N15N3. However its RDS on and Qg are higher. These 5 mosfets are driven by TLP250.

Would it work ? The mosfet has big heatsink and thermally controlled fan . There is resistance of 4.7k between gate/source of each mosfet.

The board will accet to220 and to247 as it has drills for both mosfets. so if you have any recomendation. i will try to find in local market or aliexpress online as these are the only platforms that are economical and ship to my country.

 

[aliarifat794]

IRFP4668 and HY1920P should work as replacements.

 

[Chamjisky]

@aliarafat794
here is the circuit . The top has two irf4568 in parrallel and the lower one is five mosfets 075n15n3 in parallel all have seperate gate and gateToSource resisitance while all five are driven be tl250.

Is it realy a buck converter ? does mosfet work in these arrangment ? the diode is 40100PT shocotkey diode. the cap at input from S+/B+ (solar and battery positive terminal) are 4 200v 1000 uf. and he capp after inductor are three 63v 2200 uf.

and does chanigng the mosfets would help me allow input of <160volts ? do i need to also replace MBR40100PT ? i have few MBR60200PT. i am confused as it rated for 150 volts max but mbr are 100v ?

 

[Chamjisky]

IRFP4668 and HY1920P should work as replacements.

Thanks bro for your reply. i have installed hy1920p .. do i need to change the gate resisotors as well as the gate capacitance is different for these mosfets.
i have access to oscillscope .. i watched few videos about miller plateau .
if i want to see this plateau on oscilliscope where i need to put the oscilliscope probes to observer the miller plateu ?

 

[Gaber Mohamed Boraey]

Not slower?

IRFP4668 and HY1920P should work as replacements.