ucd 25 watts to 1200 watts using 2 mosfets

[stewin]

Originally Posted by andrewlebon

Hi NN20
greetings not much difference in irs1500 pcb i reccomend irs3000 pcb layout
because i have made it and @2 ohms load very little heat
warm regards
andrew lebon

what voltage and fets were you using? did you push it hard at 2 ohms?

[stewin]

Originally Posted by andrewlebon

Hi Stewin
greetings 90N20 FETS are being used at 93 volts dc+/-
for irf260n 100 ohms stewin please try to get proper core for pro RESULT and the smps is tough dc rails shorted pri fuse blows its our first step in smps higher power still to come
warm regards
andrew lebon

thanks michelle i,ll have to use ee cores from smps power supply with piece of cd to make 1mm gap, until i get my hands on the red or black toroid core.

[nn20]

Originally Posted by andrewlebon

Hi NN20
greetings not much difference in irs1500 pcb i reccomend irs3000 pcb layout
because i have made it and @2 ohms load very little heat
warm regards
andrew lebon

ok thanks . I will make irs 3000. but can use 1 pair of IRFP250 for it? load impedance is 4 ohms. and voltage is +-60 volts.

thanks
regard

[stewin]

hi andrew pls post the pcb files of the irs3000d the one using bd 139 and 140 as buffers gate drivers

thanking you in advance stewin

[pergo]

Originally Posted by stewin

thanks pergo. so the smps produces 1.2kwts or less?

>>>>and irfp460 fets are they superior compared to IRG4PC50U in smps , because irfp460 can run with 100khz?

don't know if produce that power.
Yamaha says 750x2 @4ohm, so you've to generate something like 2kW.
The IGBT doesn't make the power, but the transformer design.
2 IGBT are ok for that power, they can handle 55A each! At 220Vac side, 55A is a huge current.

IRG4PC50U, according to datasheet, are "optimized" up to 40kHz in hard switching but you can use them at 100kHz if you design well the driver circuit, transformer, deadtime, etc..
IRFP460 are less current, bit faster, but obsolete.

IRG4PC50U are good for a <100kHz smps, like an half-bridge design.

[Pafi]

Originally Posted by pergo

don't know if produce that power.
Yamaha says 750x2 @4ohm, so you've to generate something like 2kW.
The IGBT doesn't make the power, but the transformer design.
2 IGBT are ok for that power, they can handle 55A each! At 220Vac side, 55A is a huge current.

IRG4PC50U, according to datasheet, are "optimized" up to 40kHz in hard switching but you can use them at 100kHz if you design well the driver circuit, transformer, deadtime, etc..
IRFP460 are less current, bit faster, but obsolete.

IRG4PC50U are good for a <100kHz smps, like an half-bridge design.

The datasheet is very user friendly, they specify safe load current in real life circumstances:
http://www.irf.com/product-info/data.../irg4pc50u.pdf
See Fig. 1 - Typical Load Current vs. Frequency ! The curve drawn with _.._.._

16A @ 40 kHz and 10 A @ 100 kHz. Transformer, dead time and other things are not specified. They supposed to be well designed. Nobody specify their product for using in badly designed environment, so no overdrive can be recommended just because "you design it well".

For limited time higher current can be allowed though, esecially if (while) heat sink is cold.

For efficiency calculations you must consider switching loss.
Switching loss is 0.5-2 mJ (details in datasheet). For examle at 100 kHz 1 mJ is 100 W.

[stewin]

Thanks Pergo, I will try to incorporate those IGBT with the below design to get at least 2.5 KW. I will use 85KHZ.

Do you have a link to show/guide how to coil/design IGBT transformer.

Thanks Pafi, so if I use 30KHZ I will have the freedom to go up to 40 Amps at +/- 85V?



Am a bit illiterate with calculations, please forgive my many questions. And may the Almighty GOD JEHOVAH bless you all for your replies.

[pergo]

for a 2.5kW you need a huge transformer, something like PM74 (http://www.tauscher-transformatoren..../pdf/hf_64.pdf) or two ETD59 if you switch below 100kHz.

[stewin]

thanks pergo now i understand if i decide to go with low frequency, i will have to hustle for a complex transformer etd42-54 can't help.

thanks again

[irvynejay]

Originally Posted by pergo

for a 2.5kW you need a huge transformer, something like PM74 (http://www.tauscher-transformatoren..../pdf/hf_64.pdf) or two ETD59 if you switch below 100kHz.

what about this core ? Marked N87