Hello all
I try to make simple but powerfull SMPS for audio amp. or similar equipment.
I have one IGBT brick SKM75GB123,and I like to use it in SMPS.
This IGBT isn't for high frequencies,and this means that oscillator must have f. about 20~30kHz.
I make a simple oscillator like from CFL bulb or similar device but with voltage feedback.
Oscilator make fine square waves with +/-16V amplitude.This is fine for IGBT.
In IGBT gate I add 56R and diode,diode is for fast turn off and 56R is used to make small delay on turn on.This will prevent cross conduction.56R may wary if use another type of IGBT.Fet's can be used too.For small FET's and IGBT's like IRFP460 and IRG4PC40W use about 100R instead of 56.
It's tested about half hour on 1kW continiously,IGBT is warm,oscillator is cool
In few days I'll try to make pcb.Tomorrow I'll post some pictures in operating.
BDT core is salvaged from CFL bulb.This is small toroid
E33 can be used original,without rewinding.I'll explain tomorrow how to do it.
Now,here's schematic:
Input rectifier and filter is ommited for simplicity.Secondary rectifier have storage inductor after diodes.
I try to make simple but powerfull SMPS for audio amp. or similar equipment.
I have one IGBT brick SKM75GB123,and I like to use it in SMPS.
This IGBT isn't for high frequencies,and this means that oscillator must have f. about 20~30kHz.
I make a simple oscillator like from CFL bulb or similar device but with voltage feedback.
Oscilator make fine square waves with +/-16V amplitude.This is fine for IGBT.
In IGBT gate I add 56R and diode,diode is for fast turn off and 56R is used to make small delay on turn on.This will prevent cross conduction.56R may wary if use another type of IGBT.Fet's can be used too.For small FET's and IGBT's like IRFP460 and IRG4PC40W use about 100R instead of 56.
It's tested about half hour on 1kW continiously,IGBT is warm,oscillator is cool
In few days I'll try to make pcb.Tomorrow I'll post some pictures in operating.
BDT core is salvaged from CFL bulb.This is small toroid
E33 can be used original,without rewinding.I'll explain tomorrow how to do it.
Now,here's schematic:
Input rectifier and filter is ommited for simplicity.Secondary rectifier have storage inductor after diodes.
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