effect of the switching losses

[olemp]

mosfet losses

hi! what is the rate of the switching losses in the all mosfet losses...
i am asking this for the mosfets which working hard switching condition....
for example 60khz forward converter mosfet (dc bus voltage 310V) , hard switching and we are driving the gate in optimum speed....(to understand how much ZVS or ZCS helps us)

 

[nicleo]

mosfet switching waveforms

I hope the following article and excel-calculator are useful to you:

Synchronous buck MOSFET loss calculations with Excel model
http://www.fairchildsemi.com/an/AN/AN-6005.pdf
http://www.fairchildsemi.com/collateral/AN-6005.zip


Besides, you might be interested in the following articles:

MOSFET Switching: the Real Waveforms. Part I - Turn-ON, Hard Switching
**broken link removed**

MOSFET Switching: the Real Waveforms. Part II - Turn-ON, Soft Switching
**broken link removed**

MOSFET Switching: the Real Waveforms. Part III - Turn-OFF
**broken link removed**

 

[olemp]

switching losses in hard switching

thank you nicleo...i'll read the articles that you sent..
but still i need a basic ansver: how many?? (percent of the switching losses in the all mosfet losses)

 

[nicleo]

dc-dc fet loss calculator

https://journals.tubitak.gov.tr/elektrik/issues/elk-02-10-3/elk-10-3-5-0203-2.pdf[/url] ]Converter 1: A standard forward converter having a reset winding with Schottky output rectifiers. Main switch is switched lossy (Non-ZVS).

Converter 2: An active clamp forward converter with Schottky output rectifiers. Main switch is switched lossy (Non-ZVS).

Converter 3: An active clamp forward converter with Schottky output rectifiers and a magnetic amplifier that enables soft switching of the main switch (ZVS).

Converter 4: A standard forward converter having a reset winding with control driven synchronous rectifiers. Main switch is switched lossy (Non-ZVS).

Converter 5: An active clamp forward converter with synchronous rectiers and a magnetic amplifier. All switches are soft switched (ZVS).