400VDC rail
driver is IRF2110
the transformer is 750315374,(400V:24V)
inductor: 2303-V-RC (15uf, 18A)
power of converter is 400W

 

Another issue I am having is that the fuse in the first converter(interleaved boost converter) is always burning/breaking whenever I power it, before applying PWM I have used irfp840, and irfp460, but it keeps on breaking the fuse, I don't know if its the MOSFET, the AC input is 230VAC.

 

Not sure that transformer is good enough to meet 400W Its spec'd as 12v x 10A x 2 = 240W for 380-400v in (see datasheet attached). Whats your expected DC output volts/current?

Why do you have inductor in series with transformer primary? That would be right for a LLC converter (with a C in series too) but not for a PSFB converter.

How did you calculate the output inductor value?

 

Another issue I am having is that the fuse in the first converter(interleaved boost converter) is always burning/breaking whenever I power it, before applying PWM I have used irfp840, and irfp460, but it keeps on breaking the fuse, I don't know if its the MOSFET, the AC input is 230VAC.

Nothing to do with MOSFET. Your boost converter has a big inrush current problem... What fuse are you using...

 

Transformer: 750315374

yes: 250V

U13 - U16 (FCPF600N60Z )

drivers: IRF2110.

THANKS YOU SIR.

 

mosfet driver is irf2110
250 vdc rail
yes I am referring to U13 - U16
20mH inductor
transformer is 750315374

 

How do i determine the number of mosfet for my smps

 

the burning fuse hs been taken care of.

I need to know howmanu ifp460 i will use for 1kw smps i parallel

 

Can you please answer questions in post #23

 

Forgive me if I haven't followed all the messages in this thread, but to measure 400VDC I wonder if you could use an op amp pair, one as an oscillator to generate a square wave to switch the other between zero and (a constant fraction) of the 400V. Then isolate with a 1:1 digital audio transformer - for example the MuRata DA100 series and let the processor do the ADC. May not be terribly accurate but could perhaps be calibrated to provide a satisfactory result...

 

Forgive me if I haven't followed all the messages in this thread, but to measure 400VDC I wonder if you could use an op amp pair, one as an oscillator to generate a square wave to switch the other between zero and (a constant fraction) of the 400V. Then isolate with a 1:1 digital audio transformer - for example the MuRata DA100 series and let the processor do the ADC. May not be terribly accurate but could perhaps be calibrated to provide a satisfactory result...

Isolated op-amps use a modulated RF carrier where the modulation frequency is relative to the input volts. They have an input to output gain of 1.

My preference is to use a dual photocoupler like a Vishay IL300. This has a LED and two matched photodiodes. The LED current is driven by an opamp and the output of 1 photodiode is used as the feedback loop for the driving opamp. The other photodiode drives another opamp whose output now mirrors the input voltage to the first opamp. Obviously the opamps need to be good quality, preferably zero-drift instrumentation amps,and run from isolated power supplies.

 

Hello,

Page 12 of the datasheet shows the use of the IL300 @Irving mentioned, with the formulas.

Or you could have a look at some isolation amplifiers like the ISO122 or ISO124.

Bertus

 

Or you could have a look at some isolation amplifiers like the ISO122 or ISO124.

Bertus

I've used the ISO122 before, but its not a great op-amp withan input offset of 50mVtoo expensive at £20 in 1000up for a consumer switch-mode power supply.

A better device is TI's AMC1211A with a 1.5mV offset and only £4/1000up, though it is limited to a 2v dynamic range compared to the ISO122's +/-10v range.