How to decide what smps I need for project hybrid amp.


@ Kees54, Try this Resonant smps design it may help you out. This is only designed for smps up to 700w


Regards Silvio

Thanks for link, however I have already xls sheets for calculating the resoant, I have however no calculator for multiply voltages like 12, 320, 120 + 120 volts.

I go just follow the simulation and use the simulated inductions. Calculate the needed copper wires and scin effect, this can be help. Now I need a supplyer
for the transformers because what I have now is from pc supply's but with unkwown specs, I have wind 10 windings and measure it getting 125 uH so this
way it works also, however when using multtply windings it wil not always be working to get the right induction s.

The program you linking here is not usable, becasue for resonant and the Q and K we need really the right power and voltage specs. For the resoant I have here there is
no need for a pfc, it is just max 250 a 300 watts.

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Hi All

Do somebody now how to calculate the transformer itselfs? I have done this with a excel sheet who is used for a sudden chip I not use But I think it will work
also because resonance is resonance right? I have imput that in a simulator and it was quite good and close. I see the resulting induction was quite low
that is a result of how I does make the Q factor of the system with the k.

Here is a test winded transformer, I did make a slotted bobine for it, measurement did let see a leak of 40 uH on 120uH primairy coil inductance.

Because I do need more voltages I do not know what happens, I have a old ferrite from a pc supply, I think it is better buy new ones, these are not so expenseive
anymore. For the resonant coil, do I need a version with the same spec,s? because to prevent things co wrong like saturation.

I have received now some controllers for the system, one has a direct mosfet drive capabillity without a drive transformer, for bigger power I like a transformer more.

So I can experiment.

View attachment 7161

see pic, Transformer is winded with wire, not the real one because I need to use strains of wire, this is just a test,


have you checked this?

I think you can use the formula in Infineon (international rectifier) application note AN-1160 page 13 and put it in Excel
The primary turn can be calculated using the formula on page 13,
Secondary turn can be calculated from the turn ratio obtained on page 9

if the inductance is too large you can grind the center leg of the ferrite core


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have you checked this?

The primary turn can be calculated using the formula on page 13,
Secondary turn can be calculated from the turn ratio obtained on page 9

if the inductance is too large you can grind the center leg of the ferrite core

Thanks for the note, I didm read that, the chip I have also now.

Mine concern was the multiply voltages I need 300 volts output, and 2 x 120 and 1 x 15 volts 10 amps.

I have some sheets to calculate also with other chips, it is the resonant frequ and such, what is the same for all.

I have now make a splitted bobine transformer, I wait now for the inductionmeter who is not yet here and go use that
for the prper windings becase I do not now the core specs, do 10 windings and measure it, but I did read somewhere that
this is not correct to use, it is never for example 1 uH per winding make it 10 uH with 100 windings it is not accurate anymore.

But oke, then I go order some transformer cores, these are not expensive. Like ETD39




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Hi all

I see I have post here a lot useless stuff, Oke, I am back because winter is coming.

I have still not yet find out how to make the smps, I have simulate a half bridge resonant because for pre stages
I need clean voltages. I have decided to use supply where the filament voltages are regulated like the 12.6 volt, or I
use a version in free loop and use analog regulators, I thank last is the best because the regulators do remove a lot
of noise. I have some software where I can calculate stuff. Because one supply is 350 volts it is above the rail voltage
for such things flyback is used.

The amp itselfs so 65 volts x 2 and 5 amps is separate.

Maybe some can give advice what to use, I think for resonance small supply for high voltage i possible need 400 volt input
voltage for efficienty, but simulating it do work on normal 310 volt dc input.