DC boost converter max power ?

[bianchi77]

Re: DC boost converter max power ?

I have one big 120uH 3A inductor...could be 45KHz, will match what I need ?

[joshnz]

Re: DC boost converter max power ?

for example from 15KHz and 33uH...

where did you get that from?

[bianchi77]

Re: DC boost converter max power ?

9khz with 750uh or greater
or
10khz with 680uh or greater
or
15khz with 450uh or greater

as you can see inductor size and frequency go together also input voltage and output current

so for 47uH probably 150KHz ?

[bianchi77]

Re: DC boost converter max power ?

following this equation
what's x value ? is it 220/12 ?

[joshnz]

Re: DC boost converter max power ?

9khz with 750uh or greater
or
10khz with 680uh or greater
or
15khz with 450uh or greater

as you can see inductor size and frequency go together also input voltage and output current

Also you will need a psu that can supply at least 20 watts to be sure the boost converter has enough power.

[budm]

Re: DC boost converter max power ?

I think you should use single inductor instead of using two discrete inductors connected in series, I do not know what kind of effect when you use two discrete inductors, never seen any one using it in that manner.

[budm]

Re: DC boost converter max power ?

Well, you now have two calculators you can use for plugging the known parameters.

[bianchi77]

Re: DC boost converter max power ?

easiest option is increase oscillator frequency.

then change the inductor ?
I've tried with higher frequency but voltage drop...
but I'll try again
for example from 15KHz and 33uH...

[joshnz]

Re: DC boost converter max power ?

easiest option is increase oscillator frequency.

[bianchi77]

Re: DC boost converter max power ?

Btw, are you trying to use the boost converter for your nixie project?
http://www.dos4ever.com/flyback/flyback.html#ind1

No I don't have a nixie tube, but I change it to bulb, that's why I need more power, do you have an idea to increase the power beside changing the inductor to transformer ?

[bianchi77]

Re: DC boost converter max power ?

Probably I use a better inductor or change to flyback transformer to obtain a better power...

[joshnz]

Re: DC boost converter max power ?

i used https://learn.adafruit.com/diy-boost...the-calculator

[budm]

Re: DC boost converter max power ?

Btw, are you trying to use the boost converter for your nixie project?
http://www.dos4ever.com/flyback/flyback.html#ind1

[bianchi77]

Re: DC boost converter max power ?

I put 700uH and the voltage drop to 24V

[bianchi77]

Re: DC boost converter max power ?

At that frequency you will need 7392uH

which equation or calculator do you use ?

[joshnz]

Re: DC boost converter max power ?

At that frequency you will need 7392uH

[bianchi77]

Re: DC boost converter max power ?

any other idea for increasing current beside playing with inductor ? perhaps a transistor follower ?

[bianchi77]

Re: DC boost converter max power ?

ok thanks, I need a good inductor in one piece, since I have some inductors with some values in series, it will reduce efficiency a lot since it's connected with small pin to the other not in one complete inductor...probably between 330uH 3A and 470uH 3A will be the right value to obtain 10W 220V...not far away from now...it's RL = 7K for 215V constant...

[budm]

Re: DC boost converter max power ?

The inductor and the frequency you choose are related, so you have to choose the correct parameter.

[bianchi77]

Re: DC boost converter max power ?

Yes I have a big inductor, combine with small ones...I don't have a single 400uH 3A inductor now..
if I stay with 3KHz I will not get the Vo higher with lower RL