12V -> 24V Converter @ 50A...

[froggy]

12v-24v convertor

Hi, does anyone have a suggestion or schematic, how to build a 12-24V step-up converter that can deliver 50+ A?

/Froggy

 

[sick_man]

12v to 220v inverter schematic sinus

my best advice is too step too 240 and use a 50 amp variable psu

if you actualy need 50 amps 100 duty cycle then another few batteries are needed

 

[froggy]

The reason why I need this is that I have a 24V - > 240V Inverter that I want to use in a 12V system. So If I would go to 240V then I could as well skip the inverter, which I would be happy to do if I found a good schematic on a 12->240 Inverter with true sinus output. And yes I actually have a battery bank of about 550Ah to take from ...

/Froggy

 

[gulson]

froggy so You want convert twice from 12V to 24V and next 24V to 220V hmm I don't think it's a good idea..

12V DC need to change 12V AC, next to 24V AC by 1:2 transformer (very large) next use bridge, caps to get DC and convert to 220V...

no this is very wrong idea....

here is an example simple circuit to convert 12V DC to 220V AC

this is a nice UPS for computer about 100W (it's depending how big power transformer - toroidal You want to use)

some translators:
wejscie - input - 220V
wyjscie - output (here we have 220V when our electric down)
circuit with 7812 is just charge for accum and can be disabled

 

[gulson]

I haven't tested circuit with relay... I think relay is too slowly for it

 

[froggy]

gulson, No I dont want to go from 12VDC to 12VAC... I want to go from 12VDC -> 24VDC to be able to feed inverters I already have that is 24VDC->240VAC.

The reason that I want to use the inverters that I have, is that those generate high quality true sinus output , compared to the squarewave output that is generated by the example you had.

There is easy to find schematics for Inverters that generate squere, but no that easy to find reasonable simple examples that generate sinus output. And since the Inverters I have is of good quality (I took them from old UPS's) I rather prefer to use them.

/Froggy

 

[gulson]

heh so how do you want convert 12VDC to 24VDC/50Amps(!) only by transformer and for it need change to AC

 

[froggy]

Well, I thought that I could use some kind of inductor based step-up converter, so you are of course right that it's AC in a sense... but not 50/60Hz, more like 500kHz.
Maxim have like 200+ IC's that do this kind of thing, but I havn't been able to find a good AN.

I also found a extremly simple example of a converter, but I dont think that the efficency is high enough to handle 50A without burning up

/Froggy