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    High Input Current DC-DC Converter?

    I am looking for a DC-DC converter design with the following specifications.

    Vin = 24 V
    Iin = 135 A

    Vout = 60 V
    Iout = 50 A

    Which topology will work in this case? Any design or schematic?

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    Re: High Input Current DC-DC Converter?

    If isolation required, LLC converter, otherwise multiphase synchronous boost.



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    Re: High Input Current DC-DC Converter?

    current fed push pull is a good option too at low vin - keeps the current in the devices to low levels - splitting into 2 converters will assist greatly too ...

    - - - Updated - - -

    also - for non-isolated two interleaved boosters will work very nicely ...



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    Re: High Input Current DC-DC Converter?

    To follow up on the above suggestions, here's a simulation of quadruple interleaved boost converter. 24V supply stepped up to 60V 50A.

    Click image for larger version. 

Name:	quadruple boost converter clk-driv 24V supply load gets 60V 50A.png 
Views:	9 
Size:	63.7 KB 
ID:	156605

    As you can see it requires much greater supply current than your spec 135 A.

    It's important to reduce all parasitic resistance.



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    Re: High Input Current DC-DC Converter?

    respectfully, the 26 milli-ohm res has 474 watts for 135 amps only, each of the diodes has 8 watts for every 10 amps thru - so the losses mount up for non ideal components

    - - - Updated - - -

    the numbers given at top imply a 92.5% eff which should be possible with synch rect boost diodes/fets - splitting into 4 phase shifted units of 34 amps each - ave ...

    - - - Updated - - -

    [ the 26 milli-ohms shown actually drops the Vin by 6.7V and consumes 1730 watts dropping the eff to 50% - better to have 4 x 0.026 ohm R's I'm thinking ]


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    Re: High Input Current DC-DC Converter?

    Quote Originally Posted by Easy peasy View Post
    the numbers given at top imply a 92.5% eff which should be possible with synch rect boost diodes/fets - splitting into 4 phase shifted units of 34 amps each - ave ...
    You are correct. Synchronous type is more efficient and was the type recommended above. I kept my simulation simple by making it asynchronous, with diodes.



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    Re: High Input Current DC-DC Converter?

    The only way to properly decide, is to delve into app notes and data sheets from major semiconductor manufacturers.
    Lots of reading, my friend.

    When you find something similar to what you are looking for, these manufacturers will always include powerful simulation software and -for the real thing, demo boards you can perform real world experiments.

    Both these tools allow you to experiment and modify the circuit, to meet your individual requirements.
    You may find that certain parameters will be difficult to meet within the allowed budget constraints, and that is when the real fun begins
    My batteries are recharged by "Helpful Post" ratings.
    If you feel that I've helped you, please indicate it as a Helpful Post



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