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    Transformer Less Inverter dc/dc

    I'm looking for help building a simple solar PV DC/DC converter.
    variable 24-60v dc to 220v 3000W+ to drive a resistive load (heat element)

    Transformer Less Inverter using a power MOSFET or two and MTTP if possible.
    cost is important.

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  2. #2
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    Re: Transformer Less Inverter dc/dc

    Search EDABoard forum you can find some solutions for that.

    In your case at least one ferrite should be used, to raise voltage. See one example:

    http://danyk.cz/menic230_6_en.html


    If you have many solar cells in serie to form high input voltage of 325V+ DC you can use H-Bridge, this is true transformeless system.


    Best regards,
    Peter
    “Let the future tell the truth, and evaluate each one according to his work and accomplishments. The present is theirs; the future, for which I have really worked, is mine.” Nikola Tesla



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  3. #3
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    Re: Transformer Less Inverter dc/dc

    Quote Originally Posted by tpetar View Post
    Search EDABoard forum you can find some solutions for that.

    In your case at least one ferrite should be used, to raise voltage. See one example:

    http://danyk.cz/menic230_6_en.html


    If you have many solar cells in serie to form high input voltage of 325V+ DC you can use H-Bridge, this is true transformeless system.


    Best regards,
    Peter
    Thanks Peter,
    I really have no experience with power circuits, so thank you for your understanding...
    I believe the above circuit is overkill? if I where to use a IGBT (mosfet) 80A at 1200V (or similar)
    all i need is Absolute Maximum Voltage: 250V DC, Abs Max Current: 20A
    solar panel wattage, Around 440W / 48V (2 x 24V)

    to power a heating element: Standard 240/208V 4500/3380W Resistive loads only.

    the issue I have would be the Schottky diode I don't think exists? 200V+ 300A !?@!
    and an inductor of similar value? is this what you mean by 'ferrite'?



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  4. #4
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    Re: Transformer Less Inverter dc/dc

    Does your heating element need AC or DC, or doesn't it matter?

    You do realize I hope that no circuit will deliver 4.5KW from a 440W source unless you have a large battery storage and the 440W is available for much longer than the load has to be fed.

    Brian.
    PLEASE - no friends requests or private emails, I simply don't have time to reply to them all.
    It's better to share your questions and answers on Edaboard so we can all benefit from each others experiences.



  5. #5
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    Re: Transformer Less Inverter dc/dc

    3KW-4KW is not smart for 24V system, you need at least 48V-72V for input.

    In all designs, solar,..... always look to use lower current, and needed power can be reached if you increase voltage.

    In any case your heater device should receive needed current and voltage according to manufacturers recommendations.

    Posted circuit is like one example, which can be adjusted or just to give some idea for your thinking.

    Can you define "transformeless" and what you expect from design to use some ferrite core or iron core or none ?



    Best regards,
    Peter
    “Let the future tell the truth, and evaluate each one according to his work and accomplishments. The present is theirs; the future, for which I have really worked, is mine.” Nikola Tesla



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