Tranformer for DC output to battery?

Discussion in 'Windtura Generators' started by AdironDoc, Nov 11, 2010.

  1. AdironDoc

    AdironDoc WindyNation Engineer

    I have a Windblue imitation which produces 12V at 130RPM. I'd like to charge my 12V bank. Problem is, 12V drops quickly over a length of wire, and my mast alone is 34ft. Unlike the WIndBlue, I notice my unit has two output leads, and generates DC (perhaps an internal rectifier?). Moreover, a fresh 12V Battery will not turn the PMA but spinning it will easily light a bulb (internal diode?). So my problem is how to get the output 50ft or more to the charge controller and batteries. Should the output be transformed to higher voltage at the PMA to avoid losses on the way down the mast? It's a low wind area and I'd imagine my voltage without load will range from 6-24V.

  2. timber

    timber WindyNation Engineer


    Yes, if you have a car alternator type wind turbine then it is very likely that it has an internal rectifier, therefor the two wires out of the unit would be DC.

    Remember the ol' Edison vs. Telsa "War of Currents" where Thomas Edison (who had a patent on Direct Current) insisted that Direct Current was the wave of the future where Nikola Telsa (and his eventual partner George Westinghouse) argued that Alternating Current was more efficient at traveling long distances? Well Telsa was right. ( )
    DC is fine for use nearby (using heavier gauge wire) but AC will have less voltage drop over longer distances (and/ or smaller gauge wire).

    Perhaps you could remove or bypass the internal rectifier (and use 3 "down wires" instead of two) then place a 3-phase rectifier just before the charge controller then proceed as DC on to the batteries with a heavier gauge wire.)

    Using a larger gauge wire will also help to lower the resistance and reduce the voltage drop.
    I use 3 strands of 8 ga. wire to carry my 3-phase Alternating Current from my alternator down to my charge controller.
    I use a 3-phase rectifier to change the current to Direct Current, run it through my charge controller then to my batteries using 4 gauge multi-stranded copper wire. (Some might see this as over-kill but I want as little resistance (thus voltage drop) throughout my system to get the most charge to my batteries.)


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