24/48 volt system

Discussion in 'Designing, building, making and powering your life' started by springtide, Feb 13, 2009.

  1. springtide

    springtide Junior Member

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    Hi all, I would like to have a 48 volt RAPS however most of the wind turbines i have looked at with low start up speeds and good power with low wind (around 200 watts at 5m/sec) are all 24 volts, can anyone tell me what would happen with the above diagram (dodgey MS paint). The turbines would be placed in similar areas but there would be times when one would be charging and the othe stationary.
    Would it work?
    Cheers forum.


    24-48.jpg[/attachment:1xupjst0]
     
  2. 9anda1f

    9anda1f Administrator Staff Member

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    Re: 24/48 volt system

    Everything you've done looks ok electrically. I can see no dead shorts and you've created two 24vdc systems strapped to your 48vdc load with the green wire. Obviously appropriate fusing and personal safety when working with the components of this complex system are important. My only question might be with regards to battery equalization between the two 24v systems. I can envision that the two banks would not be evenly charged. But I'm not up-to-speed on the consequences of "un-equalization".

    Looking forward to hearing from our forum electrical experts!
     
  3. Max E

    Max E Junior Member

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    Re: 24/48 volt system

    I have had 24v trucks that we run a 12v uhf radio off one battery, in a very short time that battery would fail.
    We had to use a 24-12 reducer.
    I think? you would have problems with equalization as suggested and have a short battery life, similar to what we had with the uhf.



    regards

    Max
     
  4. dgriffith

    dgriffith Junior Member

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    Re: 24/48 volt system

    Battery equalisation would be an issue. Cell balancers are all the rage now with lithium ion cells, but it's been a long time since I've seen one for a 12V battery.

    They will balance each bank to within a few millivolts - they hook across each set and transfer current back and forth as needed to balance. They don't transfer a huge amount ( the last one I saw for a 12V system - 15 years ago - had a 10A rating) but it's enough to keep things under control.

    If you're unlucky, internal earthing in each wind generator could cause trouble as well.
     

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