DC DC Converter for Wind Energy System

Discussion in 'The Projects Forum' started by kewzj, Nov 11, 2013.

  1. kewzj

    Thread Starter New Member

    Oct 30, 2013
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    0
    Hi,

    I'm currently doing a project for wind and solar hybrid controller. For the wind part, I have a wind turbine which gives a power of 1.5kW, output AC voltage of 220V. After the output voltage is rectified, the voltage have to be stepped down to 12V to enter the battery storage systems. May I know if there are any step down converter suitable for such high power and voltage? Since most of the buck converter in IC are not able to withstand such high power and voltage.
     
  2. ronv

    AAC Fanatic!

    Nov 12, 2008
    3,290
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    1500 watts at 12 volts is 125 amps. I don't know many batteries that can be charged at that rate.
     
  3. tcmtech

    Well-Known Member

    Nov 4, 2013
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    There are lots of units capable of working with that input range and power handling capacity.

    What you would be looking for is a commercial SMPS with the universal 90 - 265 or 180 - 300 VAC type input and an adjustable 12 or 15 volt output.

    For charging 12 volt batteries you would need between 13.4 and 14.8 VDC so either turning up a 12 volt unit or turning down a 15 volt unit would be reasonable choices.

    A quick look on eBay shows dozens of them to chose from in the 12 - 15 VDC 30 - 100+ amp range. ;)
     
  4. Autowood

    New Member

    Nov 9, 2013
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    AC is much easier to step down (or up) than DC. Drop the AC to 12v then rectify.
     
  5. inwo

    Well-Known Member

    Nov 7, 2013
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    In a practical application there is much more to battery charging than connecting a 12volt supply.

    What's needed is a battery charger.
     
  6. MaxHeadRoom

    Expert

    Jul 18, 2013
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    1ph or 3 ph?
    Max.
     
  7. ErnieM

    AAC Fanatic!

    Apr 24, 2011
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    That's about the worst way to do this do to the incredible inefficiency you are introducing. Even using schottky diodes your loss is .6V out of 12.6V or 4% just in the rectification.

    Best to rectify first, then convert to 12V, which of course implies using a switcher.
     
  8. poopscoop

    Member

    Dec 12, 2012
    139
    16
    I'm interested in seeing you reasoning as to why converting AC at 220V to DC, then Switching to 12v is more efficient than AC 220-->12 to DC. I haven't seen this discussed much around here.
     
  9. inwo

    Well-Known Member

    Nov 7, 2013
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    Diode voltage drops are fixed.
    At lower voltages it's a higher % loss.
     
  10. tcmtech

    Well-Known Member

    Nov 4, 2013
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    As most small wind generators do not put out a constant voltage or frequency that can cause issues with normal transformers whereas by using a SMPS based step down system the input voltage and frequency can vary greatly without the low voltage side being affected.

    Also with wind power the energy source is free so a few % being lost really isn't a concern especially if output power stability can be greatly improved.
     
    Last edited: Nov 13, 2013
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