Zener regulator

Discussion in 'General Electronics Chat' started by stockcarsutty, Mar 2, 2011.

  1. stockcarsutty

    Thread Starter New Member

    Mar 2, 2011
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    I have built a Zener regulator. I am not getting the results I hoped for. I am regulating wind energy down to my 12v battery bank. how is this regulator getting rid of the extra voltage? also i need help recalculating my components. max volt 40v 30amps and wanting to charge at 14v what size components should i have?
     
  2. stockcarsutty

    Thread Starter New Member

    Mar 2, 2011
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    at least let me know if a zener regulator can limit voltage to 14v and below dependably if done right?
     
  3. Adjuster

    Well-Known Member

    Dec 26, 2010
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    Please post a schematic. It sounds likely that your zener would need to be enormously big to handle the power, but unless people can see exactly what you are doing it will hard to comment.

    Probably I'm not best placed to advise you anyway, but someone else might be - if they had a clear idea of your requirements.
     
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  4. stockcarsutty

    Thread Starter New Member

    Mar 2, 2011
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    [​IMG]

    this is the diagram of what i am doing
     
  5. stockcarsutty

    Thread Starter New Member

    Mar 2, 2011
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    maybe this type of regulator isn't made for this high of voltage??
     
  6. SgtWookie

    Expert

    Jul 17, 2007
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    If your charging system is actually putting out 40v @ 30A, and you want to clamp the battery bank at 14v, that means your clamp will have to dissipate (40V-14V)*30A = 780 Watts of power. :eek:

    Instead of a clamp, you might want to consider just electrically disconnecting the battery bank once charged, and connecting the wind generator outputs together to keep it from over-speeding.
     
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  7. stockcarsutty

    Thread Starter New Member

    Mar 2, 2011
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    how about if i lowered the amps to 15 would that make it reasonable? if not what do u recomend on disconnecting the charge electric? and would i still need to regulate it from the 40v?
     
  8. SgtWookie

    Expert

    Jul 17, 2007
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    Well, then you'd still have 390 Watts of power to dissipate in a shunt regulator.

    You might consider solid-state relays. They are not cheap, but reasonable; more reliable than relays, and require practically no power to switch on and off.

    Well, you'll need something to monitor the battery bank voltage and the available output current of the wind powered generator.

    Keep in mind that automotive batteries are not suitable for deep-cycle duty; they'll fall apart pretty quickly if you attempt to use them in that manner.

    What you might do as far as charging is to do a "bulk charge", getting the bank up to perhaps 14.2v-14.4v - and then maintaining them at ~13.6v or so as long as their is still output from the wind generator.

    Without more info on your battery bank and intended load, it's kind of hard to speculate what your needs are.
     
  9. Kermit2

    AAC Fanatic!

    Feb 5, 2010
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    You WANT all the power you can get from the generator to go to the battery bank.

    Don't limit it at all. One large diode(to prevent the battery from outputing into the wind genny) is all you need here.

    The other thing you need is a 'Dump load'. A simple voltage comparator monitors the voltage on the battery and when they are fully charged, the generator voltage is switched and sent to the dump load. This is usually just a very large resistor which absorbs the power and dissipates it as heat.

    Google seems to be working for me here. Give it a try! :)
     
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  10. SgtWookie

    Expert

    Jul 17, 2007
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    Kermit,
    A diode (even a hefty one) will drop ~1V across itself with 3A current flowing, thus dissipating about 30W power. That's why I suggested a SSR instead of a diode.

    MOSFETs might work too, but the controls will become more complex. Besides, our O.P. really doesn't need any kind of fast switching here.

    If they're really trying to get efficient about things, they could use an MPPT (maximum power point track) controller; however they'd be better off to buy one off-the-shelf rather than try to build it.
     
  11. spinnaker

    AAC Fanatic!

    Oct 29, 2009
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    Charging batteries are pretty complicated to do it efficiently. You might want to consider and off the shelf charge controller. Not sure which part of the world you are in but I just purchased a charge controller from this company.

    I have not had a chance to test ti but they get very good reviews. Their controllers even go as far as compensating for temperature changes.

    The charge controller I purchased was their smallest and it is still probably more than I need but it sure beats trying to design something.
     
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  12. ifixit

    Distinguished Member

    Nov 20, 2008
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    Hi,

    Keeping in mind what spinnaker said, is it possible to put three 12V batteries in series? That way the 40V output can charge efficiently into a 36V battery though a battery charge controller.

    Regards,
    Ifixit
     
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  13. stockcarsutty

    Thread Starter New Member

    Mar 2, 2011
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    Well i could use a bridge rectifier to keep the flow correct. but as for using all the power...
    I thought that if the batteries were low, say 11 v and the wind picked up and it put 40v to the batteries it would shorten there life?
    as for the comparator, I did not find this before so thanks!
    by the way I only YAHOOOOOOOOO!
     
  14. stockcarsutty

    Thread Starter New Member

    Mar 2, 2011
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    I dont get 40v all the time thats just prob my max.
    i would hate to waste the electric that is below 36v then which is the majority of the time
     
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