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Firt time post . just a quick question about magnetic gearing

  1. Oct 3, 2012 #1
    just a quick question .

    i'm thinking about building myself a vertical axis wind turbine and using the turbine to power a few lights around the house .
    my question is about using a magnetic gearing system . and will it work (produce more power than just using the base of the turbine with attached magnets above a stationary stator )

    i've drawn a quick example of what i'm thinking about (it's rough but should show what i mean)

    this was just a quick example using paint . the real thing will be using 32 neodymium magnets around the center wheel/gear and this will be the base of the tubine itself approx 1000mm/1m diameter

    the outer wheel or wheels if possible will be exacty half the center . so 500mm/.5m diameter using 16 neodymium magnets . all four gears / wheels will be mounted using a mag lev bearing system reducing friction as much possible .

    the aim is to have the three outer wheels spinning over stators

    would the extra force required to turn the turbine be too much to make this model functual or would it work
  2. jcsd
  3. Oct 3, 2012 #2
    If you get the distances right it will work but it won't transfer much torque over to the other wheels unless your using BIG magnets. If that's the case you can vary the spacing to match what you need up to a point. Getting them too close will cause your turbine to clog instead of turning smoothly.
    There is a 'sweet' spot between the maximum torque and the least clogging so you will need to be able to adjust the distances between the wheels. I've built a number of different versions of what you are attempting here over the years.

    To give you some useful advice though is to use one homemade axial wind turbine alternator being driven from the shaft wound to operate at the speed you expect the turbine to turn most of the time. It's much more efficient but if your setting it up this way to test different alternator design ideas have fun!
  4. Oct 4, 2012 #3
    thanks for the reply .
    this is more like what i'm thinking of doing

    i think i might build a small model first just to do some testing with the gear distances .
  5. Oct 4, 2012 #4
    That's about what I was visualizing from your description. I suggest using one of the driven plates at first while experimenting unless you get a whole lot of wind where you are.
    (just to save money - super magnets have become pretty expensive over the last couple of years A set I got a few years ago for a turbine alternator now cost almost 3 times as much and I spent $150 on them back then.)

    The reason for that is over the years I've found about 90% of people tend to over estimate the amount of wind they really have where they are unless they actually measure it using wind meters over time.

    To give you an example, I'm in a class 1 wind area (Wilmington NC) and we normally only get useful breezes at dawn and dusk times around here unless there is a storm or hurricane on it's way. I live inside the city limits and I can't put up a 60-100' tower to get to where the wind is actually blowing fast enough to really be really useful. The best I've been able to do so far is charging small lead acid batteries like the 2 small 12amp hour 12v versions I use on my wife's assisted bike and it normally takes 3-4 days to even do that. We just don't get enough wind here at rooftop levels or lower.

    Good luck with the project!
    Last edited: Oct 4, 2012
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