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Linear Permanent Magnet Generator

  1. Sep 5, 2003 #1
    What is the most efficient way to build a permanent magnet linear generator--AC or DC, it makes no difference. I'm working on a personal project but don't know where to start. I'm assuming that a generator similar to the one inside of a ForeverFlashlight is probably the best way to go, but I'm not real sure, so I'm asking.
  2. jcsd
  3. Sep 5, 2003 #2


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    Greetings !

    Frankly, I don't know what a ForeverFlashLight is
    but it probably uses a permanent magnet and a coil
    with one of them moving (probably when you shake the thing ?),
    an AC/DC converter and an accumulator.

    In a car for example, a conducting loop is
    turned between the poles of a permanent magnet thus
    producing an AC in the loop (which you can then of course
    transfer into whatever "form" you like depending on the
    purpose of your generator, like DC to charge your accumulators).

    The circuilar motion of the loop is of course due to
    the chemical energy of the internal combustion reaction
    in the car's engine which is transferred into mechanical
    energy of the turning loop which, in turn, converts it into
    electrical energy (abviously though, in a car most of that
    mechanical energy is used to turn the wheels and thus
    increase the kinetic energy of the car or maintain it since
    energy is constantly lost to friction with the road and air resistance [zz)] ).

    Live long and prosper.
  4. Sep 5, 2003 #3
  5. Sep 5, 2003 #4


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    Wasn't it induction ? Or did they just decide to skip
    the whole story for the average buyer...
    I suppose that someone spending that much on that thing
    wouldn't know the difference...
  6. Sep 5, 2003 #5
    Haha, yeah, I never bothered to read the article 'cause I was trying too much to find a close-up image of the thing.
  7. Sep 5, 2003 #6
    Thats a cool flashlight! It has an LED instead of a bulb, and I think it has a capacitor instead of a battery.
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