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Stepper Motor As A Generator

  1. May 5, 2014 #1
    Hello Wizards!

    I'm trying to use a stepper motor as a wind powered generator.

    I connected some resistors to one coil of the motor, and turned the motor with a drill,

    while reading the voltages.

    The power ( watts ) number I came up with seems too high.

    Am I missing something?


  2. jcsd
  3. May 6, 2014 #2


    User Avatar
    Science Advisor

    You have 14.142 VAC across A1-A3.
    You have a load of 21.6 ohm across A1-A3.
    The current is therefore ( 14.142 volt / 21.6 ohm) = 0.6547 amp RMS
    Power is ( 14.142 volt * 0.6547 amp ) = 9.26 watt

    So where did you get your 10.1 amp from ?
    Because a stepper motor produces pulses you may be reading the peak current.

    [edited to fix equation]
    Last edited: May 6, 2014
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