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Calculation for power factor

  1. Jan 20, 2014 #1
    I'm trying to calculate the power factor of a three phase synchronous generator

    torque angle = arctan^-1 (impedance)
    (sin torque angle/ current x voltage)
    90 - torque angle - sin = XYZ
    power factor is cosine XYZ

    Is this the correct calculation to use?
  2. jcsd
  3. Jan 22, 2014 #2


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    Hi Idea04! :smile:
    i think i know what you mean, but that's not how to write it :redface:

    it's arctan or tan-1, not arctan-1

    and they are for real numbers, not complex numbers, you need arg for that

    impedance is a complex number, and Z = X + iY = |Z|e

    φ = arctan(Y/X) = tan-1 Y/X = arg(impedance) :wink:
    sorry, i don't understand this … eg what is the angle XYZ ? :confused:

    add the three complex voltages (as complex numbers), then find the arg :smile:
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