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Reason for power companies .95 power factor?

  1. Nov 13, 2012 #1
    I tried to get a hold of an engineer for the DUKE power company out here in North Carolina to ask for the reason to their transformers only having a .95 power factor.

    In THEORY it is possible to have a 1 for the PF, and my electricity class has asked me to figure out why Duke Power co. doesn't have the perfect transformer.

    So not being able to contact Duke power, I am asking the alleged electrical engineers here at physicsforums.

  2. jcsd
  3. Nov 13, 2012 #2


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    Science Advisor
    Gold Member

    Is the 0.95 power factor "leading" or "lagging"?
  4. Nov 13, 2012 #3
    crime in Italy!

    I have no clue.

    Why would either be .95?
  5. Nov 14, 2012 #4
    Think of a transformer being a large bundle of wrapped wires. What normally leads to a power factor in a circuit?
  6. Nov 14, 2012 #5


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    Staff: Mentor

    Inductors have a lagging power factor.

    Perhaps the answer is simply that theory does not equal practice?

    I'm a mechanical engineer though...
    Last edited: Nov 14, 2012
  7. Nov 14, 2012 #6
    In theory a very thin wire can carry a very large current also. But if you wired up a power system to carry 20 amps through a 22 gauge wire you would have a problem.

    Most "in theory" questions ignore the fact current generates heat which is lost power. Among the many side effects that causes is power loss in transformers because the windings carrying the current will heat up.
  8. Nov 14, 2012 #7
    Of course it's because of the inductance, yes.

    Small tranformers are worse than 0.95, big ones are better.
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