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Power Factor Correction

  1. Feb 6, 2014 #1
    When you connect a capacitor across an inductive load, reactive power (Q) flows back and forth between capacitor and inductor, so (ideally) the generator doesn't need to supply Q to the load.

    My question is, why doesn't the capacitor supply Q to the generator as well? If only a capacitor were connected across a generator, Q would flow from capacitor->generator and vice versa. But when an inductive load is also connected in parallel, Q flows only b/w cap. and ind. and does not go towards the generator. Why is this so?
  2. jcsd
  3. Feb 6, 2014 #2


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    Staff: Mentor

    The generator supplies the capacitor with reactive power (leading), and it supplies the inductive load with lagging reactive power. There is some cancelling of the leading with the lagging, so the generator ends up supplying less reactive power than when supplying the inductive load alone.
  4. Feb 9, 2014 #3
    Got it, thank you.
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