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Power Factor - Pratical Question

  1. Sep 23, 2009 #1
    Hey - I am trying to get a better idea regarding the notion of power factor, and power factor correction as it relates to power systems.

    Here are my thoughts (I'm looking for confirmation that my intuition is correct):

    In a power system with inductive loads, the power factor is lagging, as a result the reactive power drawn results in increased current through the transmission lines and as a result, more loses.

    Here is where I get a bit confused. Inductive loads (induction motors/generations) NEED reative power to operate. As a result, wouldn't the notion of correcting the power factor to unity result in current and voltage in phase - meaning no reactive power?

    Does the addition of parrallel capacitors in essence create o 'local' source of reative power that can alternate back and forth, as opposed to reactive power that must travel back to the 'distant' source, thus resulting in higher losses (through transmission lines)?

    Hopefully, my little confusion here is clear. Any help is much appreciated!
  2. jcsd
  3. Sep 23, 2009 #2


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    Gold Member

    Roughly, yes. The Wiki article is quite good on this one.
  4. Sep 27, 2009 #3
    Generally, the parallel capacitor banks are static source of reactive energy which shall be produced by power system as an alternative for reactive power generation in power plant via large power generators. The best location of this compensation system in the point of technical-economical view can be obtained regarding system configuration and power system study. For more information you can refer to general electrical riddle No.39 from http://electrical-riddles.com
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