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Reoccurring Error in RLC Series Circuit Problems.

  1. Nov 6, 2013 #1
    Hi All,

    In doing some practice RLC series circuit question, I have been obtaining incorrect values for active and reactive power. The magnitudes I obtain are correct however the sign of the value is not. I have attributed this to obtaining an incorrect argument for the absolute power, or computing phasors incorrectly. I have attached an image of the reasoning behind my problem solving however I must be fundamentally wrong somewhere.

    Attached Files:

  2. jcsd
  3. Nov 14, 2013 #2
    S=V.I*=(V.ejα).(I.ejβ)*= (V.ejα).(I.e − jβ)= V.I.ej(α − β) = VIcos(α − β) + j.VIsin(α − β)
    I*=conjugated electric current α=θv ; β=θv-θz ;α-β=θz
    Then S=V^2/Z.ejθz

    Attached Files:

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