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Homework Help: Transformer Line/Load ratio

  1. Apr 7, 2015 #1
    1. The problem statement, all variables and given/known data
    (in picture)

    2. Relevant equations

    3. The attempt at a solution
    So last time I had to do KCL to find voltages, so I want to make sure I'm doing this one right. Can I do voltage division and do Vload/VG?

    My division would be VG(500<36.87)/(500<36.87 + 60<53.13)

    But that approach seems incredibly simply when normally, these problems have some more work involved . . .

    Attached Files:

  2. jcsd
  3. Apr 7, 2015 #2


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    It's an early problem in the chapter, so it is probably just that simple to provide voltage division across the load. Confirm you don't need to use complex conjugate for power across load.
  4. Apr 7, 2015 #3
    Really? So I got VL as 11.83<-1.726. The ratio is a complex number, but the real part is 0.89 . . . That seems incredibly good? Is it too good?

    And for the second part of the question (distribution losses), I'm assuming V^2/R over the Zline component, ignoring the "imaginary" portion of the impedance because it's power losses . . .
  5. Apr 8, 2015 #4


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    Your answer looks correct to me. And it looks good. It is supposed to look good. The low losses are due to the low resistance of the power lines (delivery system) of the grid. Power lost on the line doesn't get metered and sold.
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