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Power transmission via Transformer.

  1. Mar 8, 2013 #1
    In transmission lines the the voltage is stepped up to a specified level thereby reducing current to ensure its transmission with minimal power loss.
    But we know that P=V*I
    so by increasing the voltage wont Powerloss gets increased?
  2. jcsd
  3. Mar 8, 2013 #2
    The powerloss doesn't depend on the voltage delivered to the load, but on the voltage across the conductors of the transmission lines, this voltage depends on their resistance and the current through them. V_loss = I * R, and the powerloss will then be P = I * V_loss = I^2 R. So decreasing the current will decrease the losses, and increasing the voltage delivered to the load won't affect the powerloss at a..
  4. Mar 8, 2013 #3


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    Staff: Mentor

    The V in that equation refers to voltage drop, not line voltage.
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