Maximum Power Transfer (4.4)

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Maximum Power Transfer (4.4)

• Prof. Phillips
• February 28, 2003

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Maximum Power Transfer

• To obtain the maximum power transfer from a fixed
  source to a variable load, the load resistance
  (RL) is chosen equal to the Thevenin equivalent
  resistance representing the remainder of the
  network
• RL RTh

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Maximum Power Transfer
RTh
RL RTh

voc
RL

• What is the amount of power transferred?

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Amount of Power Transferred

• Since RL RTh, then by using voltage division,
  one can easily see that the voltage across both
  RL and RTh is half of voc
• So half of the power is dissipated in the load
• The other half is lost to the source

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Class Example