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Power factor of transformer

  1. Jan 8, 2015 #1
    In a transformer , we know that the no-load current has two components , one magnetizing component I0sinphiand other one is the winding loss component i.e. I0cosphi..
    if the magntizing current increases in the transformer what is the effect on the power factor??
  2. jcsd
  3. Jan 8, 2015 #2


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    How can the magnetising current increase without there also being a change in the resistive losses ?
  4. Jan 9, 2015 #3
    In my opinion, the magnetizing component of no-load current could increase dramatically if the supply voltage will increase over the laminate saturation point. The laminate losses will increase in a moderate way only. So, in this case the power factor could decrease more. The copper resistance and the magnetic field leakage reactance did not cooperate more in order to change the power factor.
  5. Jan 9, 2015 #4
    Yes , you are right the power factor will decrease .. Actually we can analyse it from the phasor diagram of transformer at no-load.. if Im (magnetizing current) increase , the phase angle will increase , so consequently power factor will decrease..!!
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