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What happens when an alternator is said to be over excited?

What happens when an alternator is said to be over excited? Correct Answer Lagging power factor

An overexcited alternator always supplies lagging current to the connected load, which means that load is of lagging nature. Lagging load take active and reactive power from the supply or alternator. Therefore, reactive power flows outwards from an over-excited alternator.

Important Points:

  • Under excited alternator works at the leading power factor
  • The normal excited alternator works at the unity power factor
  • The overexcited alternator works at lagging power factor

 

For Synchronous motor its opposite of alternator,

  • Under excited synchronous motor works at lagging power factor
  • The normal excited synchronous motor works at the unity power factor
  • The overexcited synchronous motor works at a leading power factor

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