Why synchronous machine is called doubly excited machine?

Why synchronous machine is called doubly excited machine?

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2 Answers

Answer :

The synchronous machine is called doubly excited machine because in synchronous machine both stator and rotor are excited.

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Answer :

Armature windings of synchronous machines either deliver 3 phase AC or absorb 3 phase AC source,  whereas field windings are energized from DC source. Thus due to presence of AC on armature and DC on field windings, synchronous machines are often referred as doubly excited machines.
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Related questions

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Separately Excited DC motor

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Last Answer : The standard full-load power factor ratings for synchronous motors are unity or 0.8 leading.

The operating speed of a synchronous motor can be changed to new fixed value by?

Last Answer : The operating speed of a synchronous motor can be changed to new fixed value by changing frequency.

A synchronous motor can develop synchronous torque?

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In case one phase of a three-phase synchronous motor is short-circuited the motor will?

Last Answer : In case one phase of a three-phase synchronous motor is short-circuited the motor will not start.

Synchronous motors are generally not self-starting because?

Last Answer : Synchronous motors are generally not self-starting because the direction of instantaneous torque reverses after half cycle.

In a synchronous motor, the armature current has large values for?

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The size of a synchronous motor decreases with the increase in?

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The maximum constant load torque under which a synchronous motor will pull into synchronism...

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The construction of a synchronous motor resembles?

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For power factor correction, synchronous motors operate at?

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If the synchronous motor, properly synchronised to the supply is running on no load and is having negligible loss then?

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The damping winding in synchronous motor is generally used to?

Description : The damping winding in synchronous motor is generally used to?

Last Answer : The damping winding in synchronous motor is generally used to provide starting torque and prevent hunting.

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Description : An unexcited single phase synchronous motor is ?

Last Answer : An unexcited single-phase synchronous motor is reluctance motor.

A synchronous motor can be made self starting by providing?

Description : A synchronous motor can be made self starting by providing?

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In a synchronous motor which losses varies with load?

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The back emf of synchronous motor depends on?

Description : The back emf of synchronous motor depends on?

Last Answer : The back emf of synchronous motor depends on load angle.

Synchronous motor always runs at which speed?

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Last Answer : Synchronous motor always runs at synchronous speed.