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If we change the excitation of synchronous machine will it affect on power factor?

1 Answer

Yes, If we change the excitation of synchronous machine it will affect on power factor. If the synchronous motor is overexcited then it will have leading power factor and if the motor is underexcited then it will have lagging power factor.

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Description : If we change the excitation of synchronous machine will it affect on motor speed?

Answer : No, If we change the excitation of synchronous machine it will not affect on motor speed.

Answer : Yes, we can make the power factor of synchronous motor leading by adjusting its excitation.

Description : If the load of the normally excited synchronous motor is increased the power factor will?

Answer : If the load of the normally excited synchronous motor is increased the power factor will become lagging.

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Answer : If the field of synchronous motor is under excited, power factor will be lagging.

Answer : Synchronsizing power of a synchronous machine is inversely proportional to the synchronous reactance.

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Description : what will happen when excitation of an unloaded salient pole synchronous motor suddenly gets disconnected?

Answer : When excitation of an unloaded salient pole synchronous motor suddenly gets disconnected the motor will stop.

Description : A synchronous motor has better power factor as compared to that of an equivalent induction motor. This is mainly because?

Answer : A synchronous motor has better power factor as compared to that of an equivalent induction motor. This is mainly because stator supply is not required to produce magnetic field.

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

Answer : For power factor correction, synchronous motors operate at no-load and greatly over-excited fields.

Description : How can we improve power factor using synchronous motor?

Answer : A synchronous motor running with normal excitation adjusts to load increases essentially by increase in armature current.

Answer : In two part tariff, variation in load factor will affect operating or running charges.

Description : In a synchronous generator if the excitation increased from a low value to normal value, with a fixed load  (A) The armature current increases and the power factor decreases  (B) The armature ... but is lagging  (D) The armature current decreases and the power factor increases and is leading

Answer : In a synchronous generator if the excitation increased from a low value to normal value, with a fixed load The armature current decreases and the power factor increases and is leading

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Answer : In a synchronous generator delivering lagging power factor load the excitation emf leads terminal voltage by the power angle

Description : The power factor angle and torque angle of a salient pole synchronous generator drawing a current of 1.0 pu from a lagging load are 45o and 15o, respectively. The direct axis and quadrature axis currents, respectively, are (A) 0.5 pu ... pu, 0.5 pu (C) 0.707 pu, 0.707 pu (D) 0.5 pu, 0.5 pu

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Answer : In a distribution system, in order to improve power factor, the synchronous capacitors are installed at the receiving end.

Description : Can a synchronous condenser improve power factor?

Answer : Yes, synchronous condenser can improve power factor.

Description : The effect of increasing load on a synchronous motor running with normal excitation is (A) Increase both its Ia and power factor. (B) Decrease Ia, but increase power factor. (C) Increase Ia, but decrease power factor (D) Decrease both Ia and power factor.

Answer : The effect of increasing load on a synchronous motor running with normal excitation is Increase Ia, but decrease power factor

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Answer : DC shunt machine is the exciter of synchronous machine.

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Answer : In a synchronous machine, if the field flux axis ahead of the armature field axis in the direction of rotation, the machine is operating as synchronous generator 

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Answer : The synchronous motor will develop maximum power when the load angle is 900.

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Answer : 1

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