A. a series motor
B. an induction motor
C. an alternator
D. a rotary converter
The construction of a synchronous motor resembles____________? Read More »
Synchronous Motors A. no-load and greatly over-excited fields
B. no-load and under-excited fields
C. normal load with minimum excitation
D. normal load with zero excitation
For power factor correction, synchronous motors operate at____________? Read More »
Synchronous Motors A. Eddy current losses in the conductors
B. Iron losses in the stator
C. Copper losses in the slot portion of the conductors
D. Windage losses
E. None of the above
A. flux density
B. horse power rating
C. speed
D. all of the above
The size of a synchronous motor decreases with the increase in___________? Read More »
Synchronous Motors A. Windage loss
B. Copper losses
C. Any of the above
D. None of the above
Which of the following losses, in a synchronous motor, does not vary with load? Read More »
Synchronous Motors A. high excitation only
B. low excitation only
C. both high and low excitation
D. none of the above
In a synchronous motor, the armature current has large values for____________? Read More »
Synchronous Motors A. number of poles
B. flux density
C. rotor speed
D. rotor excitation
E. none of the above
The back e.m.f. in the stator of a synchronous motor depends on____________? Read More »
Synchronous Motors A. zero
B. unity
C. lagging
D. leading
A. reduce noise level
B. reduce the eddy currents
C. provide starting torque only
D. prevent hunting and provide the starting torque
E. none of the above
In a synchronous motor, the damping winding is generally used to______________? Read More »
Synchronous Motors A. the motor is said to be fully loaded
B. the torque generated is maximum
C. the excitation is said to be zero per cent
D. the excitation is said to be hundred per cent
