Category: 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. d.c. excitation only
B. speed of the motor
C. load on the motor
D. both the speed and rotor flux

A. Periodic variation of load
B. Over-excitation
C. Over-loading for long periods
D. Small and constant load

A. d.c. source
B. armature input
C. motor input
D. supply lines

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

A. 10 per cent
B. 6 per cent
C. 4 per cent
D. 2. per cent
E. zero

A. damper winding on rotor poles
B. damper winding on stator
C. damper winding on stator as well as rotor poles
D. none of the above

A. vector sum of Eb and V
B. arithmetic sum of Eb and V
C. arithmetic difference of Eb and V
D. vector difference of Eh and V

A. its power factor may be varied at will
B. its speed is independent of supply frequency
C. its speed may be controlled more easily
D. none of the above

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