Synchronous Motors

A. the armature current is maximum
B. the armature current is minimum
C. the armature current is zero
D. none of the above

A. Damper winding
B. Star-delta starter
C. Damper winding in conjunction with star-delta starter
D. Resistance starter in the armature circuit

A. one-third
B. twice
C. thrice
D. six times
E. nine times

A. a higher value of stability limit
B. a small value of inherent regulation
C. a higher synchronizing power which makes the machine less sensitive to load variations
D. all of the above

A. voltage rating
B. current rating
C. power factor
D. speed

A. Stator flux
B. Pull in torque
C. Both A. and (b)
D. None of the above

A. carbon or graphite
B. brass or steel
C. silver or gold
D. copper or aluminium

A. synchronous motor has no slip
B. stator supply is not required to produce magnetic field
C. mechanical load on the rotor remains constant
D. synchronous motor has large airgap

A. not-self starting
B. self-starting
C. essentially self-starting
D. none of the above

A. direcly proportional to the synchronous reactance
B. inversely proportional to the synchronous reactance
A. equal to the synchronous reactance
D. none of the above