Physical Concepts of Synchronous Machine Operation

Floating of synchronous machine on infinite bus means

Reactive power flow in synchronous machine can be controlled by

To start the synchronous motor, its field winding should be

If the synchronous machine is loaded from floating conditions, the synchronous motor begins to operate at

If the synchronous machine is loaded from floating conditions, the alternator begins to operate at

During the starting of the 3-phase synchronous motor by damper bars, the field winding is usually short circuited so that starting torque is equal to

Squirrel cage bars placed in the rotor pole faces of a 3-phase alternator help in reducing hunting
I. above synchronous speed
II. below synchronous speed
III. at synchronous speed

The reactive power in synchronous machine is proportional to

At steady state operation in a 3-phase synchronous generator

Active power in synchronous machine is proportional to

If the field poles are ahead of resultant mmf, then the 3-phase synchronous machine is operating as

The power load angle characteristic as maximum for a load angle of

A poly phase synchronous motor will be used for the load of ______ over poly phase induction motor.

For running a 750 kW compressor, a synchronous motor is preferred because of
(i) lower noise
(ii) faster build up of pressure
(iii) better power factor
(iv) low starting torque

If the 3-phase alternator has 4 poles and has synchronous speed of 120 rad/s.
Then the mechanical speed in rad/sec is