Synchronous Machine

What are the main components for constructing any Synchronous Machine (SM)?

• armature, rotor

• armature, stator

• stator, rotor

In Induction Machines, the synchronous speed is

• equal to the motor speed

• smaller than the rotor speed

• greater than rotor speed

• greater than motor speed

In SMs, the synchronous speed is

• greater than rotor speed

• smaller than rotor speed

• equal to the motor speed

In any SM's equivalent circuit, the Xs stands for ...

For any synchronous alternator, the excitation voltage is equal to Ef= Vt ..... j Ia Xs

• plus

• minus

For any synchronous motor, the excitation voltage is equal to Ef= Vt ..... j Ia Xs

• plus

• minus

The power angle is the angle between ...

• the induced voltage and the terminal voltage

• the armature current and the terminal voltage

• the armature current and the induced voltage

While the power factor is cosine the angle between ...

• the induced voltage and the terminal voltage

• the armature current and the terminal voltage

• the armature current and the induced voltage

There exist ......... losses at any SM

Answer explanation

armature copper loss & rotational loss

For a 3-phase star/Y connection SM, the armature current is calculated as the rated power divided by ...

• the terminal voltage multiplied by square root 3

• the terminal voltage divided by square root 3

• the terminal voltage