d.c. shunt machines
d.c. series machines
d.c. compound machines
any of the above
Answer is Wrong!
Answer is Right!
The correct answer is D. any of the above.
Exciters of synchronous machines can be of three types:
- D.C. shunt machines: These are the most common type of exciter. They have a field winding that is connected to a D.C. source, such as a battery or a rectifier. The field current from the exciter creates a magnetic field that rotates with the rotor of the synchronous machine.
- D.C. series machines: These exciters have a field winding that is connected in series with the armature winding of the synchronous machine. The field current from the exciter creates a magnetic field that is proportional to the armature current. This type of exciter is used in applications where it is important to have a constant field current, such as in power generation.
- D.C. compound machines: These exciters have a field winding that is connected in shunt with the armature winding and a field winding that is connected in series with the armature winding. The field current from the shunt winding creates a constant field current, while the field current from the series winding creates a field current that is proportional to the armature current. This type of exciter is used in applications where it is important to have a variable field current, such as in adjustable-speed drives.