Where is the exciter on a generator?

Exciter is a small generator, mounted on the same shaft as that of the main generator, which produces DC power for the main generator field winding. Many variety of exciters are available, but the most popular today is brushless exciter.

What is the purpose of an exciter on a generator?

A Exciter. The exciter supplies direct current to the field winding of the generator, at whatever voltage is required to overcome the resistance of the winding.

What is the purpose of a rotor in a generator?

Rotor bar voltage This equation applies to induced voltage in the rotor bars.

What is the advantage of the rotating field generator compared to the rotating armature generator?

There is an advantage of rotating field alternator over rotating armature alternator. The advantage of having stationary armature winding is that the voltage can be directly connected to load and also we can insulate the conductor.

What is rotor excitation?

10.3 AVR by Rotor Excitation Control. The exciter has its field winding (DC current) in the stator and armature winding in the rotor. In the case of an AC exciter generator, the three-phase AC is induced in the rotor winding, which is rectified using diode, thyristor, or transistor bridge installed in the rotor.

What is exciter rotor?

The exciter rotor is a component part an AC generator (or alternator) and forms part of the alternators excitation system. it is manufactured primarily from wound copper and electrical steel.

Why do synchronous generators need excitation?

Excitation in an electrical machine means production of magnetic flux by passing current in the field winding. In order to excite the field winding on the rotor of the synchronous machine the direct current is required.

What is the difference between a self excited and a separately excited generator?

In a separately excited (S.E.) machine, the field winding is connected to a separate voltage source while, in a self excited generator field winding is connected across the armature terminals (provides its exciting current) . Hence, the field winding has a large number of turns with a thin conductor.

What is exciter in synchronous generator?

The arrangement or the system used for the excitation of the synchronous machine is known as Excitation System. To excite the field winding of the rotor of the synchronous machine, direct current is required. Direct current is supplied to the rotor field of the small machine by a DC generator called Exciter.

Why is a rotating field system preferred against a stationary field in a synchronous machine?

Because you would have to draw all the power via slip rings and brush-gear and one could not generate at say 11 kV. That is why a rotating DC field is preferred and why the stator is able to generate at very high voltage levels as the insulation issues are much easier to handle.

What are the advantages of placing field winding on rotor?

The field winding of an alternator is placed on the rotor and is connected to DC supply through two slip rings. It is easier to insulate stationary winding for high voltages for which the alternators are usually designed.

Does the stator field in a DC generator rotate?

Answer Wiki. No , the stator field in dc generator doesn’t rotate. It is direction is fixed (even polarity doesn’t change). Emf is induced in armature winding placed on rotor because of cutting of flux and armature ( when we rotate the armature winding by prime mover).

What is the difference between stator winding and rotor winding?

The stator winding is highly insulated because high voltage induces in it. Whereas, the rotor has low insulation. The size of the stator winding is large for carrying the heavy current as compared to the field winding. The cooling system of the stator is good as compared to the rotor Because the stator is stationary.

What is the rotating part of a generator called?

Some OEMs such as GE refer to the rotating portion of the generator as the field. Others, such as Siemens refer to it as the rotor. Both are correct, but both have their limitations. “Rotor” is convenient because it tells us that it is a rotating component.

How does the rotor transmit torque from the motor to the stator?

The rotor transmits its torque to the stator by means of locking or synchronizing its magnetic field rotation to that of the stator. The strength of this magnetic locking is proportional to how much current we force to flow through the rotor.