AC Generator – Definition and Parts of AC Generator

AC Generator

AC Generator is Alternating Current Generators. Further, this device produces emf which is an electromotive force. By increasing or decreasing the number of magnetic flux lines (lines of force) that passes through a wire’s coil.

Definition of an AC Generator

An AC generator is a device that can convert mechanical energy into electrical energy. Moreover, it works on the principle of electromagnetic induction.

Until there is relative motion present between the conductor and a magnetic field, it induces a voltage in the conductor. T\Thus, the field is that part of a conductor that produces the magnetic field.

Likewise in the armature, the voltage is induced. All generators must have two mechanical parts that are – a stator and a rotor. For the relative motion to take place between the magnetic field and the conductor.

A Rotor is that part which rotates.

A Stator is that part which that remains stationary.

In the alternators, the armature can be a rotor or a stator.

ac generator

Parts of an AC Generator

An AC generator has two poles that are the South Pole and the other one is the North Pole of a magnet. This produces a uniform magnetic field.

There is a rectangular shaped coil known as an armature. Further, the armature is connected to the slip rings and attaches itself with carbon brushes. These slip rings are made up of metallic elements and are also insulated by each other.

Similarly, one end of each carbon brush connects to the ring and the other one connects to the circuit. Rectangular coils i.e. the armature rotate through an axis that is perpendicular to the magnetic field. A shaft is also there that rotates rapidly.

Working of an AC Generator

When the armature i.e. the rectangular-shaped coils rotates between the poles of the magnet around an axis that is perpendicular to the magnet field. As a result, the flux that links with these coils continuously changes.

Hence, this process induces an electromagnetic field in the armature. This results in producing an electric current through the galvanometer and the brushes and also through the brushes.

Between the positive and the negative values the galvanometer swings. This shows that there is an alternating current that is flowing through the galvanometer.
EMF induced in an AC Generator

When the N Coil turn and the area A rotates at v revolutions/second in a uniform magnetic field B, then it produces motional electromagnetic field that is e = NBA(2πv)sin(2πv)t, where we assume this at a time of t = 0 seconds, then this coil is perpendicular to the electromagnetic field.

Lenz’s law or Fleming’s right-hand rule gives the direction of the induced electromagnetic field.

Fleming’s Right-Hand Rule

The Fleming’s right-hand rule says that, stretch the forefinger, middle finger and right hand’s thumb in a way like they are perpendicular manually to each other.

If the forefinger shows the direction of the magnetic field, the thumb indicates the direction of the conductor’s motion.

And on the other hand, the middle finger shows the direction of the current that is induced in the conductor.

3 Phase AC Generator

The symmetric three-phase power supply system has three conductors each of them carries an alternating current of the equal frequency and voltage amplitude that is relative to a common reference, but with the difference of a phase that is one third the period.

The common reference basically connects to the ground and often to a conductor that carries current and is also neutral.

Solved Question for You

Ques. What does AC stand for?

(A). Alternating Current.
(B). Active Current.
(C). Ampere Current.
(D). Aligned Circuit.

Ans. (A). Alternating Current.

Share with friends

Customize your course in 30 seconds

Which class are you in?
Get ready for all-new Live Classes!
Now learn Live with India's best teachers. Join courses with the best schedule and enjoy fun and interactive classes.
Ashhar Firdausi
IIT Roorkee
Dr. Nazma Shaik
Gaurav Tiwari
Get Started

Leave a Reply

Your email address will not be published. Required fields are marked *

Download the App

Watch lectures, practise questions and take tests on the go.

Customize your course in 30 seconds

No thanks.