What Is A Generator?

An electrical generator is a machine which converts mechanical energy into electrical energy. The energy conversion is based on the principle of the production of dynamically induced electro-magnetic field. Whenever a conductor cuts magnetic flux, dynamically induced electro-magnetic field is produced in it according to Faraday's laws of Electromagnetic Induction. This electro-magnetic field causes a current to flow if the conductor circuit is closed. Hence the basic essential parts of an electrical generator are:

a)a magnetic field
b)a conductor or conductors which can so move as to cut the flux.

An actual generator consists of the following essential parts:
a)Magnetic frame or yoke
b)Pole cores and Pole shoes
c)Pole coils or field coils
d)Armature core
e)Armature windings or conductors
f)Commutator
g)Brushes & bearings

Of these, the yoke, the pole cores, the armature core and air gaps between the poles and the armature core form the magnetic circuit whereas the rest form the electrical circuit.