Alternating current generators, typically referred to as AC generators, generally work on the same principle as direct current generators.The basic function of a generator is to convert motion into electricity. Providing this motion requires that either a magnetic field is generated and a wire coil is rotated within it, or a magnetic field is rotated within a stationary coil.
When the coil is rotated within an electric field, all of the electrons within the wire start to move in one direction and form a current. As the coil of wire spins, it moves across the electric field first in one direction and then in another, which changes the direction of the flow of electrons. This constantly changing nature of the current provides its name of an alternating current. This alternating current is useful because it can easily be made into a stronger or weaker current. AC current is also sent more easily over long distances. The law of physics that governs the creation of electric current within an AC generator is called Faraday's law.
The value of the voltage produced by an AC generator generally depends on three different factors: the number of turns in the coil, the strength of the magnetic field within the device and the speed at which the coil or the field rotates.