Introduction to AC:Alternating Current Generator

Alternating Current Generator

The basic principle of an AC generator is shown in Figure 1. The coil ends are connected to two slip rings.

As the coil sides A and B are rotated by an external force side A will have an EMF induced first in one direction and then in the other direction.

As side A of the coil is permanently connected to one slip ring, this ring will alternate from positive to negative as coil side A rotates past the North and South pole faces. The same process applies to coil side B. The generated output is therefore alternating ( AC ).

The direction of the induced EMF in each coil side can be determined by the use of Fleming’s Right Hand Rule.