How is the frequency output in a generator determined?

The frequency output of a generator is fundamentally linked to the number of poles in the generator and the speed at which the rotor rotates. This relationship is described by the formula:

Frequency (in hertz) = (Number of poles × Rotor speed in revolutions per minute) / 120.

This formula highlights how both the physical characteristics of the generator (the number of poles) and its operational parameters (rotor speed) play crucial roles in determining the frequency. As the rotor speed increases or the number of magnetic poles changes, the generated frequency will also vary accordingly.

Considering the other options, the type of fuel used may affect the power output and efficiency of the generator but does not directly influence the frequency output. The size of the generator refers to its physical dimensions and capacity, which again does not impact the frequency directly. Lastly, the load on the generator—while it affects electrical output and performance—does not determine the frequency; instead, it is a function of the generator’s design and operational parameters.