Importance of "constant frequency" in electric power generation

Many of us know that, in electrical power generation the frequency must be kept constant for satisfactory operation of power system. But, the question is, why the frequency is to made constant?
Before this, let us first understand the basic operation of the alternator.

Operation of alternator:

An alternator (synchronous generator) is a machine which converts mechanical energy into electrical energy at a particular voltage but at a constant frequency.
The rotor part consist of field winding and stator part consist of armature winding. The field winding is excited with D.C supply. The turbine is mechanically coupled with the rotor to give the mechanical power input to the alternator.

Importance of "constant frequency" in electric power generation

Now, when rotor rotates the flux due to field winding cuts armature conductors and according to the faraday's law of electromagnetic induction, an emf is induced in the armature conductors. The frequency of induced emf is given by:

So, to generate constant frequency, the machine must always be driven at constant speed.

Importance of constant frequency generation:

In order to have the understanding between Generator's and the consumer (i.e load), the standardization of frequency is essential.
All the generating stations are interconnected through grid (that is nothing but the parallel operation of the alternators). Hence, the necessary condition for the parallel operation of alternators is that there frequency must be same.
Most of the loads connected to the grid are industrial types and uses induction motors for their operation. Now, the speed of induction motor depends on the frequency of supply mains. Hence, if frequency is not maintained constant then the operation will be affected.

This are the important reason's due to which the frequency of A.C power generation is to be kept constant.

I hope you have got some good and relevant information from this blog.

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Want to know more:

1) synchronous generator vs induction generator

https://basics-of-electricalengg.blogspot.com/2021/03/Synchronous%20generator%20Vs.%20Induction%20generator.html

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