DG Set

Hello pkmassar

It is normal for small Diesel Alternator sets to output at Mains voltage.

Larger units output at 3.3 or 6.6 kV.

Still larger units output at 11kV.

Power station Alternators output from range from 11kV to 13.6 kV approximately.

The reason is that as the internal Alternator voltage increases, the internal insulation requirements become far greater, and it is cheaper to use a step-up Transformer.

Most installations use a Transformer which increases the basic output from the Alternator to the Voltage required for transmission or distribution, at which load end, step-down Transformers reduce the Voltage to the required amount.

Transformers lose a small amount of energy, but if a fault develops they are more easily repaired, and it is normal to have one or more spare Transformers, which are easily exchanged when a fault occurs, in most installations.

The diagram below, shows the load end of a high voltage transmission line, note transformers.

Trust that helps you.

Kind Regards....