To increase the voltage

To increase the voltage

To meet the increased power demand

Top minimise the current

Frequency must be same

Frequency must be same

Rating must be same

Phase sequence must be different

Out put voltage of alternators must be different

Out put voltage of alternators must be different

Voltage of incoming alternator must be more

Incoming voltage of alternator must be less

Frequencies of machines are different

Frequencies of machines are different

Speed of alternators are same

Out put voltage of alternators are same

To start the alternator

To stop the alternator

For synchronising of alternators

To change the excitation