Page 785 - Basic Electrical Engineering

At the power-generating station, a number of alternators are connected in
parallel on a common busbar. The load is supplied from the busbar as shown
in Fig. 10.15. The procedure of connection of alternators to the busbar is

called synchronization. Although load has been shown connected with the
busbar near to the generators, in practise the generated power is sent to the

places of its use through high-voltage transmission lines not shown in the
figure. Synchronization refers to inter-connection of alternators with a busbar

in which a large number of alternators have already been connected. Such
busbars are called infinite busbars. These days all the generating stations as

well as all the loads are interconnected through a huge network of
transmission and distribution system. This is called the National Grid system.
Synchronization of an alternator is the connection of an incoming alternator

to the infinite busbar. A few conditions must be satisfied before a new
machine is connected to the system.

Figure 10.15 Parallel connection of alternators (synchronous generators)

10.14.3 Conditions for Parallel Connection and Synchronization

For satisfactory parallel connection of a synchronous generator to the busbar,

the following three conditions must be met:

i. The generated voltage of the incoming machine should be equal to the busbar voltage.
ii. The frequency of generated voltage of the incoming generator should be equal to the