Page 35 - Practical Power System and Protective Relays Commissioning

Chapter 4

Generators and Motors: Theory

and Testing

4.1 INTRODUCTION
In this chapter we will explain the theory of generators, types, circuit analy-
sis, standard ratings, main components, synchronizations, connections and
installation, and the appropriate testing commissioning procedures.

4.2 GENERATING STATIONS

There are different types of generating stations. These generating stations are
classified according to the fuel that is used.

4.2.1 Hydro Power Stations

In these generating stations, electricity is produced by water flowing through
a turbine that drives an electrical generator. The amount of power produced
is proportional to the water head or height of reservoir. The turbine of this
machine has a slow speed of 100 250 revolutions per minute (rpm). This
machine can produce electricity within a few minutes of startup, which is
advantageous for supplying peak loads.

4.2.2 Thermal Power Stations
Thermal power stations generate power from the burning of fuel such as
coal, oil, or gas, in boilers of steam generators. Steam generators run at high-
er speeds of 3000 3600 rpm at 50 60 Hz.
Gas turbine stations also fall into this category. Additionally small size
units powered by diesel engines do exist.

4.2.3 Nuclear Power Stations

Nuclear power stations are similar to steam power stations but the heat nec-
essary to change the water into steam comes from the nuclear reactor.

Practical Power System and Protective Relays Commissioning.
DOI: https://doi.org/10.1016/B978-0-12-816858-5.00004-6 31
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