ELECTRIC POWER SYSTEMS
TEXT ASSIGNMENT -------------------- Attached memorandum.
MATERIALS REQUIRED ----------------- None.
LESSON OBJECTIVE ------------------- To teach you the characteristics
and functions of electric power
ALTERNATING CURRENT (AC) SYSTEMS
A reasonably reliable and adequate
source of electric power is always
systems first flows in one direction
around the loop, then reverses and
standards of electric power systems
regular recurring intervals.
power systems are of the alternating
from the combat areas to the larger,
To understand how this
more permanent installations in the
type of current is produced, a simple
Maximum use should be made of
two-pole generator will be described.
materials in order to save time and
a north and south magnetic pole and a
Where no existing power is
loop of wire fixed so it can rotate
between the poles (fig 2).
150 watts to 300 kilowatts are used in
As the loop
rotates between the poles a current
always be an adequate supply of power
when any one of them fails.
one direction when the first 180
degrees are being turned and in the
DIRECT CURRENT (DC) SYSTEMS
opposite direction when the next 180
under the condition of a constant
the loop cuts the magnetic lines of
force flowing from the north to the
flows in the same direction at all
south pole. When the loop reaches the
times (fig 1). Use of DC current for
90-degree point, the maximum number
of lines are being cut and the induced
current is at a maximum.