الفهرس 
Chapter (1) IntroductionOnly 14 pages are availabe for public view
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Abstract
Three phase induction motors are the most used motors as they present
80% among electric motors used in industrial application. That is because
induction motors enjoy various advantages like simplicity, ruggedness,
low cost, reliability, compactness and ease of maintenance.
Despite their benefits, induction motors have one major drawback,
which is that their speed is determined by the frequency of the supply,
and varies with torque variation. In some applications, it is required to
drive the motor with constant speed. To overcome this problem, various
speed control strategies have been formulated for the induction machine,
depending upon how the voltage-to-frequency ratio is implemented.
These methods work effectively within specific range of torque variation,
and not work effectively elsewhere.
To overcome this problem, Field Oriented Control, also called
vector control has been used in control of induction motor. It increase
torque per ampere ratio by maintaining the angle between stator field and
rotor field 900 at any load torque, which reduce the motor current and
increase efficiency and output power.
Steady state characteristics of the motor under study have been presented
. including:
Steady state starting characteristics of the motor that show
the variation of motor characteristic with speed variation
from starting to reach synchronous speed.