Abstract:
Induction motors (IM) are the most widely used electrical motors due to their reliability, low
cost and robustness. The need for variable speed of an induction motor arises in certain
industrial applications and this is often difficult to achieve because induction motors are of
fixed speed. The objective of this thesis to study the methods of improving speed range and
characteristics of an induction motor.
In this study, firstly the electric statics of IM, which affect characteristics and linearity, have
been studied.
Secondly,the characteristics for several methods of speed control of an induction motor such
as , variable rotor resistance, variable stator voltage, constant V/f control methods was
represented using MATLAB programming.
Finally, the results of closed loop constant v/f control with variable speed drive and
proportional–integral controller was obtained by MATLAB/SIMULINK, and dynamic
IV
response was represented and analyzed, which was found to match the characteristics
available in literature of speed control of induction motors.
