This paper proposes fuzzy logic controller based speed control of a three phase induction motor. The system is modeled in a MATLAB simu link and the result is being compared with the conventional PI controller. Constant v/f control scheme is being implemented in the scheme. The controller is designed such that it can reduce the error between rotor speed and reference speed as fast as possible. the performance of the controller with the change in reference speed is simulated and the dynamic performance of the motor is observed. Result show that the dynamic performance of the induction motor is improved. Along with that result shows that the system is not much affected to the disturbance occurring in the system. The induction motor attains adaptability to the system disturbances which proves to be very useful for the robust performance of the motor.

Keywords : Fuzzy Logic Controller, Three Phase Induction Motor, Fuzzification, Constant V/F Control.