SPEED CONTROL OF THREE-PHASE INDUCTION MOTOR USING BUCK CHOPPER

Induction motors are widely used in industry and the need for better control of these motors with minimal harmony and distortion is growing every day. In this paper, a practical method is proposed for speed control in induction motors. To control the speed of induction motors, the rotor resistance control method has been investigated. It will be shown that the structure of the Buck chopper in the rotor of induction motor can be considered as a solution to control the rotor resistance. In the proposed method, by using IGBT in Buck chopper, a variable resistance is produced. Then, this variable resistance is employed in the rotor to control the speed. Simulations have been performed and after ensuring validity of the method, the high power Buck chopper was built.