New relation to improve the speed and torque characteristics of induction motors

Abstract

Squirrel cage induction motors are employed in a wide variety of applications. Operating at constant speed is required in some applications, whereas variation of this parameter is required in others, as in the provision of mechanical energy to electrical vehicles. The performance of an electric vehicle is specified by the characteristics of the electric motor. The adequate relation between the voltage magnitude and the frequency of its power source makes the motor satisfy the electric vehicle requirements. The voltage magnitude is a function of the frequency of operation. If the V - f relation is adequate, the motor speed response could be improved. A new V - f relation that improves the speed response of the single squirrel cage induction motor is presented and is defined by a frequency factor. For motor speeds below the nominal value, the torque capacity of the motor is preserved with the proposed relationship.