Comparison of Unsymmetrical Two-winding Induction Motor Performances Under Variable Speed Control Techniques

The paper examines and evaluates four methods for a standard two-winding induction motor drive to achieve a wide range of speed operation with a better performance. A traditional connection of the auxiliary winding in series with a running capacitor is compared with a modified connection, the auxiliary winding without the running capacitor. To perfectly eliminate the effect of harmonic components generated by power electronic converter on the motor characteristics, the motor is supplied by sinusoidal variable voltage variable frequency source with two different control strategies. All experimental results are compared to validate the connection types, the control strategies and motor performance.