A novel stability improvement method for V/F controlled induction motor drive systems

For a V/F controlled induction motor drive system, the instability problem of sustained oscillations has often been experienced in light load state. This paper analyzes the relationship between the oscillations and the fluctuation of reactive currents and then proposes a method to improve the stability of conventional V/F control algorithm. This paper contributes to the solution of this problem based on a current feedback method. The method is implemented by adjusting the output voltage according to the fluctuation of reactive current. Experiments have proven that oscillations could be suppressed regardless of the motor type or speed. This stabilizing control method is suitable for various types of motors general-purpose driving systems.