Stability Improvement of V/Hz Controlled PWM Inverter-fed Induction Motors Drives

Three-phase induction motor drive systems driven by V/Hz controlled PWM voltage source inverter, which have been widely used in the industrial applications, have often suffered undesirable sustained oscillations in the light loaded state and in the low frequency range. In this paper, we propose a new method which is effective and simple to improve the stability of V/Hz controlled induction motor drives. This method is robust, regardless of the parameters of the motors, the inverters and the operating conditions, and is suitable for general-purpose induction motor drive systems. Simulation and experimental results are presented to verify the validity of this proposed stabilizing control method