Rotor Field-Oriented V/f Drive System Implementation with Oscillation Suppression Compensator in Induction Motors

Unlike a sensorless vector drive, because a volts per hertz ( $V/f$ ) drive has a simple controller structure, this drive is extensively used for low-cost drive markets that target applications, such as fan, pump, and blower drives, which do not require high performance. For an induction motor’s $V/f$ drive system, a voltage boost enables correct flux excitation. Moreover, to decrease the steady-state speed error, slip compensation is required. Furthermore, an oscillation suppression compensator (OSC) may be added to improve the system’s stability and dynamic performance. In this article, a rotor field-oriented $V/f$ drive implementation is presented. Both voltage boost and slip compensation strategies based on rotor field orientation are introduced, and a novel OSC design and stability analysis are presented with the numerical analysis of the root locus and stability surface. Finally, regarding the various practical situations of the induction motor, the proposed $V/f$ drive system’s effectiveness is confirmed by simulations and experiments.