Control philosophies of PWM inverter-fed induction motors

In this paper a review of control methods for high performance PWM inverter-fed induction motor drives is presented. Starting from the description of an induction motor by the help of the space vectors, three basic control strategies are discussed. First, the most popular field oriented control (FOC) is described. Secondly, the direct torque and flux vector control (DTFC) method, which-in contrast to FOC-departs from idea of coordinate transformation and analogy with the DC motor, is briefly characterized. The last group is based on feedback linearization control (FLC) and can be easy combined with sliding mode control. The simulation and experimental oscillograms that illustrate the performance of the discussed control strategies are shown.