An improved two-stage control scheme for an induction motor

In this paper, an improved two-stage control scheme (previously developed by the authors) is presented. A slip-frequency controller operates together with a current-magnitude controller to yield the desired values of current and frequency during the acceleration/deceleration stage and the steady-state stage. Simulation studies on a 7.5 kW induction motor are performed using Matlab/Simulink. The simulation results indicate that the performance of the two-stage control scheme is comparable with that obtained using field-oriented control. Besides, the improved control scheme is much simpler to implement and the performance is less sensitive to machine parameter changes.