A fast variable structure current controller for an induction machine drive

Field-oriented control of a current-source-inverter-fed induction-machine drive is essentially performed by controlling both magnitude and orientation of the primary current vector. The interaction of the machine counter-EMF (electromotive force) and rectifier output voltage plays an important role in the current magnitude control. The traditional current-loop design technique, which is suitable for AC drives, is not effective in the design of AC drives due to this interaction. A novel current-loop model and a simple variable structure current-control method are presented. This fast and robust current control technique enhances the entire system performance.<>