A fast variable structure current controller for an induction machine drive

Field-oriented control of a current source inverter induction machine system is essentially performed by controlling both the 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 DC drives, is not effective in the design of AC drivers due to this interaction. A new current loop modeling and control method is presented. This fast and robust current control technique enhances the entire system performance