Current control of induction motors at low speeds

Abstract

Current control of an inverter/induction motor system is considered for the special situation of a position control system where speed is low. The authors concentrate on switching-line type controllers, including the hysteresis controller, since they are simple to implement. Investigations are made of the effects of clocking the controller, injecting zero sequence into the current reference and rotating the switching lines. These modifications are shown to give significant improvements to current control for both large and small disturbances.