Sensorless IFOC of induction motor with current regulators in current reference frame

In this paper, a new current vector control method combined with an indirect-field-orientation feedforward algorithm is presented for shaft-sensorless induction motor drives. The new current control technique is based on the concept that the angular speed and the magnitude of the stator current vector can be controlled by two stator voltage components relative to the stator current vector. In the proposed solution, the current regulators are rotating together with the stator current vector. The new topology drive has improved low-speed performance compared to the conventional solutions