Closed loop harmonic content reduction for three phase induction machines control

This paper presents a closed loop control technique for harmonic content reduction in the stator current of an induction machine feeded with a three phase inverter, within a velocity control loop. Using a digital filter for Clarke transformation, a robust sliding flux observer, and a closed loop control for the zero sequence of a SVPWM three phase inverter, this work shows how the proposed schema can effectively reduce the harmonic content in the stator currents of the induction machine despite of variations on the load torque using just two sensors: a current sensor for one of the stator phases and a velocity sensor for the closed loop control of the velocity of the machine.