Indirect Field Orientation Control of Induction Machine with Detuning Effect

Abstract

Field orientation control (FOC) methods of an induction machine achievedecoupled torque and flux dynamics leading to independent control of torque andflux as for separately excited DC motor, but they are sensitive to motor parametervariations. The has present work selects the indirect field orientation control(IFOC) as an effective method for eliminating the coupling effect. The resultsshow how well the drive performance has been improved by this control strategy.However, to which extent the control strategy can perform the decoupling relies onthe accuracy of the slip frequency calculation. Unfortunately, the slip frequencydepends on the rotor time constant that varies continuously according to theoperational conditions and, then, the coupling effect may again arise.This paper investigates the improvement in the performance of theinduction machine dynamics as the IFOC technique is utilized, also, itinvestigatesthe degradation in dynamic performance when the rotor resistance isdeviated from its nominal value.