Abstract
This paper suggests a robust control approach for induction motor (IM) drives. The novel approach incorporates the two-degrees-of-freedom (2DOF) control scheme principle and the variable structure control (VSC) method. This highly modifies the capability of VSC scheme to suppress the influences of load torque disturbances and parameters uncertainty. Lpapunov stability concept is applied to guarantee the stability and to design the gains of VSC. A complete IM drive with the proposed 2DOF VSC scheme is assessed by simulations. The experimental system setup is executed practically by digital signal processor to apply the proposed controller. The results are provided under various 'working conditions to justify the efficacy of the suggested 2DOF VSC scheme. The 2DOF VSC approach and previous works are evaluated together under the variation of torque and speed reference. The results proved that the new 2DOF VSC scheme has significant dynamic performance with high suppression of disturbances and parameters mismatch in comparison to 1DOF and 2DOF control schemes.