Abstract
This paper presents an application of a nonlinear ISMC control method combined with H-∞ control method in SPMSM robust control. ISMC control is able to attenuate matched disturbances and solves the reaching phase problem. H-∞ control was utilized as a nominal controller with SM load torque observer for reference speed tracking and for further robustification of the system in terms of minimization of load torque variation effect. Proposed control showed that it can reject both matched and unmatched perturbations and keep the system robust. Overall, the combination of two robust control methods such as ISMC and H-infinity resulted in better tracking and significantly better robustness to parameter variations and load torque variations than application of single robust control method.