This paper studies the impact of current harmonics on the synchronous reluctance machine's average torque and torque ripple. The electromagnetic model of a general m-phase synchronous reluctance machine which integrates the inductance and current harmonics is developed. This model shows that there exist two mechanisms that generate an average torque with a non-zero average value: the proper contribution of the current harmonics and the interaction between them. This model is then used in the case of a 2-phase synchronous reluctance machine with a common transversally laminated anisotropic rotor. This machine design shows negligible inductance harmonics with respect to its fundamental value. Therefore, it has been found that the interaction between the 3rd and 5th current harmonics generates a torque equivalent to the torque generated by the fundamental current component. A locus of the current harmonic components that deliver a constant torque is determined. Furthermore, we have found that, on this locus, the machine torque ripple decreases significantly. Experimental data validate the developed theoretical work and show that at the same torque, the torque ripple is reduced from 20% to 4%.
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