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Permanent magnet synchronous machines (PMSMs) are popular due to their high efficiency and favorable dynamic properties. In practice, these machines often have a back-electromotive force (EMF) waveform, which deviates from a theoretically ideal sinusoid or trapezoid. In the past, current waveform shaping techniques were developed for these machines to calculate nonconventional current waveforms to reduce the torque ripple. However, in the light of global warming, energy efficiency has become more important than torque ripple in many applications. Therefore, current waveform shaping techniques can be used to focus on maximum efficiency. In this paper, a technique is presented that maximizes the efficiency of both the PMSM and the drive simultaneously. A time domain approach is used instead of the classical frequency domain approach, which allows us to include many machine aspects that had to be neglected previously, i.e., armature reaction, reluctance, zero-sequence components, and iron losses. [ABSTRACT FROM AUTHOR]

This paper describes a self-sensing control scheme based on pulse-voltage-injection for permanent-magnet synchronous machines (PMSMs). Multiple saliencies, as well as the saturation and reluctance-based coupling effects, are studied by means of analytical methods, and are proved with finite element method simulations and measurements. These phenomena cause a constant estimated error of the rotor angle, as well as periodic errors with harmonics of order 6 k. The primary saliency of the considered interior PMSM with concentrated windings is strongly dependent on the load, so that the self-sensing capability disappears at some critical operating points. In this study, the parameters of the multiple saliencies are identified based on the proposed self-sensing method. The secondary saliencies are compensated with a closed loop control structure. The effectiveness of the proposed method is confirmed by experimental results. [ABSTRACT FROM PUBLISHER]