Comparative Study on Torque Ripple Reduction Considering Minimum Losses for Synchronous Reluctance Motor Drives

This article deeply investigates the torque ripple reduction of synchronous reluctance motors (SynRel), considering the impact of the current harmonic injection (CHI) on the total losses by employing d-, q-, and dq-axes injections. An in-depth analysis of the torque behavior has been carried out by means of finite element (FE) simulations, highlighting the dependence of the torque ripple on the magnetic saturation. The current reference trajectories are derived based on the torque ripple model taking into account the magnetic saturation, while the total loss is minimized by considering the copper and iron losses by the FE-based or experimental evaluation to select the optimal solution. The effectiveness of the torque ripple reduction technique using different CHIs is demonstrated by the FE simulations and experiments for the SynRel 15-kW prototype.