Theoretical characterization of flux reversal machine in low-speed servo drives-the pole-PM configuration

This paper introduces and analyzes a flux reversal machine (FRM) configuration for low-speed (below 150 r/min) servo drives. The FRM configuration includes stator poles with three-phase concentrated coils and 2n_p alternate polarity permanent magnets per stator pole and a salient multiple-pole passive rotor. In-depth finite-element method analysis shows high torque density and less than 3% torque pulsation (through adequate rotor skewing) with sinusoidal three-phase vector control.