Doubly-Salient Permanent-Magnet Machine with Skewed Rotor and Six-State Commutating Mode

New concepts are proposed for the design, optimization and control of doubly-salient permanent-magnet machine (DSPM). A uniform pole-width is employed in which the width of rotor pole is designed to be the same as that of the stator salient pole. This design is targeted to minimum the cogging torque. Secondly, a skewed rotor at one half of pole width is used to improve the commutation. Lastly, based on the flux-linkage of the skewed-rotor, a six-state commutating mode is used to control the motor. The feasibility of these new design concepts is validated by simulations, field analysis, and experimental results of the prototype