ABSTRACT
Vernier reluctance machines were apparently introduced in 1960, while their PM versions have been developed since 1995. Vernier PM machines are characterized by larger torque density and higher efficiency in low-speed drives. Being a flux-modulation machine (Chapter 1) with an open-slotted stator, with its slots containing a distributed (q > 1) winding with pa pole pair mmf and 2pr PM-rotor poles, the two conditions for nonzero average torque (and synchronous operation) are (Chapter 1). Fundamentally, the first harmonic of the flux modulator (the slotted stator airgap magnetic permeance of Ns periods per the entire periphery) “couples” the rotor-PM mmf pr pole pair mmf with the armature AC winding pa pole pair mmf.
