γ-δ Transformation of PM Vernier Motor

So far two types of PM vernier motor have been proposed. One type has permanent magnets only on the rotor core, and the other is with them on both the stator and rotor core. On the latter type the proposer, who is one of the authors, previously presented its theory, in which two-reaction theory wasn't described. This paper therefore describes the definition of γ-δ axis and the voltage equation on its coordinate system.