Design considerations of winding for low-voltage high-speed permanent magnet motor

The electrical frequency of high speed permanent magnet motor leads to pronounced parasitic effects, such as skin, proximity and circulating current effects. The parasitic effects result in uneven distribution of currents and the increase of the ac resistance of the winding. Ac resistance is proportional to the winding loss and the ratio of ac resistance of winding to dc resistance of winding is used to characterize the winding loss. The parameters of winding, as well as the parameters of slot dimensions of stator, will affect the degree of parasitic effects. The influences of some design parameters are analyzed in this paper.