Comparison of concentrated and distributed windings in an IPM machine for field weakening applications

Distributed windings produce MMF waveforms which are almost sinusoidal whereas concentrated windings produce MMF waveforms which are high in leakage harmonic content. The increase in leakage harmonic content is beneficial in meeting the characteristic current equilibrium conditions for optimization of the field weakening range. On the other hand, these additional harmonic contents also lead to an increase in iron losses especially in the wider field weakening range. This paper presents a comparative study on distributed and concentrated windings in an IPM machine. Transient - time stepped finite element analysis will be used to justify these studies.