Effect of armature reaction on the core losses of the permanent magnet synchronous motor

Traditionally, the core losses of permanent magnet synchronous motors are assumed to vary as a function of rotational speed and the supply voltage. In this paper, the effect of armature reaction on the core losses under constant speed and stator voltage is studied. The load angle of the machine is varied, and the core losses are determined using the finite element analysis. To explain the core loss results, the flux densities with harmonic analyses in different parts of the machine are studied and discussed. It is found out that armature reaction should be taken into account if a high-accuracy core loss prediction is required.