Analytical computation of stator iron losses in interior permanent-magnet synchronous machine

The design of an electric machine should be done paying attention to core losses. This paper provides an analytical computation of the stator magnetic flux density distribution in an interior permanent magnet synchronous machine and of the related iron losses. The magnetic flux density waveform in the stator teeth and its 2D distribution in the stator yoke are obtained under load condition using an original dq decomposition of the air gap flux density. Then two iron loss models are used: a harmonic model and the time-dependent Loss Surface model. The analytical computations of iron losses with the two above-mentioned models are compared to finite-element-computed iron losses in the case of a high-speed machine. The good agreement in iron loss computations validates the use of a harmonic model for computing iron losses in the design of high-speed motors.