Modelling of surface PM machine using soft magnetic composites and a bonded magnet ring

Abstract

This paper examines the modelling of a 1.6 kW, 3,000 rpm surface permanent magnet machine which was constructed using soft magnetic composites (SMC) stator tooth segments and a bonded rare-earth magnet ring. It was designed for high torque density and efficiency, and low cogging torque. Both 2D and 3D finite-element model results are provided and compared to the experimental measurements of the flux densities, back-EMF, cogging torque, inductance and power losses. Challenges were found in modelling the magnetization of the bonded-ring magnet. The rated efficiency and field-weakening performance are examined by using both measured and finite-element calculated parameters.