Heat transfer investigations on a thermally superior alternative for the flux switching permanent magnet electric motor

Abstract

Severe temperature rise is not tolerated in the windings and permanent magnets (PMs) of the electric motors due to the resultant performance degradation, increased maintenance cost, and eventually the short-circuit faults. This article suggests a new approach to mitigating the temperature of components in a flux-switching PM (FSPM) motor using the concepts of heat transfer paths and heat flow diagrams. Accordingly, changing the location of the armature windings from the adjacency of the PMs to the middle tooth of the E-core stator blocks brings multiple thermal and electromagnetic merits to the proposed motor. In the heat generation stage, the numerical studies indicate that the total power losses of the motor decrease from 56.6 W to 39.6 W. Moreover, the maximum working temperature of the windings and PMs is cut by 36.4% and 40%, respectively, demonstrating the remarkable effect of the proposed strategy on temperature. From the electromagnetic point of view, the proposed motor outperforms the E-core FSPM motor due to the separation of the electrical and magnetic loading sources, resulting in the uniformity of the steel cores' flux density. Lastly, the thermal and electromagnetic experimental studies are provided to verify the outcomes of the analytical and numerical investigations.

Keywords

• Heat transfer
• Permanent magnet motors
• Heat flow diagram
• Heat generation
• Electromagnetic torque
• Thermal experiment