Thermal Comparison of Axial and Radial Flux Permanent Magnet Motor with the Same Volume

Thermal property is a key issue for the parameter determination and machine type selection. In this paper, the equivalent thermal network models (ETNMs) for temperature rise calculation of axial flux permanent magnet motor (AFPM) and radial flux permanent magnet motor (RFPM) are analyzed and built up respectively at first. And then, the temperature rise change regulation of winding and permanent magnet of AFPM and RFPM with the same volume were analyzed and compared considering the different machine parameters which are the number of conductors per slot, polar arc coefficient, permanent magnet thickness, air gap length and slot size et.al. Finally, a prototype of AFPM is trial-manufactured and tested. Comparison between the calculated date and the tested data of temperature rise verifies the correctness of the proposed ETNMs.