A comparison of power density for axial flux machines based on general purpose sizing equations

Based on the concept of the converter fed machine (CFM), an optimal machine design can be considered as the best match of the machine topology, the po wer electronic converter and the performance specification. To compare powe r production potential of axial flux machines with various topologies, diff erent waveforms of back emf and current, general purpose sizing and power d ensity equations for such machines are needed. In this paper, a general app roach is presented to develop and to interpret these equations. Sample appl ications of the sizing and power density equations are utilized to compare the axial flux toroidal permanent magnet (AFTPM) machine and the axial flux two-stator permanent magnet (AF2SPM) machine.