Performance Evaluation of Axial-Flux Machine with Water-Cooling and Fractional-Slot Distributed-Winding

The reduction of space harmonic in winding magnetic motive force (MMF) is important for axial-flux permanent magnet synchronous machine (AFPMSM). For the 12-slot/10-pole winding and 24-slot/10-pole winding, comparative analysis of winding MMF is finished with winding function method(WFM). Analysis results show that fractional-slot distributed-winding (FSDW) have much lower total harmonic distortion (THD) than that of fractional-slot concentrated-winding (FSCW). It is beneficial to reduce eddy-current loss in PMs. An AFPMSM prototype with a 24-slot/10-pole combination is manufactured and tested at no-load condition. No-load back-EMF wave is measured at 1000rpm and 3000rpm. Theory and experiment prove that AFPMSM with FSDW layout has a better balance between THD of winding MMF and THD of no-load back-EMF.