Performance of coreless-winding axial-flux permanent-magnet generator with power output at 400 Hz-3000 rev/min

An axial-flux permanent magnet machine (AFPM) topology with a coreless winding is proposed for generator units required aboard ships, aircraft or hybrid-electric vehicles. In the proposed AFPM configuration, the winding consists of rhomboidal shaped coils encapsulated in fibre-reinforced epoxy resin. The coils have a double-layer arrangement to leave space for a cooling water duct being used to remove heat directly from the interior surface of the winding. The overall machine structure has high compactness and lightness, and because of the lack of the iron core generator operation with power output at 400 Hz can be accomplished with high efficiency and acceptable voltage regulation. The paper discusses the basic design and construction of AFPM generators with coreless winding and experimental results taken from a 16 poles machine prototype rated 70 kW, 3000 rev/min are finally reported.