High-speed axial-flux permanent-magnet generator with coreless stator

摘要

High-speed axial-flux generators (HSAFGs) with coreless stators are regarded as high-power-density, small-size, high-efficiency machines for use in distributed power generation systems (as microturbines). This paper presents a modelling procedure for such generators with details. The ratio of inner to outer diameter (λ) in axial-flux machines is considered in the same way that the ratio of length to diameter is considered in radial-flux (conventional) machines. The optimized λ is determined for an HSAFG with three rotors and two stators by careful consideration of the output voltage and efficiency variations versus λ. It is concluded that λ plays an important role in the HSAFG and requires careful attention when the machine is designed.