Design of an axial-flux electric machines with amorphous alloy for flywheel energy storage system

This paper presents an axial flux permanent-magnet (AFPM) machine used in flywheel energy storage system (FESS). Amorphous alloy is used in the stator, which can reduce coreloss remarkablely when the FESS is working in high-frequency. A new multi air-gap AFPM machine with multi-rotor and multi-stator is proposed, and the different numbers of motors can make up different power of the FESS. A 3-D finite element method was used to analyses the design and performances of AFPM, the result shows that the AFPM machine with amorphous alloy have lower iron loss than that with silicon lamination, with can improve the efficiency of FESS effectively.