A Permanent Magnet Synchronous Machine with Interior Halbach Arrays

Regular permanent magnet (PM) synchronous machines with Halbach arrays are mostly surface-mounted, which are only suitable for low-speed applications. In this paper, a PM synchronous machine with interior Halbach arrays is proposed for both low-speed and high-speed operations. The stator core and winding are the same with regular PM machines, while the key difference is the rotor PM structure, i.e. one PM pole is composed of two embedded PMs and a sandwiched spoke PM. The unique rotor configuration offers higher torque density, efficiency, overload and flux weakening capabilities than regular PM machines. Besides, in order to further reduce the torque ripple of the proposed PM machine with interior Halbach arrays, the rotor notching is introduced.