Stator tooth and rotor pole shaping for low pole flux switching permanent magnet machines to reduce even order harmonics in flux linkage

High-speed machines require structurally robust rotor to withstand high centrifugal forces. Flux switching permanent magnet (FSPM) machines are ideal for high speeds since they have a simple and robust rotor structure. They also utilize permanent magnet (PM) in the stator enabling them to achieve high power density. It is desirable to keep the operating frequency minimized to reduce core losses and cost of power electronics. A 6-stator slot, 4-rotor pole (6/4) FSPM machine has the lowest operating frequency for a three phase FSPM configuration but suffers from heavy harmonic distortion in flux linkage. This paper aims to identify structural modifications that can minimize the dominant 2
^nd
order harmonic component to make the 6/4 configuration amiable for high-speed applications. The analysis and methods proposed in this paper will be useful in tackling harmonic content of FSPM machines in general.