Performance of Halbach magnetised brushless ac motor

In this paper, an anisotropic bonded NdFeB Halbach magnetised ring magnet, which is oriented in powder alignment system during injection moulding and subsequently impulse magnetised, is employed. The features of such a Halbach magnetised machine, in terms of the airgap field distribution, and the back-emf and cogging torque waveforms, etc. have been compared with those which result with a Halbach magnet having discrete magnet segments have previously been compared.