Analytical modeling of surface-inset machines having harmonics injected into Halbach magnet shape with salient iron

A surface-inset machine model having harmonics injected into Halbach magnet shape with salient iron and an analytical modeling method have been proposed. For the proposed model, considering the magnet outer surface shape with sinusoidal and third harmonic injection, after the analytically derived magnetic fields by solving the constructed matrix equations, the optimal third harmonic amplitude to fundamental amplitude ratio and the optimal magnetization angle have been determined from the field functions. The electromagnetic performances have been predicted and compared with other two surface-inset models. The comparison results show that the proposed optimized model has the largest electromagnetic torque with the same magnet consumption. Finally, the finite element analysis predictions have been provided for verification the analytical performances.