Comparative Study of Small Electrical Machines With Soft Magnetic Composite Cores.

In this paper, various kinds of electrical machines with soft magnetic composite (SMC) cores are compared, based on the qualitative and quantitative comparison methods. In the first part, the performances of five typical electrical machines with SMC cores are qualitatively compared. Simplified power equations for transverse flux, axial flux, and radial flux electrical machines are deduced to show the main difference among them and key design points of each machine. In the second part, the outer rotor claw pole machine (CPM) and outer rotor transverse flux machine (TFM) are comprehensively compared in a quantitative way, based on the three-dimensional finite-element method. It shows that the power capability of the outer rotor CPM is much higher than that of the TFM. On the other hand, the outer rotor CPM has higher cogging torque and no-load losses than the TFM. Furthermore, the four outer rotor radial flux machines are optimized and compared with the outer rotor CPM. The calculated results of the outer rotor TFM are compared with the experiment results, showing that the analysis results match well with the experiment ones. Several useful and interesting conclusions have been obtained for the electrical machines with SMC cores. [ABSTRACT FROM AUTHOR]