Novel Compact 3-D PM Machines for Ultra High Power Density Applications

Improving power density of electric machines is a growing interest due to the rapid development in electrification across transportation and aerospace sectors. This paper proposed a novel three-dimensional torque producing permanent magnet machine architecture in which the rotor consists of there rotor components interacting straight and the end winding portions of concentrated wound coils, significantly increasing the power density. The additional end axial rotor captures the extra torque through the interaction between the coil end winding and the rotor magnets, which would have been wasted in conventional cylindrical machines. The concept was developed and sized for a transportation application with a peak and rate operating points along its operating trajectory. The performance was verified using 3D finite element analysis. The results show that the torque gained from the extra end rotor is significant, making significant contribution on power density improvement.