High Efficient and Cost-effective Solutions for Small Electric Motor Applications

To improve the performances of electric machines with concentrated windings for small motors, several solutions are presented in this paper. The flux barrier stator is an efficient technique that can improve the torque density by about 20%. If the installation space is very tight, a flat motor design with a double rotor can use all the available space for torque generation. Another solution for utilizing the installation space of the end windings is the hybrid stator with extended tooth tips in the axial direction. Based on these techniques, several examples of electrical machines are presented and analyzed by numerical methods and experimental tests.