Comprehensive design and modeling of a super high-speed permanent magnet motor

This paper proposed a 3kW radial PMSM designed for operation up to 150,000 r/min. The design procedure of the machine is discussed, with modeling and simulation results. Thanks to the super high speed, the designed motor can achieve high energy density at 2.5 kW/kg(housing weight included) and efficiency is over 97%. The super high speed brings challenges on electrical, mechanical and thermal design. Proper design of the stator lamination, including bore diameter, outer diameter, slot, yoke thickness and airgap is explained. At high frequency, proximity effect and skin effect becomes significant, the effects have been analyzed and multi-strand Litz wires are chosen for this design. Double-layer distributed winding is used instead of concentric winding to reduce the harmonic EMF. The rotor structure is designed to endure the mechanical stress at high RPM. Thermal analysis is conducted, and a housing with water cooling is designed. The design is optimized in ANSYS Maxwell and simulation results verified the performance of the motor. A controller for the high speed drive has been developed for the motor.