Loss Calculation, Analysis, and Separation Method of 550 000 r/min Ultrahigh-Speed Permanent Magnet Motor

Loss characteristics and loss separation methods of ultrahigh-speed permanent magnet motors (UHSPMSM) are comprehensively studied in this article. In view of the influence of stator structure, material, winding type, control method, and fluid dynamics, the ac copper loss equivalent calculation model, fluid dynamic model, and finite element simulation model are established, respectively, to calculate and analyze the loss of each part of UHSPMSM. Moreover, a set of loss separation methods in dynamic is designed, which can separate stator core loss, dc copper loss, eddy copper loss, rotor eddy current loss, and mechanical friction loss of UHSPMSM one by one under the condition of considering the high-frequency electromagnetic field and fluid dynamic. A 550 000 r/min prototype and back-to-back loss separation setup is built to complete the experiment. Finally, loss distribution of the motor is obtained, which provides a certain reference for the loss research of an ultrahigh speed motor.