Analytical Modeling and Experimental Validation of Rotor Harmonic Eddy-Current Loss in High-Speed Surface-Mounted Permanent Magnet Motors

The temperature rise of the rotor caused by harmonic eddy-current loss constrains the performances of high-speed permanent magnet (PM) motors. Excessive temperature rise can even result in irreversible demagnetization in the PM. An analytical model for the rotor harmonic eddy-current loss of high-speed surface-mounted PM motors in consideration of eddy-current reaction fields, harmonic currents, stator slotting, and different rotation states of the rotor is proposed, which can be utilized to reliably calculate and evaluate the rotor harmonic eddy-current loss. The accuracy and effectiveness of this analytical model are validated by using the finite-element method and a proposed experimental method.