The influence on the rotor loss of the high-speed motor by optimizing the rotor structure

Rotor Eddy current loss of high speed permanent magnet synchronous motor makes the motor efficiency drops, which can cause more serious problems, such as permanent magnet rotor demagnetization and affect the safe operation of the motor. The effect of segmenting permanent magnets on rotor loss was analysed with finite element analysis, Along with the axial segments increased, the eddy curent loss in the magnets can be reduced by segmenting,Loss in the permanent magnet is obviously reduced when permanent magnet is segmented around the circumference as the axial segment number exceeds a certain value. By using the shielding effect of the eddy-current magnetic field, Copper plating on inner and outer surface of rotor retain sleeve, although copper layer will produce eddy current losses, the magnetic field generated by the eddy currents counteract the harmonic components of the air gap magnetic field and reduce the permanent magnet rotor core, rotor protection loss set by analysing the thickness of the inner and outer coating distribution on the rotor eddy current loss, we obtained the optimal distribution of the copper layer.