Field modulated permanent magnet motor operates based on multiple airgap magnetic field harmonics

which possess the merit of high torque density. However

under inverter supply

the harmonic components of the airgap magnetic field asynchronous to rotor speed become more abundant

leading to an increase in rotor loss. The rotor loss composition of a field modulated permanent magnet motor under the dual modulation behavior of voltage source inverter space vector pulse width modulation and motor airgap field modulation is studied

and the effect of rotor magnetic barrier structure on harmonic loss is analyzed. First

based on the airgap field modulation theory

the speed and frequency of airgap magnetic density space harmonics supplied by sinusoidal current and inverter are calculated. Second

the current waveform of high-frequency harmonics is obtained through the inverter drive control circuit

and the equivalent current sheet loss calculation model is used to analyze and calculate the rotor loss of the motor supplied by the inverter. Then

through the introduction of a magnetic barrier rotor structure

the rotor loss caused by space and time harmonics is effectively suppressed without affecting the torque. Finally

experiments verify the accuracy of the theoretical analysis and simulation.