In this paper

the uniform analysis of the electromagnetic performance of the permanent magnet synchronous motor with eccentricity fault is realized based on the airgap field modulation theory

and the theory is enriched and developed. The air gap variation resulting from the eccentricity fault is abstracted as the “modulator”

and the “eccentricity modulation operator” is defined to reflect the influence of eccentric fault on the air gap of the motor. On this basis

the modulating effect of eccentricity fault on air gap magnetic field is studied

and the influence of eccentricity fault on back electromotive force

electromagnetic torque

radial electromagnetic wave

unbalanced magnetic pull

and inductance of permanent magnet synchronous motor is analyzed. The finite element simulation and experiment results show that the harmonics generated by eccentricity fault have almost no effect on the back electromotive force

but can produce torque pulsation

which has a serious impact on the radial electromagnetic force wave and the unbalanced magnetic pull of the motor. The change of air gap will also cause the inductance change.