Motor detection method and device and magnetic suspension motor

The embodiment of the invention discloses a motor detection method and device and a magnetic suspension motor. The detection method comprises the steps of obtaining an amplitude voltage value of a motor rotor of a to-be-detected motor in a preset time period; calculating the motion displacement of the motor rotor based on the amplitude voltage value; and judging the relationship between the motion displacement of the motor rotor at the next moment and the motion displacement of the motor rotor at the previous moment in the preset time period, and determining the rotation direction of the motor rotor according to the judgment result. According to the invention, the rotation direction of the motor rotor is determined by detecting the relationship between the motion displacements at the moment of forward and backward motion of the motor rotor, so that the technical problems of high production cost and low popularity rate of reverse rotation detection caused by the need of adopting additional sensors, hardware ci