INVERTER CONTROL METHOD AND INVERTER CONTROL DEVICE

A control method of inverter for driving motor including a magnet, comprises detecting a rotation state of the motor by a rotation sensor, detecting current of the motor by a current sensor, calculating, based on a torque command value, a detection value of the rotation state detected by the rotation sensor, and detection current detected by the current sensor, a voltage command value for controlling a voltage of the motor by a controller for controlling the inverter, specifying a value of at least one of a local maximum value, a local minimum value, and an average value of the torque voltage command value included in the voltage command value as a torque determination target command value by the controller, comparing a demagnetizing determination threshold value with the torque determination target command value by the controller, and determining whether or not demagnetization of the magnet occurs in accordance with the compared result.