To provide a motor controller which can execute determination about the demagnetization of a motor where the possibility of wrong determination is reduced.
The motor controller includes a resolver 32 which detects the rotational speed of a rotor, and a control unit 30 which controls the rotation of the motor. The control unit 30 determines whether the operation state of the motor belongs to a determination execution range or belongs to a determination inhibition range, based on the detected rotational speed MRN1 of the rotor and a torque command TR1, and in case that the operation range belongs to the determination execution range, it executes demagnetization determination for determining whether the demagnetizing factor of the permanent magnet of the motor has dropped under a specified value, based on the motor voltage. The control unit 30 inhibits the determination of demagnetization in case that the operation state of the motor belongs to the determination inhibition range.
HAYASHI KAZUHITO
KUTSUNA MASAKI
Toshio Morita
Yutaka Horii
Nobuo Arakawa