| 摘要 |
The present invention is a device for detecting a rotation position that can detect a rotation position with high accuracy even when an offset has occurred. A motor (2) has: a field (22) which includes a permanent magnet, and an armature (21) which includes coils (21u, 21v, and 21w) of three or more phases. The field (22) and the armature (21) rotate relatively. A detector (431) detects whether or not a first line induced voltage (Vun) and a second line induced voltage (Vvn) match each other, the first line induced voltage (Vun) being a potential difference of a first phase potential of phase potentials relative to a reference potential, and the second line induced voltage (Vvn) being a potential difference of a second phase potential of the phase potentials other than the first phase potential relative to the reference potential. The phase potentials is outputted by the armature due to an induced electromotive force. The reference potential is any one of a minimum phase and a maximum phase. A rotation-position setting unit (432) sets, to a predetermined value, an estimation value of a rotation position of the motor 2 at a point in time when the first line induced voltage (Vun) and the second line induced voltage (Vvn) match each other. |
