| 摘要 |
PROBLEM TO BE SOLVED: To precisely detect the pole position of a permanent magnet motor. SOLUTION: An electric signal is outputted in response to leakage flux from a magnet rotor 17 by a magnetic sensing element 27. A computing means 2 detects a change in the output of the magnetic sensing element 27 as a basic reference position of a rotor pole, corrects the basic reference position by Δθcorresponding to the magnitude of stator currents IU, IV, IW and current phases at the time of computing a pole reference position θ and the rotational angle of a rotor, and computes rotational angles, θre, θre', thereby correcting the effect of the stator current and the phase upon the magnetic sensing element while using the inexpensive magnetic sensing element 2. It is thus possible to precisely detect the rotational angle of the magnet rotor. |
