| 摘要 |
PROBLEM TO BE SOLVED: To prevent the position of a magnetic pole of a rotor from being detected erroneously, by providing an abnormality judgment means by which whether an abnormality is generated or not in a conversion means is judged on the basis of an index signal, which is generated due to a conversion by using the conversion means and on the basis of a signal for abnormality judgment. SOLUTION: While a north marker NM is at a high level, whether a signal SG2 for abnormality judgment falls to a low level from the high level is judged, and whether an abnormality is generated or not in an R/D converter is judged. Then, when the signal SG2 for abnormality judgment becomes high, a motor controller performs an abnormality detecting and processing operation so as to be changed over to a sensorless drive mode, and it drives a motor without detecting the position of the magnetic pole of a rotor. In this manner, since it is possible to judge whether the abnormality is generated or not in the R/D converter on the basis of the north marker NM and on the basis of the signal SG2 for abnormality judgment. As a result, it is possible to prevent the position of the magnetic pole of the rotor from being detected erroneously. |
