| 摘要 |
<P>PROBLEM TO BE SOLVED: To detect the occurrence of abnormality in the counter value of a position sensor which counts the pulse signals from the position sensor, without providing a new sensor, etc. <P>SOLUTION: Each time the edge of the pulse signal from each electric angle sensor of a brushless motor appears, the difference (Pi-1-Pi) between the counter value Pi-1 of the position counter P at the last appearance of the edge and the counter value Pi of the position counter P at this edge appearance is computed. The difference (Pi-1-Pi) reflects the slippage, when the counter value of the position counter P has slipped from the value corresponding to the actual rotating angle of the brushless motor. That is, the above difference (Pi-1-Pi) slips from its normal value J by the amount of the slippage. Accordingly, it can detect the abnormality occurrence in the counter value of the position counter P, based on that the difference (Pi-1-Pi) is not a normal value J. <P>COPYRIGHT: (C)2007,JPO&INPIT |
