| 摘要 |
PROBLEM TO BE SOLVED: To detect an erroneous pole position signal, if any, by judging the rationality of a pole position signal corresponding to the pole position of a permanent magnet synchronous motor and an incremental signal corresponding to the rotational angle thereof thereby making a decision whether these two signals are correct or not. SOLUTION: An elevator comprises a pole encoder 8 delivering a pole position signal Pp depending on the pole position of a permanent magnet synchronous motor 1, and an AB phase encoder 9 delivering an incremental signal Ep corresponding to the rotational angle thereof. A control block 10 calculates a phase data θs by taking the pole position signal Pp into a phase calculating block 11 and corrects the phase data θs by taking in the incremental signal Ep. In this regard, phase shift θe of the phase data θs is outputted to a phase abnoramality decision block 18 where a decision is made that the phase is abnormal if the phase shift θe exceeds a specified value and the elevator is stopped and the abnormality is notified. According to the arrangement, safety of elevator system can be enhanced. |
