| 摘要 |
PURPOSE:To enable detecting a motor malfunction in its early stages by providing a malfunction detection circuit for detecting the abnormality of a rotational position signal. CONSTITUTION:A decoder 5 decodes a rotational position signal from a position sensor 4 and gives a decoded signal to a gate circuit 20. Said gate circuit 20 controls a transistor bridge 22 according to said decoded signal and PWM control signal. Also, an f-V conversion circuit 25 outputs a speed feedback signal Nf from said rotational position signal. A power application control circuit 2 outputs said PWM control signal according to the deviation of a current command signal from a current feedback signal if corresponding to the deviation of a speed command signal from said speed feedback signal. On the other hand, when the rotational position signal is continuously on an H or L level, a malfunction detection circuit 8 judges that an abnormality has occurred in an apparatus, and indicates said abnormality. |
