| 摘要 |
PURPOSE:To employ a motor in such application as full rotation of the motor upon throw-in of power supply causes a trouble by detecting the position of a pole when the motor is started to be rotated by gradually increasing its torque in a state that the motor is steady. CONSTITUTION:Since the torque of a motor 5 is gradually increased when the command value of a peak current command Im is slightly increased at each time a current electric angle thetae becomes 2pi, it soon overcomes a frictional torque to rotate in a positive or negative direction according to the relationship between the initial position of the pole and the angles thetae, thetae' at that time. In this case, an incremental encoder 6 attached to the motor 5 is simultaneously rotated to output pulse signals PA, PB. Accordingly, it is compared with a set value of preset small amount obtained by counting the number of pulses to detect a small rotation of the position of the pole together with its direction. It can be employed in such application as the rotation of the motor 5 upon turn ON of power source cause a trouble. |
