| 摘要 |
PURPOSE:To suppress the jump of an armature voltage due to the speed rise of a motor at the load removing time within a rated voltage range by controlling the speed command to the deceleration side immediately when the load is removed. CONSTITUTION:A changeover switch 19 selects a setter 10 to control to acceleration or constant speed, and a speed pattern generator 11 outputs a speed pattern having a constant speed range coincident to the set value of the setter 10. A speed control system controls the armature current due to the comparison with the speed detection signal with this speed pattern as a speed command. A field control system controls the field current from the strengthening field so far to a weakening field when the armature voltage of the motor becomes the voltage exceeding the bottom speed. Then, a changeover switch 19 is switched to a setter 18 side by the detection immediately before the load is removed, and the output of the generator 11 is lowered at the prescribed alope to the voltage corresponding to the speed lower than the base speed set to the setter 18. |
