| 摘要 |
<p>An injection molding machine of which a moving part is driven by an AC servomotor (4). The d-phase current in the direction of magnetic flux established by the field system and the q-phase current orthogonal thereto are found from the drive current of the AC servomotor (4) and the rotor phase through d-q conversion. The current is controlled by the DC method while setting the d-phase current at zero and using the q-phase current as a current command. In the DC current control, the phase of the q-phase current command which is an effective component of the current command is advanced when magnetic saturation occurs, thereby to suppress the effect of magnetic saturation and to decrease a decrease of the torque.</p> |
