| 摘要 |
PURPOSE:To smoothly operate a synchronous motor by operating a forcible commutation type frequency converter in parallel with a load commutation type frequency converter in intermittent operation range, thereby reducing the torque ripple generated in the motor. CONSTITUTION:An inverter 27 communicates by a forcible communicating circuit or forcibly commutates by an inverter using a self-extinguishing type power converter such as a large power transistor. A frequency converter 100 for commutating a load is mainly operated always in an operating range exceeding an intermittent starting range to control a synchronous motor 15 at variable speed. A frequency converter 200 for forcibly commutating with the intermittent starting range as a center is operated. Thus, the torque of the motor 15 during the intermittent start can be reduced or the increase in the generated torque ripple can be suppressed. |
