| 摘要 |
PURPOSE:To enable the run of a synchronous motor at a power-factor of 1 and reduce the pulsation in the torque of the motor, by connecting a naturally commutated power converter and a forcedly commutated power converter to each other to provide a combined power converter for driving the synchronous motor. CONSTITUTION:A synchronous motor 7 is energized through a power transformer 1, a power rectifier 2, DC reactors 3, 4, a naturally commutated power converter 5 and a forcedly commutated power converter 6. The power converter 5 is commutated by a signal from a position detector or the like mounted correspondingly to the position of the rotor of the synchronous motor 7. The commutation of the power converter 6 is delayed by the double of an effective commutation lead angle beta in comparison with that of the power converter 5. As a result, the input currents to both the power converters 5, 6 can be almost equalized to each other to set the fundamental power-factor of the motor at 1. |
