| 摘要 |
<p>PURPOSE: To suppress the low-frequency axis torsional vibration of an AC-to-DC converter by controlling the control angle which controls the DC power of a DC system in the phase of the voltage at an AC-DC connecting point. CONSTITUTION: The low-frequency axis torsional vibration suppressing circuit 1 of an AC-to-DC converter is constituted of a detector 4 which detects the voltage phase displacement at an AC-DC connecting point and a device which generates correcting signal for controlling phase. The detector 4 detects the displacement 6 of a voltage phase from the voltage amount 2 at the connecting point of an AC system with a DC system and the device 5 outputs anα- correcting signal 3 for controlling phase expressed inΔα, found from a prescribed transfer function based on the displacement 6. In an area where a phase lag is generated due to the time constant of the transfer function, phase compensation of the magnitude which is decided by a gain is performed. Therefore, the divergence of low-frequency axis torsional vibrations can be prevented.</p> |
