| 摘要 |
PURPOSE: To obtain a harmonic suppressor for a distribution system in which even a severe harmonic can be suppressed stably without causing overloading. CONSTITUTION: One winding of a matching transformer 5 and an LC filter 7 are connected in series with a distribution system and the other winding of the matching transformer 5 is connected with a stationary power converter 6 to constitute a voltage absorbing active filter 4. The active filters 4 are distributed for the distribution line thus constituting a harmonic suppressor. A system for detecting the voltage of the distribution system and controlling the stationary power converter to have a sine wave voltage is provided with a sine wave command and the current of the active filter 4 is detected and controlled by a comparison circuit receiving the controlled voltage and a current limit set value. A multiplier multiplies the controlled voltage output by an output from the comparison circuit and a current command is held at a predetermined level on condition that the controlled voltage output exceeded a predetermined current limit value. Harmonics of the distribution system are absorbed while suppressing the filter current below the predetermined level. |
