| 摘要 |
PURPOSE:To reduce the power loss of filter sections and improve the efficiency of the whole power source system, by a method wherein a plurality of filter units are provided in parallel, and wherein load current is detected, and wherein operated filter units are changed in quantity to be used according to the detected value. CONSTITUTION:On a power converter for converting the DC of a DC power source 11 to AC by an inverter 12 and for feeding AC to a load 14 by shaping waveforms with filters, a plurality of the filter units 13-1-13-3 are connected in parallel with one another. The second unit and the following ones 13-2, 13-3 among the filter units are arranged respectively to be ON/OFF-controlled by switches S1-S4. Besides, a load current detector 15 is arranged to be connected to the electric circuit on the side of the load 14. According to the output of the detector 15, the operated unit quantity of the filters is controlled to be reduced when load current is diminished, and the operated unit quantity is controlled to be increased when the load current is increased. |
