| 摘要 |
PROBLEM TO BE SOLVED: To obtain a method for reducing residual ripples produced in a current when the current is supplied from a main power supply (commercial power supply) to a load through a rectifier, and an active filter. SOLUTION: A current path between a rectifier 2 and a load 10 is divided into a plurality of parallel current channels I1 , J1 or example, two circuits, and separate step-up converters are installed in these circuits. These converters are provided with switches 5a, 5b as part of a power factor controller. The switches are driven using switching signals out of phase from each other, and residual ripples in a main current input 9 are reduced by superposition of currents in individual current channels. The entire circuit has features similar to those of a power factor control circuit which operates at a relatively high switching frequency, but does not have its deficiencies, that is, deficiencies of switching loss and magnetization loss. |
