This paper proposes a new circuit configuration for a buck-type active power filtering converter that has smaller and lighter reactors and suppresses DC output ripple voltage, and is also capable of suppressing input current harmonics without current detection or any special feedback control. This circuit configuration is suitable for use in rural telecommunications, where lightning resistance is considered especially important, and its application to rural telecommunications power supplies, such as those with rated outputs of 48 V 10 A, has enabled us to attain a number of excellent results. Circuit configuration, operation principle, simulation results, and experimental results on a practical model are described.