A DC power supply apparatus used with a power storage element comprises a rectifier circuit that converts AC current from an alternating current generator into a DC current; an input current adjusting circuit that receives DC current from the rectifier circuit to adjust current flow from the rectifier circuit to the power storage element; an output current adjusting circuit that receives current from the power storage element and adjusts current flow from the power storage element to an output node; and a control circuit that operates at least one of the input current adjusting circuit and the output current adjusting circuit based on a predetermined condition of the power storage element.