| 摘要 |
PROBLEM TO BE SOLVED: To provide a back converter with improved efficiency through easy control. SOLUTION: In a back converter consisting of a DC power supply Vi, a switching element Q0, an inductor L0, and a diodeo D0, the voltage across the switching element Q0 is detected to control the switching element Q0, so that it is turned on in a timing, when the voltage across the element Q0 becomes minimum during the off-period of the switching element Q0. The converter is also provided with an auxiliary voltage source. The inductor current, having opposite polarity from that of the inductor current is caused to flow, when the switching element Q0 is turned on is allowed to flow in a closed loop including the auxiliary voltage source, the switching element Q0, and the inductor L0 when the switching element Q0 is turned off. The voltage value of the auxiliary voltage source is set nearly half that of the input voltage from the DC power supply. |
