| 摘要 |
PROBLEM TO BE SOLVED: To provide an isolated DC-DC converter having high efficiency of power conversion even when a DC power supply is a low voltage-large current DC power, and also having high efficiency of power conversion even when a load is light. SOLUTION: In the DC-DC converter, switching loss of a switching element Q is reduced by current resonance and voltage resonance of a full-bridge composite resonant circuit 5 in a converter 3 and the efficiency of power conversion of the converter 3 is improved by a combination of voltage step-up by a voltage step-up transformer 6 and voltage duplication by a voltage duplication circuit 7. Combined with these effects, the efficiency of power conversion of the entire converter 3 is improved and the full-bridge composite resonant circuit 5 shifts to burst oscillation when a load is light, the switching loss of the switching element Q can be reduced, and thus high efficiency of power conversion can be achieved when the load is light. COPYRIGHT: (C)2011,JPO&INPIT |
