| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a power-conversion device whose cost can be cut by decreasing the number of component parts of a preliminary charging circuit or by miniaturizing the circuit. <P>SOLUTION: A high-frequency power supply 4 is used as a power supply for the pre-charging circuit for pre-charging DC smoothing capacitors of a converter 3. This structure enables a current-limited element to be omitted, that has conventionally been provided between a preliminary charging switch 5 and a pre-charging step-up transformer 7. Also, even when it is provided, its current rated value can be made small and the step-up transformer 7 can be miniaturized. <P>COPYRIGHT: (C)2004,JPO |
