| 摘要 |
Provided is a power conversion device that improves efficiency by reducing loss in semiconductor elements and prevents increases in the size and cost of a device. In the present invention, a power conversion device is provided with a closed circuit that comprises a switching element 3, a fast recovery diode 4, and a capacitor 5, and a reactor 2, with the switching element 3, the diode 4, and the reactor 2 constituting a chopper circuit so that an input voltage is converted to a prescribed voltage by the operation of the switching element 3 and that a current from the reactor 2 flows through the switching element 3 or the diode 4 in accordance with whether the switching element 3 is ON or OFF, wherein: a series circuit comprising a rectifier diode 21 with high reverse recovery loss and low forward voltage drop and a switching element 22 with low withstand voltage and low forward voltage drop is connected in parallel with the diode 4; and the switching element 22 is turned ON when the switching element 3 is OFF, and the switching element 22 is turned OFF before the switching element 3 transitions to an ON state. |
