| 摘要 |
<p>In the disclosed power conversion device, an inverter circuit (100) is connected to an AC power supply (1) in series, and a smoothing capacitor (3) is connected to the latter stage thereof via a converter circuit (300) comprising semiconductor switch elements (101a to 104a). A control circuit (10) controls the converter circuit (300) by creating a shunt period (T) in each cycle, during which the smoothing capacitor (3) is bypassed. Furthermore, the control circuit (10) controls the inverter circuit (100) so as to improve the power factor of the AC power supply (1), using a current command that brings the voltage across the smoothing capacitor (3) to a target voltage. If the voltage of a DC voltage source (105) for the inverter circuit (100) exceeds a prescribed maximum, the control circuit (10) controls the inverter circuit (100) by increasing the current command, increasing the amount of discharge from the DC voltage source (105). This makes it possible to stably continue control even if the voltage from the DC voltage source (105) for the inverter circuit (100) fluctuates widely.</p> |
