| 摘要 |
PROBLEM TO BE SOLVED: To provide a system linkage inverter capable of suppressing increase in the waveform distortion of an output current even when an output power to a system is low. SOLUTION: The system linkage inverter inputs a DC power from a DC power source 1 and outputs an AC power to the system 9. In this case, an intermediate stage capacitor 3 connected to the output of a booster converter 2 to remove high frequency components has a plurality of capacitors. A relay 10 is connected to at least one of the capacitor. When the effective value of an output current i0 to the system is a predetermined output current effective value threshold value or less, a control circuit 8 turns OFF the relay 10 to reduce the capacity of the capacitor 3. Thus, the reactive current to the capacitor 3 is reduced, and even at the low output power time, the output current waveform of the sine wave having a small distortion can be maintained. The system has a means for switching the capacity of the capacitor 3 to a small value corresponding to a system voltage VAC, an intermediate stage capacitor current iM. |
