| 摘要 |
PROBLEM TO BE SOLVED: To provide a system interconnection inverter that achieves stable switching operation in a small-current region near a zero cross of a system voltage and has small loss.SOLUTION: The system interconnection inverter has a bridge circuit, a filter circuit, and control means for controlling the bridge circuit, and supplies power obtained from a DC power supply to a commercial system through in order of the bridge circuit and filter circuit. The bridge circuit is composed of a plurality of switches. The control means has a mode 1 that controls the switches so as to prevent distortion of a current flowing through the commercial system and a mode 2 that controls switches so as to reduce loss of the switches, and includes operating mode switching means for switching between the mode 1 and the mode 2 and ripple detection means for detecting an amplitude of a ripple of an output current of the bridge circuit. The control means sets, to the mode 1, the period where the amplitude of the ripple of the output current of the bridge circuit is larger than an average output current amplitude of the bridge circuit. |
