Grid-connected power conditioner and distributed power supply network

摘要

PROBLEM TO BE SOLVED: To reduce increase of a conversion loss caused by (DC/AC) or (AC/DC) conversion.SOLUTION: A system interconnection power conditioner comprises: a first voltage conversion part by which a voltage of DC power supplied from a DC power supply device is converted into a DC voltage and outputted to a DC bus; a second voltage conversion part which is connected between a power storage device and the DC bus and by which DC power received from the DC bus is converted and supplied to the power storage device in a charge operation state of the power storage device, and DC power received from the power storage device is converted and outputted to the DC bus in a discharge operation state of the power storage device; a bidirectional inverter for system interconnection that is operable while switching an AC/DC conversion operation in which AC power in an AC bus connected to a system power source is converted into DC power and outputted to the DC bus and a DC/AC conversion operation in which DC power in the DC bus is converted into AC power and outputted to the AC bus; and control means for controlling operations of the first voltage conversion part, the second voltage conversion part and the bidirectional inverter for system interconnection.SELECTED DRAWING: Figure 1