DC SWITCHING DEVICE, DC SYSTEM INCLUDING THE SAME, POWER STORAGE DEVICE, AND POWER CONVERSION DEVICE

摘要

PROBLEM TO BE SOLVED: To stably supply a voltage to a DC bus in a DC system that a power storage device comprised of a plurality of series-connected storage batteries is directly connected to the DC bus.SOLUTION: A power storage device 3 includes a plurality of storage batteries B1 and B2 series-connected between a positive bus-bar PL and a negative bus-bar SL of a DC bus 1. A DC switching device 5 is disposed between the DC bus 1 and the power storage device 3. The DC switching device 3 includes: a determination section 50 for selecting at least one from the plurality of storage batteries B1 and B2 according to a residual capacity of each of the plurality of storage batteries B1 and B2; and switches SW1 and SW2 for connecting the at least one storage battery selected by the determination section 50 to the DC bus 1.