| 摘要 |
<p>Provided is a direct-current power supply system in which an electric storage device for backup can be effectively used while the reliability of backup in case of a power outage is maintained high. Specifically provided is a direct-current power supply system provided with a first power storage device (16) which is always connected in parallel to a first direct-current load (14) and has a power storage capacity capable of supplying a minimum amount of direct-current power for backup to the first direct-current load (14) when the voltage of alternating-current power (11) instantaneously drops or the supply thereof is instantaneously stopped, a second power storage device (17) which can be connected in parallel to the first power storage device (16) and the first direct-current load (14) and has a larger power storage capacity than the first power storage device (16), a first switch (SW1) which is provided in a circuit that connects a power conversion device (13) and the second power storage device (17), a second switch (SW2) which is provided in a circuit that connects the second power storage device (17) and a second direct-current load (50), a power outage detection means (21) which detects the stop of supply of the alternating-current power (11) to the power conversion device (13), and a circuit switching means (20) which, when the direct-current power stored in the second power storage device (17) is supplied to the second direct-current load (50), turns off the first switch (SW1) and turns on the second switch (SW2), and, when the stop of supply of the alternating-current power (11) to the power conversion device (13) is detected by the power outage detection means (21), preferentially turns on the first switch (SW1) and turn off the second switch (SW2).</p> |
