Patent ID: 9236764
Filing Date: 2016-01-12
CPC Classification: H01M,H02J,Y02E

Claim Text:
1. A DC power supply system comprising: a DC power supply; a secondary battery for backing up the DC power supply; and a backup power supply circuit connected in parallel to the DC power supply, the backup power supply circuit including the secondary battery, wherein the backup power supply circuit includes: a first charging DC/DC converter configured to charge the secondary battery when a voltage of the DC power supply is higher than a voltage of the secondary battery; a first discharging DC/DC converter configured to discharge an electric power charged in the secondary battery when a voltage of the DC power supply is higher than a voltage of the secondary battery; a second charging DC/DC converter configured to add an extra voltage to a voltage of the DC power supply by using an electric power of the secondary battery to charge the secondary battery when the voltage of the DC power supply is lower than a voltage of the secondary battery; a second discharging DC/DC converter configured to discharge an electric power charged in the secondary battery when a voltage of the DC power supply is lower than a voltage of the secondary battery; and a control circuit configured to control the first charging DC/DC converter, the first discharging DC/DC converter, the second charging DC/DC converter and the second discharging DC/DC converter.