A power supply device comprising: an input unit to which AC power is input from an AC power supply ; a first rectifying unit configured to convert the AC power passed through the input unit into DC power; a power-factor improving unit configured to improve a power factor of the DC power output from the first rectifying unit ; a first power storage unit configured to store the DC power passed through the power-factor improving unit and configured to supply the stored DC power to a load side; characterised in that the power supply device further comprises: a second rectifying unit connected to a portion where the input unit is connected to the AC power supply , the second rectifying unit being configured to convert the AC power into the DC power; a second power storage unit configured to store the DC power passed through the second rectifying unit , the second power storage unit being connected to the power-factor improving unit in parallel to the first power storage unit ; and a control unit configured to operate using the electric power stored in the second power storage unit and, when a short-circuit failure occurs in the power-factor improving unit , being configured to perform control for interrupting the input unit to interrupt a route that starts at the input unit , runs, from the input unit , via the second rectifying unit , the second power storage unit , the power-factor improving unit , and the first rectifying unit , and ends at the input unit . an input unit to which AC power is input from an AC power supply ; a first rectifying unit configured to convert the AC power passed through the input unit into DC power; a power-factor improving unit configured to improve a power factor of the DC power output from the first rectifying unit ; a first power storage unit configured to store the DC power passed through the power-factor improving unit and configured to supply the stored DC power to a load side; characterised in that the power supply device further comprises: a second rectifying unit connected to a portion where the input unit is connected to the AC power supply , the second rectifying unit being configured to convert the AC power into the DC power; a second power storage unit configured to store the DC power passed through the second rectifying unit , the second power storage unit being connected to the power-factor improving unit in parallel to the first power storage unit ; and a control unit configured to operate using the electric power stored in the second power storage unit and, when a short-circuit failure occurs in the power-factor improving unit , being configured to perform control for interrupting the input unit to interrupt a route that starts at the input unit , runs, from the input unit , via the second rectifying unit , the second power storage unit , the power-factor improving unit , and the first rectifying unit , and ends at the input unit . a second rectifying unit connected to a portion where the input unit is connected to the AC power supply , the second rectifying unit being configured to convert the AC power into the DC power; a second power storage unit configured to store the DC power passed through the second rectifying unit , the second power storage unit being connected to the power-factor improving unit in parallel to the first power storage unit ; and a control unit configured to operate using the electric power stored in the second power storage unit and, when a short-circuit failure occurs in the power-factor improving unit , being configured to perform control for interrupting the input unit to interrupt a route that starts at the input unit , runs, from the input unit , via the second rectifying unit , the second power storage unit , the power-factor improving unit , and the first rectifying unit , and ends at the input unit . <EOS>