Distribution board and battery pack

1. A distribution board comprising:

a power line for supplying, to a plurality of loads, including a normal load and an emergency load, AC power that is supplied from a power system;

a plurality of pack housings which house a plurality of battery packs, respectively, each pack housing including a connecting unit, and each battery pack including a connecting terminal unit for charge and discharge, the connecting units being connectable to and disconnectable from the connecting terminal units of the battery packs;

an AC/DC converter which converts the AC power supplied from the power system into DC power, and supplies the DC power to the battery packs housed in the pack housings to charge the battery packs;

a DC/AC inverter which converts, into AC power, the DC power discharged from the battery packs via the connecting units, and supplies the AC power to the loads; and

a switching controller which switches between a grid connection mode and a self-sustained operation mode, the grid connection mode being a mode in which the AC power supplied from the power system is supplied to at least the normal load, the self-sustained operation mode being a mode in which electric power discharged from the battery pack is supplied to at least the emergency load via the DC/AC inverter;

wherein, when at least one of the battery packs is removed while electric power is supplied from the battery packs to the emergency load, the switching controller continuously supplies electric power to the emergency load by using the battery packs excluding the at least one battery pack that has been removed.

2. The distribution board according to claim 1 ,

wherein at least one of the battery packs includes a display which displays a remaining power level of the battery pack, and

the at least one pack housing that respectively houses the at least one battery pack that includes the display is oriented in an orientation that allows the display of the battery pack connected to the connecting unit to be viewed.

3. The distribution board according to claim 1 , further comprising a detector which detects whether or not electric power is being supplied from the power system, wherein the switching controller selects the grid connection mode when the detector detects that electric power is being supplied from the power system to the distribution board, and

selects the self-sustained operation mode when the detector detects that no electric power is being supplied from the power system to the distribution board.

4. The distribution board according to claim 1 , further comprising a switch for selecting the grid connection mode or the self-sustained operation mode, wherein the switching controller switches between the grid connection mode and the self-sustained operation mode according to the mode selected by the mode switch.

5. The distribution board according to claim 1 , further comprising a receiver which externally receives a control signal, wherein the switching controller switches between the grid connection mode and the self-sustained operation mode according to the control signal received by the signal receiver.

6. The distribution board according to claim 5 ,

wherein the control signal received by the receiver indicates which one of the grid connection mode and the self-sustained operation mode is to be selected, and

the switching controller switches between the grid connection mode and the self-sustained operation mode according to the mode indicated by the control signal.

7. The distribution board according to claim 5 ,

wherein the control signal received by the receiver is a power saving request signal, and

the switching controller switches from the grid connection mode to the self-sustained operation mode when the receiver receives the power saving request signal.

8. The distribution board according to claim 1 , further comprising a charge controller which controls charge of the battery packs, wherein the charge controller obtains information about a remaining power level of the battery packs by communicating with the battery packs, and when the remaining power level is below a predetermined threshold value in the grid connection mode, the charge controller charges the battery pack that has remaining power level below the predetermined threshold value by supplying, to the battery pack being charged, the electric power supplied from the power system, and when the remaining power level is above or equal to the predetermined threshold value, the charge controller stops supplying, to the battery pack being charged, the electric power supplied from the power system.

9. The distribution board according to claim 1 ,

wherein at least one of the battery packs includes a universal serial bus (USB) port, and

the electric power charged in the at least one battery pack including the USB port is supplied to a device different from the distribution board via the USB port in a state where the at least one battery pack including the USB port is removed from the connecting unit.

10. The distribution board according to claim 1 ,

wherein at least one of the battery packs is removably connected to a device different from the distribution board via the connecting terminal unit, and

the electric power discharged from the battery pack that is connected to the device different from the distribution board is supplied to the device via the connecting terminal unit.