Power supply device, power supply system, and method of controlling power supply

A power supply control system comprising:

• a power supply control device that includes a control unit, and a power path that is connected to a primary external power system, wherein the power path includes a first connection to provide power to a general load system and a separate second connection to provide power to an autonomous outlet;
• and
• a secondary external power generation system that is separate from the primary external power system and that is connected to the power supply control device, the secondary external power generation system including two or more photovoltaic cells and corresponding two or more second photovoltaic power conditioners connected to the photovoltaic cells,
• wherein when connection state information indicates that the primary external power system and the power path are in a disconnected state, the control unit is configured to control the power output of the two or more second photovoltaic power conditioners based on
• (a) an amount of power consumption of a specific load connected to the power supply control device through the autonomous outlet, and
• (b) a power generation output of the secondary external power generation system,
• wherein the autonomous outlet is configured to provide power when the connection state information indicates that the primary external power system and the power path are in a disconnected state,
• wherein two or more second photovoltaic power conditioners are configured to be controlled in synchronization with the primary external power system or an output of a power storage unit that is connected to the control unit,
• wherein the control unit is configured to increase the number of the second photovoltaic power conditioners to be turned on when it is estimated that inputtable power of a first power conditioner connected to the power storage unit will not be exceeded, and the control unit is configured to decrease the number of the second photovoltaic power conditioners to be turned on or to turn off all the second photovoltaic power conditioners when it is estimated that inputtable power of a first power conditioner connected to the power storage unit will be exceeded, and
• wherein, when it is determined that a minimum cell voltage of a storage battery is a discharge stop voltage or less, or power in the storage battery runs out, in a stand-by mode, a power supply state becomes a power supply stop state.

A method of controlling a power supply of a power supply device, the method comprising:

• controlling, when a connection state between a primary external power system and a power path, which includes a first connection to provide power to a general load system and a separate second connection to provide power to an autonomous outlet, is in a disconnected state, power output of two or more second power conditioners of two or more corresponding secondary external power generation units based on
• (a) an amount of power consumption of a specific load connected to the power supply control device through the autonomous outlet, and
• (b) a power generation output of the secondary external power generation unit,
• wherein the autonomous outlet is configured to provide power when the connection state between the primary external power system and the power path is in a disconnected state,
• wherein two or more second power conditioners are configured to be controlled in synchronization with the primary external power system or an output of a power storage unit that is connected to the control unit,
• wherein the control unit is configured to increase the number of the second power conditioners to be turned on when it is estimated that inputtable power of a first power conditioner connected to the power storage unit will not be exceeded, and the control unit is configured to decrease the number of the second power conditioners to be turned on or to turn off all the second power conditioners when it is estimated that inputtable power of a power conditioner connected to the power storage unit will be exceeded, and
• wherein, when it is determined that a minimum cell voltage of a storage battery is a discharge stop voltage or less, or power in the storage battery runs out, in a stand-by mode, a power supply state becomes a power supply stop state.