Power control system for energy storage devices, and control device and control method thereof

A power control system for a plurality of energy storage devices, the power control system comprising:

• a first converter configured to perform a voltage conversion, the first converter having one end connected to any one of a first power system and a renewable energy source and another end connected to a direct current (DC) linker;
• a second converter configured to perform a voltage conversion, the second converter having one end connected to a second power system and another end connected to the DC linker;
• a first energy storage device configured to store electric energy;
• a direct current-to-direct current (DC-DC) converter configured to perform a voltage conversion, the DC-DC converter having one end connected to the first energy storage device and another end connected to the DC linker;
• a second energy storage device connected to the DC linker and configured to store electric energy;
• and
• a control device configured to control a voltage of the first converter and a voltage of the second converter based on a voltage of the second energy storage device,
• wherein the control device comprises a reference marker configured to calculate reference power of the second energy storage device based on power of the first converter and power of the second converter and adjust a voltage of the DC linker based on the calculated reference power.

A control method of a power control system for a plurality of energy storage devices including a first converter configured to perform a voltage conversion, the first converter having one end connected to any one of a first power system and a renewable energy source and another end connected to a direct current (DC) linker;

• a second converter configured to perform a voltage conversion, the second converter having one end connected to a second power system and another end connected to the DC linker;
• a first energy storage device configured to store electric energy;
• a direct current-to-direct current (DC-DC) converter configured to perform a voltage conversion, the DC-DC converter having one end connected to the first energy storage device and another end connected to the DC linker;
• and a second energy storage device connected to the DC linker and configured to store electric energy, the control method comprising:
• setting a reference voltage of the second energy storage device;
• setting a voltage of the other end of the second converter based on the set reference voltage of the second energy storage device;
• setting a voltage of the other end of the first converter based on the set voltage of the other end of the second converter;
• calculating, by a control device of the power control system, reference power of the second energy storage device based on power of the first converter and power of the second converter;
• and
• adjusting, by the control device, a voltage of the DC linker based on the calculated reference power.