PURPOSE: A microgrid system is provided to rapidly recover the voltage to commercial voltage by supplying power to a subordinate using a second energy storage device. CONSTITUTION: A first energy storage device(10) operates in a current control mode. A second energy storage device(20) operates in an output control mode. The second energy storage device is connected between the first energy storage device and a load(30). The current control mode controls current of the front end track. The output control mode outputs the power corresponding to the change of voltage and frequency.
