Device for stabilizing direct current (dc) distribution system

A device for stabilizing a direct current (DC) distribution system, wherein the system includes a power supply stage, the device comprising:

• a capacitor unit including a first capacitor and a second capacitor, wherein the first and second capacitors are coupled in series to each other, and wherein the capacitor unit is coupled in parallel with the power supply stage such that the first and second capacitors are charged by a DC voltage supplied from the power supply stage;
• an inverter unit including two pairs of driving switching elements and a pair of common switching elements, wherein the inverter unit is configured to convert the voltage charged in the capacitor unit into an AC power and to provide the AC power to a motor connected to the device;
• a voltage stabilization unit including the pair of common switching elements, wherein the voltage stabilization unit is configured to control the common switching elements based on a charging or discharging signal to charge the capacitor unit with the DC voltage supplied from the power supply stage or to discharge the voltage charged in the capacitor unit to the power supply stage;
• a switching unit including a plurality of switches, wherein the plurality of switches of the switching unit is configured to selectively enable the inverter unit or the voltage stabilization unit;
• and
• a control unit configured to compare the DC voltage supplied from the power supply stage with a reference range, and to provide the charging or discharging signal to the voltage stabilization unit based on the comparison result.