PURPOSE: A power delivery system and a method thereof have a load function by inputting the output of a power conversion device to an electrical device and reduce surplus energy by regenerating power. CONSTITUTION: A first power conversion device (102) connects a power source (101) and an electrical device (103). The electrical device is driven by power supplied from the first power conversion device. A second power conversion device (104) connects the electrical device and the first power conversion device. A control device (105) controls the operation of the first power conversion device and the second power conversion device. The electrical device outputs power to the second power conversion device. The first power conversion device converts the inputted power and outputs the power to the electrical device or the power source. [Reference numerals] (100) Power transfer system; (101) Power source; (102) First power conversion device; (103) Electrical device; (104) Second power conversion device; (105) Control device
