Power Conversion Device and Method for Controlling Power Conversion Device

A power conversion device comprising:

• a first power supply;
• a second power supply;
• three first power conversion cells each converting input power and outputting the converted power and having input terminals connected in parallel with respect to the first power supply;
• and
• three second power conversion cells each converting input power and outputting the converted power and having input terminals connected in parallel with respect to the second power supply,
• wherein the power output from one of the first power conversion cells and the power output from one of the second power conversion cells are combined to output a first phase power;
• the power output from another of the first power conversion cells and the power output from another of the second power conversion cells are combined to output a second phase power;
• the power output from the other of the first power conversion cells and the power output from the other of the second power conversion cells are combined to output a third phase power;
• and
• the first phase, second phase, and third phase powers are output as phase powers or line powers of a three-phase system.

A method for controlling a power conversion device including three first power conversion cells each converting input power and outputting the converted power and having input terminals connected in parallel with respect to a first power supply and three second power conversion cells each converting input power and outputting the converted power and having input terminals connected in parallel with respect to a second power supply, the method comprising:

• outputting a first phase power by combining the power output from one of the first power conversion cells and the power output from one of the second power conversion cells;
• outputting a second phase power by combining the power output from another of the first power conversion cells and the power output from another of the second power conversion cells;
• outputting a third phase power by combining the power output from the other of the first power conversion cells and the power output from the other of the second power conversion cells;
• and
• outputting the first phase, second phase, and third phase powers as phase powers or line powers of a three-phase system.