POWER CONVERSION SYSTEM

PROBLEM TO BE SOLVED: To provide a power conversion system in which an inverter is connected to a commercial power supply system, for initial charging of a smoothing capacitor with an AC power.SOLUTION: The power conversion system includes smoothing capacitors 21-23 for smoothing output voltages of single-phase inverters 17-20 which are subjected to gradation control, first switches 31-33 connected between the single-phase inverters 17-20 and an AC power source 30, and serial connection bodies 40-42 which comprise current limiting resistors 34-36 and second switches 37-39 both connected in parallel to the switches 31-33 respectively. The initial charging is performed from the AC power source 30 to the smoothing capacitors 21-23 by way of the serial connection bodies 40-42.