PURPOSE: To provide a higher harmonic wave compensator which remarkably reduces current ripple of parallel multiplexed inverters and whose capacity can be made large and whose size can be reduced and which can be highly efficient.

CONSTITUTION: Between an a.c. supply system and a.c. terminals of N sets of polyphase inverters 410, 420 and 430, the plurality of combined reactors 461U1-461W3 are located, each of which has the plurality of primary coils and the plurality of secondary coils which correspond to the a.c. terminals of each inverter. One terminal of the secondary coil is connected to the a.c. terminal of the polyphase inverter 410, 420 and 430 and the other terminal is commonly connected to the same phases of each polyphase inverter. The primary coil connects the same phases of each polyphase inverter 410, 420, 430 in series and one terminal of the primary coil which is serially connected to the common connection of the secondary coils is connected to the same phases of the inverters 410, 420 and 430 and the other terminal of the serially connected primary coils of the combined reactors is connected to the a.c. supply system.