Inverter control method and inverter

In the present invention, zero-phase modulation using a two-phase modulation method or a three-phase modulation method is applied to correct a three-phase voltage command, and a selector selects the two-phase modulation method or three-phase modulation method. During mode switching in the two-phase modulation method, the three-phase modulation method is inserted in an amount corresponding to half a period of a triangular wave carrier signal. Further, when there is a switch from the N mode to the P mode of the two-phase modulation method at a trough of the triangular wave carrier signal or a switch from the P mode to the N mode at a crest of the triangular wave carrier signal, after the current mode of the triangular wave carrier signal is continued for half a period, the three-phase modulation method is inserted in an amount corresponding to half a period of the triangular wave carrier signal. As a result, in this inverter control method, the occurrence of current ripples during two-phase modulation mode switching is suppressed.