| 摘要 |
The purpose of the present invention is to enable direct conversion of three-phase AC power to high-precision high-frequency single phase AC power. A configuration for achieving the foregoing comprises: a bidirectional switching circuit 10 that switches the supply of input three-phase AC power to a load LD on or off; and a control unit 20 that conducts virtual AC/DC conversion for determining a plurality of line-voltage generation zones for selecting two phases of the input three-phase AC power at a prescribed switching cycle and in accordance with a plurality of modes classified in accordance with the magnitude relationship of the voltage of each phase in the input three-phase AC power, and that generates a switching pattern for the bidirectional switching circuit 10 in order to conduct virtual DC/AC conversion in accordance with the plurality of line-voltage generation zones, on the basis of a second carrier waveform pattern CW2, which corresponds to the plurality of modes, and a U-phase control signal RWa and a V-phase control signal RWb, which correspond to the output-side phase. The prescribed switching cycle is one fraction of an integer of a half-cycle of a single-phase AC signal that generates the single-phase AC power. |
