Patent ID: 7719865
Filing Date: 2010-05-18
Classification: H02J,H02M,Y02E

Abstract:
1. A power conversion apparatus comprising: a plurality of single-phase inverters having respective inputs and outputs and converting input DC power from respective DC power sources to AC power, the outputs of the single-phase inverters being connected in series, wherein the outputs of the single phase inverters connected in series produce an output voltage with gradational output voltage control from a sum of output voltages produced by a combination of the single-phase inverters selected from the plurality of single-phase inverters, and the respective DC power sources that provide respective DC voltages input to respective single-phase inverters include a first DC power source producing the highest DC voltage of the DC voltages produced by the respective DC power sources, and at least one second DC power source; a booster circuit including a switch, wherein the highest DC output voltage, produced by the first DC power source, is generated from a third DC power source and supplied through the booster circuit, and, when the DC output voltage of the third DC power source exceeds a predetermined voltage, on-off operation of the switch in the booster circuit is stopped to stop boosting; and a DC-DC converter connecting the first DC power source to each of the at least one second DC power source.