To improve power using efficiency at the time of using plural solar battery assembly, and to realize stable power converting operation.
Photovoltaic cell strings 35, 36, and 37 are respectively provided with boosting chopper circuits 39a, 39b, and 39c a to constitute a DC power source circuit 22, and chopper control circuits 61a, 61b, and 61c respectively make switching controls of the boosting chopper circuits 39a, 39b, and 39c, so that the photovoltaic cell strings 35, 36, and 37 can be controlled for the maximum power point tracking. An inverter control circuit 60 calculates a reference power Po*, by adding a full output power Po of the cell strings 35, 36, and 37 and a power correction value ΔPo, based on an output voltage VCH, and adjusts an output power. A control power source circuit 28 operates the cell string, whose output voltage is the highest among the cell strings 35-37 as an input.
HATANO YUKIHIKO
YONEMOTO TAKESHI
