Patent ID: 7371963

Claim:
A photovoltaic power generation system comprising: a first solar cell string composed of a plurality of solar cell elements or solar cell element groups connected in series; a second solar cell string composed of a plurality of solar cell elements or solar cell element groups connected in series, the second solar cell string being connected to the first solar cell string in parallel; electric power converting means for converting DC electric power outputted from these solar cell strings, to AC electric power and controlling so that a maximum output electric power is inputted; boosting means disposed between the second solar cell string and the electric power converting means, for carrying out boosting DC voltage outputted from the second solar cell string so that a maximum output electric power is inputted and so that the output voltage of the second solar cell string is equal to the output voltage of the first solar cell string and controlling the regulated output voltage so as not to be higher than the output voltage from the first solar cell string; and voltage regulating means disposed between the second solar cell string and the electric power converting means, for regulating a DC voltage outputted from the second solar cell string, and regulating an output voltage of the second solar cell string to be close to an output voltage of the first solar cell string, wherein, the voltage regulating means has a controlling section for controlling an operation so as to stop regulation of the DC voltage of the DC electric power supplied from the second solar cell string when the second solar cell string begins electric power generation earlier than the first solar cell string, and the electric power converting means is actuated by the first solar cell string.