Power control apparatus, power control system, and power control method

A power control system including a plurality of solar cell strings and a power control apparatus,

• wherein the power control apparatus includes:
• a plurality of transformers each configured to transform power generated by a corresponding one of a plurality of solar cell strings and outputting power transformed to an inverter, and
• a controller configured to control the plurality of transformers, wherein the plurality of transformers each include:
• a diode configured to prevent a reverse flow of power to be output from a corresponding one of the plurality of transformers, and
• a switch configured to open or close a connection between the solar cell string and the inverter, and
• wherein, when a diode of one of the plurality of transformers fails to prevent the reverse flow of the power to be output from the one of the plurality of transformers, the controller opens the switches of all of the plurality of transformers and then closes switches other than the switch of the one of the plurality of transformers.

A power control method of a power control apparatus having a plurality of transformers each configured to transform power generated by a corresponding one of a plurality of solar cell strings and outputting power transformed to an inverter,

• wherein the plurality of transformers each include a diode configured to prevent a reverse flow of power to be output from a corresponding one of the plurality of transformers, and a switch configured to open or close a connection between the solar cell string and the inverter, and
• wherein the power control method includes:
• a determination step of determining whether a diode of one of the plurality of transformers has failed to prevent a reverse flow of power to be output from the one of the plurality of transformers;
• an opening step of, when in the determination step the diode is determined as having failed to prevent the reverse flow of the power to be output from the one of the plurality of transformers, opening the switches of all of the plurality of transformers;
• and
• a closing step of closing switches other than the switch of the one of the plurality of transformers.