Power convertor, power generation system, and power generation control method

A power generation system, comprising:

• a plurality of power generation modules connected in series, each of which generates direct-current power;
• and
• at least one power convertor corresponding to at least one of the power generation modules, wherein each power convertor comprises:
• a buck-boost circuit to be applied with an input voltage to convert the input voltage into an output voltage for output, the input voltage being generated by the at least one of the power generation modules, the buck-boost circuit including a switch;
• a switching controller that executes maximum power-point tracking by switching on and off the switch repeatedly to control power conversion of the buck-boost circuit such that the at least one of the power generation modules generates maximum direct-current power;
• and
• a mode controller, wherein the mode controller is configured to:
• cause the switching controller to execute the maximum power-point tracking when an input current from the at least one of the power generation module is larger than a preset current threshold;
• and
• when the input current is equal to or less than the current threshold, cause the switching controller to stop the maximum power-point tracking by stopping switching on and off the switch repeatedly to cause the buck-boost circuit to output the input voltage as the output voltage without the power conversion,
• wherein in each power converter, the mode controller causes the switching controller to stop the maximum power-point tracking by stopping switching on and off the switch repeatedly to cause the buck-boost circuit to output the input voltage as the output voltage without the power conversion, in response to the input current decreasing to be equal to or less than the current threshold after exceeding the current threshold.

A power generation control method for controlling a power generation system comprising a plurality of power generation modules connected in series, each of the power generation modules generating direct-current power, at least one of the power generation modules being subjected to power conversion of a power convertor, the power convertor comprising a buck-boost circuit to be applied with an input voltage to convert the input voltage into an output voltage for output, the input voltage being generated by the at least one of the power generation modules, the buck-boost circuit including a switch;

• and a switching controller that executes maximum power-point tracking by switching on and off the switch repeatedly to control power conversion of the buck-boost circuit such that the at least one of the power generation modules generates maximum direct-current power, the method comprising:
• causing the switching controller to execute the maximum power-point tracking when an input current from the at least one of the power generation modules is larger than a preset current threshold;
• when the input current is equal to or less than the current threshold, causing the switching controller to stop the maximum power-point tracking by stopping switching on and off the switch repeatedly to cause the buck-boost circuit to output the input voltage as the output voltage without the power conversion;
• and
• in response to the input current decreasing to be equal to or less than the current threshold after exceeding the current threshold, causing the switching controller to stop the maximum power-point tracking by stopping switching on and off the switch repeatedly to cause the buck-boost circuit to output the input voltage as the output voltage without the power conversion.