Maximum power point tracking device for a solar electric generation system and a tracking method for the same

A maximum-power-point tracking device for a solar electric-generation system that includes a solar battery and a DC/DC converter, the maximum-power-point tracking device comprising:

• a sampling module configured to detect an output current and an output voltage of the solar battery;
• a controlling module configured to:
• determine a target current value according to an initial target current value and a preset current difference value;
• determine a value of an input current and a value of an output current of a proportional-integral adjustment according to the output current of the solar battery and the target current value;
• determine a duty cycle according to the output current of the proportional-integral adjustment;
• and
• output a controlling signal for controlling the output current of the solar battery according to the duty cycle;
• and
• a driving module configured to:
• receive the controlling signal from the controlling module;
• and
• output a driving signal to adjust the output current of the solar battery to the target current value according to the controlling signal.