A photovoltaic power generating system and method for maximum power point tracking device

The invention discloses a maximum power point tracking method and a maximum power point tracking device for a photovoltaic power generation system in the technical field of solar photovoltaic power generation. The device comprises a maximum power point tracking (MPPT) controller, a temperature sensor, a voltage sensor, a current sensor, a power tube, a DC-DC converter, a diode, a first capacitor, a second capacitor, a first driving module, a second driving module and the like. The method comprises the following steps of: first acquiring the open circuit voltage and battery temperature of a photovoltaic cell, and obtaining a predicted voltage value corresponding to a maximum power point by utilizing a support vector machine prediction model; then regulating the duty ratio of pulse width modulation of the DC-DC converter by using a proportional integration controller to make actual working voltage rapidly reach the predicted voltage value corresponding to the maximum power point; and finally tracking the maximum power of the photovoltaic cell with a given perturbation step length by taking the predicted voltage value corresponding to the maximum power point as an initial value and adopting a perturbation and observation method. By the method and the device, the power generation efficiency of the photovoltaic power generation system can be effectively improved.