A Novel MPPT Control Algorithm Based on Peak Current

Aiming at the MPPT (maximum power point tracking) control of the fly-back type grid-connected microinverter, a novel maximum power point tracking control algorithm based on peak current sampling is studied, and a current sampling circuit composed of blocking diode and bias diode is proposed. Compared with maximum power point tracking methods of the conventional MPPT, the method in this paper does not need to calculate the actual power by multiplying the input voltage and the corresponding input current of the photovoltaic components. And the maximum power point of PV modules can be obtained according to comparing the detected sampling peak current of the switch tube. Therefore, the input voltage sampling circuit, the cost and the resources of the control chip are saved, and the complexity of the computation on maximum power point is simplified, thus ultimately achieving the MPPT fast control algorithm. The method in this paper has no need of sampling resistance or current Holzer, which improves the efficiency of grid-connected microinverter. The experimental results verify the correctness of the method studied in this paper.