A Global Maximum Power Point Tracking Algorithm for Photovoltaic Systems Under Partially Shaded Conditions Using Modified Maximum Power Trapezium Method

In this paper, a modified maximum power trapezium (M-MPT) method for global maximum power point tracking (GMPPT) of photovoltaic (PV) systems under partially shaded conditions (PSCs) is proposed. Compared with the traditional maximum power trapezium (MPT) method, the proposed method introduces a variable current range lower bound by utilizing monotonic output characteristics of the PV array. Moreover, considering the influence of the initial operating point of the PV array on the scanning path under dynamic PSCs, a judgement mechanism for the initial voltage is added in the modified method. The proposed method guarantees that the global maximum power point is tracked accurately with a smaller voltage scanning range and shorter tracking time under all conditions. Furthermore, the excellent performance of the proposed method has been verified by both simulation and experimental results.