Global Hybrid Maximum Power Point Tracking for PV Modules Based on a Double-Diode Model

Abstract

Photovoltaic systems under partial shading conditions (PSC) need to operate at the global maximum power point (GMPP) to extract the maximum possible power. Partial shading is characterized by the exhibition of a multi-peaked behavior in the voltage power (P-V) curve. Hence, there are several methods capable of extracting the GMPP from a multi-peaked P-V curve with various distinct characteristics. However, it is important that these techniques have fast dynamic responses to reduce power losses during the GMPP searching process. To fill this very important research gap by improving performance, an efficient hybrid global maximum power point tracking (GMPPT) technique combining a fast double-diode model-based technique and the classic Perturb and Observe (P&O) is proposed. The double-diode model used was modeled for a large number of series and parallel connected modules in a shaded photovoltaic array, which can be used as a valuable tool in the practical evaluation of a photovoltaic installation under PSC. The proposed method accurately tracks the global maximum power point at any operation point with good tracking speed and excellent efficiency. In addition, simulation and experimental results are presented to demonstrate its performance and comparative results with two other GMPPT techniques.