A Study of Partially-Shaded PV Modules with Overlapping Diodes

A Configuration of bypass diodes affects the performance of photovoltaic (PV) system when it is exposed to partial shading. The power-voltage (P-V) curve of shaded string has multiple power peaks (MPPs) one of them is a global maximum power (GMPP) due to the exploitation of bypass diodes. There are two configurations of bypass diodes: non-overlapped and overlapped. Almost all PV studies are based on the non-overlapped bypass diodes, the effects of the diodes are well understood. On the other hand, a complete analysis for the effects of the overlapped bypass diodes on the performance of the PV module has not been yet systematically disclosed. In this paper, mathematical equations describe the dynamic performance of the PV module with overlapping diodes under partial shading conditions are developed. The electrical characteristics of the PV module with different bypass diodes configurations are comprehensively studied under different partial shading conditions by using MATLAB Simulink.