A New Photovoltaic Arrays Fixed Reconfiguration Method for Reducing Effects of One- and Two-Sided Mutual Shading

Abstract

Low distance between photovoltaic (PV) arrays can lead to the mutual shading between them. This can lead to significant power losses. Usually, these shadows can be seen in PV plants with limited land such as buildings' roof. In this paper, a PV arrays fixed reconfiguration method is presented in order to reduce the effects of one- and two-sided mutual shadings in total cross tied (TCT) arrangements. Two-sided mutual shading appears when the array is shaded in two separate areas, while there is only one shaded part in the array in one-sided mutual shading. In this method, the physical locations of the modules are rearranged without changing the electrical interconnections. To reduce the effects of these shadings, first, their important features are explained. Then, the optimal array rearrangement is determined by considering all possible mutual shadows (MSHs). In mutual shading conditions, the obtained arrangement is capable of equally dispersing shaded modules in different array rows, while there is no need to add any additional switches or sensors. Due to this equal dispersion, there is no need to use the bypass diodes for maximum power extraction in this condition. The simulation results validate the effectiveness of this method.