A Novel Approach to Extract Maximum Power from Partially Shaded PV Array

The modules of a PV array receive different intensity of solar irradiation under partial shading condition and hence mismatch losses occurs between the modules. Multiple local maxima exist in the power-voltage characteristics of a PV array and out of multiple local maxima one of them is a global maximum power point (GMPP). This paper presents a new approach to distribute the shading effect over the entire array to reduce the mismatch losses, and enhance the power output of a PV array. In this approach, the physical position of the modules in the Total Cross Tied (TCT) configuration are arranged, without changing the electrical connection of the modules, and also the arrangement of the modules in the TCT configuration is done in such a way that, the shading effect is distributed over the entire array, and hence it reduces the multiple local maxima in power-voltage characteristics of a PV array. Thus the tracking of GMPP in the present approach is simpler. In this paper, the output power of a PV array estimated theoretically and by MATLAB simulation for the TCT and the proposed configuration is compared. It is investigated that, the power generation of a PV array with proposed configuration is improved compared to the TCT configuration under different shading patterns.