Improving the Power Output of a Partially Shaded Photovoltaic Array Through a Hybrid Magic Square Configuration With Differential Evolution-Based Adaptive P&O MPPT Method

Abstract

A partially shaded photovoltaic (PV) array's characteristic curve is convoluted due to the disparity in irradiance levels between shaded and unshaded PV panels, resulting in power mismatch losses. This work presents a new hybrid approach combining the magic square (MS) array configuration and differential evolution-based adaptive perturb and observe (DEAPO) maximum power point tracking (MPPT) methodology to overcome the aforementioned problem. The proposed hybrid methodology is implemented in two steps: first, repositioning the PV panels as per the MS configuration to decrease the power losses of partial shading. In MS configuration, the concentrated shadow on a single row or column can spread over to the entire PV array equally without any physical or electrical switching of PV panels. Second, the DEAPO MPPT method is developed to find the global peak power point on the PV characteristic curve. Proportional-integral-derivative controller coefficients are optimized by differential evolution (DE) to enhance the tracking speed and convergence of the adaptive P&O MPPT. The simulation study of this work has been implemented using 4 × 4, 6 × 6, and 9 × 9 PV arrays in matlab/simulink environment, and the real-time validation is done through a 4 × 4, 5 kW PV array. The proficiency of the proposed hybrid approach is tested by creating various nonuniform and uniform shading patterns on the PV array. The simulation and experimental results prove that the proposed hybrid approach increases the power output by 19% and 20% higher than the existing total-cross-tie (TCT) configuration under nonuniform and uniform shading cases, respectively.