A significant challenge in the progress and development of Building-Integrated-Photovoltaic (B-I-PV) systems is concerned with the extraction of maximum power from PV modules. The PV system architecture is an essential feature to extract the maximum power. The conventional PV-central-inverter architecture consists of various connections among the PV modules, which are sensitive to shading effects and produces mismatching power loss under partial shading conditions (PSCs). Hence, photovoltaic-distributed-maximum power point tracking (PV-D-MPPT) architecture has been proposed to extract the maximum power. In PV-D-MPPT architecture, the output terminals of DC-DC converters are connected either in series or parallel configuration. The main limitation of the series configuration in open-loop MPPT control is the cross-coupling effect. Because of cross-coupling effects, the maximum-power-point (M-P-P) operation of shaded PV modules is lost under PSCs. The lost in M-P-P operation of shaded PV module also affects the unshaded modules M-P-P operation. Under cross-coupling effects, the DC-DC converters are consuming the power instead of delivering to the load. Despite the research activity, there are hardly any papers presenting a clear, comprehensive and mathematical analysis on the existence of cross-couplings in PV string-integrated-converters (S-I-Cs). This article presents a mathematical analysis and also explains the conditions for the existent of cross-coupling effects. The experimental results also validate with the mathematically analysed results. This article also discusses the modeling of the two-diode model of PV module, design of boost type S-I-C, and the Perturb and Observe (P&O) MPPT algorithm implementation.

Maximum power extraction from the photovoltaic (PV) system plays a critical role in increasing efficiency during partial shading conditions (PSCs). It directly reduces the output power of the PV array. There are different factors, such as bypass diode configuration, array size, array configuration, shade intensity, environmental conditions etc., affecting the performance of the solar photovoltaic panel. Furthermore, series (S), parallel (P), series-parallel (SP), total-cross-tied (TCT), bridge-linked (BL), and honey-comb (HC), etc., are the various configurations to deal with the mentioned issues. But these PV array configurations also have drawbacks, such as low dispersion factor, mismatch losses, and line losses under partial shading conditions. To overcome these issues, the reconfiguration of the PV array is one of the effective approaches. A comprehensive study of literature shows that PV modules are connected under different reconfigured schemes namely Sudoku, Optimal Sudoku, Magic square, zig-zag, Skyscraper, etc. In this paper, a comprehensive review is performed to highlight the advantages and limitations of each scheme. This study can be used to address the advancement in this area since some parameter comparisons are made at the end of every technique, which might be a prominent base-rule for picking the most promising reconfiguration technique for further research.

Currently, the critical challenge in solar photovoltaic (PV) systems is to make them energy efficient. One of the key factors that can reduce the PV system power output is partial shading conditions (PSCs). The reduction in power output not only depends on a shaded region but also depends on the pattern of shading and physical position of shaded modules in the array. Due to PSCs, mismatch losses are induced between the shaded modules which can cause several peaks in the output power-voltage (P-V) characteristics. The series-parallel (SP), total-cross-tied (TCT), bridge-link (BL), honey-comb (HC), and triple-tied (TT) configurations are considered as conventional configurations, which are severely affected by PSCs and generate more mismatch power losses along with a greater number of local peaks. To reduce the effect of PSCs, hybrid PV array configurations, such as series-parallel: total-cross-tied (SP-TCT), bridge-link: total-cross-tied (BL-TCT), honey-comb: total-cross-tied (HC-TCT) and bridge-link: honey-comb (BL-HC) are proposed. This paper briefly discusses the modeling, simulation and performance evaluation of hybrid and conventional 7 $\times$7 PV array configurations during different PSCs in a Matlab/Simulink environment. The performance of hybrid and conventional PV configurations are evaluated and compared in terms of global maximum power (GMP), voltage and currents at GMP, open and short circuit voltage and currents, mismatch power loss (MPL), fill factor, efficiency, and a number of local maximum power peaks (LMPPs).

The grid-connected or standalone PV central inverter architecture is comprised of several PV modules which are connected in different ways to form the PV array. The power generation capability of the PV array is primarily affected by partial shading conditions (PSC). Due to PSCs, the power output of the PV array is dramatically reduced, and mismatching losses are induced in the PV modules. Based on the extent of these problems, multiple peaks also appear in the power-voltage (P-V) curve, which makes it very difficult to track the global maximum power point (GMPP). The main objective of this research paper is to model and simulate the series (S), series-parallel (SP), bridge-link (BL), honey-comb (HC), total-cross-tied (TCT) and proposed triple-tied (TT) solar PV array configurations under various partial shading scenarios. The performance of all PV configurations is evaluated under a uniform approach, considering eight different shading scenarios. The performance of the considered PV configurations is analyzed in terms of their mismatching power losses, fill factors, efficiency, global maximum power points (GMPPs), local maximum power points (LMPPs), voltages and currents at GMPPs, open circuit voltage and short circuit currents. The above-mentioned PV configurations are modeled and simulated in a Matlab/Simulink environment by considering the KC-200GT module parameters.