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In this paper, we investigate the power degradation in a novel photovoltaic (PV) cell reconfiguration named KenDoKu (KDK) topology under different shading patterns. We analyze how a modification in the linkage between the PV cells within a shaded PV module can affect its effectiveness. The proposed approach relocates the physical position of the PV cells within the PV module without any change in electrical connections and redistributes the shading effects over the PV module for the improvement of the power generation. To achieve this purpose, modeling and simulation are performed for a set of various shading patterns such as homogeneous, sectional, and scattered shadings. The simulation model used is a combination of two-diode model and Bishop’s model. This model is applied to a PV module and is implemented in LTSpice software to quantify the impact of shading on P-V characteristics. The performance of the KDK topology is compared to other optimized configurations such as total-cross-tied (TCT), bridge link-total cross tied (BL-TCT), honey comb-bridge link (HC-BL), series parallel-total cross tied (SP-TCT) and existing odd-even (OE) and Latin square (LS) schemes of interconnection. The effectiveness of the KDK approach is evaluated in terms of the characteristics of P-V curves, global maximum power (GMP), mismatch power loss MPL (%), fill factor FF (%), and performance ratio PR (%). The simulated results revealed that the KDK configuration scheme performs better in terms of generating maximum power under the considered partial shading conditions. The proposed approach reduces the maximum power losses (MPL) and improves the fill factor (FF) with respect to OE and LS configurations in the most of the cases. Moreover, experimental verification is also carried out. The obtained results show that the KDK configuration outperforms the other analyzed PV cell rearrangement in terms of increased power.

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In this paper, we investigate and analyze parameters degradation in a typical photovoltaic (PV) cell, which lead to power loss under dark as well as light condition using measured current-voltage (I-V) data. A nonlinear least squares method to extract the parameters such as the reverse saturation currents, the ideality factors, the series and shunt resistances of the cell from the dark current-voltage (I-V) curves is used. In order to analysis the sensitivity of the dark current-voltage (I-V) measurement to each of the six extracted parameters as a function of the voltage as well as the temperature and the density current, we simulate the operation of a silicon solar cell (KXB0022-12X1F). The analysis of the dark current-voltage (I-V) curves permit us to detect variation as small as 15% in the series resistance. We also extends the use of dark as well as light current-voltage (I-V) measurements to modules configurations of cells and uses a nonlinear least squares method to evaluate the cell efficiency parameters in the modules. Results obtained show a degradation of the values of the maximum power (Pmax) as compared to initial values by about 12, 3%, 12, 06% and 10, 21 % respectively in Total-Cross-Tied (TCT), Bridge-Link (BL) and Honey-Comb (HC) configurations.