Comparative Study of Power Generation in Curved Photovoltaic Modules of Series- and Parallel-Connected Solar Cells

Curved photovoltaics (PVs) have gained attention for use in well-designed building and vehicle integration. To achieve higher output power, it is necessary to elucidate the characteristics of curved PV modules composed of many connected solar cells with current mismatching. In this study, we investigated the power generation in curved PV modules of solar cells connected in series and parallel to the curved surface. Nonplanar mini-modules with different curvatures were fabricated, and the PV module properties were extracted from the current-voltage measurements. The power generation in the curved modules decreased with respect to the reference flat module, which depended on the interconnections of the solar cells. Next, the PV properties were analyzed using a diode model, which could explain the higher power of the parallel interconnection compared with the series interconnection. Finally, we examined the selection of solar cell interconnections for practical applications. It was determined that the parallel interconnection can obtain higher power in an ideal model. However, it causes higher current for large-sized modules, which may cause additional resistivity losses in practical modules. Our findings indicate that solar cell interconnections should be considered when a practical curved PV module is designed.