Design optimization of photovoltaic arrays on curved surfaces

Flexible photovoltaic (PV) arrays often have to be mounted on surfaces that have a significant amount of curvature. These include solar-powered vehicles, planes, and also some wearable devices. However, this inevitably leads to non-uniform solar irradiance among connected PV cells. If one cell among series-connected PV cells receives significantly lower solar irradiance, the overall power generation of the string is reduced. While previous works dealt with this by employing sophisticated run-time techniques, we show that design-time approaches that determine the electrical series-parallel connection of a PV array could also significantly enhance the power output. In this paper, we propose a k-means clustering-based algorithm to group PV cells/modules with similar solar irradiance to form a PV string, even allowing irregular arrays, to maximize the power generation of the array for a given irradiance profile. Our experimental results show that the power generation of a PV array could be increased by 84% compared to usual PV array organizations that do not take the curvature of the mounted surface into account.