Coupled theoretical modelling for the photoelectric performance by the concave-bent flexible PV module

Flexible PV module can fit with complex building skins and provide electricity for the building users. However, for the concave bent PV module, the special structure will cast shadow on itself, resulting in power loss during the working conditions, which is rarely investigated in previous studies. Combined optical-electrical-thermal model is decoupled to describe the realistic physical field and predict the concave module's electrical power output and working temperature. The beam shading ratio (BSR) and the diffuse shading ratio (DSR) are proposed based on the microfacet subdivision, which describes the real-time solar irradiance distribution and quantify the influence of self-shadow on the photoelectric performance by the concave-bent module under dynamic real-time working conditions. The concave PV module with the longitudinal/lateral layout is constructed and outdoor experiments are conducted to collect the data for the theoretical model verification. The parametric analysis is carried out to investigate the influence of inclination, curvature, and azimuth, demonstrating that increasing inclination and curvature angles raise power loss due to shading. Weather data of four cities are imported into the model to conduct annual performance simulation with longitudinal/lateral installation respectively. The model established in this paper has significant value for performance prediction in complex surface photovoltaic systems.