An Electrothermal Model of Partially-Shaded Building-Integrated Photovoltaic Systems

This article presents an electrothermal model of modular photovoltaic (PV) panels with protective bypass diodes (BD) capable of receiving unique irradiance inputs to accurately represent partial shading (PS) of building–integrated PV (BIPV) systems. The electrical modeling of the electrothermal model uses an eleven-parameter functional form (11PFF) of the single diode model (SDM) and incorporates an electrical representation of the BDs. The thermal modeling of the electrothermal model determines PV panel and BD junction box temperatures from measurable environmental variables, which directly influence the model's electrical behavior. A parameter identification method for the electrothermal model, based on experimental current–voltage curves, is developed. The electrothermal model is calibrated and validated with experimental data from Valparaíso, Chile, achieving an out-of-sample mean absolute percentage error of 6.26% in power prediction. The calibrated electrothermal model is built in an electromagnetic transient program to benchmark its computational efficiency against a competitive model. The calibrated electrothermal model is also implemented in a Python–SketchUp framework to estimate BIPV energy production based on dynamic computer–aided design (CAD)–based BIPV system shading and environmental condition data. A case study in Perugia, Italy, shows that the simulation framework, which integrates the validated electrothermal model with CAD–based PS analysis and environmental condition data, yields more realistic energy estimates than a similar framework using a competitive electrothermal model, with deviations of up to 13.21%, and no significant increase in computational burden.