Coupled electrical-thermal performance estimation of photovoltaic devices: A transient multiphysics framework with robust parameter extraction and 3-D thermal analysis

Realistic performance estimations of photovoltaic (PV) require a clear understanding of coupled electrical-thermal effects. Herein, a novel multiphysics framework, consisting of an electrical sub-model with improved parameter extraction and a thermal sub-model with 3-D thermal analysis, is proposed and validated to achieve reliable, fast, and all-sided performance estimations of PV. The electrical sub-model is firstly validated against experimental data and shows high robustness, with relative errors within 0.075% and elapsed time within 0.045 s. Then, the framework is validated against the experimental data on five consecutive summer days. Regardless of weather conditions or PV technologies, the simulated power output, back-surface temperature, and current-voltage curves are highly consistent with the measurement data. Notably, non-linear temperature-efficiency dependence and non-uniform temperature fields are observed in the results, with a maximum temperature difference of 4 degrees C and a peak temperature of about 54 degrees C. These results firmly indicate the necessity of coupled simulation and 3-D simulation. Finally, cross-comparisons with other methods are conducted. The electrical sub-model performs the best in most conditions in reality, with absolute errors within 0.75 W. The thermal sub-model approaches the state-of-the-art method with an average relative error of 6.47%. This framework is potential to advance the research and development of PV systems.