Impedance Spectroscopy for partial shading detection on series-connected PV panels

This work investigates an improved method for detecting and simulating the effect of partial shading on photovoltaic (PV) panels by combining experimental and simulation procedures. The method entails measuring current-voltage (IV) curves and impedance spectra for two Photovoltaic (PV) panels under outdoor conditions. The shade is then recreated in one panel, and measurements are repeated to generate a dataset for adjusting a Constant Phase Element (CPE). In addition, the single-diode model (SDM) is tested using the SPICE environment for further validation. Experiments are repeated at different irradiances and operation points to fully understand PV panel performance in diverse environments. The paper focuses on the experimental outcomes. This study examines tuning a CPE model based on experimental data and using the single-diode model in SPICE simulations. The study's comprehensiveness is demonstrated by presenting data for various irradiances and operating points. The improved CPE model's reliability and precision, as well as validation of the single diode model in SPICE, are emphasized. The findings from the experiments contribute to better comprehension of PV panel dynamics in non-uniform scenarios. The importance of reproducing these results in simulation for engineering applications is emphasized, providing the path for future advances in PV panel design and optimization based on spectrum measurements.