Resumo:
The growing interest in solar photovoltaic (PV) energy demands a deep understanding
of module performance under real operating conditions, which often diverge from standard
test conditions. This work presents a robust methodology for characterizing and
modeling the electrical behavior of four distinct PV module technologies: multicrystalline
silicon (mSi), cadmium telluride (CdTe), copper indium gallium selenide (CIGS), and heterojunction
(HIT). The main objective was to investigate the dependence of thermal and
irradiance coefficients on photovoltaic modules, so that the models can be employed in
future performance estimates of photovoltaic arrays under different climatic conditions,
examining the dependence of the five parameters of the single diode model (SDM) as
a function of irradiance and temperature. To this end, experimental data from currentvoltage
I-V curves and a meta-heuristic optimization algorithm—the Self-Adaptive Differential
Evolution (SADE)—were used to extract the model parameters with high precision.
The results of the analysis of the temperature coefficients of the electrical parameters
reveal significant differences in the thermal behavior of the distinct photovoltaic technologies,
reflecting their physical properties and carrier transport and recombination mechanisms.
The photogenerated current (𝐼𝑝ℎ) exhibits positive or slightly negative coefficients,
indicating a moderate increase in current with temperature, more pronounced in CdTe
and mSi and less significant in CIGS.
The saturation current (𝐼0) shows strong thermal dependence in all technologies, contributing
to the reduction in open-circuit voltage, with greater sensitivity observed in
CIGS and mSi. The ideality factor (𝑛) decreases with increasing temperature, with HIT
technology being the most affected, indicating more intense changes in recombination
mechanisms.
Among the resistive parameters, the series resistance (𝑅𝑠) tends to decrease in CdTe and
mSi, while it increases in CIGS and HIT, suggesting a greater impact of ohmic losses in
these technologies. The shunt resistance (𝑅𝑠ℎ) decreases with temperature in all cases,
indicating the intensification of parallel losses, especially in HIT. These results highlight
the importance of considering the specific thermal dependence of each technology for more
realistic modeling and performance prediction under operating conditions.
The irradiance coefficients reveal clear differences in electrical behavior among the photovoltaic
technologies. The photogenerated current (𝐼𝑝ℎ) shows the highest sensitivity to
irradiance in the HIT module, reflecting its high quantum efficiency and low recombination,
while CdTe exhibits the lowest response. The saturation current (𝐼0) shows reduced
variations, being more stable in HIT and more sensitive in CdTe and CIGS, associated
with higher defect density. The ideality factor (𝑛) decreases with irradiance in CdTe and
CIGS, indicating a reduction in non-ideal mechanisms, while it remains practically constant
in HIT. The series (𝑅𝑠) and shunt (𝑅𝑠ℎ) resistances tend to decrease with increasing
irradiance, with more pronounced variations in mSi and CIGS, whereas HIT shows greater
stability, consistent with its heterojunction structure and lower influence of leakage paths.
Thus, the proposed methodology, based on precise parameter extraction through the
SADE algorithm, proves suitable for capturing such dependencies and provides a consistent
basis for more realistic modeling and prediction of the performance of PV modules
and arrays under real climatic conditions. The results obtained in this study contribute
significantly to the literature by providing specific quantitative data that enhance the
accuracy of simulation models. Furthermore, the evidence presented reinforces the potential
of the method for improving the design and optimization of photovoltaic systems
operating under real climatic conditions.