The capacitance is one of the key dynamic parameters of solar cells, which can provide\nessential information regarding the quality and health state of the cell. However, the measurement\nof this parameter is not a trivial task, as it typically requires high accuracy instruments using, e.g.,\nelectrical impedance spectroscopy (IS). This paper introduces a simple and effective method to\ndetermine the electric capacitance of the solar cells. An RLC (Resistor Inductance Capacitor) circuit is\nformed by using an inductor as a load for the solar cell. The capacitance of the solar cell is found\nby measuring the frequency of the damped oscillation that occurs at the moment of connecting the\ninductor to the solar cell. The study is performed through simulation based on National Instruments\n(NI) Multisim application as SPICE simulation software and through experimental capacitance\nmeasurements of a monocrystalline silicon commercial solar cell and a photovoltaic panel using\nthe proposed method. The results were validated using impedance spectroscopy. The differences\nbetween the capacitance values obtained by the two methods are of 1% for the solar cells and of\n9.6% for the PV panel. The irradiance level effect upon the solar cell capacitance was studied obtaining\nan increase in the capacitance in function of the irradiance. By connecting different inductors to\nthe solar cell, the frequency effect upon the solar cell capacitance was studied noticing a very small\ndecrease in the capacitance with the frequency. Additionally, the temperature effect over the solar cell\ncapacitance was studied achieving an increase in capacitance with temperature.
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