Impedance spectroscopy of crystalline silicon solar cell: Observation of negative capacitance

• Published in: Solar energy Vol. 136; pp. 412 - 420
• Main Authors: Panigrahi, Jagannath, Vandana, Singh, Rajbir, Batra, Neha, Gope, Jhuma, Sharma, Mukul, Pathi, P., Srivastava, S.K., Rauthan, C.M.S., Singh, P.K.
• Format: Journal Article
• Language: English
• Published: New York Elsevier Ltd 15-10-2016; Pergamon Press Inc
• Subjects: Crystalline silicon solar cell; Crystals; Impedance spectroscopy; Negative capacitance; Photovoltaic cells; Silicon; Solar energy; Crystalline silicon solar cell; Impedance spectroscopy; Negative capacitance
• ISSN: 0038-092X; 1471-1257
• DOI: 10.1016/j.solener.2016.06.041

•Impedance spectroscopy is used to study industrial silicon solar cell under different bias and illumination.•Pseudo capacitance behaviour is observed in the impedance spectra.•A modified electrical equivalent circuit with inductive component is proposed which fits the experimental data.•The origin of “negative capacitance” is attributed to non-ideal metal-semiconductor contacts.
The knowledge of ac parameters of solar cells/arrays is important for designing of high performance power conditioning circuits to match the input at operating conditions. A systematic study of crystalline silicon solar cells is done using impedance spectroscopy under forward bias conditions and at different illumination levels. A “negative capacitance” behaviour is observed in the low frequency region under forward bias voltages and at low illumination levels. An electrical equivalent circuit with inductive component is used to fit the experimental data and the pseudo-capacitance behaviour is explained on the basis of an equivalent circuit model.