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Publication Citation: Evaluation and Validation of Equivalent Circuit Photovoltaic Solar Cell Performance Models

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Author(s): Matthew T. Boyd; S. A. Klein; Douglas T. Reindl; Brian P. Dougherty;
Title: Evaluation and Validation of Equivalent Circuit Photovoltaic Solar Cell Performance Models
Published: May 01, 2011
Abstract: The ,Five-Parameter ModelŠ is an electrical performance model for photovoltaic solar cells that predicts the voltage and current output by representing the cells as an equivalent electrical circuit with radiation and temperature dependent components. An important feature of the five-parameter model is that its parameters can be determined using data commonly provided by module manufacturers on their published datasheets. This research evaluated the predictive capability of the five-parameter model and modifications using approximately thirty days of field-measured meteorological and module data from a wide range of cell technologies including: monocrystalline, polycrystalline, and amorphous silicon and copper indium diselenide (CIS). The five-parameter model is capable of predicting the performance of a monocrystalline and a polycrystalline silicon module within approximately 6% RMS, but is slightly less accurate for a thin-film CIS and an amorphous silicon array. Errors for the amorphous technology are reduced to approximately 5% RMS by using input data obtained after the module underwent an initial degradation in output due to aging. The robustness and possible improvements to the five parameter model were evaluated. For example, a sensitivity analysis of the five-parameter model shows that model inputs that are difficult to determine and not provided by manufacturer datasheets ‹ such as glazing material properties, the semiconductor band gap energy, and the ground reflectance ‹ may be represented by single values that can be used for every technology. Modifications to the five-parameter model investigated during this research did not appreciably improve overall model performance. Additional dependence introduced by a seven-parameter model had less than a 1% RMS effect on maximum power predictions for the amorphous technology and increased the modeling errors for this array 4% RMS at open-circuit conditions. Adding a current sink to the equivalent cir
Citation: Journal of Solar Energy Engineering-Transactions of the ASME
Volume: 133
Issue: 2
Pages: 13 pp.
Keywords: solar photovoltaic, computer model, electrical performance, solar module
Research Areas: Solar
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