Multijunction solar cell model for translating I-V characteristics as a function of irradiance, spectrum, and cell temperature

We describe here a lumped diode model for concentrator multijunction solar cells, in which the temperature, irradiance and spectrum dependences are explicitly included. Moreover an experimental method based on it for the prediction of the I-V curve under any irradiance-spectrum-temperature conditions from a single input measurement is proposed and applied to a set of commercial triple-junction solar cells in order to demonstrate its validity. Component 'isotype' cells are used as reference cells for intensity and spectrum, sparing the measurement of light spectrum and cell spectral response. Finally, a mean RMS prediction error of 0.85% over a range of 100X-25 degrees C to 700X-75 degrees C is reported for the whole set when the model parameters inherent in the cell are assumed to be the same for every sample. If optimum parameters are extracted for every cell, the RMS error is reduced to 0.53%. Copyright (C) 2010 John Wiley & Sons, Ltd.