Measurement Uncertainties in the Calibration of Multi-Junction Solar Cells using Different Sun Simulators and Reference Devices

A dual-junction solar cell (Perovskite/Silicon) is used in an investigation of measurement uncertainty under standard test conditions. A method traceable to international standards is presented that allows to evaluate uncertainties in the calibration of multi-junction photovoltaic devices. In view of new tandem solar cell concepts the determination of measurement uncertainty for multi-junction solar cells becomes increasingly important. Little has been published so far on this topic. The spectral mismatch factor matrix is introduced to evaluate the influence of different simulator spectra and reference devices on the overall uncertainty of the measurement. For this purpose a Monte Carlo method including wavelength correlations is applied for realistic simulation of the measurement. The uncertainty budget of the calibration of the sun simulator is discussed for uncertainties of the devicés short-circuit current, including effects by luminescent coupling and shunted subcells.