Compact Light-Emitting Diode-Based AAA Class Solar Simulator: Design and Application Peculiarities

In this paper, we report on the efficient design of a light-emitting diode (LED)-based AAA class solar simulator, employing only 19 high-power emitters for a usable illuminated area of at least 5 cm in diameter with at least 1 sun irradiance. Such a low number of emitters was achieved by selectively employing secondary optics for several LED groups and taking advantage of wide emission angle for others. The so-called A class spectrum was also achieved for the larger area of more than 6 cm × 6 cm, covering zones with B and C class irradiance nonuniformity. Five distinct solar cell external quantum efficiency spectra were considered for theoretical evaluation of possible measurement peculiarities related to different solar cell technologies. These computer-generated spectra contained essential features, which is typical for high-efficiency crystalline and amorphous silicon, Cu(In,Ga)Se₂, and Cu₂ZnSn(S,Se)₄ solar cell technologies. Significant photocurrent distribution nonuniformity change is predicted only for amorphous silicon cells due to a much narrower efficient absorption spectrum.