Modeling and optimization of multi-LED solar spectrum synthesis with widely-tuning radiant flux output

Abstract

The spectral power distribution (SPD) of LED was multi-parameters coupled nonlinear function. Spectrum synthesis utilizes multiple type LEDs to match a desired spectrum. By thoroughly exploring and exploiting the properties of SPD under different operational conditions, a modeling and optimization approach for multi-type LED-based AM1.5G solar spectrum synthesis with widely-tuning radiant flux output was proposed in this paper. Specifically, the multi-type LED-based spectrum synthesis modeling was interpreted as an optimization problem of a sum of different LEDs’ SPD, which had to consider multiple parameters coupled each other. Differential evolution algorithm was applied to obtain the optimal operational setpoints of each type of LED. The achievement of synthesized spectra, which closely matched AM1.5G solar spectrum, was obtained using the developed model. Experiments were performed to evaluate the effectiveness of the proposed approach. Three radiant flux outputs of 1.5, 2, and 2.5 W, with a maximum spectral match deviation of 6.53% and maximum relative error of radiant flux output of 3.2%, were obtained in 400 nm–700 nm. The proposed method can provide significant support for the design of multi-LED spectral synthesis application.