A Novel Solar Simulator Based on Combined Natural-White and Infrared Light Emitting Diodes

Abstract

Despite the continuous trend of an LED solar simulator development, there was little to be found in the application of a phosphor-converted natural white LED (pc-nWLED) for construction. This article reported the design and construction of an LED solar simulator which combined a pc-nWLED with infrared LEDs. The objectives of this study are to determine the performance of a novel solar simulator including non-uniformity (SNE), temporal stability (TIE), and spectrum mismatch (SM). This is followed by an experimental study of the correlation between the LED’s temperature and SNE. A spectroradiometer, pyranometer, and a custom-made non-uniformity measurement system were applied to test the performance characteristics of this solar simulator. The results indicated that the proposed solar simulator could achieve the AAA class. The results showed 0.90-1.08 of SM, 0.83% TIE, and 1.34% of SNE. The SNE indicated the positive significant correlation with the LED’s temperature, with an approximate of +0.043% per °C. A good cooling system for the LED module was necessary to maintain constant light uniformity. The blue-chip phosphor converted white LED combination with color mixed of 730 nm, 850 nm, and 940 nm could emit a light spectrum that was very close to the reference spectrum of about 99.6%.