IT Home February 11 news, according to the Chinese Academy of Sciences Suzhou Institute of Biomedical Engineering and Technology news, recently, Suzhou Medical Institute Xiong Daxi team in the field of LED solar simulation technology progress.
According to reports, ground solar radiation is greatly affected by environmental factors such as atmosphere, time, geography, and climate, and it is difficult to obtain stable, repeatable, and controllable sunlight in time, and it is impossible to meet the requirements of quantitative experiments, instrument calibration, and performance testing. Therefore, solar simulators are often used as experimental or calibration equipment to simulate the physical and geometric properties of solar radiation. Light-emitting diodes (LEDs) have gradually become hot light sources for solar simulators with their characteristics of high efficiency and environmental protection, safety and stability. At present, the LED solar simulator mainly realizes the simulation of 3A characteristics on a specific plane and the changing ground solar spectrum, and it is difficult to simulate the geometric characteristics of sunlight under the requirements of a solar constant (100mW/cm2) illuminance.
Xiong Daxi's team at Suzhou Institute of Biomedical Engineering and Technology, Chinese Academy of Sciences, designed a distributed high thermal conductivity single crystal COB package based on a high-power vertical structure narrowband LED light source, which achieved a stable output of high optical power density. At the same time, a method of collecting light from the full aperture of high-power LEDs using a superhemispheric Qiming lens is proposed, and a set of curved multi-source integral collimation system is built, which completes the collimation and uniformity of the full-spectrum light source in the volume space range. The researchers used polycrystalline silicon solar cells to conduct control experiments on the sun simulator under outdoor sunlight and equal conditions, and verified the spectral accuracy and orientation consistency of the solar simulator.
The solar simulator proposed in the study achieves AAA illumination and 1 solar constant irradiance in at least 5cm × 5cm test planes. In the center of the beam, with a working distance of 5cm to 10cm, the irradiance volume space inhomogeneity is less than 0.2%, the collimated beam divergence angle is ±3°, and the irradiance time instability is less than 0.3%. Uniform illumination can be achieved over the volume space range, with the output beam satisfying the cosine law in the test area. In addition, the researchers also developed any solar spectral fitting and control software, which for the first time realized the simultaneous simulation of the ground solar spectrum and the solar azimuth under different conditions. These characteristics make it an important research tool in the solar photovoltaic industry, photochemistry, photobiology and other fields.
IT House learned that the research results were published in Solar Energy under the title of LED-based solar simulator for terrestrial solar spectra and orientations.