Time and frequency domains characteristics comparative analysis for light output waveform of fault-free and faulty LED lamps

• Published in: Optik (Stuttgart) 2020-12, Vol.223, p.165540, Article 165540
• Main Authors: Sun, Fukang, Fang, Qiansheng, Xie, Jianxia, Chen, Bailing, Shang, Yuhang, Wan, Jin, Song, Pengfei, Fang, Jiuming
• Format: Article
• Language: English
• Subjects: Average value; Characteristics analysis; Coefficient of variation; Frequency spectrum; LED lamps; Light output waveform; Time and frequency domains
• ISSN: 0030-4026; 1618-1336
• DOI: 10.1016/j.ijleo.2020.165540

To discover the fault detection and diagnosis method of LED lamps with the light output waveform, in this paper, the time and frequency domains characteristics of light output waveform among fault-free and faulty LED lamps are extracted, involving average value, coefficient of variation, and frequency spectrum, and the difference are comparative analyzed. Experiment setup is built with Light Flicker Analyzer and integrating sphere, and OSRAM 8.5W LED lamps using linear driver are selected as the experiment samples. The comparative analysis results demonstrate that there are obvious difference among fault-free and faulty LED lamps in the light output waveform. Firstly, after lighting, the average value of light output waveform of faulty LED lamps are obviously lower than fault-free LED lamps. Secondly, after lighting, the coefficient of variation of light output waveform of faulty LED lamps are obviously higher than fault-free LED lamps. Finally, the Fourier spectrum’s base frequency of light output waveform of fault-free LED lamps is 100 Hz, and also including two obvious harmonic components, that are 200 Hz and 300 Hz. However, by comparison with fault-free LED lamps, the Fourier spectrum’s component of faulty LED lamps are more complex, including more obvious harmonic components and noise spectrum. The research results provide the chance for fault detection and diagnosis of LED lamps with optical features.