Light flicker of fluorescent lamps with different types of ballasts caused by interharmonics
ABSTRACT The paper presents an analysis of the voltage fluctuations caused by interharmonics and its influence on luminous flux fluctuations of used combinations of fluorescent lamps and ballasts. One of the analysis results is a concept determining light sources sensitivity to such disturbing type based on frequency components utilization. Further a complex measured data file of sensitivity curves in various combinations of fluorescent lamps and ballasts are pointed. Measured and compared combinations include various types of fluorescent lamps, various wattages, modes of operation of the ballast and its specific designs and dimensioning of circuit elements etc.
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- "Nevertheless the lamps flickering is produced also by a phase voltage modulation, mainly by phase jumps  and by the interharmonic voltages superimposed on a voltage waveform . A lamp ability to transfer such changes in supply voltage on generated luminous time-spectrum changes is given by its transfer function which depends on the lamp function principle and type as well as on the wiring, circuit designing and dimensioning . From the point of view of the perception of a lamp light variation by a human eye, changes within the range of (0.1 ÷ 35 (40)) Hz are significant. "
Article: A Light-flickermeter–Part I: Design[Show abstract] [Hide abstract]
ABSTRACT: Voltage variation is one of lamps flickering main cause; thus evaluation of a disturbing light flicker is a part of volt-age quality classification. The instrument for flicker level measurement by means of voltage variation analysis is named flickermeter and is specified in standard EN 61000-4-15. The flickermeter is a specialized analyzer modeling response of a chain consisting of reference 60W incandes-cent lamp – eye – brain of an average observer. Hence, other lamp types like discharge are mainly used in illumina-tion systems at present, significant difference between flicker measurement using the standard flickermeter and observation can appear. In the paper, there is proposed a light flicker measurement method based on analysis of an irradiance (radiant flux) waveform, where the output flicker index is independent on the lamp type. With regard to ex-pected properties the proposed light-flickermeter can be called objective flickermeter. Nevertheless the range of application of the objective flickermeter is limited as it is also shown.
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ABSTRACT: The aim of the paper is to describe procedures for systematical determination of immunity of lamps to supply voltage variations caused by interharmonics. The curve of lamp immunity is presented as an interharmonic magnitude versus interharmonic frequency curve and is called interharmonic-flicker curve. The interharmonic-flicker curves of lamps are determined by utilizing a modified concept for measurement of a lamp gain factor in frequency domain and by utilizing the published limits on voltage flicker. Another described method for establishing the interharmonic-flicker curves of lamps is the method based on measuring the luminous flux flicker curve which is defined by utilizing the published limits on voltage flicker as well. Further a complex measured data file of interharmonic-flicker curves in various combinations of discharge lamps (fluorescent lamps and high intensity discharge lamps) and ballasts are pointed. Measured and compared combinations include various types of discharge lamps, various wattages, modes of operation of the ballast and its specific designs and dimensioning of circuit elements etc. Finally, determined interharmonic-flicker curves of chosen lamps are used for proposal approach how to revise the compatibility level for interharmonic voltages relating to flicker.Power Tech, 2007 IEEE Lausanne; 08/2007
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ABSTRACT: The aim of this paper is to propose an improved approach for the measurement of the severity of power quality phenomenon called light flicker which is the disturbance caused by luminance variations due to supply voltage fluctuations. The proposed approach is based directly on light intensity measurements, unlike usual standard approach (IEC EN 61000-4-15), which indirectly determines flicker severity from measuring voltage fluctuations and accounting the response of a standard incandescent lamp (230 V/60 W). Only adopting a direct measurement of light fluctuation is possible to asses flicker severity whatever illuminating device is present, in this way, the implemented sensor is considered to perform an objective measurement of light flicker. To compare performances and metrological characteristics with current standard requirements, a testing station has been implemented and results compared to a standard IEC flickermeter (Norma D6000). Thanks to its small dimensions and weight, the instrument can be used to measure light flicker over a wide range of environments spanning from home/office to industrial locations.Measurement 04/2008; 41(3-41):334-340. DOI:10.1016/j.measurement.2006.09.007 · 1.53 Impact Factor