- 标题
- 摘要
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Influence of slit alignment and slit width on the luminosity measurement of arc discharge channel
摘要： The luminosity of lightning channel is closely related to the lightning current. In the present paper, a lightning channel luminosity detection system (LCLDS), comprising of an avalanche photodiode module, a neutral density ?lter, an extension tube and an adjustable horizontal slit, is assembled. By using the impulse current generator, lightning impulse currents with di?erent amplitudes and also di?erent waveforms were produced in a 15-mm open-air gap between two graphite-rod electrodes. The luminosity and the current of discharge channel were measured synchronously. The experiments looking into the in?uencing factors of luminosity measurement, including the alignment of the silt and the slit width, were carried out. Obtained results show that the slit opening center of LCLDS should be aligned to the center of the discharge gap. Otherwise, in the case of improper alignment, the measured luminosity waveforms associated with the same injected current might be quite dif- ferent in the amplitudes as well as in the waveforms. Moreover, the peak luminosity increases linearly with increasing slit width, whereas the luminosity waveforms are practically una?ected, implying that, in the prac- tical application, the slit width can be adjusted to alter the luminosity signal output according to the actual need. Obtained results here can establish the foundation to develop the correlation between the current and the corresponding luminosity in the future.
关键词： Current,Luminosity,Slit,Optical observation,Lightning
更新于2025-09-10 09:29:36
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[IEEE 2018 34th International Conference on Lightning Protection (ICLP) - Rzeszow (2018.9.2-2018.9.7)] 2018 34th International Conference on Lightning Protection (ICLP) - Optical Lightning Measurement System and First Results
摘要： This paper introduces a newly developed optical lightning measurement system (OLMS). The OLMS is based on a video system using a camera with a 360° panorama view and a frame rate of 60 frames per second. The OLMS locates the lightning from the direction of the illuminated lightning channel and the travel time of the thunder sound. The analysis comprises 34 flashes containing 144 strokes, which occurred during the time period from 30th of July 2017 to 24th of August 2017. The results are compared to data obtained by the European lightning location network EUCLID. The comparison revealed a flash detection efficiency of 100 % and a stroke detection efficiency of 93.1 % for EUCLID. With EUCLID, the fraction of 92.5 % was classified correctly as cloud-to-ground lightning and the minor fraction of 7.5 % was miss-classified as cloud-to-cloud lightning. On average (arithmetic mean), the negative flashes contained 4.3 return strokes with 1.7 different striking points. For multi-stroke flashes with return strokes using the same lightning channel, EUCLID located the individual striking points with a median deviation of 57.3 m. The average striking distance was about 10 km. Due to the far distance the thunder sound could often not be separated from the thunder sound of other lightning. Therefore, the OLMS located the lightning with a relatively high deviation compared to the data of EUCLID. The arithmetic (geometric) mean value of the deviation was 1330 m (670 m).
关键词： optical measurement,detection efficiency,Lightning location system (LLS),multiple lightning flash,location accuracy,selectivity CG/CC
更新于2025-09-09 09:28:46
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[IEEE 2018 34th International Conference on Lightning Protection (ICLP) - Rzeszow (2018.9.2-2018.9.7)] 2018 34th International Conference on Lightning Protection (ICLP) - On In Situ Lightning Current Impulse Testing in a Large Free Field PV Plant
摘要： Lightning ground potential rise (GPR) was shown to be a significant contributor to equipment damage under certain conditions that include, in particular, high soil resistivity. In addition, IEEE Std 1692 suggested that surge protective devices (SPDs) may not protect adequately under conditions of lightning GPR. This paper follows on earlier work that addressed lightning GPR associated with large electrodes, loss of equipotential under conditions of GPR and a desk-top study on the behavior of a low voltage SPD under emulated lightning impulse conditions. The findings of a laboratory test on the behavior of an SPD under lightning current impulse conditions as well as in situ testing of an SPD under lightning current impulse are presented in this paper. The paper concludes by reflecting on initial findings from post-test monitoring under actual lightning, emphasizes the value of in situ testing and points out its limitations.
关键词： current,lightning,free field,in situ,plant,test,photovoltaic,impulse
更新于2025-09-09 09:28:46