Pub Date : 2012-11-12DOI: 10.1109/ICLP.2012.6344237
Y. Liao, L. Jia, Zhizhao Li, R. Zeng, S. Chen
The problem whether the DC operation voltage can influence the characteristics of upward leader emerging from transmission lines is still in question since experiments and observation data is insufficient. It is necessary to study the relationship between the characteristics of the upward leaders and operation voltage. This paper presents some simulated experimental results of a combined plane-rod (PR) electrode to conductor air gap of 7 meter length. A current measuring instrument with frequency response of from DC to 6.5MHz was developed and used to measure the leader current. Besides, high speed CCD camera was used to observe the optical phenomenon of the whole process. The 200/2000μs impulse voltage up to 4MV and positive DC voltage up to 800kV was applied to the electrode and conductor respectively. The higher charge per unit in the leader channel and earlier inception time has been found along the higher DC voltage. These results have been compared with those in the gap that only impulse voltage was applied. Finally, the influence of positive DC voltage on the characteristics of upward leaders was discussed.
{"title":"Research on the characteristics of upward leader emerging from the transmission lines influenced by operation voltage","authors":"Y. Liao, L. Jia, Zhizhao Li, R. Zeng, S. Chen","doi":"10.1109/ICLP.2012.6344237","DOIUrl":"https://doi.org/10.1109/ICLP.2012.6344237","url":null,"abstract":"The problem whether the DC operation voltage can influence the characteristics of upward leader emerging from transmission lines is still in question since experiments and observation data is insufficient. It is necessary to study the relationship between the characteristics of the upward leaders and operation voltage. This paper presents some simulated experimental results of a combined plane-rod (PR) electrode to conductor air gap of 7 meter length. A current measuring instrument with frequency response of from DC to 6.5MHz was developed and used to measure the leader current. Besides, high speed CCD camera was used to observe the optical phenomenon of the whole process. The 200/2000μs impulse voltage up to 4MV and positive DC voltage up to 800kV was applied to the electrode and conductor respectively. The higher charge per unit in the leader channel and earlier inception time has been found along the higher DC voltage. These results have been compared with those in the gap that only impulse voltage was applied. Finally, the influence of positive DC voltage on the characteristics of upward leaders was discussed.","PeriodicalId":400743,"journal":{"name":"2012 International Conference on Lightning Protection (ICLP)","volume":"2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-11-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114952379","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2012-11-12DOI: 10.1109/ICLP.2012.6344402
M. Becerra
Previous studies in the literature have suggested that glow corona discharges could be potentially used to control the frequency of lightning flashes to grounded objects. Such studies use simplified one-dimensional corona drift models or basic empirical equations derived from high voltage experiments to assess the effect of glow corona on the initiation of both streamers and upward connecting leaders under the influence of a descending lightning leader. In order to revisit the theoretical basis of these studies, a two-dimensional glow corona drift model has been implemented together with a self-consistent upward leader inception and propagation model -SLIM-. A 60 m tall lightning rod is used as a study case. It is found that the shielding effect of the glow corona space charge has been strongly overestimated in the literature. Furthermore, it is shown that streamers under the influence of a descending leader are initiated significantly earlier from the cylindrical body rather than from the corona-emitting area of the rod. Considering the effective shielding potential of glow corona, it is also shown that the presence of glow corona reduces the downward lightning attractiveness of 60 m tall lightning rods by less than 15%. This result shows that the efficiency of lightning rods is not strongly influenced by the generation of glow corona as opposed to the suggestions of previous studies.
{"title":"Glow corona discharges and their effect on lightning attachment: Revisited","authors":"M. Becerra","doi":"10.1109/ICLP.2012.6344402","DOIUrl":"https://doi.org/10.1109/ICLP.2012.6344402","url":null,"abstract":"Previous studies in the literature have suggested that glow corona discharges could be potentially used to control the frequency of lightning flashes to grounded objects. Such studies use simplified one-dimensional corona drift models or basic empirical equations derived from high voltage experiments to assess the effect of glow corona on the initiation of both streamers and upward connecting leaders under the influence of a descending lightning leader. In order to revisit the theoretical basis of these studies, a two-dimensional glow corona drift model has been implemented together with a self-consistent upward leader inception and propagation model -SLIM-. A 60 m tall lightning rod is used as a study case. It is found that the shielding effect of the glow corona space charge has been strongly overestimated in the literature. Furthermore, it is shown that streamers under the influence of a descending leader are initiated significantly earlier from the cylindrical body rather than from the corona-emitting area of the rod. Considering the effective shielding potential of glow corona, it is also shown that the presence of glow corona reduces the downward lightning attractiveness of 60 m tall lightning rods by less than 15%. This result shows that the efficiency of lightning rods is not strongly influenced by the generation of glow corona as opposed to the suggestions of previous studies.","PeriodicalId":400743,"journal":{"name":"2012 International Conference on Lightning Protection (ICLP)","volume":"7 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-11-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116168795","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2012-11-12DOI: 10.1109/ICLP.2012.6344307
V. Cooray, G. Cooray
Electromagnetic fields associated with the electric current flowing along a overhead power line with a single conductor located over perfectly conducting ground are estimated using electromagnetic fields pertinent to acceleration of electric charges. It is shown that the electric and magnetic fields that exist below a long overhead power line are nothing but the radiation fields generated by the acceleration of charge at the point of injection of current into the power line.
{"title":"On the electric and magnetic fields below a single conductor overhead power line","authors":"V. Cooray, G. Cooray","doi":"10.1109/ICLP.2012.6344307","DOIUrl":"https://doi.org/10.1109/ICLP.2012.6344307","url":null,"abstract":"Electromagnetic fields associated with the electric current flowing along a overhead power line with a single conductor located over perfectly conducting ground are estimated using electromagnetic fields pertinent to acceleration of electric charges. It is shown that the electric and magnetic fields that exist below a long overhead power line are nothing but the radiation fields generated by the acceleration of charge at the point of injection of current into the power line.","PeriodicalId":400743,"journal":{"name":"2012 International Conference on Lightning Protection (ICLP)","volume":"18 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-11-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116249303","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2012-11-12DOI: 10.1109/ICLP.2012.6344275
F. H. Silveira, S. Visacro, R. E. de Souza, A. De Conti
The Hybrid Electromagnetic Model was used systematically to determine lightning overvoltages across insulator strings due to direct strikes to the tower top in order to assess the importance of subsequent strokes on backflashovers for 138-kV transmission lines. It was found that for some specific conditions, especially for lines with high towers and low tower-footing grounding resistances, subsequent strokes may be a relevant source of lightning outages.
{"title":"Assessing the impact of subsequent strokes on the lightning performance of transmission lines of 138 kV","authors":"F. H. Silveira, S. Visacro, R. E. de Souza, A. De Conti","doi":"10.1109/ICLP.2012.6344275","DOIUrl":"https://doi.org/10.1109/ICLP.2012.6344275","url":null,"abstract":"The Hybrid Electromagnetic Model was used systematically to determine lightning overvoltages across insulator strings due to direct strikes to the tower top in order to assess the importance of subsequent strokes on backflashovers for 138-kV transmission lines. It was found that for some specific conditions, especially for lines with high towers and low tower-footing grounding resistances, subsequent strokes may be a relevant source of lightning outages.","PeriodicalId":400743,"journal":{"name":"2012 International Conference on Lightning Protection (ICLP)","volume":"351 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-11-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123386182","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2012-11-12DOI: 10.1109/ICLP.2012.6344344
S. Wyderka, G. Masłowski, R. Ziemba, G. Karnas
Investigations were conducted aimed on examination of frequency characteristics of middle to low voltage distribution transformer used to supply residential buildings. Two methods were used for the investigations. First, the impedances (absolute values and angles) of transformer middle and low voltage windings were measured and registered using precision LCR meter for frequency range from 20 Hz to 10 MHz. These impedance characteristics were also examined using voltage surge generator and digital oscilloscope. Registered voltage and current waveforms were denoised and transformed to frequency domain. Apart from investigation of distribution transformer the frequency characteristic of input impedances of typical household electrical appliances were examined using the LCR meter. The conducted measurements are significant part of investigations concerning the lightning and overvoltage protection of residential buildings, which are conducted at the test site belonging to Rzeszow University of Technology.
{"title":"Frequency characteristics of supplying transformer and electrical appliances of residential building in modeling of lightning current distribution","authors":"S. Wyderka, G. Masłowski, R. Ziemba, G. Karnas","doi":"10.1109/ICLP.2012.6344344","DOIUrl":"https://doi.org/10.1109/ICLP.2012.6344344","url":null,"abstract":"Investigations were conducted aimed on examination of frequency characteristics of middle to low voltage distribution transformer used to supply residential buildings. Two methods were used for the investigations. First, the impedances (absolute values and angles) of transformer middle and low voltage windings were measured and registered using precision LCR meter for frequency range from 20 Hz to 10 MHz. These impedance characteristics were also examined using voltage surge generator and digital oscilloscope. Registered voltage and current waveforms were denoised and transformed to frequency domain. Apart from investigation of distribution transformer the frequency characteristic of input impedances of typical household electrical appliances were examined using the LCR meter. The conducted measurements are significant part of investigations concerning the lightning and overvoltage protection of residential buildings, which are conducted at the test site belonging to Rzeszow University of Technology.","PeriodicalId":400743,"journal":{"name":"2012 International Conference on Lightning Protection (ICLP)","volume":"20 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-11-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124958708","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2012-11-12DOI: 10.1109/ICLP.2012.6344353
T. Gazizov, A. Zabolotsky, A. Melkozerov, E. S. Dolganov, P. Orlov
A new approach to the protection of electronics is considered to comply better with the requirements of lightning protection. Input power distribution in modal filter (MF) resistive terminations is analyzed. Dependencies of the MF power dissipation on the excitation pulse parameters have been obtained for 1-, 2-, 3-, 4-stage MF with fixed total length. Conclusions reveal potentially vulnerable parts which should be improved in order to prevent the MF failure due to overload of certain parts.
{"title":"Analysis of power dissipation in resistive terminations of single- and multistage modal filters","authors":"T. Gazizov, A. Zabolotsky, A. Melkozerov, E. S. Dolganov, P. Orlov","doi":"10.1109/ICLP.2012.6344353","DOIUrl":"https://doi.org/10.1109/ICLP.2012.6344353","url":null,"abstract":"A new approach to the protection of electronics is considered to comply better with the requirements of lightning protection. Input power distribution in modal filter (MF) resistive terminations is analyzed. Dependencies of the MF power dissipation on the excitation pulse parameters have been obtained for 1-, 2-, 3-, 4-stage MF with fixed total length. Conclusions reveal potentially vulnerable parts which should be improved in order to prevent the MF failure due to overload of certain parts.","PeriodicalId":400743,"journal":{"name":"2012 International Conference on Lightning Protection (ICLP)","volume":"13 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-11-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129046054","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2012-11-12DOI: 10.1109/ICLP.2012.6344335
Y. Naito
As a method for protecting electronic equipments from lightning attacks, mounting of SPD (surge protective device) which consists of a gas discharge tube (GDT), metal oxide varistor (MOV), and others is useful. In protecting equipment by SPD, overvoltage protection and energy harmonization become important. Above all, when overvoltage protection is thought of, response characteristics become important. Response characteristics depend on wavefront length and peak value applied to the equipment. In this paper, using 5 types of GDT, experiments were conducted on response characteristics when voltage waveforms having varying wavefront lengths were applied to investigate the response characteristics. Specially, the response characteristics for steep wavefront are specified.
{"title":"Response characteristics of diode gas discharge tubes","authors":"Y. Naito","doi":"10.1109/ICLP.2012.6344335","DOIUrl":"https://doi.org/10.1109/ICLP.2012.6344335","url":null,"abstract":"As a method for protecting electronic equipments from lightning attacks, mounting of SPD (surge protective device) which consists of a gas discharge tube (GDT), metal oxide varistor (MOV), and others is useful. In protecting equipment by SPD, overvoltage protection and energy harmonization become important. Above all, when overvoltage protection is thought of, response characteristics become important. Response characteristics depend on wavefront length and peak value applied to the equipment. In this paper, using 5 types of GDT, experiments were conducted on response characteristics when voltage waveforms having varying wavefront lengths were applied to investigate the response characteristics. Specially, the response characteristics for steep wavefront are specified.","PeriodicalId":400743,"journal":{"name":"2012 International Conference on Lightning Protection (ICLP)","volume":"65 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-11-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129332099","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2012-11-12DOI: 10.1109/ICLP.2012.6344321
C. Mata, A. G. Mata
A Lightning Protection System (LPS) was designed and built at Launch Complex 39B (LC39B), at the Kennedy Space Center (KSC), Florida in 2009. This LPS was instrumented with comprehensive meteorological and lightning data acquisition systems that were deployed from late 2010 until mid 2011. The first direct strikes to the LPS were recorded in March of 2011, when a limited number of sensors had been activated. The lightning instrumentation system detected a total of 70 nearby strokes and 19 direct strokes to the LPS, in 2011, 2 of the 19 direct strokes to the LPS had two simultaneous ground attachment points (in both instances one channel terminated on the LPS and the other on the nearby ground). In addition to the 70 nearby strokes, some more distant nearby strokes where captured on video records for which limited data were acquired. Instrumentation deployment chronological milestones, a summary of lightning strikes (direct and nearby), high speed video frames, downconductor currents, and dH/dt and dE/dt typical waveforms for direct and nearby strokes are presented in this paper.
{"title":"Summary of 2011 direct and nearby lightning strikes to Launch Complex 39B, Kennedy Space Center, Florida","authors":"C. Mata, A. G. Mata","doi":"10.1109/ICLP.2012.6344321","DOIUrl":"https://doi.org/10.1109/ICLP.2012.6344321","url":null,"abstract":"A Lightning Protection System (LPS) was designed and built at Launch Complex 39B (LC39B), at the Kennedy Space Center (KSC), Florida in 2009. This LPS was instrumented with comprehensive meteorological and lightning data acquisition systems that were deployed from late 2010 until mid 2011. The first direct strikes to the LPS were recorded in March of 2011, when a limited number of sensors had been activated. The lightning instrumentation system detected a total of 70 nearby strokes and 19 direct strokes to the LPS, in 2011, 2 of the 19 direct strokes to the LPS had two simultaneous ground attachment points (in both instances one channel terminated on the LPS and the other on the nearby ground). In addition to the 70 nearby strokes, some more distant nearby strokes where captured on video records for which limited data were acquired. Instrumentation deployment chronological milestones, a summary of lightning strikes (direct and nearby), high speed video frames, downconductor currents, and dH/dt and dE/dt typical waveforms for direct and nearby strokes are presented in this paper.","PeriodicalId":400743,"journal":{"name":"2012 International Conference on Lightning Protection (ICLP)","volume":"32 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-11-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130693893","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2012-11-12DOI: 10.1109/ICLP.2012.6344250
N. Rameli, M. Kadir, M. Izadi, Chandima Gomes, J. Jasni
This paper investigates the influence of inclined lightning channel on induced voltage on the line. The angle variations of inclined lightning channel may cause the voltage to be induced at different values for different points along the power line. This behaviour may affect the line's lightning performance if the peak of induced voltage is greater than the critical flashover voltage (CFO) of the line. This induced voltage is expected to be increased when the inclined angle with respect to the observation point is decreased. Appropriate method of induced voltage algorithm with respect to the incline lightning channel will be developed and compared with other method. The outcome of this study would be useful for the utility for their planning and selection of appropriate protection scheme for the line.
{"title":"On the influence of inclined lightning channel on lightning induced voltage evaluation","authors":"N. Rameli, M. Kadir, M. Izadi, Chandima Gomes, J. Jasni","doi":"10.1109/ICLP.2012.6344250","DOIUrl":"https://doi.org/10.1109/ICLP.2012.6344250","url":null,"abstract":"This paper investigates the influence of inclined lightning channel on induced voltage on the line. The angle variations of inclined lightning channel may cause the voltage to be induced at different values for different points along the power line. This behaviour may affect the line's lightning performance if the peak of induced voltage is greater than the critical flashover voltage (CFO) of the line. This induced voltage is expected to be increased when the inclined angle with respect to the observation point is decreased. Appropriate method of induced voltage algorithm with respect to the incline lightning channel will be developed and compared with other method. The outcome of this study would be useful for the utility for their planning and selection of appropriate protection scheme for the line.","PeriodicalId":400743,"journal":{"name":"2012 International Conference on Lightning Protection (ICLP)","volume":"50 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-11-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131202708","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2012-11-12DOI: 10.1109/ICLP.2012.6344414
S. Buba, C. Gomes, M. A. Ab. Kadir
Lightning related accidents in Nigeria, a country of high lightning density, have been collected and analyzed. Results show that lightning related human injuries and deaths are very high in Nigeria, where the actual figure may reach as high as 500 deaths per year. However, due to the social stigma attached to lightning incidents and the lack of unbroken news chains reaching media, collection of accurate statistics has become a daunting task. Apart from human and livestock related hazards; property damage is also of high concern due to probable devastating consequences of such incidents. Extra attention has been paid on collecting damage records related to aviation industry as there are several serious accidents related to lightning have been reported in this area. The data collected and analysed is used to develop a set of national level recommendations for lighting safety and protection which can also be applicable in neighbouring countries, as they also experience extremely high lightning occurrence density.
{"title":"Lightning accidents in Nigeria: With special attention to aviation mishaps","authors":"S. Buba, C. Gomes, M. A. Ab. Kadir","doi":"10.1109/ICLP.2012.6344414","DOIUrl":"https://doi.org/10.1109/ICLP.2012.6344414","url":null,"abstract":"Lightning related accidents in Nigeria, a country of high lightning density, have been collected and analyzed. Results show that lightning related human injuries and deaths are very high in Nigeria, where the actual figure may reach as high as 500 deaths per year. However, due to the social stigma attached to lightning incidents and the lack of unbroken news chains reaching media, collection of accurate statistics has become a daunting task. Apart from human and livestock related hazards; property damage is also of high concern due to probable devastating consequences of such incidents. Extra attention has been paid on collecting damage records related to aviation industry as there are several serious accidents related to lightning have been reported in this area. The data collected and analysed is used to develop a set of national level recommendations for lighting safety and protection which can also be applicable in neighbouring countries, as they also experience extremely high lightning occurrence density.","PeriodicalId":400743,"journal":{"name":"2012 International Conference on Lightning Protection (ICLP)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-11-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131203946","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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