Pub Date : 2022-10-02DOI: 10.1109/ICLP56858.2022.9942456
Surekha Jonnalagadda, U. Kumar
Lightning discharges in the atmosphere can present a severe electromagnetic threat to an aircraft in flight. For testing electrical equipment as well as to verify adequacy of protective systems, lightning current waveforms are suggested in pertinent standards. These have been emerged from ground-based lightning measurements and are broadly categorized into fast, median, slow (first and subsequent strokes). Similarly, lightning current waveforms A to D for direct effects are in force in aerospace industry for certification. Waveforms A and D have rise times of median first and subsequent strokes. Component H (fast subsequent stroke) specified in standards, although is not intended for full aircraft level testing but is usually employed for indirect effect testing. Experimental methods for quantification of a lightning threat to aircraft is expensive and time-consuming. Considering the suitability of numerical computational tools for this purpose, in literature, the solution of full-wave equations using Finite Difference Time Domain (FDTD) is considered. Seeking full wave solution for aircraft's complicated geometry would be computationally challenging. As certification for direct effects of aircraft and its major parts involve only the components A and D, in this work, an assessment is made on wave effects based on frequency spectrum of these currents and typical dimensions of aircraft. It is shown that solution of diffusion equation (eddy current field) would be quite adequate for assessing lightning effects on the aircraft. For the sake of completeness, the effect of employing an eddy current approximation for fast subsequent strokes i.e. component H is also analyzed. For these currents, fields are computed on highly simplified wire-mesh model using Time Domain Thin Wire (TDTW) solution and distributed circuit-based approach.
{"title":"Identification of Suitable Governing Equation for Electromagnetic Fields in Aircrafts During a Lightning Strike","authors":"Surekha Jonnalagadda, U. Kumar","doi":"10.1109/ICLP56858.2022.9942456","DOIUrl":"https://doi.org/10.1109/ICLP56858.2022.9942456","url":null,"abstract":"Lightning discharges in the atmosphere can present a severe electromagnetic threat to an aircraft in flight. For testing electrical equipment as well as to verify adequacy of protective systems, lightning current waveforms are suggested in pertinent standards. These have been emerged from ground-based lightning measurements and are broadly categorized into fast, median, slow (first and subsequent strokes). Similarly, lightning current waveforms A to D for direct effects are in force in aerospace industry for certification. Waveforms A and D have rise times of median first and subsequent strokes. Component H (fast subsequent stroke) specified in standards, although is not intended for full aircraft level testing but is usually employed for indirect effect testing. Experimental methods for quantification of a lightning threat to aircraft is expensive and time-consuming. Considering the suitability of numerical computational tools for this purpose, in literature, the solution of full-wave equations using Finite Difference Time Domain (FDTD) is considered. Seeking full wave solution for aircraft's complicated geometry would be computationally challenging. As certification for direct effects of aircraft and its major parts involve only the components A and D, in this work, an assessment is made on wave effects based on frequency spectrum of these currents and typical dimensions of aircraft. It is shown that solution of diffusion equation (eddy current field) would be quite adequate for assessing lightning effects on the aircraft. For the sake of completeness, the effect of employing an eddy current approximation for fast subsequent strokes i.e. component H is also analyzed. For these currents, fields are computed on highly simplified wire-mesh model using Time Domain Thin Wire (TDTW) solution and distributed circuit-based approach.","PeriodicalId":403323,"journal":{"name":"2022 36th International Conference on Lightning Protection (ICLP)","volume":"28 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-10-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116178228","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 : 2022-10-02DOI: 10.1109/ICLP56858.2022.9942485
W. D. van Schalkwyk, Chandima Gomes, J. Van Coller
The effect of Cloud-to-Cloud (CC) lightning on Medium Voltage (MV) lines has previously been assumed to be negligible due to the distance between the line and the CC lightning channel [1]. During a study [2] to distinguish between nearby Cloud-to-Ground (CG) lightning and direct lightning strikes to a 714 km (including branches) 22 kV line, lightning-related line faults were measured also where only CC lightning was present. These line faults were investigated and the network and CC lightning were modelled. It was found that the faults were initiated by CC lightning but that the flashover could be attributed to insufficient wet creepage distance and not due to insufficient Basic Insulation Level (BIL).
{"title":"The Effect of Cloud-to-Cloud Lightning on Medium Voltage Lines","authors":"W. D. van Schalkwyk, Chandima Gomes, J. Van Coller","doi":"10.1109/ICLP56858.2022.9942485","DOIUrl":"https://doi.org/10.1109/ICLP56858.2022.9942485","url":null,"abstract":"The effect of Cloud-to-Cloud (CC) lightning on Medium Voltage (MV) lines has previously been assumed to be negligible due to the distance between the line and the CC lightning channel [1]. During a study [2] to distinguish between nearby Cloud-to-Ground (CG) lightning and direct lightning strikes to a 714 km (including branches) 22 kV line, lightning-related line faults were measured also where only CC lightning was present. These line faults were investigated and the network and CC lightning were modelled. It was found that the faults were initiated by CC lightning but that the flashover could be attributed to insufficient wet creepage distance and not due to insufficient Basic Insulation Level (BIL).","PeriodicalId":403323,"journal":{"name":"2022 36th International Conference on Lightning Protection (ICLP)","volume":"77 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-10-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126866821","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 : 2022-10-02DOI: 10.1109/ICLP56858.2022.9942488
M. A. Alves, B. A. Oliveira, Willian Maia, Waterson S. Soares, Douglas B. da S. Ferreira, Ana P. P. dos Santos, Fernando P. Silvestrow, Eugenio L. Daher, O. P. Júnior
In this paper we describe a new methodology for generating real-time lightning warning prediction by using a reliable multi-source data. To do so, it was used two years of data covering 50km radius over three regions in Brazil. For 5-minutes intervals, it was evaluated three approaches: a rule-based model that monitors an area of radius greater than the protected area, a machine learning model that considers the amount of lightning that hit small nearby regions, and an integrated approach that combines the two above. The results achieved, on average, about 80% of false alarm ratio, when the model generated an alert but no lightning strikes the area, 14% of failures, opposite to the previous one, had lightning without alert, 1% of the total time operations had to be stopped because of alerts, and 9 minutes of lead time between the generation of the alert and there is a lightning strike. A multi-criteria decision method was used to rank the best method for each location. Rule-based and Integrated models were preferred according to the importance of each criterion for stakeholders. Each methodology has its advantages and they can be extended to other areas according to business needs.
{"title":"Lightning Warning Prediction with Multi-source Data","authors":"M. A. Alves, B. A. Oliveira, Willian Maia, Waterson S. Soares, Douglas B. da S. Ferreira, Ana P. P. dos Santos, Fernando P. Silvestrow, Eugenio L. Daher, O. P. Júnior","doi":"10.1109/ICLP56858.2022.9942488","DOIUrl":"https://doi.org/10.1109/ICLP56858.2022.9942488","url":null,"abstract":"In this paper we describe a new methodology for generating real-time lightning warning prediction by using a reliable multi-source data. To do so, it was used two years of data covering 50km radius over three regions in Brazil. For 5-minutes intervals, it was evaluated three approaches: a rule-based model that monitors an area of radius greater than the protected area, a machine learning model that considers the amount of lightning that hit small nearby regions, and an integrated approach that combines the two above. The results achieved, on average, about 80% of false alarm ratio, when the model generated an alert but no lightning strikes the area, 14% of failures, opposite to the previous one, had lightning without alert, 1% of the total time operations had to be stopped because of alerts, and 9 minutes of lead time between the generation of the alert and there is a lightning strike. A multi-criteria decision method was used to rank the best method for each location. Rule-based and Integrated models were preferred according to the importance of each criterion for stakeholders. Each methodology has its advantages and they can be extended to other areas according to business needs.","PeriodicalId":403323,"journal":{"name":"2022 36th International Conference on Lightning Protection (ICLP)","volume":"77 5 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-10-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131073324","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 : 2022-10-02DOI: 10.1109/ICLP56858.2022.9942641
C. Schumann, Hugh G. P. Hunt, Jason Smitt, T. Warner
Upward flashes are one of the most increasing topics of study in the lightning science community, due to the increase of tall structures, such as tall wind turbines and tall buildings. During the period from January 2017 to January 2020, a total of 99 upward flashes were observed in Johannesburg, South Africa. This paper presents the analysis of prior activity observed by high- speed cameras as well as the polarity of the leader and other leader characteristics. The data from lightning location network associated with the cases is also presented in this paper. The cases showed an initial continuous current duration of 417.3ms, and during this continuous current the presence of 1,000 ICC pulses was observed. Another characteristic observed was that 41 % of the cases had subsequent return strokes and that the average duration of the subsequent return strokes was 22ms, and only 10% were longer than 40ms (as per definition of long continuing current).
{"title":"Optical Observations of 99 Upward Flashes in Johannesburg, South Africa","authors":"C. Schumann, Hugh G. P. Hunt, Jason Smitt, T. Warner","doi":"10.1109/ICLP56858.2022.9942641","DOIUrl":"https://doi.org/10.1109/ICLP56858.2022.9942641","url":null,"abstract":"Upward flashes are one of the most increasing topics of study in the lightning science community, due to the increase of tall structures, such as tall wind turbines and tall buildings. During the period from January 2017 to January 2020, a total of 99 upward flashes were observed in Johannesburg, South Africa. This paper presents the analysis of prior activity observed by high- speed cameras as well as the polarity of the leader and other leader characteristics. The data from lightning location network associated with the cases is also presented in this paper. The cases showed an initial continuous current duration of 417.3ms, and during this continuous current the presence of 1,000 ICC pulses was observed. Another characteristic observed was that 41 % of the cases had subsequent return strokes and that the average duration of the subsequent return strokes was 22ms, and only 10% were longer than 40ms (as per definition of long continuing current).","PeriodicalId":403323,"journal":{"name":"2022 36th International Conference on Lightning Protection (ICLP)","volume":"68 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-10-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134027119","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 : 2022-10-02DOI: 10.1109/ICLP56858.2022.9942613
Kazuo Yamamoto, Hiroaki Kazui, Shota Izuchi
There are usually no high structures that block the wind around a wind turbine. Therefore, wind turbines are often struck by lightning. From such a background, “Interpretation of technical standards for wind power generation systems” was revised in Japan, it was obligatory to stop the operation of the wind turbine with an emergency stop system and to restart the operation after confirming the soundness when a lightning detection system installed on the wind turbine detects a lightning strike. But it may take time to restart because sometimes it is difficult to visit the wind turbine for immediate inspection after stopping. In this paper, we investigated the influence of lightning strikes to wind turbines on the availability. In order to consider countermeasures to improve the availability, it is necessary to understand lightning damage situations of the wind turbine. According to the periodic safety management review system in Japan, blade inspection data and maintenance data of each wind turbine had to be recorded. Based on these data, we also report the relationship between lightning damage and lightning parameters.
{"title":"Influence of Lightning Strike on Availability of Wind Turbine and its Damage Analysis","authors":"Kazuo Yamamoto, Hiroaki Kazui, Shota Izuchi","doi":"10.1109/ICLP56858.2022.9942613","DOIUrl":"https://doi.org/10.1109/ICLP56858.2022.9942613","url":null,"abstract":"There are usually no high structures that block the wind around a wind turbine. Therefore, wind turbines are often struck by lightning. From such a background, “Interpretation of technical standards for wind power generation systems” was revised in Japan, it was obligatory to stop the operation of the wind turbine with an emergency stop system and to restart the operation after confirming the soundness when a lightning detection system installed on the wind turbine detects a lightning strike. But it may take time to restart because sometimes it is difficult to visit the wind turbine for immediate inspection after stopping. In this paper, we investigated the influence of lightning strikes to wind turbines on the availability. In order to consider countermeasures to improve the availability, it is necessary to understand lightning damage situations of the wind turbine. According to the periodic safety management review system in Japan, blade inspection data and maintenance data of each wind turbine had to be recorded. Based on these data, we also report the relationship between lightning damage and lightning parameters.","PeriodicalId":403323,"journal":{"name":"2022 36th International Conference on Lightning Protection (ICLP)","volume":"9 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-10-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133165979","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 : 2022-10-02DOI: 10.1109/ICLP56858.2022.9942494
Biagione Rangel de Araújo
This article presents a study on the values of the partitioning coefficient kc of the lightning current amongst the air-terminations/down-conductors, which depend on the type of air-termination system established by the Brazilian and International Standards for Lightning Protection Systems. For the present study, a model was developed by means of specific arrangements of inductive impedances for several specific configurations. However, the arrangements do not cover evaluations of electromagnetic couplings with installations or metallic parts inside structures or buildings. Such model is detailed throughout the paper. The methodology used converts the length of the conductor's air-terminations system and down-conductor into equivalent inductances. An equivalent circuit of inductive impedances was elaborated from the cited model. And from this, equations were synthesized, and tables where the shown kc values calculated from the modeling and compared with the values were simulated with the software ATPDraw 6.0. The values calculated by the equations established according to the mentioned standards. The obtained results converge between the values simulated and calculated by equations and have a significant deviation of up to 57% in relation to the values simulated by the equations of the standards mentioned, depending on the length of the down-conductors. Considering such information and considering that the safety distance or separation distance 's' is directly related to the ‘kc’ factor, the conclusion is to recommend an evaluation of the equations for the calculation of such factor. Thus, in our understanding, the safety distance will be more effective for mitigating dangerous sparks that could cause damage to people and structures.
{"title":"Study of kc coefficient values established in the Brazilian and International Standards for Lightning Protection Systems","authors":"Biagione Rangel de Araújo","doi":"10.1109/ICLP56858.2022.9942494","DOIUrl":"https://doi.org/10.1109/ICLP56858.2022.9942494","url":null,"abstract":"This article presents a study on the values of the partitioning coefficient kc of the lightning current amongst the air-terminations/down-conductors, which depend on the type of air-termination system established by the Brazilian and International Standards for Lightning Protection Systems. For the present study, a model was developed by means of specific arrangements of inductive impedances for several specific configurations. However, the arrangements do not cover evaluations of electromagnetic couplings with installations or metallic parts inside structures or buildings. Such model is detailed throughout the paper. The methodology used converts the length of the conductor's air-terminations system and down-conductor into equivalent inductances. An equivalent circuit of inductive impedances was elaborated from the cited model. And from this, equations were synthesized, and tables where the shown kc values calculated from the modeling and compared with the values were simulated with the software ATPDraw 6.0. The values calculated by the equations established according to the mentioned standards. The obtained results converge between the values simulated and calculated by equations and have a significant deviation of up to 57% in relation to the values simulated by the equations of the standards mentioned, depending on the length of the down-conductors. Considering such information and considering that the safety distance or separation distance 's' is directly related to the ‘kc’ factor, the conclusion is to recommend an evaluation of the equations for the calculation of such factor. Thus, in our understanding, the safety distance will be more effective for mitigating dangerous sparks that could cause damage to people and structures.","PeriodicalId":403323,"journal":{"name":"2022 36th International Conference on Lightning Protection (ICLP)","volume":"29 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-10-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133422923","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 : 2022-10-02DOI: 10.1109/ICLP56858.2022.9942509
M. Talbi, K. Arzag, Z. Azzouz
In this work, we are interested in the study of the lightning return stroke current distribution along a tall object namely a tower and along the lightning channel. The considered tower is that of Peissenberg in Germany. To carry out this study, we have developed a computer code based on the use of electromagnetic models and the three dimensions finite difference time domain (3D-FDTD) method. The latter is combined to UMPL boundary conditions and is based on Taflove formulation. The program was developed in MATLAB environment. So, in this study electromagnetic models have two configurations. The first one is that adopted for the Peissenberg tower, in which the latter is represented by a perfectly conducing wire and a cubic extension below the ground. The second one is the lightning channel configuration, which is represented by a vertical resistive wire coated by a fictitious material having a relative permittivity and a relative permeability values greater than that of the air. In the validation aim of the used approach and the developed calculating code, the simulation results are compared to those taken from the literature data recorded of the current waveforms at the top of the tower. According to this comparison, the approach proposed in this work yields reasonably accurate results. Thus, the effect of the variation of the ground conductivity values on the lightning current magnitudes and waveforms is examined. This investigation showed that the lightning current is affected by the variation of the ground conductivity values when it propagates along the tower and along the lightning channel.
{"title":"Analysis of Lightning Current Using Electromagnetic Models and 3D-FDTD Method in Presence of a Tall Object","authors":"M. Talbi, K. Arzag, Z. Azzouz","doi":"10.1109/ICLP56858.2022.9942509","DOIUrl":"https://doi.org/10.1109/ICLP56858.2022.9942509","url":null,"abstract":"In this work, we are interested in the study of the lightning return stroke current distribution along a tall object namely a tower and along the lightning channel. The considered tower is that of Peissenberg in Germany. To carry out this study, we have developed a computer code based on the use of electromagnetic models and the three dimensions finite difference time domain (3D-FDTD) method. The latter is combined to UMPL boundary conditions and is based on Taflove formulation. The program was developed in MATLAB environment. So, in this study electromagnetic models have two configurations. The first one is that adopted for the Peissenberg tower, in which the latter is represented by a perfectly conducing wire and a cubic extension below the ground. The second one is the lightning channel configuration, which is represented by a vertical resistive wire coated by a fictitious material having a relative permittivity and a relative permeability values greater than that of the air. In the validation aim of the used approach and the developed calculating code, the simulation results are compared to those taken from the literature data recorded of the current waveforms at the top of the tower. According to this comparison, the approach proposed in this work yields reasonably accurate results. Thus, the effect of the variation of the ground conductivity values on the lightning current magnitudes and waveforms is examined. This investigation showed that the lightning current is affected by the variation of the ground conductivity values when it propagates along the tower and along the lightning channel.","PeriodicalId":403323,"journal":{"name":"2022 36th International Conference on Lightning Protection (ICLP)","volume":"47 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-10-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130311987","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 : 2022-10-02DOI: 10.1109/ICLP56858.2022.9942468
S. Pack, J. Schröttner
Lightning strikes often pose a great risk to humans and their surroundings. Due to the numerous lightning strikes in Styria (province of Austria) individuals are occasionally struck directly or indirectly by lightning. The majority of the victims survived, however carrying away damages to health, varying in their severity. In the period from 2000 to 2017 22 lightning accidents with 55 lightning victims were reported by the local police department, four of the victims not surviving the impact or their consequences. The lightning accidents are analyzed according to several indications, such as daytime of the accident, age and gender of the victims, mechanisms of energy transmission to the human body, visible trails of the current path and amplitudes of the lightning current of the detected strokes, which were compared with data from the literature. The circumstances of the accidents, the effects of the lightning currents on the human body and the medical consequences were very different for all lightning stroke victims in Styria, but all injury patterns described as characteristic in the literature occurred. On average, two people per year were injured by direct or indirect lightning in this area. It could be shown that the amplitude of the lightning stroke is not crucial for the severity of the accidents or the survival of the victims.
{"title":"A 17 -year retrospective review of lightning victims in Austria with focus on lightning effects","authors":"S. Pack, J. Schröttner","doi":"10.1109/ICLP56858.2022.9942468","DOIUrl":"https://doi.org/10.1109/ICLP56858.2022.9942468","url":null,"abstract":"Lightning strikes often pose a great risk to humans and their surroundings. Due to the numerous lightning strikes in Styria (province of Austria) individuals are occasionally struck directly or indirectly by lightning. The majority of the victims survived, however carrying away damages to health, varying in their severity. In the period from 2000 to 2017 22 lightning accidents with 55 lightning victims were reported by the local police department, four of the victims not surviving the impact or their consequences. The lightning accidents are analyzed according to several indications, such as daytime of the accident, age and gender of the victims, mechanisms of energy transmission to the human body, visible trails of the current path and amplitudes of the lightning current of the detected strokes, which were compared with data from the literature. The circumstances of the accidents, the effects of the lightning currents on the human body and the medical consequences were very different for all lightning stroke victims in Styria, but all injury patterns described as characteristic in the literature occurred. On average, two people per year were injured by direct or indirect lightning in this area. It could be shown that the amplitude of the lightning stroke is not crucial for the severity of the accidents or the survival of the victims.","PeriodicalId":403323,"journal":{"name":"2022 36th International Conference on Lightning Protection (ICLP)","volume":"51 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-10-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133862246","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 : 2022-10-02DOI: 10.1109/ICLP56858.2022.9942483
N. Bacci, P. Randolph-Quinney, H. Hunt, K. Nixon, T. Augustine
Actualistic laboratory-based experimentation has shown that high impulse currents induce microtrauma to cadaveric bone, the patterns of which may have utility in lightning fatality determination However, it is unclear whether embalming solutions used to replace bodily $mathbf{fluids}$ and preserve the cadaveric tissues, may interfere with current transfer and induced-microtrauma patterns. As such, testing the resistance and impulse current passage of embalming fluids is crucial to build construct validity for biological studies. Low and high voltage impulse currents were applied to isotonic saline, used and fresh embalming solutions. Shunt voltage consistently increased across all solutions, despite embalming fluid having greater resistance to current flow. High voltage tests demonstrated fluid breakdown and current passage throughout all solutions. Current transfer results through embalming fluids suggest that high impulse currents are of sufficient magnitude to allow use of embalmed tissues in experimentation.
{"title":"Testing embalming solution suitability for high impulse current experimentation on biological tissue","authors":"N. Bacci, P. Randolph-Quinney, H. Hunt, K. Nixon, T. Augustine","doi":"10.1109/ICLP56858.2022.9942483","DOIUrl":"https://doi.org/10.1109/ICLP56858.2022.9942483","url":null,"abstract":"Actualistic laboratory-based experimentation has shown that high impulse currents induce microtrauma to cadaveric bone, the patterns of which may have utility in lightning fatality determination However, it is unclear whether embalming solutions used to replace bodily $mathbf{fluids}$ and preserve the cadaveric tissues, may interfere with current transfer and induced-microtrauma patterns. As such, testing the resistance and impulse current passage of embalming fluids is crucial to build construct validity for biological studies. Low and high voltage impulse currents were applied to isotonic saline, used and fresh embalming solutions. Shunt voltage consistently increased across all solutions, despite embalming fluid having greater resistance to current flow. High voltage tests demonstrated fluid breakdown and current passage throughout all solutions. Current transfer results through embalming fluids suggest that high impulse currents are of sufficient magnitude to allow use of embalmed tissues in experimentation.","PeriodicalId":403323,"journal":{"name":"2022 36th International Conference on Lightning Protection (ICLP)","volume":"67 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-10-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122994255","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 : 2022-10-02DOI: 10.1109/ICLP56858.2022.9942631
P. H. Pretorius
In protecting against lightning damage, specifically related to RS 485 industrial communication systems, the approach is typically to apply surge protective devices as mitigation measure. However, knowledge about the RS485 communication system dictates that a single point earth is required for its successful operation. Reverse operation of surge protective devices, applied downstream from the data acquisition unit, are likely to override the single point earthing system to introduce a multipoint earthing system, that can lead to exacerbated damage in large industrial plant, compared to before the installation of the surge protective devices. In this paper, the behaviour of a surge protective device applied to a typical industrial communication line, is assessed with support of numerical modelling to demonstrate the anticipated reverse operation of the protective device. This paper raises awareness about lightning ground potential rise and the application of surge protective devices, particularly in the case of wire-line technology, important to the lightning protection system designer.
{"title":"Reverse Operation of Surge Protective Devices on RS 485 Communication Lines Under Lightning Ground Potential Rise","authors":"P. H. Pretorius","doi":"10.1109/ICLP56858.2022.9942631","DOIUrl":"https://doi.org/10.1109/ICLP56858.2022.9942631","url":null,"abstract":"In protecting against lightning damage, specifically related to RS 485 industrial communication systems, the approach is typically to apply surge protective devices as mitigation measure. However, knowledge about the RS485 communication system dictates that a single point earth is required for its successful operation. Reverse operation of surge protective devices, applied downstream from the data acquisition unit, are likely to override the single point earthing system to introduce a multipoint earthing system, that can lead to exacerbated damage in large industrial plant, compared to before the installation of the surge protective devices. In this paper, the behaviour of a surge protective device applied to a typical industrial communication line, is assessed with support of numerical modelling to demonstrate the anticipated reverse operation of the protective device. This paper raises awareness about lightning ground potential rise and the application of surge protective devices, particularly in the case of wire-line technology, important to the lightning protection system designer.","PeriodicalId":403323,"journal":{"name":"2022 36th International Conference on Lightning Protection (ICLP)","volume":"53 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-10-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121346237","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}
京公网安备 11010802042870号
京ICP备2023020795号-1
扫码关注我们
求助内容：
应助结果提醒方式：