Pub Date : 2010-11-18DOI: 10.1109/ICHVE.2010.5640848
Z. Abdul-Malek, Z. Adzis, Sayuti Aulia, Yusoff Novizon, N. Abdullah
Lightning mapping or locating systems are based on several working principles such as the Time of Arrival (ToA) and the Directional Finder (DF). The country wide lightning locating system (LLS) owned by TNB Malaysia is able to determine the coordinate of the cloud-to-ground lightning strike within 500m accuracy. A new method is proposed to determine the coordinate of any cloud-to-ground lightning strike within a certain local region with a better accuracy. The localised LLS is based on the measurement of induced voltages due to lightning strikes in the vicinity of an existing overhead telephone lines. The localised lightning locating system (LLLS) is made up of three components: an overhead telephone line, a voltage surge measuring system, and a central processing station. The overhead telephone line was purposely constructed in such a way to simply form a Cartesian system suitable for lightning strike location mapping. The mapping of the lightning strike locations was successfully implemented using a Lab View based program. Simulated lightning as well as real lightning data were used in this study. The induced voltage waveforms were compared with other previously published data. The location calculations were compared with those obtained from the national LLS. Results show that the LLLS captures more lightning strikes during the period of the study.
{"title":"Waveform and location analyses of localised lightning locating system","authors":"Z. Abdul-Malek, Z. Adzis, Sayuti Aulia, Yusoff Novizon, N. Abdullah","doi":"10.1109/ICHVE.2010.5640848","DOIUrl":"https://doi.org/10.1109/ICHVE.2010.5640848","url":null,"abstract":"Lightning mapping or locating systems are based on several working principles such as the Time of Arrival (ToA) and the Directional Finder (DF). The country wide lightning locating system (LLS) owned by TNB Malaysia is able to determine the coordinate of the cloud-to-ground lightning strike within 500m accuracy. A new method is proposed to determine the coordinate of any cloud-to-ground lightning strike within a certain local region with a better accuracy. The localised LLS is based on the measurement of induced voltages due to lightning strikes in the vicinity of an existing overhead telephone lines. The localised lightning locating system (LLLS) is made up of three components: an overhead telephone line, a voltage surge measuring system, and a central processing station. The overhead telephone line was purposely constructed in such a way to simply form a Cartesian system suitable for lightning strike location mapping. The mapping of the lightning strike locations was successfully implemented using a Lab View based program. Simulated lightning as well as real lightning data were used in this study. The induced voltage waveforms were compared with other previously published data. The location calculations were compared with those obtained from the national LLS. Results show that the LLLS captures more lightning strikes during the period of the study.","PeriodicalId":287425,"journal":{"name":"2010 International Conference on High Voltage Engineering and Application","volume":"22 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-11-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116545331","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 : 2010-11-18DOI: 10.1109/ICHVE.2010.5640844
L. Cao, A. Zanwar, B. Pushpanathan, S. Grzybowski
Aging phenomenon of polymeric power cables have been extensively studied during last several decades. Despite the great achievement in single aging mechanism, much less was known about the aging phenomenon of cables under multi-stress conditions. This study focused on the electrical aging of 15 kV Ethylene Propylene Rubber (EPR) power cables aged by switching impulses superimposed with ac voltage in wet condition. The experiments aimed at better understanding of the electrical aging phenomenon of EPR cable insulation in wet condition. It also helped to assess the reliability of EPR cable used under such circumstances.
{"title":"Electrical aging of 15 kV EPR cable energized by AC voltage with switching impulses superimposed","authors":"L. Cao, A. Zanwar, B. Pushpanathan, S. Grzybowski","doi":"10.1109/ICHVE.2010.5640844","DOIUrl":"https://doi.org/10.1109/ICHVE.2010.5640844","url":null,"abstract":"Aging phenomenon of polymeric power cables have been extensively studied during last several decades. Despite the great achievement in single aging mechanism, much less was known about the aging phenomenon of cables under multi-stress conditions. This study focused on the electrical aging of 15 kV Ethylene Propylene Rubber (EPR) power cables aged by switching impulses superimposed with ac voltage in wet condition. The experiments aimed at better understanding of the electrical aging phenomenon of EPR cable insulation in wet condition. It also helped to assess the reliability of EPR cable used under such circumstances.","PeriodicalId":287425,"journal":{"name":"2010 International Conference on High Voltage Engineering and Application","volume":"18 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-11-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126128928","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 : 2010-11-18DOI: 10.1109/ICHVE.2010.5640859
R. Barnett, J. H. Nelson
This paper presents post event analyses of three inrush events that caused relay misoperation. It then presents the results of an EMTP study that illustrates the degree to which different techniques can mitigate the transformer inrush transient and compares this to the predicted performance of closing resistors in an identical application. It demonstrates that controlled switching of a transformer adequately mitigates inrush transients.
{"title":"Transformer inrush mitigation using controlled switching of a 500-kV circuit breaker","authors":"R. Barnett, J. H. Nelson","doi":"10.1109/ICHVE.2010.5640859","DOIUrl":"https://doi.org/10.1109/ICHVE.2010.5640859","url":null,"abstract":"This paper presents post event analyses of three inrush events that caused relay misoperation. It then presents the results of an EMTP study that illustrates the degree to which different techniques can mitigate the transformer inrush transient and compares this to the predicted performance of closing resistors in an identical application. It demonstrates that controlled switching of a transformer adequately mitigates inrush transients.","PeriodicalId":287425,"journal":{"name":"2010 International Conference on High Voltage Engineering and Application","volume":"433 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-11-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125759088","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 : 2010-11-18DOI: 10.1109/ICHVE.2010.5640861
S. Ang, Jinsheng Peng, Zhongdong Wang
In this paper, the parameters that caused the onset of fundamental (Period-1) ferroresonance upon a 400 kV transmission system are investigated. After validating the developed simulation model by comparing the ferroresonance field test records (voltage and current) with the simulation waveforms, network parameters in particular the capacitances of line are studied. The overall studies suggest that the circuit-to-circuit capacitors dominate the onset of the ferroresonance phenomena whereas the ground and line-to-line capacitors supply additional discharging currents to the core. The study was performed using a computer simulation package called ATPDraw.
{"title":"Identification of key circuit parameters for the initiation of ferroresonance in a 400-kV transmission system","authors":"S. Ang, Jinsheng Peng, Zhongdong Wang","doi":"10.1109/ICHVE.2010.5640861","DOIUrl":"https://doi.org/10.1109/ICHVE.2010.5640861","url":null,"abstract":"In this paper, the parameters that caused the onset of fundamental (Period-1) ferroresonance upon a 400 kV transmission system are investigated. After validating the developed simulation model by comparing the ferroresonance field test records (voltage and current) with the simulation waveforms, network parameters in particular the capacitances of line are studied. The overall studies suggest that the circuit-to-circuit capacitors dominate the onset of the ferroresonance phenomena whereas the ground and line-to-line capacitors supply additional discharging currents to the core. The study was performed using a computer simulation package called ATPDraw.","PeriodicalId":287425,"journal":{"name":"2010 International Conference on High Voltage Engineering and Application","volume":"9 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-11-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125854038","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 : 2010-11-18DOI: 10.1109/ICHVE.2010.5640749
T. Iwata, H. Okubo, H. Kojima, N. Hayakawa, F. Endo, Norihito Yanagita, T. Kato, T. Rokunohe
Discharge phenomena in a needle-plane electrode in air were studied with nano-second time resolution by means of synchronous measurement of streak image, light intensity, discharge current and fast-framing image. When positive impulse voltage was applied, a primary streamer initiated from the needle tip and propagated to the grounded plane electrode. A secondary streamer initiated after the primary streamer arrived at the plane electrode. There are close relations between the applied voltage, the primary and the secondary streamer current and the initiation time of the secondary streamer. The breakdown can start when the secondary streamer have arrived at the plane electrode. Moreover, the time to breakdown becomes shorter with the increase in the secondary streamer current.
{"title":"Positive streamer propagation and breakdown characteristics in non-uniform air gap","authors":"T. Iwata, H. Okubo, H. Kojima, N. Hayakawa, F. Endo, Norihito Yanagita, T. Kato, T. Rokunohe","doi":"10.1109/ICHVE.2010.5640749","DOIUrl":"https://doi.org/10.1109/ICHVE.2010.5640749","url":null,"abstract":"Discharge phenomena in a needle-plane electrode in air were studied with nano-second time resolution by means of synchronous measurement of streak image, light intensity, discharge current and fast-framing image. When positive impulse voltage was applied, a primary streamer initiated from the needle tip and propagated to the grounded plane electrode. A secondary streamer initiated after the primary streamer arrived at the plane electrode. There are close relations between the applied voltage, the primary and the secondary streamer current and the initiation time of the secondary streamer. The breakdown can start when the secondary streamer have arrived at the plane electrode. Moreover, the time to breakdown becomes shorter with the increase in the secondary streamer current.","PeriodicalId":287425,"journal":{"name":"2010 International Conference on High Voltage Engineering and Application","volume":"32 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-11-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125899565","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 : 2010-11-18DOI: 10.1109/ICHVE.2010.5640753
H. Martins, C. de Faria Ferreira, W. Cerqueira, Carlos Magno Vasques, M. Trindade
This work has its origin from research needed to identify possible damage in a short-circuit test transformer, during experiments for modeling secondary electrical arcs. In some cases the arc had self-extinguished applying a steep wave to the test circuit and its ac source (transformer). Aiming to investigate if there was any interaction between the suspect transformer and testing circuit and its excitations, a research was conducted in laboratory with controlled atmospheric impulse chopped waves, with typical “fall times” for discharges in air. An analysis considering the components of frequency generated by chopped in air, the amplifier factors generated by test circuit (short line + auxiliary transformer), the natural resonance frequencies of the suspect transformer and its frequency components of the BIL showed interesting coincidences that can be extrapolated to real power system conditions.
{"title":"Interaction between test circuit for generation of secondary arcs and short-circuit test transformer","authors":"H. Martins, C. de Faria Ferreira, W. Cerqueira, Carlos Magno Vasques, M. Trindade","doi":"10.1109/ICHVE.2010.5640753","DOIUrl":"https://doi.org/10.1109/ICHVE.2010.5640753","url":null,"abstract":"This work has its origin from research needed to identify possible damage in a short-circuit test transformer, during experiments for modeling secondary electrical arcs. In some cases the arc had self-extinguished applying a steep wave to the test circuit and its ac source (transformer). Aiming to investigate if there was any interaction between the suspect transformer and testing circuit and its excitations, a research was conducted in laboratory with controlled atmospheric impulse chopped waves, with typical “fall times” for discharges in air. An analysis considering the components of frequency generated by chopped in air, the amplifier factors generated by test circuit (short line + auxiliary transformer), the natural resonance frequencies of the suspect transformer and its frequency components of the BIL showed interesting coincidences that can be extrapolated to real power system conditions.","PeriodicalId":287425,"journal":{"name":"2010 International Conference on High Voltage Engineering and Application","volume":"129 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-11-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127387367","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 : 2010-11-18DOI: 10.1109/ICHVE.2010.5640723
A. Moukengue Imano, A. Beroual
This paper reports an experimental study of the deformation of water drops on both conducting and dielectric solid surfaces under ac voltage stress. The discharge activities between water drops and between a conducting water drop and a small rod electrode on a flat hydrophobic insulator are investigated. It's shown that the electric field applied to the drop surface is controlled by the electrode geometry and spacing between water drop and the electrode. The inception electric field strengths of partial discharges for rod electrode provide relevant inputs for the field inhomogeneity used in the simulation of the deformation of aligned water droplets. The discharge current characteristics of water drops on dielectric solid surface made of silicone rubber (SIR), under ac voltage stress are also measured. It's shown that the length of a discharge between droplets or between a single droplet and a small rod electrode is reduced through a particular type of its distortion. This is visually characterized by a water filament or thin film between the water drops along the insulator surface.
{"title":"Dynamics of water drops on metal and insulator surfaces submitted to AC voltage","authors":"A. Moukengue Imano, A. Beroual","doi":"10.1109/ICHVE.2010.5640723","DOIUrl":"https://doi.org/10.1109/ICHVE.2010.5640723","url":null,"abstract":"This paper reports an experimental study of the deformation of water drops on both conducting and dielectric solid surfaces under ac voltage stress. The discharge activities between water drops and between a conducting water drop and a small rod electrode on a flat hydrophobic insulator are investigated. It's shown that the electric field applied to the drop surface is controlled by the electrode geometry and spacing between water drop and the electrode. The inception electric field strengths of partial discharges for rod electrode provide relevant inputs for the field inhomogeneity used in the simulation of the deformation of aligned water droplets. The discharge current characteristics of water drops on dielectric solid surface made of silicone rubber (SIR), under ac voltage stress are also measured. It's shown that the length of a discharge between droplets or between a single droplet and a small rod electrode is reduced through a particular type of its distortion. This is visually characterized by a water filament or thin film between the water drops along the insulator surface.","PeriodicalId":287425,"journal":{"name":"2010 International Conference on High Voltage Engineering and Application","volume":"48 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-11-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132171970","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 : 2010-11-18DOI: 10.1109/ichve.2010.5640792
Randal Petty
Staged expansion of 500-kV GIS switchgear was completed at the Maury 500-kV Substation without impact to system performance based upon proper planning and execution of the work being performed.
{"title":"Maintaining regional reliability during expansion of the Maury 500-kV GIS facility","authors":"Randal Petty","doi":"10.1109/ichve.2010.5640792","DOIUrl":"https://doi.org/10.1109/ichve.2010.5640792","url":null,"abstract":"Staged expansion of 500-kV GIS switchgear was completed at the Maury 500-kV Substation without impact to system performance based upon proper planning and execution of the work being performed.","PeriodicalId":287425,"journal":{"name":"2010 International Conference on High Voltage Engineering and Application","volume":"22 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-11-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133491766","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 : 2010-11-18DOI: 10.1109/ICHVE.2010.5640831
D. Imamović, T. Kern, M. Muhr
As the historical development shows, both AC and DC transmission voltages have steadily increased. The growing demand for power supply induced the building of large power plants located far away from load centres. Also future projects in Europe such as DESERTEC or large offshore Wind Power Systems demand a smart solution of transmitting electric bulk power in an economic and efficient way over long distances. In order to reach this goal, very high voltages for transmission are necessary. AC-Voltages ≥1000 kV und DC-Voltages ≥±800 kV are defined as Ultra- High-Voltages (UHV). Based on the assumption of a continuous growth of energy demand, experts considered the invention of UHV transmission level in North America and Europe already 40 years ago [1]. However - it took almost 4 decades till the first UHV AC line reached operational status in China. This paper demonstrates possible ways of transmitting large bulk power generated in offshore wind parks over a distance of roughly 600 km (about 380 miles) across Germany. It contains and discusses the results of the investigation for all relevant characteristics, fragmented into general, mechanical, electrical and ecological parameters. After a detailed look on the mechanical construction of UHV overhead transmission lines it could be stated, that this was one of the limiting factors. Also the maximum power, which could be injected into one grid point is a critical value and has influenced the reliability analyses.
{"title":"System and technology comparison of UHV transmission concepts","authors":"D. Imamović, T. Kern, M. Muhr","doi":"10.1109/ICHVE.2010.5640831","DOIUrl":"https://doi.org/10.1109/ICHVE.2010.5640831","url":null,"abstract":"As the historical development shows, both AC and DC transmission voltages have steadily increased. The growing demand for power supply induced the building of large power plants located far away from load centres. Also future projects in Europe such as DESERTEC or large offshore Wind Power Systems demand a smart solution of transmitting electric bulk power in an economic and efficient way over long distances. In order to reach this goal, very high voltages for transmission are necessary. AC-Voltages ≥1000 kV und DC-Voltages ≥±800 kV are defined as Ultra- High-Voltages (UHV). Based on the assumption of a continuous growth of energy demand, experts considered the invention of UHV transmission level in North America and Europe already 40 years ago [1]. However - it took almost 4 decades till the first UHV AC line reached operational status in China. This paper demonstrates possible ways of transmitting large bulk power generated in offshore wind parks over a distance of roughly 600 km (about 380 miles) across Germany. It contains and discusses the results of the investigation for all relevant characteristics, fragmented into general, mechanical, electrical and ecological parameters. After a detailed look on the mechanical construction of UHV overhead transmission lines it could be stated, that this was one of the limiting factors. Also the maximum power, which could be injected into one grid point is a critical value and has influenced the reliability analyses.","PeriodicalId":287425,"journal":{"name":"2010 International Conference on High Voltage Engineering and Application","volume":"214 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-11-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134208871","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 : 2010-11-18DOI: 10.1109/ICHVE.2010.5640850
J. Rama Rao, J. Amarnath, S. Kamakshaiah
Very fast transient over voltages (VFTO) and very fast transient over currents (VFTC) are generated during switching operation of disconnectors in Gas insulated substation (GIS). In this paper the accurate GIS model has been developed and VFTO'S and VFTC'S were estimated at bushing termination using EMTP program. The wavelet analysis of VFTO and VFTC signals have been carried out and frequency spectrum of VFTO wave form is obtained. In order to estimate the frequency spectrum more accurate Gabor wavelet function is employed. By using above method the time-frequency spectrum of the VFTO waveform has been calculated at bushing termination in a 245kV GIS system during switching condition. The frequency characteristics of the VFTC have been analyzed using the Fast Fourier Transform (FFT) technique the validity of the wavelet function is confirmed by comparing both the results. This analysis helpful for an effective shielding of the control circuits present within the GIS against transient voltages and currents.
{"title":"Time-frequency analysis of very fast transient over voltages for effective shielding of control circuits in a 245kv gas Insulated Substation","authors":"J. Rama Rao, J. Amarnath, S. Kamakshaiah","doi":"10.1109/ICHVE.2010.5640850","DOIUrl":"https://doi.org/10.1109/ICHVE.2010.5640850","url":null,"abstract":"Very fast transient over voltages (VFTO) and very fast transient over currents (VFTC) are generated during switching operation of disconnectors in Gas insulated substation (GIS). In this paper the accurate GIS model has been developed and VFTO'S and VFTC'S were estimated at bushing termination using EMTP program. The wavelet analysis of VFTO and VFTC signals have been carried out and frequency spectrum of VFTO wave form is obtained. In order to estimate the frequency spectrum more accurate Gabor wavelet function is employed. By using above method the time-frequency spectrum of the VFTO waveform has been calculated at bushing termination in a 245kV GIS system during switching condition. The frequency characteristics of the VFTC have been analyzed using the Fast Fourier Transform (FFT) technique the validity of the wavelet function is confirmed by comparing both the results. This analysis helpful for an effective shielding of the control circuits present within the GIS against transient voltages and currents.","PeriodicalId":287425,"journal":{"name":"2010 International Conference on High Voltage Engineering and Application","volume":"423 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-11-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132582387","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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