Pub Date : 1990-09-10DOI: 10.1109/ICDL.1990.202893
M. Lee, J. K. Nelson
Physical models which are representative of the materials, construction, and dimensions of power transformer duct structures have been fabricated for both core- and shell-form designs. Electrification characteristics have been documented as a function of the parameters of practical interest and the results obtained have the general character of those found in earlier studies. However, partial discharges have only been detected under worst-case conditions for the blocking structure associated with the shell-form configurations which generate more charge than the corresponding conditions in the core-form construction. The studies have quantified electrification in realistic models characteristic of actual transformers and could be used as a guide to provide estimates of charge levels in energized transformer structures.<>
{"title":"Flow-induced electrification and partial discharge measurements in energized transformer duct structures","authors":"M. Lee, J. K. Nelson","doi":"10.1109/ICDL.1990.202893","DOIUrl":"https://doi.org/10.1109/ICDL.1990.202893","url":null,"abstract":"Physical models which are representative of the materials, construction, and dimensions of power transformer duct structures have been fabricated for both core- and shell-form designs. Electrification characteristics have been documented as a function of the parameters of practical interest and the results obtained have the general character of those found in earlier studies. However, partial discharges have only been detected under worst-case conditions for the blocking structure associated with the shell-form configurations which generate more charge than the corresponding conditions in the core-form construction. The studies have quantified electrification in realistic models characteristic of actual transformers and could be used as a guide to provide estimates of charge levels in energized transformer structures.<<ETX>>","PeriodicalId":193137,"journal":{"name":"10th International Conference on Conduction and Breakdown in Dielectric Liquids","volume":"71 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1990-09-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121712038","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 : 1990-09-10DOI: 10.1109/ICDL.1990.202956
H. Borsi
The electric and dielectric behavior of ester fluid considered as a substitute for PCB is examined. After a short description of the insulating fluid, the authors consider the influence of temperature differences and aging condition of the insulation on the breakdown behavior of the fluid-paper combined dielectric. Furthermore, a comparison of the breakdown and aging behavior of cellulose-ester impregnated and aramid-ester impregnated insulating materials is given. Finally, the influence of partial discharge prestressing on the breakdown behavior of the fluid-paper combined dielectric is shown.<>
{"title":"Ester fluid Midel 7131 as PCB-substitute for distribution transformers","authors":"H. Borsi","doi":"10.1109/ICDL.1990.202956","DOIUrl":"https://doi.org/10.1109/ICDL.1990.202956","url":null,"abstract":"The electric and dielectric behavior of ester fluid considered as a substitute for PCB is examined. After a short description of the insulating fluid, the authors consider the influence of temperature differences and aging condition of the insulation on the breakdown behavior of the fluid-paper combined dielectric. Furthermore, a comparison of the breakdown and aging behavior of cellulose-ester impregnated and aramid-ester impregnated insulating materials is given. Finally, the influence of partial discharge prestressing on the breakdown behavior of the fluid-paper combined dielectric is shown.<<ETX>>","PeriodicalId":193137,"journal":{"name":"10th International Conference on Conduction and Breakdown in Dielectric Liquids","volume":"14 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1990-09-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123765887","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 : 1990-09-10DOI: 10.1109/ICDL.1990.202960
H. Borsi, U. Schroder
The authors report on investigations performed to determine the relationship between PD parameters and the dissolved gas generated by partial discharges in mineral-based oil. The PD activity of mineral-based oil is shown to depend upon many parameters, including the influence of the standing time between the filling of the test vessel and the switching of the test voltage as well as the voltage's magnitude on the PD activity. Regarding the gassing behavior, several hydrocarbons show a linear (increasing) dependence upon the integral PD parameters. By contrast the amount of oxygen decreases with increasing PD loading. Calculation of gas ratios indicates that the relation between hydrogen and methane is a sensitive indicator of PD activity in mineral-based oil.<>
{"title":"The correlation between partial discharges (PD) and gassing in insulating liquids","authors":"H. Borsi, U. Schroder","doi":"10.1109/ICDL.1990.202960","DOIUrl":"https://doi.org/10.1109/ICDL.1990.202960","url":null,"abstract":"The authors report on investigations performed to determine the relationship between PD parameters and the dissolved gas generated by partial discharges in mineral-based oil. The PD activity of mineral-based oil is shown to depend upon many parameters, including the influence of the standing time between the filling of the test vessel and the switching of the test voltage as well as the voltage's magnitude on the PD activity. Regarding the gassing behavior, several hydrocarbons show a linear (increasing) dependence upon the integral PD parameters. By contrast the amount of oxygen decreases with increasing PD loading. Calculation of gas ratios indicates that the relation between hydrogen and methane is a sensitive indicator of PD activity in mineral-based oil.<<ETX>>","PeriodicalId":193137,"journal":{"name":"10th International Conference on Conduction and Breakdown in Dielectric Liquids","volume":"10 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1990-09-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125634886","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 : 1990-09-10DOI: 10.1109/ICDL.1990.202910
M. Bologa, I.A. Kozhukhar, A. Malakhov, I. Kozhevnikov
Theoretical and experimental results on single-stage and multistage electrohydrodynamic pumps are discussed. Investigations of their head-delivery characteristics, efficiency, and service life depending on the geometric parameters of the pump, field, and working liquid parameters are examined.<>
{"title":"Electrodynamic transport of liquid","authors":"M. Bologa, I.A. Kozhukhar, A. Malakhov, I. Kozhevnikov","doi":"10.1109/ICDL.1990.202910","DOIUrl":"https://doi.org/10.1109/ICDL.1990.202910","url":null,"abstract":"Theoretical and experimental results on single-stage and multistage electrohydrodynamic pumps are discussed. Investigations of their head-delivery characteristics, efficiency, and service life depending on the geometric parameters of the pump, field, and working liquid parameters are examined.<<ETX>>","PeriodicalId":193137,"journal":{"name":"10th International Conference on Conduction and Breakdown in Dielectric Liquids","volume":"16 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1990-09-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121758066","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 : 1990-09-10DOI: 10.1109/ICDL.1990.202972
I. M. Gavrilov, V. R. Kukhta, V. Lopatin
Prebreakdown events in a nonuniform field in water were studied experimentally. Branching dendrites propagating with subsonic velocities and thin supersonic plasma channels were observed to form. It was found that, in deionized water, heating has no effect on the initiation and development of discharge channels. It is further shown that the EHD (electrohydrodynamic) events for discharge times of 10/sup -4/ to 10/sup -3/ affect the development of slow dendrites without changing the discharge dynamics.<>
{"title":"The effect of heating and EHD events on breakdown in water","authors":"I. M. Gavrilov, V. R. Kukhta, V. Lopatin","doi":"10.1109/ICDL.1990.202972","DOIUrl":"https://doi.org/10.1109/ICDL.1990.202972","url":null,"abstract":"Prebreakdown events in a nonuniform field in water were studied experimentally. Branching dendrites propagating with subsonic velocities and thin supersonic plasma channels were observed to form. It was found that, in deionized water, heating has no effect on the initiation and development of discharge channels. It is further shown that the EHD (electrohydrodynamic) events for discharge times of 10/sup -4/ to 10/sup -3/ affect the development of slow dendrites without changing the discharge dynamics.<<ETX>>","PeriodicalId":193137,"journal":{"name":"10th International Conference on Conduction and Breakdown in Dielectric Liquids","volume":"23 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1990-09-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134080772","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 : 1990-09-10DOI: 10.1109/ICDL.1990.202945
J. Muller, J. Abendroth, K. Barner
The stability of suspensions of ferroelectric (BaTiO/sub 3/) nm-particles, using heptane as carrier liquid and oleic acid as stabilizer, is investigated by means of electrooptic Kerr rotation and optical transmittance. On suspension up to 0.006 solid volume fraction, with permanent dipole moments existing at 5 nm>
{"title":"Stability of suspensions of ferroelectric BaTiO/sub 3/ particles in hydrocarbon carrier liquids","authors":"J. Muller, J. Abendroth, K. Barner","doi":"10.1109/ICDL.1990.202945","DOIUrl":"https://doi.org/10.1109/ICDL.1990.202945","url":null,"abstract":"The stability of suspensions of ferroelectric (BaTiO/sub 3/) nm-particles, using heptane as carrier liquid and oleic acid as stabilizer, is investigated by means of electrooptic Kerr rotation and optical transmittance. On suspension up to 0.006 solid volume fraction, with permanent dipole moments existing at 5 nm<r<20 nm (14 mC/cm/sup 2/ at 20 nm), 10-90% reversible changes in the transmittance were observed while the Kerr rotation was apparently unaffected. This can be explained by a field-induced reversible agglomeration of about 5% of the particles. Irreversible agglomeration is also observed for high solid volume fractions and low stabilizer content.<<ETX>>","PeriodicalId":193137,"journal":{"name":"10th International Conference on Conduction and Breakdown in Dielectric Liquids","volume":"111 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1990-09-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124699337","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 : 1990-09-10DOI: 10.1109/ICDL.1990.202872
A. Gonidec
Summary form only given. Ionization chambers filled with liquefied noble gas have been commonly used as particle detectors. Recent research on warm liquids has made possible the construction of a large-scale calorimeter at CERN, filled with tetramethylpentane. For continuously sensitive detectors used in cosmic-ray physics, ultrahigh purity of the liquid is required to allow the electrons to travel over large distances without being trapped by impurities. Electron lifetimes of a few milliseconds have been reached in cryogenic liquids, and lifetimes of a few hundred microseconds have been obtained in warm liquids to assure good performance of the calorimeter.<>
{"title":"Liquid ionization detectors: the UA-1 collaboration","authors":"A. Gonidec","doi":"10.1109/ICDL.1990.202872","DOIUrl":"https://doi.org/10.1109/ICDL.1990.202872","url":null,"abstract":"Summary form only given. Ionization chambers filled with liquefied noble gas have been commonly used as particle detectors. Recent research on warm liquids has made possible the construction of a large-scale calorimeter at CERN, filled with tetramethylpentane. For continuously sensitive detectors used in cosmic-ray physics, ultrahigh purity of the liquid is required to allow the electrons to travel over large distances without being trapped by impurities. Electron lifetimes of a few milliseconds have been reached in cryogenic liquids, and lifetimes of a few hundred microseconds have been obtained in warm liquids to assure good performance of the calorimeter.<<ETX>>","PeriodicalId":193137,"journal":{"name":"10th International Conference on Conduction and Breakdown in Dielectric Liquids","volume":"21 3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1990-09-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125888077","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 : 1990-09-10DOI: 10.1109/ICDL.1990.202954
Z. Yu
A new anti-ageing additive for improving the electrical properties and preventing the degradation of liquid dielectrics in power capacitors is introduced. When it is added in the right proportion, the partial discharge property of an all-film power capacitor impregnated by the liquid dielectric will be ameliorated and service life will be longer.<>
{"title":"A new additive for improving the electrical property of liquid dielectric in power capacitor","authors":"Z. Yu","doi":"10.1109/ICDL.1990.202954","DOIUrl":"https://doi.org/10.1109/ICDL.1990.202954","url":null,"abstract":"A new anti-ageing additive for improving the electrical properties and preventing the degradation of liquid dielectrics in power capacitors is introduced. When it is added in the right proportion, the partial discharge property of an all-film power capacitor impregnated by the liquid dielectric will be ameliorated and service life will be longer.<<ETX>>","PeriodicalId":193137,"journal":{"name":"10th International Conference on Conduction and Breakdown in Dielectric Liquids","volume":"140 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1990-09-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122413395","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 : 1990-09-10DOI: 10.1109/ICDL.1990.202908
F. Pontiga, A. Castellanos
The effect of residual conductivity on the stability of a horizontal dielectric liquid layer subjected to a weak unipolar injection and buoyancy is analyzed. Cases of heating from below and from above have been considered. Regions of steady and oscillatory instability are delineated by direct integration of the electrothermohydrodynamic equations for the case of constant mobility and permittivity.<>
{"title":"The effect of residual conduction on weak unipolar injection and buoyancy driven instabilities","authors":"F. Pontiga, A. Castellanos","doi":"10.1109/ICDL.1990.202908","DOIUrl":"https://doi.org/10.1109/ICDL.1990.202908","url":null,"abstract":"The effect of residual conductivity on the stability of a horizontal dielectric liquid layer subjected to a weak unipolar injection and buoyancy is analyzed. Cases of heating from below and from above have been considered. Regions of steady and oscillatory instability are delineated by direct integration of the electrothermohydrodynamic equations for the case of constant mobility and permittivity.<<ETX>>","PeriodicalId":193137,"journal":{"name":"10th International Conference on Conduction and Breakdown in Dielectric Liquids","volume":"33 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1990-09-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126559361","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 : 1990-09-10DOI: 10.1109/ICDL.1990.202947
H. Sato, Y. Nonaka, T. Takada
The electric field distribution profile in transformer insulating oil as a function of time after application of DC step voltage and change of the DC voltage polarity was measured using a highly sensitive advanced Kerr electrooptic technique. The lower limit of the applied electric field intensity was 100 V/cm in insulating oil with an electrode length of 8 cm. Charge distribution as a function of time was calculated from the measured electric field distribution. Mobilities of positive and negative ionic carriers, 0.025 and 0.030 cm/sup 2//Vs, respectively, were determined from the relationship between the saturation time of charge density and applied DC voltage. The relaxation time of accumulated charge near the electrodes after short-circuiting the electrodes was independent of the preapplied DC voltage.<>
{"title":"Electric field distribution in transformer oil containing an additive using the Kerr-effect technique under various DC stress conditions","authors":"H. Sato, Y. Nonaka, T. Takada","doi":"10.1109/ICDL.1990.202947","DOIUrl":"https://doi.org/10.1109/ICDL.1990.202947","url":null,"abstract":"The electric field distribution profile in transformer insulating oil as a function of time after application of DC step voltage and change of the DC voltage polarity was measured using a highly sensitive advanced Kerr electrooptic technique. The lower limit of the applied electric field intensity was 100 V/cm in insulating oil with an electrode length of 8 cm. Charge distribution as a function of time was calculated from the measured electric field distribution. Mobilities of positive and negative ionic carriers, 0.025 and 0.030 cm/sup 2//Vs, respectively, were determined from the relationship between the saturation time of charge density and applied DC voltage. The relaxation time of accumulated charge near the electrodes after short-circuiting the electrodes was independent of the preapplied DC voltage.<<ETX>>","PeriodicalId":193137,"journal":{"name":"10th International Conference on Conduction and Breakdown in Dielectric Liquids","volume":"28 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1990-09-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126993817","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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