Pub Date : 2003-10-19DOI: 10.1109/CEIDP.2003.1254834
R. Altafim, C. Dias, L. G. Neto, H. C. Basso, C. Murakami, P. R. Veronese, É. F. Rodrigues
The development of new cellular and porous polymers has introduced new advances on the study of the piezoelectricity characteristics of electric charged polymers. Recently, a multi-layer space-charge electret was also fabricated using at least one "soft" porous and one "hard" nonporous Teflon PTFE film assembled in various multi-layer stacks. Now, in this paper we propose a new multi-layer space-charge electret fabricated using at least one Teflon-FEP film with small voids homogeneously distributed on its surface. The device has the same concept of the electret microphone mechanism. When these multi-layer setups are charged by impulse voltage process, it is possible to obtain samples with high piezoelectric coefficients. Controlling the size of the voids on the film interface, we can obtain a better control of the charging processes and, can determine a better value of the charging impulse voltage.
{"title":"Piezoelectricity of multi-layers space-charge electrets from Teflon FEP film with homogeneous voids distributed on its surface","authors":"R. Altafim, C. Dias, L. G. Neto, H. C. Basso, C. Murakami, P. R. Veronese, É. F. Rodrigues","doi":"10.1109/CEIDP.2003.1254834","DOIUrl":"https://doi.org/10.1109/CEIDP.2003.1254834","url":null,"abstract":"The development of new cellular and porous polymers has introduced new advances on the study of the piezoelectricity characteristics of electric charged polymers. Recently, a multi-layer space-charge electret was also fabricated using at least one \"soft\" porous and one \"hard\" nonporous Teflon PTFE film assembled in various multi-layer stacks. Now, in this paper we propose a new multi-layer space-charge electret fabricated using at least one Teflon-FEP film with small voids homogeneously distributed on its surface. The device has the same concept of the electret microphone mechanism. When these multi-layer setups are charged by impulse voltage process, it is possible to obtain samples with high piezoelectric coefficients. Controlling the size of the voids on the film interface, we can obtain a better control of the charging processes and, can determine a better value of the charging impulse voltage.","PeriodicalId":306575,"journal":{"name":"2003 Annual Report Conference on Electrical Insulation and Dielectric Phenomena","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2003-10-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131383582","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 : 2003-10-19DOI: 10.1109/CEIDP.2003.1254920
G. Montanari, M. Conti, F. Ciani, A. Cavallini, G. Mazzanti, S. Serra
An investigation on the behavior of partial discharges occurring in insulation cavities as a function of environmental conditions is presented in this paper. In particular, focus is made on peculiar conditions where semi-transparent insulation is subjected to different visible light intensity, is irradiated by UV or is kept in the dark. Experiments are carried out on cells with an artificial defect, obtained producing a spherical void in epoxy resin. It is shown that not only PD inception voltage is sensitive to fight wavelength and intensity, but also PD average delay time changes considerably. It can be speculated that inception voltage can be related prevailingly to either background radiation or field-assisted electron detrapping from defect surfaces, depending on defect geometry and environmental conditions.
{"title":"First electron availability and PD generation in insulation cavities","authors":"G. Montanari, M. Conti, F. Ciani, A. Cavallini, G. Mazzanti, S. Serra","doi":"10.1109/CEIDP.2003.1254920","DOIUrl":"https://doi.org/10.1109/CEIDP.2003.1254920","url":null,"abstract":"An investigation on the behavior of partial discharges occurring in insulation cavities as a function of environmental conditions is presented in this paper. In particular, focus is made on peculiar conditions where semi-transparent insulation is subjected to different visible light intensity, is irradiated by UV or is kept in the dark. Experiments are carried out on cells with an artificial defect, obtained producing a spherical void in epoxy resin. It is shown that not only PD inception voltage is sensitive to fight wavelength and intensity, but also PD average delay time changes considerably. It can be speculated that inception voltage can be related prevailingly to either background radiation or field-assisted electron detrapping from defect surfaces, depending on defect geometry and environmental conditions.","PeriodicalId":306575,"journal":{"name":"2003 Annual Report Conference on Electrical Insulation and Dielectric Phenomena","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2003-10-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131912473","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 : 2003-10-19DOI: 10.1109/CEIDP.2003.1254898
M. A. Hossain
Dielectric property of a liquid is depends upon different parameters such as temperature, frequency, impurities, moisture content and presence of other liquids etc. In this experiment Silicone fluids of different viscosity were used as the dielectric liquid and analar graded dimethyl ketone was used as the solvent and measurements were carried out at various mixture proportions, temperature and frequencies. The experimental values have been verified with the existing literature through the determination of the dipole moments, polarizability. Fourier Transform Infrared Spectroscopy (FTIR) analysis also performed for the verification of the liquid purity. Thus the measured results were employed to arrive at a unified method of calculating the dielectric properties.
{"title":"Dielectric properties of polar fluid mixtures at wide range of temperature and frequency","authors":"M. A. Hossain","doi":"10.1109/CEIDP.2003.1254898","DOIUrl":"https://doi.org/10.1109/CEIDP.2003.1254898","url":null,"abstract":"Dielectric property of a liquid is depends upon different parameters such as temperature, frequency, impurities, moisture content and presence of other liquids etc. In this experiment Silicone fluids of different viscosity were used as the dielectric liquid and analar graded dimethyl ketone was used as the solvent and measurements were carried out at various mixture proportions, temperature and frequencies. The experimental values have been verified with the existing literature through the determination of the dipole moments, polarizability. Fourier Transform Infrared Spectroscopy (FTIR) analysis also performed for the verification of the liquid purity. Thus the measured results were employed to arrive at a unified method of calculating the dielectric properties.","PeriodicalId":306575,"journal":{"name":"2003 Annual Report Conference on Electrical Insulation and Dielectric Phenomena","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2003-10-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128299465","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 : 2003-10-19DOI: 10.1109/CEIDP.2003.1254955
J. K. Nelson, Y. Hu, J. Thiticharoenpong
The incorporation of 38 nm titanium dioxide nanoparticles into an epoxy matrix to form a nanocomposite structure is described. The practical use of such materials has been evaluated through careful measurements of their electric strength made using recessed specimens as a function of particulate loading in comparison with an equivalent conventional resin formulated with micro-scale TiO/sub 2/ filler. The results would suggest that significant advantages accrue from the nano-formulated material in keeping with the known reduction in internal space charge accumulation earlier determined by pulse electroacoustic measurements. Furthermore, it is demonstrated that an optimum loading is indicated at about 10% (by weight). Based on additional thermally stimulated current and electroluminescence data, some suggestions are advanced which explain the improved performance in terms of the mitigating effects of trapped entanglement on the Maxwell-Wagner effect.
{"title":"Electrical properties of TiO/sub 2/ nanocomposites","authors":"J. K. Nelson, Y. Hu, J. Thiticharoenpong","doi":"10.1109/CEIDP.2003.1254955","DOIUrl":"https://doi.org/10.1109/CEIDP.2003.1254955","url":null,"abstract":"The incorporation of 38 nm titanium dioxide nanoparticles into an epoxy matrix to form a nanocomposite structure is described. The practical use of such materials has been evaluated through careful measurements of their electric strength made using recessed specimens as a function of particulate loading in comparison with an equivalent conventional resin formulated with micro-scale TiO/sub 2/ filler. The results would suggest that significant advantages accrue from the nano-formulated material in keeping with the known reduction in internal space charge accumulation earlier determined by pulse electroacoustic measurements. Furthermore, it is demonstrated that an optimum loading is indicated at about 10% (by weight). Based on additional thermally stimulated current and electroluminescence data, some suggestions are advanced which explain the improved performance in terms of the mitigating effects of trapped entanglement on the Maxwell-Wagner effect.","PeriodicalId":306575,"journal":{"name":"2003 Annual Report Conference on Electrical Insulation and Dielectric Phenomena","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2003-10-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"120887538","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 : 2003-10-19DOI: 10.1109/CEIDP.2003.1254811
M. Lessard, M. Masse
The evaluation of the state of the paper insulation of a power transformer can be assessed by the analysis of specific degradation by-products of paper such as CO, CO/sub 2/ and furanic compounds. However it is still difficult to differentiate an incipient fault from the normal aging of an equipment. There is a need to develop more precise diagnostic tools. An experimental accelerated aging test conducted on kraft paper and oil samples at 150/spl deg/C, allowed us to observe the production of new oil-soluble species. New compounds analogous to furanic derivatives were detected by high performance liquid chromatography. Specific sugars such as rhamnose and mannose were also detected by high performance ionic chromatography. The evolution of some of these species are correlated with the aging of the paper (decrease of the paper polymerization degree). Their presence in samples obtained from the field leads us to believe that selected molecules could play an important role in the prediction of remaining life of power transformers.
{"title":"Prediction of remaining life of the paper insulation by the analysis of new oil-soluble compounds in power transformers","authors":"M. Lessard, M. Masse","doi":"10.1109/CEIDP.2003.1254811","DOIUrl":"https://doi.org/10.1109/CEIDP.2003.1254811","url":null,"abstract":"The evaluation of the state of the paper insulation of a power transformer can be assessed by the analysis of specific degradation by-products of paper such as CO, CO/sub 2/ and furanic compounds. However it is still difficult to differentiate an incipient fault from the normal aging of an equipment. There is a need to develop more precise diagnostic tools. An experimental accelerated aging test conducted on kraft paper and oil samples at 150/spl deg/C, allowed us to observe the production of new oil-soluble species. New compounds analogous to furanic derivatives were detected by high performance liquid chromatography. Specific sugars such as rhamnose and mannose were also detected by high performance ionic chromatography. The evolution of some of these species are correlated with the aging of the paper (decrease of the paper polymerization degree). Their presence in samples obtained from the field leads us to believe that selected molecules could play an important role in the prediction of remaining life of power transformers.","PeriodicalId":306575,"journal":{"name":"2003 Annual Report Conference on Electrical Insulation and Dielectric Phenomena","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2003-10-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114893541","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 : 2003-10-19DOI: 10.1109/CEIDP.2003.1254863
T. Shioiri, J. Sato, T. Ozaki, O. Sakaguchi, T. Kamikawaji, M. Miyagawa, M. Homma, K. Suzuki
The authors have developed solid insulated switchgear that does not use SF/sub 6/ gas at all as an insulating medium. This paper describes the insulating material technology, diagnostic technology for partial discharge, insulation technology of the vacuum disconnecting switch and aerial composite insulation technology which are applied to this solid insulated switchgear. A new epoxy resin, which was dispersedly configured with spherical silica and rubber particles, was developed. The insulation performance of this resin is 50% higher compared with filling of alumina. Utilizing the features of the solid insulated switchgear, a diagnostic technology for partial discharge employing an acoustic emission (AE) sensor was developed. A vacuum disconnecting switch with high insulation reliability was developed applying Weibull distribution to dielectric breakdown in a vacuum. The insulated parts of insulating rods of circuit-breakers and disconnecting switches were miniaturized through composite insulation.
{"title":"Insulation technology for medium voltage solid insulated switchgear","authors":"T. Shioiri, J. Sato, T. Ozaki, O. Sakaguchi, T. Kamikawaji, M. Miyagawa, M. Homma, K. Suzuki","doi":"10.1109/CEIDP.2003.1254863","DOIUrl":"https://doi.org/10.1109/CEIDP.2003.1254863","url":null,"abstract":"The authors have developed solid insulated switchgear that does not use SF/sub 6/ gas at all as an insulating medium. This paper describes the insulating material technology, diagnostic technology for partial discharge, insulation technology of the vacuum disconnecting switch and aerial composite insulation technology which are applied to this solid insulated switchgear. A new epoxy resin, which was dispersedly configured with spherical silica and rubber particles, was developed. The insulation performance of this resin is 50% higher compared with filling of alumina. Utilizing the features of the solid insulated switchgear, a diagnostic technology for partial discharge employing an acoustic emission (AE) sensor was developed. A vacuum disconnecting switch with high insulation reliability was developed applying Weibull distribution to dielectric breakdown in a vacuum. The insulated parts of insulating rods of circuit-breakers and disconnecting switches were miniaturized through composite insulation.","PeriodicalId":306575,"journal":{"name":"2003 Annual Report Conference on Electrical Insulation and Dielectric Phenomena","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2003-10-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116211666","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 : 2003-10-19DOI: 10.1109/CEIDP.2003.1254877
R. Sarathi, S. Chandrasekar, C. Venkataseshaiah, N. Yoshimura
Tracking studies were carried out under AC and DC voltage, with EPDM specimens following IEC-587 standards. It is observed from the experimental study that the increase in conductivity, flow rate and the applied voltage reduces the tracking time of the material. In the present work, use of multi resolution signal decomposition technique and the artificial neural networks to monitor the surface condition of the insulation structure under AC voltage was demonstrated.
{"title":"Condition monitoring of outdoor polymeric insulation structures using wavelets and neural networks","authors":"R. Sarathi, S. Chandrasekar, C. Venkataseshaiah, N. Yoshimura","doi":"10.1109/CEIDP.2003.1254877","DOIUrl":"https://doi.org/10.1109/CEIDP.2003.1254877","url":null,"abstract":"Tracking studies were carried out under AC and DC voltage, with EPDM specimens following IEC-587 standards. It is observed from the experimental study that the increase in conductivity, flow rate and the applied voltage reduces the tracking time of the material. In the present work, use of multi resolution signal decomposition technique and the artificial neural networks to monitor the surface condition of the insulation structure under AC voltage was demonstrated.","PeriodicalId":306575,"journal":{"name":"2003 Annual Report Conference on Electrical Insulation and Dielectric Phenomena","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2003-10-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134420002","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 : 2003-10-19DOI: 10.1109/CEIDP.2003.1254820
É. David, N. Amyot, J. Drapeau
Dielectric Spectroscopy was used as a diagnostic tool to assess the degradation state of field-aged extruded cables retrieved from underground networks. A high voltage time-domain spectrometer was used to measure the time-domain dielectric response of unaged and field-aged cables up to 25 kV. In addition to time-domain dielectric spectroscopy (TDDS), high voltage frequency-domain dielectric spectroscopy (FDDS) was performed for the sake of comparison. Cables were characterized with respect to water content and water tree density. ACBD strength measurements were also performed on some of the cable samples in order to estimate their state of degradation. Field-aged and unaged cable accessories were also characterized with respect to their dielectric response in order to account for their effect on real line diagnostic.
{"title":"Diagnostic of field aged cables and accessories by time-domain dielectric spectroscopy","authors":"É. David, N. Amyot, J. Drapeau","doi":"10.1109/CEIDP.2003.1254820","DOIUrl":"https://doi.org/10.1109/CEIDP.2003.1254820","url":null,"abstract":"Dielectric Spectroscopy was used as a diagnostic tool to assess the degradation state of field-aged extruded cables retrieved from underground networks. A high voltage time-domain spectrometer was used to measure the time-domain dielectric response of unaged and field-aged cables up to 25 kV. In addition to time-domain dielectric spectroscopy (TDDS), high voltage frequency-domain dielectric spectroscopy (FDDS) was performed for the sake of comparison. Cables were characterized with respect to water content and water tree density. ACBD strength measurements were also performed on some of the cable samples in order to estimate their state of degradation. Field-aged and unaged cable accessories were also characterized with respect to their dielectric response in order to account for their effect on real line diagnostic.","PeriodicalId":306575,"journal":{"name":"2003 Annual Report Conference on Electrical Insulation and Dielectric Phenomena","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2003-10-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129393295","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 : 2003-10-19DOI: 10.1109/CEIDP.2003.1254884
R. Sundararajan, A. Mohammed, E. Soundarajan, J. Graves
Organic polymers, such as EPDM, by virtue of their very nature are susceptible to aging and degradation (weathering) when used for high voltage outdoor insulator applications. The very same flexible bonds that offer the advantages of polymers also make them vulnerable to aging and degradation. This paper presents the aging and degradation of 10 kV and 18 kV EP polymeric arresters removed after 10 years and 5 years of service respectively in Florida (FL). There is severe chalking and discoloration and alligatoring on the 10 year arrester. FTIR analysis showed major loss of various chemical groups, such as CH/sub 2/ and CH/sub 3/ above 95% in the alligatored part and up to 70% in the nonalligatored part. Similar but lesser magnitude changes were seen in the 5 year aged arrester. SEM micrographs of the field aged samples showed deeper cracks in alligatored portion compared to non-alligatored portion. Similar results, but of relatively lesser magnitude, were observed in the laboratory aging of arresters for a similar period.
{"title":"Field and lab aging of EP compound arresters","authors":"R. Sundararajan, A. Mohammed, E. Soundarajan, J. Graves","doi":"10.1109/CEIDP.2003.1254884","DOIUrl":"https://doi.org/10.1109/CEIDP.2003.1254884","url":null,"abstract":"Organic polymers, such as EPDM, by virtue of their very nature are susceptible to aging and degradation (weathering) when used for high voltage outdoor insulator applications. The very same flexible bonds that offer the advantages of polymers also make them vulnerable to aging and degradation. This paper presents the aging and degradation of 10 kV and 18 kV EP polymeric arresters removed after 10 years and 5 years of service respectively in Florida (FL). There is severe chalking and discoloration and alligatoring on the 10 year arrester. FTIR analysis showed major loss of various chemical groups, such as CH/sub 2/ and CH/sub 3/ above 95% in the alligatored part and up to 70% in the nonalligatored part. Similar but lesser magnitude changes were seen in the 5 year aged arrester. SEM micrographs of the field aged samples showed deeper cracks in alligatored portion compared to non-alligatored portion. Similar results, but of relatively lesser magnitude, were observed in the laboratory aging of arresters for a similar period.","PeriodicalId":306575,"journal":{"name":"2003 Annual Report Conference on Electrical Insulation and Dielectric Phenomena","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2003-10-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133796626","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 : 2003-10-19DOI: 10.1109/CEIDP.2003.1254816
J. Zhou, S. Mao, L.M. Wang, Z. Guan
This paper introduces the change of the characteristics of the surface state and electric performance of the composite insulator samples composed of different material, different process in production, and different colors after 31500 circle tests of tracking and erosion by the wheel test mode. In order to evaluate the change and the comparison of the samples, the test measures the leakage current and its involved characteristic values, hydrophobic state. And we also carry out the impulse power test to the samples after the test. The test appropriately simulates the influence of the weather with shower or with interval between rain and fine under atmospheric contamination on the composite insulator. The two kinds of the producing procedure, shed shaped by injection and vulcanization, and extrusion sheath and then, through the shed in the sheath. The test shows, though both of them has passed the 31500 circle tests, after the time the leakage current occurring and deposit dirtiness were statistic, we can find that the distribution of all the electricity and all dissipation energy passed the surface of the former is uniform, but that's of the latter is different.
{"title":"Circle tests of tracking and erosion of the composite insulator","authors":"J. Zhou, S. Mao, L.M. Wang, Z. Guan","doi":"10.1109/CEIDP.2003.1254816","DOIUrl":"https://doi.org/10.1109/CEIDP.2003.1254816","url":null,"abstract":"This paper introduces the change of the characteristics of the surface state and electric performance of the composite insulator samples composed of different material, different process in production, and different colors after 31500 circle tests of tracking and erosion by the wheel test mode. In order to evaluate the change and the comparison of the samples, the test measures the leakage current and its involved characteristic values, hydrophobic state. And we also carry out the impulse power test to the samples after the test. The test appropriately simulates the influence of the weather with shower or with interval between rain and fine under atmospheric contamination on the composite insulator. The two kinds of the producing procedure, shed shaped by injection and vulcanization, and extrusion sheath and then, through the shed in the sheath. The test shows, though both of them has passed the 31500 circle tests, after the time the leakage current occurring and deposit dirtiness were statistic, we can find that the distribution of all the electricity and all dissipation energy passed the surface of the former is uniform, but that's of the latter is different.","PeriodicalId":306575,"journal":{"name":"2003 Annual Report Conference on Electrical Insulation and Dielectric Phenomena","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2003-10-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133216469","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：