2015 IEEE Conference on Electrical Insulation and Dielectric Phenomena (CEIDP)最新文献_第7页

AC partial discharge characteristic at minute air gap under non-uniform electric field 非均匀电场作用下小气隙交流局部放电特性

2015 IEEE Conference on Electrical Insulation and Dielectric Phenomena (CEIDP) Pub Date : 2015-12-17 DOI: 10.1109/CEIDP.2015.7352078

M. Kida, T. Kawashima, Y. Murakami, M. Nagao

{"title":"AC partial discharge characteristic at minute air gap under non-uniform electric field","authors":"M. Kida, T. Kawashima, Y. Murakami, M. Nagao","doi":"10.1109/CEIDP.2015.7352078","DOIUrl":"https://doi.org/10.1109/CEIDP.2015.7352078","url":null,"abstract":"For a raise of the miniaturization and reliability of various electric power apparatuses, it is important to clarify the partial discharge characteristic in their insulation part. In many case, partial discharge may occur under the non-uniform field. So, it is necessary to understand the partial discharge characteristic under non-uniform electric filed. Partial discharge inception voltage (PDIV) was measured under AC voltage application using needle-plane electrode system. Partial discharge inception electric field (PDIE) was estimated using COMSOL that is a general purpose physical simulation software. When the air gap distance was below 50 μm and the tip radius was 10, 30 and 60 μm, PDIE at the needle tip was almost the same as the electric field estimated by the Paschen curve. In this case, it is considered that PDIV may be decided by the electric field at the needle tip and that the emission of initial electrons plays very important role in the partial discharge process. However, when the needle tip radius was 10 or 30 μm and the air gap distance became 50 μm, PDIE at the needle tip became higher than the electric field strength estimated by the Paschen curve. In this latter case, it is considered that even if initial electron was emitted from the needle tip, the electric field was not enough to develop the detectable electron avalanche. From our experiment, the electric field strength necessary to the detectable partial discharge development is estimated to be about 67 % of the electric field strength necessary to the initial electron emission from the needle tip.","PeriodicalId":432404,"journal":{"name":"2015 IEEE Conference on Electrical Insulation and Dielectric Phenomena (CEIDP)","volume":"26 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-12-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122436752","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}

引用次数: 1

Introducing free volume in strongly dipolar polymers to achieve high dielectric constant 在强偶极聚合物中引入自由体积以获得高介电常数

2015 IEEE Conference on Electrical Insulation and Dielectric Phenomena (CEIDP) Pub Date : 2015-12-17 DOI: 10.1109/CEIDP.2015.7352046

Yash Thakur, Minren Lin, Shan Wu, Q. Zhang

{"title":"Introducing free volume in strongly dipolar polymers to achieve high dielectric constant","authors":"Yash Thakur, Minren Lin, Shan Wu, Q. Zhang","doi":"10.1109/CEIDP.2015.7352046","DOIUrl":"https://doi.org/10.1109/CEIDP.2015.7352046","url":null,"abstract":"Advances in modern electronics require the development of polymer-based dielectric materials with high dielectric constant, low dielectric loss, and high thermal stability. Fundamental dielectric theory suggests that strongly dipolar polymers have the potential to realize a high dielectric constant. In order to achieve high thermal stability, these polymers should also possess a high glass transition temperature Tg. However, it has been observed in many dielectric polymers that the dielectric constant decreases markedly at temperatures below Tg due to dipole freezing. This study shows that a high energy density polymer with low loss and high operating temperature can be realized in a family of weakly-coupled strongly-dipolar polymers, such as aromatic urea and thiourea. Our experimental results uncover that disorder (or blending) in these polymers leads to a significantly larger free volume at temperatures far below Tg, thereby enabling easier reorientation of dipoles in response to an electric field. The net result is a substantial enhancement in the dielectric constant while preserving low dielectric loss and very high breakdown field. The results here pave the way for creating high energy density polymers with low loss and high operating temperature.","PeriodicalId":432404,"journal":{"name":"2015 IEEE Conference on Electrical Insulation and Dielectric Phenomena (CEIDP)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-12-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124929692","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}

引用次数: 3

Mixed Weibull distribution model of DC dielectric breakdowns with dual defect modes 双缺陷模式直流介质击穿的混合威布尔分布模型

2015 IEEE Conference on Electrical Insulation and Dielectric Phenomena (CEIDP) Pub Date : 2015-12-17 DOI: 10.1109/CEIDP.2015.7352017

A. Andersen, J. Dennison

{"title":"Mixed Weibull distribution model of DC dielectric breakdowns with dual defect modes","authors":"A. Andersen, J. Dennison","doi":"10.1109/CEIDP.2015.7352017","DOIUrl":"https://doi.org/10.1109/CEIDP.2015.7352017","url":null,"abstract":"This work provides physical insight into common statistical models for DC dielectric breakdown field strengths. Voltage step-up tests were performed on low density polyethylene films. The merits of generalizations to widely-used empirical Weibull models are discussed. The cumulative probability distributions of the breakdown fields were fit to standard two- and three-parameter Weibull distributions. Mixed two-parameter Weibull distributions, sometimes used in the literature to model multiple breakdown modes, were found to yield the best fits to the data. In addition, the same data were fit to a physically-motivated dual-defect mean field model incorporating both low- and high-energy defect modes with different defect densities; this produced a much better fit than single-defect mean field models. Values obtained for the mean defect energies and densities were within the ranges expected from independent determinations of these intrinsic materials properties. By incorporating these physics-based concepts into traditionally empirical models, their accuracy and utility can be extended. The mixed Weibull distribution and the dual-defect model predicted very similar cumulative distributions of LDPE breakdown data, suggesting that mixed Weibull distributions may reflect similar multiple defect modes used in dual-defect models. Theories of DC breakdown, based on distributions of microscopic defects in disordered insulating materials may provide improved guidance in understanding the physical origins of empirical parameters used in statistical methods to characterize breakdown properties.","PeriodicalId":432404,"journal":{"name":"2015 IEEE Conference on Electrical Insulation and Dielectric Phenomena (CEIDP)","volume":"28 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-12-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128743715","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}

引用次数: 19

Influence of surface contamination of conductor on positive corona-generated audible noise spectrum characteristics of HVDC system 导体表面污染对高压直流系统正电晕可听噪声频谱特性的影响

2015 IEEE Conference on Electrical Insulation and Dielectric Phenomena (CEIDP) Pub Date : 2015-12-17 DOI: 10.1109/CEIDP.2015.7351996

Yong Yi, Chuyan Zhang, Yuanjiu Wang, Zhengying Chen, Liming Wang

{"title":"Influence of surface contamination of conductor on positive corona-generated audible noise spectrum characteristics of HVDC system","authors":"Yong Yi, Chuyan Zhang, Yuanjiu Wang, Zhengying Chen, Liming Wang","doi":"10.1109/CEIDP.2015.7351996","DOIUrl":"https://doi.org/10.1109/CEIDP.2015.7351996","url":null,"abstract":"Surface contamination of high-voltage direct-current power transmission lines has a large influence on corona characteristics. The audible noise of the polluted conductors is much higher than clean conductors. Little is known about the effect of the surface conditions of conductors on spectrum characteristics of the positive corona-generated audible noise under a high voltage. In order to investigate the influence of surface contamination produced by atmospheric pollution on the spectrum of the audible noise, this paper presented the measurement of spectrum characteristics of the audible noise of positive corona discharge in a laboratory corona cage. We researched the influence of deposition and relative permittivity of the contamination on the spectrum characteristics of the positive corona-generated audible noise. The relationships among these factors were consequently acquired. The results revealed that the spectral components of the audible noise of clean conductor were obviously different with the increase of the applied voltage. The spectral components (>1kHz) of the polluted conductors were much higher than those of the clean conductors. The contamination adhering to the surface of conductors affected spectral components (>1kHz) much more obviously than low spectral components, and the results were analyzed in this paper. The conclusion lays a foundation for researching the influence of the surface conditions on the corona-generated audible noise.","PeriodicalId":432404,"journal":{"name":"2015 IEEE Conference on Electrical Insulation and Dielectric Phenomena (CEIDP)","volume":"24 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-12-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128389585","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}

引用次数: 2

Effect of nanoparticles on space charge behavior of XLPE/SiC nanocomposites 纳米颗粒对XLPE/SiC纳米复合材料空间电荷行为的影响

2015 IEEE Conference on Electrical Insulation and Dielectric Phenomena (CEIDP) Pub Date : 2015-12-17 DOI: 10.1109/CEIDP.2015.7352033

Youyuan Wang, C. Wang

引用次数: 4

Terahertz and far-infrared spectroscopic estimation of vinyl acetate content in ethylene-vinyl acetate copolymer 乙烯-醋酸乙烯共聚物中乙酸乙烯含量的太赫兹和远红外光谱估计

2015 IEEE Conference on Electrical Insulation and Dielectric Phenomena (CEIDP) Pub Date : 2015-12-17 DOI: 10.1109/CEIDP.2015.7351988

Tomoyuki Izutsu, D. Odaka, M. Komatsu, Y. Ohki, M. Mizuno, Yoshiaki Nakamura, Naofumi Chiwata

引用次数: 1

Thermal and dielectric properties evaluation of low density polyethylene - Boron Nitride - Carbon Black nanocomposites 低密度聚乙烯-氮化硼-炭黑纳米复合材料的热学和介电性能评价

2015 IEEE Conference on Electrical Insulation and Dielectric Phenomena (CEIDP) Pub Date : 2015-12-17 DOI: 10.1109/CEIDP.2015.7352150

H. Couderc, M. Frechette, É. David

{"title":"Thermal and dielectric properties evaluation of low density polyethylene - Boron Nitride - Carbon Black nanocomposites","authors":"H. Couderc, M. Frechette, É. David","doi":"10.1109/CEIDP.2015.7352150","DOIUrl":"https://doi.org/10.1109/CEIDP.2015.7352150","url":null,"abstract":"Preparation of nanocomposites with several nanofillers is a promising way to tailor the physical properties of materials. In this work, Boron Nitride and Carbon Black were chosen as additives. Both are thermally conductive but Boron Nitride is an electric insulator where Carbon Black is conductive. The allying of their properties should produce materials with high thermal conductivity and tailored electrical conductivity. Crystallinity rate, normalized to the LDPE content, and melting temperature remained unchanged at 33 wt% and 105°C respectively. The BDS measurements exhibited a tremendous increase of both real and imaginary parts of the permittivity above 4 wt% of CB (more than 8 orders of magnitude), translating into a sharp increase of conductivity as the percolation threshold of CB is reached. Thermo Gravimetric, Dielectric Breakdown Strength and Thermal Conductivity measurements were also conducted to complete this study. As a conclusion, allying hBN and CB nanoparticles lead to a promising way to tailor both the permittivity and the conductivities of LDPE-based composites.","PeriodicalId":432404,"journal":{"name":"2015 IEEE Conference on Electrical Insulation and Dielectric Phenomena (CEIDP)","volume":"70 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-12-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129875154","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}

引用次数: 2

Effects of soluble constituents on insulator flashover performance and flashover voltage prediction 可溶性成分对绝缘子闪络性能及闪络电压预测的影响

2015 IEEE Conference on Electrical Insulation and Dielectric Phenomena (CEIDP) Pub Date : 2015-12-17 DOI: 10.1109/CEIDP.2015.7352057

Dongdong Zhang, Zhijin Zhang, Yang Zhongyi, Liu Youchao, Xingliang Jiang

{"title":"Effects of soluble constituents on insulator flashover performance and flashover voltage prediction","authors":"Dongdong Zhang, Zhijin Zhang, Yang Zhongyi, Liu Youchao, Xingliang Jiang","doi":"10.1109/CEIDP.2015.7352057","DOIUrl":"https://doi.org/10.1109/CEIDP.2015.7352057","url":null,"abstract":"Pollution materials affect insulator flashover performance, and there is long-term significance in researching it. In this paper, common kinds of nitrates were used as the soluble pollution, and the ac flashover tests of typical glass insulator were carried out. During the tests, the samples were polluted by dipping method. Also, up-and-down method was used to obtain the insulator flashover gradients under different pollutants and ESDD values. Basing on the test data, the effects of nitrates on insulator flashover performance were analyzed. Research results indicate that, using the current method to calculate the flashover gradient of insulator polluted with nitrates, the relative error will reach 24%; Flashover gradient of insulator under nitrates is higher than that under NaCl; KNO3 corresponds to lower flashover gradient while Ca(NO3)2 corresponds to a higher one; The pollution characteristic b of glass insulator under nitrates is within 0.18 - 0.25; The flashover gradient EL of glass insulator polluted by single or mixed nitrate can be expressed by 25.6×ESDD-0.21.","PeriodicalId":432404,"journal":{"name":"2015 IEEE Conference on Electrical Insulation and Dielectric Phenomena (CEIDP)","volume":"8 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-12-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125499812","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}

引用次数: 3

Aging effect on oil cooling capacity of a non-guided disc windings power transformer 老化对非导向圆盘绕组电力变压器油冷却能力的影响

2015 IEEE Conference on Electrical Insulation and Dielectric Phenomena (CEIDP) Pub Date : 2015-12-17 DOI: 10.1109/CEIDP.2015.7352049

K. S. Kassi, I. Fofana, M. Farinas, C. Volat

引用次数: 5

Pre-breakdown arcing as proxy for DC dielectric breakdown testing of polymeric insulators 预击穿电弧法在聚合物绝缘子直流介质击穿试验中的应用

2015 IEEE Conference on Electrical Insulation and Dielectric Phenomena (CEIDP) Pub Date : 2015-12-17 DOI: 10.1109/CEIDP.2015.7352084

A. Andersen, J. Dennison

引用次数: 8