2021 IEEE Electrical Insulation Conference (EIC)最新文献

Partial Discharge Inception Voltage in Liquid Dielectrics and its Definition 液体介质中局部放电起始电压及其定义

2021 IEEE Electrical Insulation Conference (EIC) Pub Date : 2021-06-07 DOI: 10.1109/eic49891.2021.9612307

L. Calcara, M. Pompili, M. Baur, J. Knauel

{"title":"Partial Discharge Inception Voltage in Liquid Dielectrics and its Definition","authors":"L. Calcara, M. Pompili, M. Baur, J. Knauel","doi":"10.1109/eic49891.2021.9612307","DOIUrl":"https://doi.org/10.1109/eic49891.2021.9612307","url":null,"abstract":"Insulating liquids represent the largest part of the insulating system in HV transformers and similar components; they are used for their excellent insulating and cooling performances and, for these reasons, they must also have high dielectric strength, high thermal conductivity and low viscosity. An important test able to give useful information on the properties of the same insulating liquids is the Partial Discharge Inception Voltage (PDIV) determination. PDIV measurement of liquid dielectrics is presently standardized by IEC TR 61294 (Determination of the partial discharge inception voltage - Test procedure), issued in 1993. This test is more sensitive than that used for the determination of the breakdown voltage (IEC 60156 or ASTM D1816 test methods) but requires a more complex experimental setup and, for this reason, it is less used. In IEC TR 61294 is also defined the Partial Discharge Inception Voltage (PDIV) as the lowest value at which at least only one partial discharge occurs of an apparent charge equal to or exceeding 100 pC, when the oil sample is tested under some specified conditions. This definition is slightly different from that given in the IEC 60270 (High-voltage test techniques - Partial discharge measurements) which reports that the PDIV is the applied voltage at which “repetitive partial discharges are first observed in the test object, when the voltage applied is gradually increased from a lower value at which no partial discharges are observed”. The present paper reports an experimental investigation for comparing PDIVs which may be found in different insulating liquids adopting different definitions, considering that in the nearest future the IEC TR 61294 will be revised and the ongoing project (WK65707) for preparing an ASTM Standard with the same scope.","PeriodicalId":298313,"journal":{"name":"2021 IEEE Electrical Insulation Conference (EIC)","volume":"46 40 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-06-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115305001","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

Potential distribution on stress grading system of coil end under operating temperature of rotating machines 旋转机械工作温度下线圈端应力分级系统的电位分布

2021 IEEE Electrical Insulation Conference (EIC) Pub Date : 2021-06-07 DOI: 10.1109/eic49891.2021.9612284

Yuki Hasegawa, A. Kumada, K. Hidaka, T. Okamoto, T. Umemoto

{"title":"Potential distribution on stress grading system of coil end under operating temperature of rotating machines","authors":"Yuki Hasegawa, A. Kumada, K. Hidaka, T. Okamoto, T. Umemoto","doi":"10.1109/eic49891.2021.9612284","DOIUrl":"https://doi.org/10.1109/eic49891.2021.9612284","url":null,"abstract":"Stator coil end of a rotating machine has a structure of electric field grading system (SG system) to relieve the high electric field. Although a rotating machine is operated at higher than $100^{circ}mathrm{C}$, the effect of temperature on SG system is not well understood. To investigate the performance of SG system under high temperature, experiments are conducted using a model bar simulating the end of a stator coil. AC 50 Hz voltage of 10kVp is applied to a virgin model bar at room temperature (RT) and then is heated up to $100^{circ}mathrm{C}$, and cooled to RT. This heating and cooling procedure is conducted for four times and potential distribution of the model bar at each stage was measured using a Pockels sensor. It was observed that the thermal history affects the electric field distribution formed on the SG system. The maximum value of the electric field strength on SG system, Emax, at RT gradually increased with the number heating cycle. On the other hand, the electric field strength at high temperature increased, but the effect of the thermal history was not as pronounced as at RT.","PeriodicalId":298313,"journal":{"name":"2021 IEEE Electrical Insulation Conference (EIC)","volume":"136 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-06-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114672353","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: 0

Design of a Pulse Generator for Testing Partial Discharge Measurement Systems 测试局部放电测量系统的脉冲发生器设计

2021 IEEE Electrical Insulation Conference (EIC) Pub Date : 2021-06-07 DOI: 10.1109/eic49891.2021.9612290

T. Hejtmánek, M. Judd, P. Drexler, B. Stewart

引用次数: 0

Numerical simulation of glow corona discharge in air based on a plasma chemical model 基于等离子体化学模型的空气辉光电晕放电数值模拟

2021 IEEE Electrical Insulation Conference (EIC) Pub Date : 2021-06-07 DOI: 10.1109/eic49891.2021.9612282

Mian Xiao, Hengxin He, Lipeng Liu, Bin Luo, Junru Che, Junjia He

{"title":"Numerical simulation of glow corona discharge in air based on a plasma chemical model","authors":"Mian Xiao, Hengxin He, Lipeng Liu, Bin Luo, Junru Che, Junjia He","doi":"10.1109/eic49891.2021.9612282","DOIUrl":"https://doi.org/10.1109/eic49891.2021.9612282","url":null,"abstract":"Glow corona is one of the major forms of positive DC corona discharge. In order to reveal the microscopic physical process of glow corona in air, a plasma chemical model of glow corona discharge in 1D coaxial wire was established based on COMSOL, considering 28 species and 127 chemical reactions (CKS, a comprehensive kinetic scheme), and the photoionization process. The temporal and spatial distribution and evolution of the major species during the glow corona discharge were obtained. The results show that the major positive ions in the gap are $mathbf{O}_{2} ^{+},$ which are distributed in a shell shape. Negative ions are O- $,mathbf{O}_{boldsymbol{2}} ^{-}$ and $mathbf{O}_{boldsymbol{3}} ^{-}$, which mainly exist in the ionization layer. $mathbf{O}^{-}$ and $mathbf{O}_{boldsymbol{2}} ^{-}$ participate in the detachment and provide seed electrons for the next pulse. The classical fluid model (FPM, a fully coupled physical model) fails to fully consider the detachment process of negative ions, resulting in the steepness and peak-to-peak value of current waves are too large. In order to accurately predict the current oscillation waveforms, in addition to $mathbf{O}_{boldsymbol{2}} ^{-}$, it is also necessary to consider $mathbf{O}^{-}$ in detachment process.","PeriodicalId":298313,"journal":{"name":"2021 IEEE Electrical Insulation Conference (EIC)","volume":"20 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-06-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127077284","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: 0

Defect diagnosis technology based on multi-spectral point cloud 基于多光谱点云的缺陷诊断技术

2021 IEEE Electrical Insulation Conference (EIC) Pub Date : 2021-06-07 DOI: 10.1109/eic49891.2021.9612269

Yang Yang, Ning Yang, Lihua Li, Fei Gao

引用次数: 0

Peroxide Decomposition Products in Factory Joints for DC XLPE Submarine Cable 直流交联聚乙烯海底电缆工厂接头中的过氧化物分解产物

2021 IEEE Electrical Insulation Conference (EIC) Pub Date : 2021-06-07 DOI: 10.1109/eic49891.2021.9612403

B. Sonerud, T. Mäkelä, J. Kjellqvist

引用次数: 0

Electrical Tree Progression in the Presence of Micro-voids due to Thermal Aging 由于热老化导致的微孔存在的电树进展

2021 IEEE Electrical Insulation Conference (EIC) Pub Date : 2021-06-07 DOI: 10.1109/eic49891.2021.9612342

Moon Moon Bordeori, N. Gupta

{"title":"Electrical Tree Progression in the Presence of Micro-voids due to Thermal Aging","authors":"Moon Moon Bordeori, N. Gupta","doi":"10.1109/eic49891.2021.9612342","DOIUrl":"https://doi.org/10.1109/eic49891.2021.9612342","url":null,"abstract":"Thermal aging irreversibly changes the chemical structure of the polymer, causing the formation of oxidized carbonaceous layers and micro-voids. Voids also increase in size and number due to thermal aging. The presence of voids is known to affect electric tree growth inside the epoxy resin. The current work aims to understand the effect of thermal aging on electrical tree growth using a stochastic 3D model. The numerical stochastic model is developed based on the Weismann and Zeller (WZ) model for electrical tree growth. Spherical voids of varying diameters are inserted into a computational sample. The tree is assumed to initiate from a needle tip of a needle-plane electrode configuration and grow in a step-wise manner from the existing tree structure. The location of a new branch is chosen stochastically, with the probability depending on the local electric field. After the addition of each tree branch, the electrical field is recalculated with appropriate boundary conditions. Partial discharges (PD) within the tree tubules result in charge redistribution along the channel walls and on the tips of tree tubules. Similarly, pd within existing voids cause charge deposition on the void walls. The effect of charge on tree tubules, tips, and void walls is taken into account in simulating tree progression. The effect of the size and distribution of the voids is investigated in this work. Computationally generated trees are compared with experimentally obtained trees.","PeriodicalId":298313,"journal":{"name":"2021 IEEE Electrical Insulation Conference (EIC)","volume":"40 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-06-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126331173","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

Application of Convolution Neural Network in Hydrophobicity Classification 卷积神经网络在疏水性分类中的应用

2021 IEEE Electrical Insulation Conference (EIC) Pub Date : 2021-06-07 DOI: 10.1109/eic49891.2021.9612318

Y. Fahmy, A. El-Hag

引用次数: 1

Power Capacity of High Voltage Cables for Future Electrical Aircraft 未来电动飞机用高压电缆的功率容量

2021 IEEE Electrical Insulation Conference (EIC) Pub Date : 2021-06-07 DOI: 10.1109/eic49891.2021.9612313

Hang Xu, R. Lowndes, I. Cotton

引用次数: 3

Oil flow damage in Kraft paper 1: Thermal aging 牛皮纸的油流损伤1:热老化

2021 IEEE Electrical Insulation Conference (EIC) Pub Date : 2021-06-07 DOI: 10.1109/eic49891.2021.9612325

I. Hosier, P. Lewin, G. Wilson

引用次数: 2