2011 Annual Report Conference on Electrical Insulation and Dielectric Phenomena最新文献

Diagnosis of cable aging by broadband impedance spectroscopy 宽带阻抗谱法诊断电缆老化

2011 Annual Report Conference on Electrical Insulation and Dielectric Phenomena Pub Date : 2011-12-01 DOI: 10.1109/CEIDP.2011.6232587

Y. Ohki, T. Yamada, N. Hirai

{"title":"Diagnosis of cable aging by broadband impedance spectroscopy","authors":"Y. Ohki, T. Yamada, N. Hirai","doi":"10.1109/CEIDP.2011.6232587","DOIUrl":"https://doi.org/10.1109/CEIDP.2011.6232587","url":null,"abstract":"Since electric wires and cables play very important roles of supplying electric power and transmitting information and control signals, their degradation may cause a serious problem. In the present research, we examined the applicability of the broadband impedance spectroscopy (BIS) to monitor the degradation of cable insulation. The BIS method is to measure the magnitude and phase angle of impedance as a function of frequency in a very wide frequency range. First, cables were aged partially by heat and γ-rays. Further, a hole was drilled from the outer to inner conductors in some cables, and was filled with a NaCl solution in order to simulate a vented water tree. The difference in magnitude or phase angle of impedance before and after the aging becomes clearer by fast Fourier transform analyses, regardless of whether the aging was given by the γ-rays or water trees. The location of the degradation was also possible without referring to the data before the aging. These results clearly indicate that the BIS method has a potential ability to locate the degradation of cable insulation induced by various kinds of damages.","PeriodicalId":6317,"journal":{"name":"2011 Annual Report Conference on Electrical Insulation and Dielectric Phenomena","volume":"31 1","pages":"24-27"},"PeriodicalIF":0.0,"publicationDate":"2011-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91312287","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: 25

Comparison of the effects of nanofiller materials on the dielectric properties of epoxy nanocomposites 纳米填充材料对环氧纳米复合材料介电性能影响的比较

2011 Annual Report Conference on Electrical Insulation and Dielectric Phenomena Pub Date : 2011-12-01 DOI: 10.1109/CEIDP.2011.6232660

J. Katayama, N. Fuse, M. Kozako, T. Tanaka, Y. Ohki

{"title":"Comparison of the effects of nanofiller materials on the dielectric properties of epoxy nanocomposites","authors":"J. Katayama, N. Fuse, M. Kozako, T. Tanaka, Y. Ohki","doi":"10.1109/CEIDP.2011.6232660","DOIUrl":"https://doi.org/10.1109/CEIDP.2011.6232660","url":null,"abstract":"Composites of organic polymers and well-dispersed nm-sized inorganic fillers, called polymer nanocomposites (NCs), have been attracting much attention as new electrical insulating materials. In this paper, experimental results on the typical dielectric properties, namely, complex permittivity (εr' and εr\"), conductivity, and thermally stimulated depolarization current (TSDC) are evaluated for bisphenol-A epoxy resin and its NCs with boehmite alumina, titania, and silica. The increase in εr' and εr\" and the magnitudes of the TSDC peaks as well as the increase in conductivity appear more significantly in the NCs with boehmite alumina and titania and less significantly in the NCs with silica than in epoxy resin. This indicates that the silica nanofillers give the best results as far as these properties are concerned. The suppression of molecular motion by the addition of nanofillers seems to work effectively in the case of silica, while the nanofiller addition is likely to accelerate the motion of ionic carriers and/or that of dipoles in the case of boehmite alumina and titania.","PeriodicalId":6317,"journal":{"name":"2011 Annual Report Conference on Electrical Insulation and Dielectric Phenomena","volume":"100 1","pages":"318-321"},"PeriodicalIF":0.0,"publicationDate":"2011-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82399046","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: 4

Feasibility study on the detection of corrosion of a cable metal shield using terahertz imaging 太赫兹成像检测电缆金属屏蔽腐蚀的可行性研究

2011 Annual Report Conference on Electrical Insulation and Dielectric Phenomena Pub Date : 2011-12-01 DOI: 10.1109/CEIDP.2011.6232599

R. Sato, M. Komatsu, M. Mizuno, K. Fukunaga, Y. Ohki

{"title":"Feasibility study on the detection of corrosion of a cable metal shield using terahertz imaging","authors":"R. Sato, M. Komatsu, M. Mizuno, K. Fukunaga, Y. Ohki","doi":"10.1109/CEIDP.2011.6232599","DOIUrl":"https://doi.org/10.1109/CEIDP.2011.6232599","url":null,"abstract":"Time-domain imaging and spectroscopic measurements were carried out using terahertz (THz) light in order to examine the feasibility of non-destructive corrosion diagnosis of a metallic shielding layer in a power cable. At first, the absorbance of the THz light was measured for various corroded copper, namely copper oxide, basic copper carbonate, and copper chloride. As a result, both basic copper carbonate and copper chloride were found to exhibit absorption clear and strong enough for the imaging. Next, a non-corroded copper plate and one of the corroded plates were placed on a metal plate without making an open interspace, and the THz light was irradiated and scanned in order to get two-dimensional images. When the plate is corroded to form either basic copper carbonate or copper chloride, the intensity of reflected light becomes small compared with the non-corroded copper plate. The reason for this seems that the THz light was scattered more at the surface of the corroded copper plate and was absorbed more by the corrosion. These phenomena indicate that non-destructive diagnosis to detect corrosion of a shield metal is possible.","PeriodicalId":6317,"journal":{"name":"2011 Annual Report Conference on Electrical Insulation and Dielectric Phenomena","volume":"158 1","pages":"72-75"},"PeriodicalIF":0.0,"publicationDate":"2011-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80008801","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

Influence of A.C. electric field on plant growth 交流电场对植物生长的影响

2011 Annual Report Conference on Electrical Insulation and Dielectric Phenomena Pub Date : 2011-12-01 DOI: 10.1109/CEIDP.2011.6232626

S. Iwata, T. Okumura, Y. Muramoto, N. Shimizu

引用次数: 4

Optimum D.C. electric field strength for growth acceleration of thale cress 加速芥蓝生长的最佳直流电场强度

2011 Annual Report Conference on Electrical Insulation and Dielectric Phenomena Pub Date : 2011-12-01 DOI: 10.1109/CEIDP.2011.6232623

T. Okumura, S. Iwata, Y. Muramoto, N. Shimizu

{"title":"Optimum D.C. electric field strength for growth acceleration of thale cress","authors":"T. Okumura, S. Iwata, Y. Muramoto, N. Shimizu","doi":"10.1109/CEIDP.2011.6232623","DOIUrl":"https://doi.org/10.1109/CEIDP.2011.6232623","url":null,"abstract":"We have studied the influence of D.C. electric field on plant growth. Raphanus sativus longipinnatus (daikon radish) and Arabidopsis thaliana (thale cress) were used as sample. Thale cress is widely used as one of the model organisms for studying plant sciences, because its genome has been already sequenced. In the previous paper, we had reported the following results for daikon radish: (a) The application of D.C. electric field improves the seed germination rate. (b) The D.C. electric field increases the length and the weight. (c) The D.C. electric field encourages the consumption of substances which is stored in the seed. The following results had been also reported for thale cress: (d) The D.C. electric field accelerates the seed germination. (e) The D.C. electric field exerts no effect on seed germination when the electric potential of the thale cress is grounded. It is expected that there is an optimum strength of D.C. electric field for plant growth acceleration. As the first step to seek the optimum strength, we adopted 2.5kV/m and 10.0kV/m. Namely, the seeds of thale cress were cultivated under D.C. electric field of 2.5kV/m and 10.0kV/m. As a result, the growth of the sample was more promoted by 10.0kV/m D.C. field than by 2.5kV/m D.C. field.","PeriodicalId":6317,"journal":{"name":"2011 Annual Report Conference on Electrical Insulation and Dielectric Phenomena","volume":"85 1","pages":"168-171"},"PeriodicalIF":0.0,"publicationDate":"2011-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78179408","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

Recognition of partial discharges using an Ensemble of Neural Networks 基于神经网络集成的局部放电识别

2011 Annual Report Conference on Electrical Insulation and Dielectric Phenomena Pub Date : 2011-10-19 DOI: 10.1109/CEIDP.2011.6232703

A. Mas’ud, B. Stewart, S. McMeekin, A. Nesbitt

{"title":"Recognition of partial discharges using an Ensemble of Neural Networks","authors":"A. Mas’ud, B. Stewart, S. McMeekin, A. Nesbitt","doi":"10.1109/CEIDP.2011.6232703","DOIUrl":"https://doi.org/10.1109/CEIDP.2011.6232703","url":null,"abstract":"This paper introduces an improved method for classifying Partial Discharge (PD) patterns using Ensemble Neural Network (ENN) learning. The method is based on training several Neural Network (NN) models and combining their predictions. In this paper it is applied to the recognition of PD from artificially created poly-ethylene-terephthalate (PET) voids and in particular the ability of the ENN to categorise statistical Φ-q-n patterns for two different void sizes over 50 and 250 power cycles. The training data for the ENN comprises statistical parameters obtained from voids of 0.6mm and 1mm diameter. Measurements were made on three separately manufactured void samples for both these diameters. Similarities between the different PD measurements and different cycle captures is investigated using both a Single Neural Network (SNN) and the ENN. For each set of 3 void samples, each NN was trained and tested from the data of one PD void defect. Each NN was then tested using data from two other void geometries in order to determine the recognition abilities of both the ENN and SNN. The results show that the ENN always produces higher recognition efficiency for unseen data when compared to the SNN. It is also shown that ENN produces similar recognition predictions for PD patterns captured using either 50 or 250 power cycles while the SNN shows more sensitivity to the number of power cycles captured.","PeriodicalId":6317,"journal":{"name":"2011 Annual Report Conference on Electrical Insulation and Dielectric Phenomena","volume":"28 1","pages":"497-500"},"PeriodicalIF":0.0,"publicationDate":"2011-10-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80946336","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: 9

Stoichiometry and effects of nano-sized and micro-sized fillers on an epoxy based system 环氧基体系中纳米级和微级填料的化学计量学及影响

2011 Annual Report Conference on Electrical Insulation and Dielectric Phenomena Pub Date : 2011-10-16 DOI: 10.1109/CEIDP.2011.6232656

V. Nguyen, A. Vaughan, P. Lewin, A. Krivda

引用次数: 6

Space charge behavior in polyethylene under AC electric fields 交流电场作用下聚乙烯的空间电荷行为

2011 Annual Report Conference on Electrical Insulation and Dielectric Phenomena Pub Date : 2011-10-16 DOI: 10.1109/CEIDP.2011.6232607

J. Zhao, Z. Xu, G. Chen, P. Lewin

{"title":"Space charge behavior in polyethylene under AC electric fields","authors":"J. Zhao, Z. Xu, G. Chen, P. Lewin","doi":"10.1109/CEIDP.2011.6232607","DOIUrl":"https://doi.org/10.1109/CEIDP.2011.6232607","url":null,"abstract":"Polyethylene has been widely used as the insulation of high voltage power cables due to its excellent dielectric properties and electrical performance. The existence of space charge in polymeric insulators is a significant issue with respect to life expectation. It can alter the local electric field and initiate possible partial discharge or eventual breakdown. This appears relatively more severe under dc applied fields than in the ac case. Research results have been extensively reported about space charge in polymers under dc electric stress. In contrast, space charge behavior under ac stress has not been fully examined or understood. However, the improvements in material processing and manufacturing have led to these materials being used under high ac electric fields. The effect of space charge under ac conditions can be an issue affecting the electrical performance of the material and needs to be carefully examined. At Southampton, a fast pulsed electro-acoustic (PEA) system equipped with 2 kHz HV pulse generator has been developed in order to acquire the fast dynamics of space charge in polyethylene under ac voltages. Space charge in low density polyethylene under ac voltages of 0.1 Hz to 50 Hz has been measured and detailed results are discussed in the paper.","PeriodicalId":6317,"journal":{"name":"2011 Annual Report Conference on Electrical Insulation and Dielectric Phenomena","volume":"37 1","pages":"105-108"},"PeriodicalIF":0.0,"publicationDate":"2011-10-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82188800","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: 8

Measurement of partial discharge activities within two artificial spherical voids in an epoxy resin 环氧树脂中两个人造球形空隙内局部放电活度的测量

2011 Annual Report Conference on Electrical Insulation and Dielectric Phenomena Pub Date : 2011-10-16 DOI: 10.1109/CEIDP.2011.6232701

H. Illias, G. Chen, P. Lewin

引用次数: 5

Multisource PD identification based on phase synchronous and asynchronous data 基于相位同步和异步数据的多源PD识别

2011 Annual Report Conference on Electrical Insulation and Dielectric Phenomena Pub Date : 2011-10-16 DOI: 10.1109/CEIDP.2011.6232694

D. Evagorou, A. Kyprianou, G. Georghiou, L. Hao, P. Lewin, A. Stavrou

{"title":"Multisource PD identification based on phase synchronous and asynchronous data","authors":"D. Evagorou, A. Kyprianou, G. Georghiou, L. Hao, P. Lewin, A. Stavrou","doi":"10.1109/CEIDP.2011.6232694","DOIUrl":"https://doi.org/10.1109/CEIDP.2011.6232694","url":null,"abstract":"Partial Discharge (PD) measurements in cables and their accessories play a fundamental role in Condition Based Monitoring (CBM) of High Voltage (HV) equipment. CBM monitoring has been enforced by utilities in the transmission and distribution (T&D) environment as part of a predictive maintenance program that aims to result in less unscheduled downtime and lower maintenance cost. Identifying the source of a PD rather than merely assessing its magnitude provides additional information that could enable more educated decisions concerning the integrity of the insulation to be made. In on-line scenarios the presence of multiple PD sources that are simultaneously active as well as the presence of interference, complicates the identification process. In this paper, the Density-Based Spatial Clustering of Applications with Noise (DBSCAN) algorithm has been employed to identify PDs of different sources. Phase synchronous measurements were acquired in the laboratory and pre-processed through a peak detection algorithm to extract the single pulses (phase asynchronous). To extract a feature the Wavelet Packet Transform (WPT) and Higher Order Statistics (HOS) were employed according to previous work by the authors. The feature was then analyzed by the Principal Component Analysis (PCA) for dimensionality reduction and study of different PD sources has been shown to form separate clusters. Application of this method on on-line data acquired from the network of the Electricity Authority of Cyprus (EAC) has demonstrated its potential use in PD identification and interference rejection.","PeriodicalId":6317,"journal":{"name":"2011 Annual Report Conference on Electrical Insulation and Dielectric Phenomena","volume":"70 1","pages":"460-463"},"PeriodicalIF":0.0,"publicationDate":"2011-10-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79728052","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