2007 Electrical Insulation Conference and Electrical Manufacturing Expo最新文献

{"title":"Defining safe operating voltages for aerospace electrical systems","authors":"I. Cotton, A. Nelms, M. Husband","doi":"10.1109/EEIC.2007.4562590","DOIUrl":"https://doi.org/10.1109/EEIC.2007.4562590","url":null,"abstract":"Increased electrical power demands are being experienced on the new generation of aircraft due to an increased reliance on electrical technology such as air conditioning, de-icing systems and electrical flight control actuation. Sustaining the transmission of hundreds of kilowatts of electrical power at low voltages, typical around 115 V, is not feasible owing to the penalties incurred due to high cable weights and issues relating to voltage drop. The use of higher voltages would reduce system weight but comes with a penalty in the increased likelihood of electrical discharge within the power system. This paper details studies of systems used to transmit power in aircraft. The studies examine the voltages at which systems could be used without the existence of partial discharge. This is done from a theoretical standpoint but is based on the results of tests of typical insulation systems. These tests have been carried out in an environmental chamber that can simulate an aircraft at altitude. It is shown that an increase to ever higher voltages does not lead to a continuous reduction in the power transfer to weight ratio of cabling systems. The optimum voltage is shown to depend on a number of factors.","PeriodicalId":152045,"journal":{"name":"2007 Electrical Insulation Conference and Electrical Manufacturing Expo","volume":"5 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117114680","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}

{"title":"UHF and IEC60270 correlation analysis of radiated frequency band measurements on resin insulation void samples","authors":"B. Stewart, A. Reid, M. Judd, R. Fouracre","doi":"10.1109/EEIC.2007.4562605","DOIUrl":"https://doi.org/10.1109/EEIC.2007.4562605","url":null,"abstract":"Partial discharge (PD) measurement is an established condition monitoring technique used to assess the deterioration of high voltage insulation systems such as power transformers and gas-insulated switchgear. Two popular monitoring techniques employ radiated RF measurements and conventional apparent charge measurements according to the IEC60270 Standard. Recent research has shown that combining simultaneous radiated RF with IEC60270 measurements of PD events appears to provide additional information to assist in the discrimination of specific insulation faults. This paper aims to show for sample voids in resin that the frequency content of the radiated RF signals can be used as an additional discriminatory feature for simultaneous RF and IEC60270 measurements in identifying PD produced by single and multiple resin voids under electrical stress.","PeriodicalId":152045,"journal":{"name":"2007 Electrical Insulation Conference and Electrical Manufacturing Expo","volume":"74 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127373338","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}

{"title":"Application of flat glass backed mica paper tape to VPI’ed high voltage stator coils","authors":"F. Emery, M. Williams","doi":"10.1109/EEIC.2007.4562580","DOIUrl":"https://doi.org/10.1109/EEIC.2007.4562580","url":null,"abstract":"The trend to boost MVA capabilities with smaller machine size of large electrical generators, has concentrated on the reduction of stator coil groundwall insulation thickness to obtain a better heat flow to maintain efficiency. This approach has about reached its limits using the presently commercially available glass backed mica tapes on VPI'ed stator coils. The major limitation that has been reached is the dielectric performance of the groundwall. To improve the dielectrics, one approach initiated by a leading tape manufacturer is to fabricate a glass backed mica tape using a thinner carrier or glass backing. This thinner glass is more commonly referred to as flat glass which describes its physical makeup. A number of papers have described and compared this new flat glass mica paper tape with mica tape that uses a standard glass carrier for backing. The advantage of using the flat glass is that a higher density of mica paper can fit into the space allocated for the high voltage coil groundwall insulation. In this way, the dielectrics can be increased and by using an overall thinner groundwall thickness, enhanced thermal performance can be realized. Significant improvement in void reduction is also realized because of the reduction in free space between tape layers. However, with this reduction in free space, paths for the resin impregnation are also reduced. There are many significant challenges associated with the practical application of the flat glass mica tape to the insulation of high voltage stator coils when using a VPI process. Fabrication and testing of both test bars and full size stator coils, impregnated with an epoxy resin, have resulted in many significant differences when compared to the use of conventional glass backed mica tape. Excellent electrical performance can be realized when applying the flat glass mica paper tape provided manufacturing adjustments are incorporated. This paper will present the findings of extensive testing of test bars and full size stator coils, insulated with the flat glass mica tape and VPI'ed with an Epoxy resin.","PeriodicalId":152045,"journal":{"name":"2007 Electrical Insulation Conference and Electrical Manufacturing Expo","volume":"192 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125851478","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}

{"title":"Experimental evaluation of the effect of humidification on the performaance of PEM fuel cell stack","authors":"J. Huson, P.C. Lundherg, R. Herry, A. Bourgeau, A. Snyder, S. Das, E. Ubong","doi":"10.1109/EEIC.2007.4562653","DOIUrl":"https://doi.org/10.1109/EEIC.2007.4562653","url":null,"abstract":"Humidification of proton exchange membrane fuel cells (PEMFC) is needed to prevent the electrolyte from drying out, and prevents the flow of protons through the electrolyte and membranes. Humidifying either electrodes or both is expected to affect the performance enhancement of these cells. In order to establish this effect, an experimental study is conducted on a four-cell stack with an active cell area of 140 cm2 and a built-in, membrane humidifier on the cathode side to analyze how humidifying just the cathode side of the stack varies from humidifying both the cathode and anode sides. A multi-station test bench and a humidification bottle are used to evaluate how varying the humidification on both electrodes affects the performance of the stack. Tests are conducted at various loads and a constant dew-point temperature first without the humidification bottle on the anode side, and then with the bottle to evaluate how humidification of both electrodes affects the fuel cell stack. Various polarization curves are established from the experimental data, and the relationship between different dew-point temperatures and humidifying both electrodes is determined graphically. The effect of varying current densities and corresponding voltages is also investigated from the experimental data.","PeriodicalId":152045,"journal":{"name":"2007 Electrical Insulation Conference and Electrical Manufacturing Expo","volume":"43 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126751985","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}

{"title":"Overview of nanodielectrics: Insulating materials of the future","authors":"J. K. Nelson","doi":"10.1109/EEIC.2007.4562626","DOIUrl":"https://doi.org/10.1109/EEIC.2007.4562626","url":null,"abstract":"Several research groups worldwide have now been able to document some significant improvements that can be made in the electrical, and other, properties of polymer composites through the incorporation of nanoparticulates. Although it is now becoming clear that the mechanisms responsible for these changes are by no means universal, some of the benefits are substantial and rely on the large interface areas which are inherent in the introduction of materials of nanometric dimensions. By examining a variety of nanomaterials, this contribution seeks to review the property changes that can be brought about and examines the possibilities for commercial applications. This involves not only the electrical properties, but the implications for the attendant mechanical characteristics and the polymer processing necessary for utilization of this emerging breed of dielectric material. In this context, the functionalization of the particulate surfaces to provide preferential coupling to the host polymer will be explored since, by this means, a degree of preferred assembly can be accommodated. Through experimental examples, the use of this technique to tailor the properties of nanodielectrics is illustrated.","PeriodicalId":152045,"journal":{"name":"2007 Electrical Insulation Conference and Electrical Manufacturing Expo","volume":"6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114949853","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}

{"title":"Partial discharge pulse shape detection and analysis under DC condition","authors":"Xiaohua Li, Guangning Wu, Xueqin Zhang, Shanshan Bian","doi":"10.1109/EEIC.2007.4562586","DOIUrl":"https://doi.org/10.1109/EEIC.2007.4562586","url":null,"abstract":"With high voltage DC apparatus widely applied nowadays, partial discharge (PD) in these apparatus at DC voltage occurred frequently. However, PD under DC condition is not well understood yet. Therefore, there is an interest in investigating the character of PD under DC conditions. In this paper PD under DC condition is obtained in internal discharge models, surface discharge models and corona discharge models. The discharge pulse shapes and PD characteristics under DC condition in three kinds of typical defect models are compared. The PD characteristics under different stages of DC condition in three lands of typical defect models are analyzed.","PeriodicalId":152045,"journal":{"name":"2007 Electrical Insulation Conference and Electrical Manufacturing Expo","volume":"24 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115107449","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}

{"title":"Effect of temperature and thermal expansion on slot partial discharge activity","authors":"C. Hudon, M. Chaaban, M. Bélec, D. Nguyen","doi":"10.1109/EEIC.2007.4562602","DOIUrl":"https://doi.org/10.1109/EEIC.2007.4562602","url":null,"abstract":"The influence of generator load changes on partial discharge (PD) activity can be significant especially when the semi-conductive coating of stator bars is eroded. It is common knowledge that thermal expansion (copper, core and insulation) will decrease the gap size in the slot between the bar and the core and this could lead to a reduction of slot PD activity. In the present study, a surface defect was made on a stator bar and a variable gap between the bare insulation surface and a ground plane was adjusted from close contact to fixed gaps of 0.25, 0.5 and 1.0 mm. Partial discharge measurements were recorded at different temperatures for each of these four gap sizes. The stator bar was both electrically stressed at 8.0 kV and thermally stressed by a circulating current. For each gap dimension, PD tests were carried out at room temperature (22degC), and with circulating current at 53,70,90 and 132degC. By comparing results from different gaps at a fixed temperature and results from different temperatures at a fixed gap, it was possible to determine which one of these two parameters had the greatest influence on the PD signals. The effect of these changes with respect to gap size was compared with an evaluation of the thermal expansion of a bar in its slot under normal operating conditions. This study leads to a better understanding of the change expected in slot PD activity with load variations when measurements will be performed on actual generators.","PeriodicalId":152045,"journal":{"name":"2007 Electrical Insulation Conference and Electrical Manufacturing Expo","volume":"62 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114533701","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}

{"title":"Energy saving potential and characteristics of motors for consumer applications","authors":"A. Kulatunga, E. Persson, R. Sundararajan","doi":"10.1109/EEIC.2007.4562598","DOIUrl":"https://doi.org/10.1109/EEIC.2007.4562598","url":null,"abstract":"Continuous energy efficiency improvement in system level and device level is important to compete in the global market Power electronics enables the control of low cost motors, which were not commercially viable for consumer applications before. This paper presents characteristics of two types of motors that have become popular as cost effective replacements for standard induction motors. The characteristics are discussed to highlight the nature of the power electronics controller required.","PeriodicalId":152045,"journal":{"name":"2007 Electrical Insulation Conference and Electrical Manufacturing Expo","volume":"19 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114850409","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}

{"title":"Over-voltage protector for overhead insulated distribution lines","authors":"Guoping Shen, Jian Yuan, Yan Luo","doi":"10.1109/EEIC.2007.4562581","DOIUrl":"https://doi.org/10.1109/EEIC.2007.4562581","url":null,"abstract":"A new type over voltage protector that combining forward against lightning technique of discharge controllable lightning needle with nonlinear technique of ZnO surge arrester together for restraining over voltage had been designed in this paper. This protector was named discharge controllable over voltage protector and had been used for protecting overhead insulated lines from line melted down and line switch off. Its protecting principle is based on disembowelment theory of air- discharge and nonlinear V-A character of current limit unit. The overhead lines may operate more safely and more reliably when the protector installed on. In the paper, lightning impulse test and V-s character test of lightning impulse were applied to confirm the length of gap in series and optimize proper insulation level as well as technical parameters of the protector. The test research results proved that the discharge controllable over voltage protector is not only effectively prevent overhead line from lightning shielding failure, but also effectively prevent overhead line from melted down and switch off faults caused by any reason. Its capability of forward lightning protection and shutting off power frequency current as well as restraining over voltage is more effectively, more reliably and more safely.","PeriodicalId":152045,"journal":{"name":"2007 Electrical Insulation Conference and Electrical Manufacturing Expo","volume":"81 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126237474","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}

{"title":"Epoxy systems for low temperature applications","authors":"M. Rajadhyaksha","doi":"10.1109/EEIC.2007.4562647","DOIUrl":"https://doi.org/10.1109/EEIC.2007.4562647","url":null,"abstract":"Epoxy-based formulated products are finding increased utility in a wide variety of structural and electrical applications that are required to operate in low temperature environments. Cryogenic technology is accelerating the growth in these fields. This versatile thermosetting polymer offers many attractive features such as high mechanical strength, outstanding dielectric characteristics, excellent adhesive properties, very good chemical resistance and excellent thermal endurance. Such features make them materials of choice for high and medium voltage electrical apparatus that operate in below zero Celsius environments. At lower operating temperatures, many factors come into play affecting overall performance. Among these factors are: speed and effectiveness of cure, fracture toughness characteristics, and thermal expansion properties.","PeriodicalId":152045,"journal":{"name":"2007 Electrical Insulation Conference and Electrical Manufacturing Expo","volume":"26 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131594646","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}