Pub Date : 1999-10-26DOI: 10.1109/EEIC.1999.826192
A. B. Strong
The performance of transformers depends directly on the quality of the dielectric medium (fluid). However, this dielectric fluid degrades with use and, at some point, will change sufficiently that the transformer will no longer operate properly. In some cases, the degradation of the dielectric fluid can cause catastrophic failure of the transformer. Therefore, methods to automatically sense the condition of the transformer dielectric material are both useful and compelling. A new device has been developed that allows automatic sensing of the transformer dielectric. This device is small and simple, yet demonstrates a surprising capability to detect subtle changes in the material. The device also detects changes in other nonconductive fluids such as fuels (oils, gasoline, diesel, etc.), polymers, and even for sensing the water content in low conductivity fluids.
{"title":"Automatic sensing of changes in transformer dielectrics","authors":"A. B. Strong","doi":"10.1109/EEIC.1999.826192","DOIUrl":"https://doi.org/10.1109/EEIC.1999.826192","url":null,"abstract":"The performance of transformers depends directly on the quality of the dielectric medium (fluid). However, this dielectric fluid degrades with use and, at some point, will change sufficiently that the transformer will no longer operate properly. In some cases, the degradation of the dielectric fluid can cause catastrophic failure of the transformer. Therefore, methods to automatically sense the condition of the transformer dielectric material are both useful and compelling. A new device has been developed that allows automatic sensing of the transformer dielectric. This device is small and simple, yet demonstrates a surprising capability to detect subtle changes in the material. The device also detects changes in other nonconductive fluids such as fuels (oils, gasoline, diesel, etc.), polymers, and even for sensing the water content in low conductivity fluids.","PeriodicalId":415071,"journal":{"name":"Proceedings: Electrical Insulation Conference and Electrical Manufacturing and Coil Winding Conference (Cat. No.99CH37035)","volume":"50 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1999-10-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117141419","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 : 1999-10-26DOI: 10.1109/EEIC.1999.826181
M. Miller
Thermal power dissipation from vacuum pressure impregnated stator coils to the stator core in turbine generators is a topic of technical importance. In order to increase turbine generator MVA output by increasing current through the coil wire strands, there must be improved thermal conductivity in the stator slot to improve thermal power dissipation capability. A benchmark study of vacuum pressure impregnation (VPI) and global vacuum pressure impregnation (GVPI) stator coil groundwall insulation has been investigated in a previous paper (1997). This paper builds on the model showing a relationship between the stator coil groundwall insulation composition and thermal conductivity. This paper looks at improving the stator slot thermal conductivity by increasing the thermal conductivity of the stator coil groundwall insulation and the region between the stator coil and the core. The models generated provide a design tool which can estimate the thermal conductivity in the stator slot, from the coil wire strands to the core.
{"title":"Turbine generator stator slot thermal conductivity","authors":"M. Miller","doi":"10.1109/EEIC.1999.826181","DOIUrl":"https://doi.org/10.1109/EEIC.1999.826181","url":null,"abstract":"Thermal power dissipation from vacuum pressure impregnated stator coils to the stator core in turbine generators is a topic of technical importance. In order to increase turbine generator MVA output by increasing current through the coil wire strands, there must be improved thermal conductivity in the stator slot to improve thermal power dissipation capability. A benchmark study of vacuum pressure impregnation (VPI) and global vacuum pressure impregnation (GVPI) stator coil groundwall insulation has been investigated in a previous paper (1997). This paper builds on the model showing a relationship between the stator coil groundwall insulation composition and thermal conductivity. This paper looks at improving the stator slot thermal conductivity by increasing the thermal conductivity of the stator coil groundwall insulation and the region between the stator coil and the core. The models generated provide a design tool which can estimate the thermal conductivity in the stator slot, from the coil wire strands to the core.","PeriodicalId":415071,"journal":{"name":"Proceedings: Electrical Insulation Conference and Electrical Manufacturing and Coil Winding Conference (Cat. No.99CH37035)","volume":"18 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1999-10-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117147448","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 : 1999-10-26DOI: 10.1109/EEIC.1999.826294
M. Klein, D. Norton
Industry analysts agree that the legacy PLC infrastructure is being replaced with a far more productive and cost-effective PC-based automation infrastructure. With PC-based control, you can drive faster time to market, reduce downtime, and access production data across the enterprise, with tools that enable continuous improvement in your manufacturing process.
{"title":"Increasing the productivity and profitability of machine builders using PC-based control","authors":"M. Klein, D. Norton","doi":"10.1109/EEIC.1999.826294","DOIUrl":"https://doi.org/10.1109/EEIC.1999.826294","url":null,"abstract":"Industry analysts agree that the legacy PLC infrastructure is being replaced with a far more productive and cost-effective PC-based automation infrastructure. With PC-based control, you can drive faster time to market, reduce downtime, and access production data across the enterprise, with tools that enable continuous improvement in your manufacturing process.","PeriodicalId":415071,"journal":{"name":"Proceedings: Electrical Insulation Conference and Electrical Manufacturing and Coil Winding Conference (Cat. No.99CH37035)","volume":"17 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1999-10-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127291440","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 : 1999-10-26DOI: 10.1109/EEIC.1999.826245
C. Bretz, E. Wiedenbrug
In the past few years many companies have been experimenting with the use of bondable wire processes. The advantages to this type of process include reduced cycle times, less handling, and virtually no environmental impact. Using a bondable wire process can allow a manufacturer to completely build a product on one line without a lot of work in process. The process can be set to supply a product off a line in less than 10 seconds. The systems can be designed with tooling to form the product, test the product, and bond the product in one station. In some cases the product could be packaged immediately after this station. This paper investigates the use of DC power sources to thermally activate the bondable adhesive. The methodology of determining how much power is needed to heat the coil in the required time is investigated. A theoretical approach of estimated power verses bond time is supported by an experimental approach. A method for determining final temperature and temperature overshoot is presented. We discuss the advantages of using a constant voltage source compared to a constant current source.
{"title":"A self bonding wire process","authors":"C. Bretz, E. Wiedenbrug","doi":"10.1109/EEIC.1999.826245","DOIUrl":"https://doi.org/10.1109/EEIC.1999.826245","url":null,"abstract":"In the past few years many companies have been experimenting with the use of bondable wire processes. The advantages to this type of process include reduced cycle times, less handling, and virtually no environmental impact. Using a bondable wire process can allow a manufacturer to completely build a product on one line without a lot of work in process. The process can be set to supply a product off a line in less than 10 seconds. The systems can be designed with tooling to form the product, test the product, and bond the product in one station. In some cases the product could be packaged immediately after this station. This paper investigates the use of DC power sources to thermally activate the bondable adhesive. The methodology of determining how much power is needed to heat the coil in the required time is investigated. A theoretical approach of estimated power verses bond time is supported by an experimental approach. A method for determining final temperature and temperature overshoot is presented. We discuss the advantages of using a constant voltage source compared to a constant current source.","PeriodicalId":415071,"journal":{"name":"Proceedings: Electrical Insulation Conference and Electrical Manufacturing and Coil Winding Conference (Cat. No.99CH37035)","volume":"172 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1999-10-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125939002","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 : 1999-10-26DOI: 10.1109/EEIC.1999.826249
S. Trout, Y. Zhilichev
Magnets based on neodymium iron boron (NdFeB) alloys have been available for about 15 years, yet many people are frustrated in their attempts to incorporate this material into new devices. These are problems that cannot be solved by research focused on higher energy product materials, nor are they the result of the three well-known objections to NdFeB magnets: higher cost per kilogram than ferrite, limited maximum operating temperature and poor corrosion resistance when uncoated. The authors address problems due to a lack of understanding by many design engineers on how to correctly use magnets. They review several common design situations and offer ways to improve device performance through the effective use of NdFeB.
{"title":"Effective use of neodymium iron boron magnets, case studies","authors":"S. Trout, Y. Zhilichev","doi":"10.1109/EEIC.1999.826249","DOIUrl":"https://doi.org/10.1109/EEIC.1999.826249","url":null,"abstract":"Magnets based on neodymium iron boron (NdFeB) alloys have been available for about 15 years, yet many people are frustrated in their attempts to incorporate this material into new devices. These are problems that cannot be solved by research focused on higher energy product materials, nor are they the result of the three well-known objections to NdFeB magnets: higher cost per kilogram than ferrite, limited maximum operating temperature and poor corrosion resistance when uncoated. The authors address problems due to a lack of understanding by many design engineers on how to correctly use magnets. They review several common design situations and offer ways to improve device performance through the effective use of NdFeB.","PeriodicalId":415071,"journal":{"name":"Proceedings: Electrical Insulation Conference and Electrical Manufacturing and Coil Winding Conference (Cat. No.99CH37035)","volume":"107 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1999-10-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123234327","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 : 1999-10-26DOI: 10.1109/EEIC.1999.826188
J. Horwath, D. Schweickart
The surface degradation of polyethylene insulators under high electrical stress can be investigated using several surface techniques in conjunction with discharge current measurements. Degradation occurred in air with relative humidities of 25 to 75 percent. The electrical discharge measurements include both pulse (partial discharge) and direct current (DC) values. Humidity influences the partial discharge and DC currents. At higher relative humidities partial discharge current increases and DC current decreases. The surface analysis techniques include surface resistivity, X-ray photoelectron spectroscopy (XPS) and atomic force microscopy (AFM) roughness measurements. Measurement of surface resistivity is dependent on relative humidity. Surface resistivity decreases with increasing relative humidity which may be a boundary condition for decreased discharge currents. The measurement techniques necessary to quantify such parameters are discussed. The utility of antioxidants for retardation of electrical degradation is also investigated. Antioxidant performance for thermal stabilization of thermoplastics is well established through tests such as oxidative induction time tests. Proposed chemical mechanisms for electric field induced degradation are similar to chemical mechanisms for thermally induced degradation. The performance of antioxidants as high electrical stress stabilizers is reported, as measured by XPS.
{"title":"Electrical, physical and chemical measurements on electric field degraded polyethylene","authors":"J. Horwath, D. Schweickart","doi":"10.1109/EEIC.1999.826188","DOIUrl":"https://doi.org/10.1109/EEIC.1999.826188","url":null,"abstract":"The surface degradation of polyethylene insulators under high electrical stress can be investigated using several surface techniques in conjunction with discharge current measurements. Degradation occurred in air with relative humidities of 25 to 75 percent. The electrical discharge measurements include both pulse (partial discharge) and direct current (DC) values. Humidity influences the partial discharge and DC currents. At higher relative humidities partial discharge current increases and DC current decreases. The surface analysis techniques include surface resistivity, X-ray photoelectron spectroscopy (XPS) and atomic force microscopy (AFM) roughness measurements. Measurement of surface resistivity is dependent on relative humidity. Surface resistivity decreases with increasing relative humidity which may be a boundary condition for decreased discharge currents. The measurement techniques necessary to quantify such parameters are discussed. The utility of antioxidants for retardation of electrical degradation is also investigated. Antioxidant performance for thermal stabilization of thermoplastics is well established through tests such as oxidative induction time tests. Proposed chemical mechanisms for electric field induced degradation are similar to chemical mechanisms for thermally induced degradation. The performance of antioxidants as high electrical stress stabilizers is reported, as measured by XPS.","PeriodicalId":415071,"journal":{"name":"Proceedings: Electrical Insulation Conference and Electrical Manufacturing and Coil Winding Conference (Cat. No.99CH37035)","volume":"152 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1999-10-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123527135","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 : 1999-10-26DOI: 10.1109/EEIC.1999.826174
D. Acheson
In today's global economy, every advantage must be utilized to remain competitive. Reduced product development times have become a critical component in the matrix of bringing quality consumer goods to market. This paper suggests the implementation of 3 dimensional mechanical computer aided design (MCAD) software (specifically parametric packages) as well as other technologies that are shaping the way we will do business in the new millennium. In addition to MCAD tools, collaborative design environments (not based on geographical constraints) are rapidly becoming the standard corporate model. Namely, collaborative Internet environments. It should be obvious that the Internet is merely in its infancy stage at this point and is poised to weave itself into every corner of the business sector (and much of our personal lives as well). An additional focus of this paper is to provide background information on several new technologies that should be considered for use in virtually all design and manufacturing facilities.
{"title":"Utilizing parametric modeling design software in the motor manufacturing industry","authors":"D. Acheson","doi":"10.1109/EEIC.1999.826174","DOIUrl":"https://doi.org/10.1109/EEIC.1999.826174","url":null,"abstract":"In today's global economy, every advantage must be utilized to remain competitive. Reduced product development times have become a critical component in the matrix of bringing quality consumer goods to market. This paper suggests the implementation of 3 dimensional mechanical computer aided design (MCAD) software (specifically parametric packages) as well as other technologies that are shaping the way we will do business in the new millennium. In addition to MCAD tools, collaborative design environments (not based on geographical constraints) are rapidly becoming the standard corporate model. Namely, collaborative Internet environments. It should be obvious that the Internet is merely in its infancy stage at this point and is poised to weave itself into every corner of the business sector (and much of our personal lives as well). An additional focus of this paper is to provide background information on several new technologies that should be considered for use in virtually all design and manufacturing facilities.","PeriodicalId":415071,"journal":{"name":"Proceedings: Electrical Insulation Conference and Electrical Manufacturing and Coil Winding Conference (Cat. No.99CH37035)","volume":"24 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1999-10-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115050784","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 : 1999-10-26DOI: 10.1109/EEIC.1999.826278
H. Meuche, M. Esguerra
An overview for ferrite core selection (core shapes and materials) for signal applications is given. It is shown that distortion k/sub 3/ and insertion loss over the frequency range a/sub c/(f) are the key functions in transformer design for xDSL-applications. Parameters called the core distortion factor (CDF) and shape distortion factor (SDF) are helpful in the selection of the core type. The harmonic distortion under circuit conditions can be calculated with a distortion transformer coefficient (DTC) from k/sub 3/. This factor is important in order to correlate the in-circuit third harmonic distortion with the /spl eta//sub B/-measurements. DTC considers circuit conditions for known impedance conditions.
{"title":"Ferrite cores for xDSL: optimum selection","authors":"H. Meuche, M. Esguerra","doi":"10.1109/EEIC.1999.826278","DOIUrl":"https://doi.org/10.1109/EEIC.1999.826278","url":null,"abstract":"An overview for ferrite core selection (core shapes and materials) for signal applications is given. It is shown that distortion k/sub 3/ and insertion loss over the frequency range a/sub c/(f) are the key functions in transformer design for xDSL-applications. Parameters called the core distortion factor (CDF) and shape distortion factor (SDF) are helpful in the selection of the core type. The harmonic distortion under circuit conditions can be calculated with a distortion transformer coefficient (DTC) from k/sub 3/. This factor is important in order to correlate the in-circuit third harmonic distortion with the /spl eta//sub B/-measurements. DTC considers circuit conditions for known impedance conditions.","PeriodicalId":415071,"journal":{"name":"Proceedings: Electrical Insulation Conference and Electrical Manufacturing and Coil Winding Conference (Cat. No.99CH37035)","volume":"65 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1999-10-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129722885","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 : 1999-10-26DOI: 10.1109/EEIC.1999.826206
M. Hoof, S. Lanz
A short overview is given of typical PD sources within large rotating machines. Characteristic pros and cons of online and offline measurements are presented and their significance with regard to condition based machine maintenance is discussed. The possibilities as well as the limitations of PD measurements as a tool to assess the insulation conditions of rotating machines are outlined. Examples are given for online PD measurements on generators that allow a clear diagnostic decision and therefore a reliable condition assessment to be obtained. However, it is additionally shown that PD measurements have some intrinsic limitations and therefore can not detect virtually all insulation related problems.
{"title":"PD diagnostics on rotating machines. Possibilities and limitations","authors":"M. Hoof, S. Lanz","doi":"10.1109/EEIC.1999.826206","DOIUrl":"https://doi.org/10.1109/EEIC.1999.826206","url":null,"abstract":"A short overview is given of typical PD sources within large rotating machines. Characteristic pros and cons of online and offline measurements are presented and their significance with regard to condition based machine maintenance is discussed. The possibilities as well as the limitations of PD measurements as a tool to assess the insulation conditions of rotating machines are outlined. Examples are given for online PD measurements on generators that allow a clear diagnostic decision and therefore a reliable condition assessment to be obtained. However, it is additionally shown that PD measurements have some intrinsic limitations and therefore can not detect virtually all insulation related problems.","PeriodicalId":415071,"journal":{"name":"Proceedings: Electrical Insulation Conference and Electrical Manufacturing and Coil Winding Conference (Cat. No.99CH37035)","volume":"120 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1999-10-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121564572","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 : 1999-10-26DOI: 10.1109/EEIC.1999.826261
E. Lemke, T. Strehl
For preventive diagnosis of HV equipment, different measuring procedures are in use, such as the detection and analysis of PD phenomena as well as the measurement of the capacitance and loss factor. The paper reports on the integration of such different measuring systems to a common, compact and computer based device. This offers for the first time the possibility of a simultaneous measurement of both impedance-parameters of HV insulation and partial discharges. PD faults can be located simultaneously. For analyzing characteristic PD types, a database expert system is integrated. So the global insulation condition can be assessed in a complex manner.
{"title":"Advanced measuring system for the analysis of dielectric parameters including PD events","authors":"E. Lemke, T. Strehl","doi":"10.1109/EEIC.1999.826261","DOIUrl":"https://doi.org/10.1109/EEIC.1999.826261","url":null,"abstract":"For preventive diagnosis of HV equipment, different measuring procedures are in use, such as the detection and analysis of PD phenomena as well as the measurement of the capacitance and loss factor. The paper reports on the integration of such different measuring systems to a common, compact and computer based device. This offers for the first time the possibility of a simultaneous measurement of both impedance-parameters of HV insulation and partial discharges. PD faults can be located simultaneously. For analyzing characteristic PD types, a database expert system is integrated. So the global insulation condition can be assessed in a complex manner.","PeriodicalId":415071,"journal":{"name":"Proceedings: Electrical Insulation Conference and Electrical Manufacturing and Coil Winding Conference (Cat. No.99CH37035)","volume":"67 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1999-10-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126253683","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}
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