Pub Date : 2011-10-01DOI: 10.1109/CEIDP.2011.6232651
H. Wang, V. Inclan, A. Zyuzin, N. Donnangelo, A. Mamishev
Accurate measurement of dielectric properties of granular materials and powders is important in material science, pharmacology, agriculture, and other fields. Granular materials present a wide range of measurement challenges not encountered with solid and liquid samples. This paper presents the calibration process for measurement of granular material properties using a custom-designed dielectric spectroscopy system. The process uses systematic iterative calibration for the individual stages of the measurement circuit, the calibration of the sensor fixture, and the determination of a frequency-dependent phase-shift due to the operational amplifiers in the circuit. The results show that using the calibrated system to measure the air's relative dielectric permittivity noticeably reduces measurement deviation to 0.5%, from more than 30% in non-calibrated mode. Based on the material dielectric signature acquired in the frequency domain, the measurement system can be used to identify a broad variety of granular materials. Since allowing direct contact with the sensor electrodes is undesirable for some materials, this paper demonstrates how insulating the granular material in a thin film during material property measurement can be taken into account.
{"title":"Material property measurement of granular materials using a calibrated dielectric spectroscopy system","authors":"H. Wang, V. Inclan, A. Zyuzin, N. Donnangelo, A. Mamishev","doi":"10.1109/CEIDP.2011.6232651","DOIUrl":"https://doi.org/10.1109/CEIDP.2011.6232651","url":null,"abstract":"Accurate measurement of dielectric properties of granular materials and powders is important in material science, pharmacology, agriculture, and other fields. Granular materials present a wide range of measurement challenges not encountered with solid and liquid samples. This paper presents the calibration process for measurement of granular material properties using a custom-designed dielectric spectroscopy system. The process uses systematic iterative calibration for the individual stages of the measurement circuit, the calibration of the sensor fixture, and the determination of a frequency-dependent phase-shift due to the operational amplifiers in the circuit. The results show that using the calibrated system to measure the air's relative dielectric permittivity noticeably reduces measurement deviation to 0.5%, from more than 30% in non-calibrated mode. Based on the material dielectric signature acquired in the frequency domain, the measurement system can be used to identify a broad variety of granular materials. Since allowing direct contact with the sensor electrodes is undesirable for some materials, this paper demonstrates how insulating the granular material in a thin film during material property measurement can be taken into account.","PeriodicalId":6317,"journal":{"name":"2011 Annual Report Conference on Electrical Insulation and Dielectric Phenomena","volume":"21 1","pages":"280-283"},"PeriodicalIF":0.0,"publicationDate":"2011-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87568019","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 : 2011-10-01DOI: 10.1109/CEIDP.2011.6232751
S. Hvidsten, F. Satre
An attractive application for polypropylene is as high voltage AC or DC cable insulation. The main driving force for using polypropylene is the simpler production technique avoiding degassing treatments, as well as the higher melting temperatures compared to the conventional cross-linked polyethylene (XLPE) Large spherulites are not formed in sPP insulations making this insulation particular attractive. The dielectric response has been measured using miniature cables in frequency domain, using a method based upon measurements of capacitance and dielectric loss. The cables were energized up to 20 kV in the frequency range of 10 mHz to 100 Hz in the temperature range of 30 to 130 °C. It is shown that sPP has significant lower dielectric losses than XLPE and is less sensitive to water absorption in the low frequency regime. However, both insulations showed no field or temperature dependence of the losses close to power frequency.
{"title":"Dielectric response of sPP and XLPE insulations at high temperatures and electric fields","authors":"S. Hvidsten, F. Satre","doi":"10.1109/CEIDP.2011.6232751","DOIUrl":"https://doi.org/10.1109/CEIDP.2011.6232751","url":null,"abstract":"An attractive application for polypropylene is as high voltage AC or DC cable insulation. The main driving force for using polypropylene is the simpler production technique avoiding degassing treatments, as well as the higher melting temperatures compared to the conventional cross-linked polyethylene (XLPE) Large spherulites are not formed in sPP insulations making this insulation particular attractive. The dielectric response has been measured using miniature cables in frequency domain, using a method based upon measurements of capacitance and dielectric loss. The cables were energized up to 20 kV in the frequency range of 10 mHz to 100 Hz in the temperature range of 30 to 130 °C. It is shown that sPP has significant lower dielectric losses than XLPE and is less sensitive to water absorption in the low frequency regime. However, both insulations showed no field or temperature dependence of the losses close to power frequency.","PeriodicalId":6317,"journal":{"name":"2011 Annual Report Conference on Electrical Insulation and Dielectric Phenomena","volume":"281 1","pages":"695-698"},"PeriodicalIF":0.0,"publicationDate":"2011-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78469784","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 : 2011-10-01DOI: 10.1109/CEIDP.2011.6232594
R. Khazaka, S. Diaham, M. Locatelli, C. Trupin, B. Schlegel
Nowadays, polyimides (PIs) are widely used in electronic applications where high temperature operating devices are needed. In order to validate the use of PI as insulating layer in above 200°C applications, the thermal (in inert atmosphere) and thermo-oxidative (in oxidant atmosphere) degradation at high temperature of PI thin films were investigated. The PI films (from 1.5 to 8.6 μm), deposited on stainless steel substrates, were thermally aged in air and in nitrogen (N2) gas at 360°C for several hundreds of hours. The variations of their thickness, surface roughness, electrical conductivity and dielectric strength were measured periodically during the aging. The aging in N2 shows a negligible effect on all the controlled film characteristics in the high temperature region during 800 hours of aging. On the contrary, results show that the life time of the thin PI films aged in air is thickness dependent, and thin films (<; 10 μm) cannot be used in air at 360°C for more than 1000 hours. In air, an average thickness reduction rate of about 7×10-3 μm/h was measured for all the investigated films meaning that the thickness reduction is regulated by the interface with air. The breakdown voltage (measured at 300°C) also shows a thickness dependent reduction rate. In contrast, the breakdown field shows a reduction during the first aging period related to the increase of the surface roughness followed by a quasi stabilization during the rest time of aging. Moreover, a decrease in the dc conductivity measured at 300°C was observed during the first step of aging in air followed by a quasi stabilization. This has been related to changes in the macromolecular structure of the bulk due to oxygen diffusion. Those results indicate that the dielectric property evolutions during aging in air are induced by the oxygen presence, and they allow separating the surface and bulk effects.
{"title":"Thermal and thermo-oxidative aging effects on the dielectric properties of thin polyimide films coated on metal substrate","authors":"R. Khazaka, S. Diaham, M. Locatelli, C. Trupin, B. Schlegel","doi":"10.1109/CEIDP.2011.6232594","DOIUrl":"https://doi.org/10.1109/CEIDP.2011.6232594","url":null,"abstract":"Nowadays, polyimides (PIs) are widely used in electronic applications where high temperature operating devices are needed. In order to validate the use of PI as insulating layer in above 200°C applications, the thermal (in inert atmosphere) and thermo-oxidative (in oxidant atmosphere) degradation at high temperature of PI thin films were investigated. The PI films (from 1.5 to 8.6 μm), deposited on stainless steel substrates, were thermally aged in air and in nitrogen (N2) gas at 360°C for several hundreds of hours. The variations of their thickness, surface roughness, electrical conductivity and dielectric strength were measured periodically during the aging. The aging in N2 shows a negligible effect on all the controlled film characteristics in the high temperature region during 800 hours of aging. On the contrary, results show that the life time of the thin PI films aged in air is thickness dependent, and thin films (<; 10 μm) cannot be used in air at 360°C for more than 1000 hours. In air, an average thickness reduction rate of about 7×10-3 μm/h was measured for all the investigated films meaning that the thickness reduction is regulated by the interface with air. The breakdown voltage (measured at 300°C) also shows a thickness dependent reduction rate. In contrast, the breakdown field shows a reduction during the first aging period related to the increase of the surface roughness followed by a quasi stabilization during the rest time of aging. Moreover, a decrease in the dc conductivity measured at 300°C was observed during the first step of aging in air followed by a quasi stabilization. This has been related to changes in the macromolecular structure of the bulk due to oxygen diffusion. Those results indicate that the dielectric property evolutions during aging in air are induced by the oxygen presence, and they allow separating the surface and bulk effects.","PeriodicalId":6317,"journal":{"name":"2011 Annual Report Conference on Electrical Insulation and Dielectric Phenomena","volume":"29 1","pages":"52-55"},"PeriodicalIF":0.0,"publicationDate":"2011-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76812838","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 : 2011-10-01DOI: 10.1109/CEIDP.2011.6232605
C. Stancu, P. Notingher, L. Badicu
Dielectric response function f(t) of an insulation allows its behavior estimation in any electric field, constant or time variable. Generally, for the f(t) computation, a DC voltage U0 is applied, for a long enough period of time, on the insulation and the resorption (depolarization) current ir (t) is measured. In the present paper, the dielectric response function is determined based on its Fourier transform, taking into account the frequency variation curve of real part of complex permittivity. Thus, the time variation curve of resorption currents and frequency variation curve of real part of complex permittivity have been determined and, based on them, the dielectric response function has been calculated for two different kinds of samples, mineral oil impregnated paper and water treed polyethylene. Finally, the time variation curves of f(t) obtained with both methods are analyzed.
{"title":"Dielectric response function for nonhomogeneous insulations","authors":"C. Stancu, P. Notingher, L. Badicu","doi":"10.1109/CEIDP.2011.6232605","DOIUrl":"https://doi.org/10.1109/CEIDP.2011.6232605","url":null,"abstract":"Dielectric response function f(t) of an insulation allows its behavior estimation in any electric field, constant or time variable. Generally, for the f(t) computation, a DC voltage U0 is applied, for a long enough period of time, on the insulation and the resorption (depolarization) current ir (t) is measured. In the present paper, the dielectric response function is determined based on its Fourier transform, taking into account the frequency variation curve of real part of complex permittivity. Thus, the time variation curve of resorption currents and frequency variation curve of real part of complex permittivity have been determined and, based on them, the dielectric response function has been calculated for two different kinds of samples, mineral oil impregnated paper and water treed polyethylene. Finally, the time variation curves of f(t) obtained with both methods are analyzed.","PeriodicalId":6317,"journal":{"name":"2011 Annual Report Conference on Electrical Insulation and Dielectric Phenomena","volume":"9 1","pages":"97-100"},"PeriodicalIF":0.0,"publicationDate":"2011-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85791868","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 : 2011-10-01DOI: 10.1109/CEIDP.2011.6232689
A. Cavallini, C. G. A. Ramos, G. Montanari, J. Rubio-Serrano, J. A. García-Souto
In this paper, partial discharge measurements on artificial specimens simulating corona, surface and internal partial discharge in paper/oil insulation systems are discussed. Focus is made on a comparative analysis of signals derived through both conventional (conducted electrical signals) and unconventional (acoustic and UltraHigh Frequency emission) techniques. The results indicate that unconventional techniques can provide evidence of partial discharge activity, but are not sufficient to assess the severity of the detected phenomenon. This requires apparent charge measurements conducted through conventional detectors. In the case streamers are observed, narrowband detection (with bandwidths below 50 kHz) must be used to get an accurate estimate of apparent charges.
{"title":"Comparison of ultrasonic, electrical and UHF characteristics of partial discharge emission in oil/paper insulation systems","authors":"A. Cavallini, C. G. A. Ramos, G. Montanari, J. Rubio-Serrano, J. A. García-Souto","doi":"10.1109/CEIDP.2011.6232689","DOIUrl":"https://doi.org/10.1109/CEIDP.2011.6232689","url":null,"abstract":"In this paper, partial discharge measurements on artificial specimens simulating corona, surface and internal partial discharge in paper/oil insulation systems are discussed. Focus is made on a comparative analysis of signals derived through both conventional (conducted electrical signals) and unconventional (acoustic and UltraHigh Frequency emission) techniques. The results indicate that unconventional techniques can provide evidence of partial discharge activity, but are not sufficient to assess the severity of the detected phenomenon. This requires apparent charge measurements conducted through conventional detectors. In the case streamers are observed, narrowband detection (with bandwidths below 50 kHz) must be used to get an accurate estimate of apparent charges.","PeriodicalId":6317,"journal":{"name":"2011 Annual Report Conference on Electrical Insulation and Dielectric Phenomena","volume":"16 1","pages":"440-443"},"PeriodicalIF":0.0,"publicationDate":"2011-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87058462","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 : 2011-10-01DOI: 10.1109/CEIDP.2011.6232720
A. Lipchitz, G. Harvel
Electrohydrodynamic (EHD) phenomena have been shown to enhance heat transfer in a variety of heat transport designs including capillary pumped loops for extraterrestrial nuclear applications. Previously, EHD enhancement has been shown to improve the heat transport of experimental CPLs. Further enhancement with the addition of EHD gas pumps to the vapour phase requires EHD gas pump phenomena and performance to be characterized with respect to gravity to determine the expected enhancement from this arrangement in zero and microgravity environments. In this paper an EHD gas pump is oriented with gravity (inverted), 90° to gravity (horizontal) and against gravity (vertical) to determine the effect gravitational and buoyancy forces have on the flow and heat transport of EHD gas pumps. The flow and temperature profiles of the pump at the outlet are presented to demonstrate the orientation effect gravity and buoyancy imposes on EHD gas pumps. The EHD number is calculated and presented. The paper determines that there is a noticeable orientation effect at lower applied voltages due to the heating effects causing recirculation in the flow being reduced with the aid of buoyancy forces. However, the effect is less noticeable at higher applied voltages due to the stronger EHD forces.
{"title":"Effects of orientation with respect to gravity for a wire-plate convergent angle electrohydrodynamic gas pump","authors":"A. Lipchitz, G. Harvel","doi":"10.1109/CEIDP.2011.6232720","DOIUrl":"https://doi.org/10.1109/CEIDP.2011.6232720","url":null,"abstract":"Electrohydrodynamic (EHD) phenomena have been shown to enhance heat transfer in a variety of heat transport designs including capillary pumped loops for extraterrestrial nuclear applications. Previously, EHD enhancement has been shown to improve the heat transport of experimental CPLs. Further enhancement with the addition of EHD gas pumps to the vapour phase requires EHD gas pump phenomena and performance to be characterized with respect to gravity to determine the expected enhancement from this arrangement in zero and microgravity environments. In this paper an EHD gas pump is oriented with gravity (inverted), 90° to gravity (horizontal) and against gravity (vertical) to determine the effect gravitational and buoyancy forces have on the flow and heat transport of EHD gas pumps. The flow and temperature profiles of the pump at the outlet are presented to demonstrate the orientation effect gravity and buoyancy imposes on EHD gas pumps. The EHD number is calculated and presented. The paper determines that there is a noticeable orientation effect at lower applied voltages due to the heating effects causing recirculation in the flow being reduced with the aid of buoyancy forces. However, the effect is less noticeable at higher applied voltages due to the stronger EHD forces.","PeriodicalId":6317,"journal":{"name":"2011 Annual Report Conference on Electrical Insulation and Dielectric Phenomena","volume":"24 1","pages":"567-570"},"PeriodicalIF":0.0,"publicationDate":"2011-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91126262","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}
With the purpose of deeply understanding behavior of streamer discharge in nitrogen-dielectric, the two-dimensional and self-consistent fluid model of the gas discharge was established based on the electron and ion continuity equations coupled to Poisson's equation. The plasma channel of the negative streamer discharge is studied in this paper by numerical simulation. A program based on the finite element method in its full two-dimension form is developed and employed for the solution of continuity equations of charged particles under the effect of space-charge electric field. Results of two-dimensional simulation of cylindrically symmetric streamer in pure N2 between parallel-plate electrodes are presented. The formation and propagation of negative streamer in numerically was observed. The space electric field distribution, space ions distribution and drift velocity were predicted by the model. The influence of initial conditions and applied voltages on the streamer characteristic was also investigated. The results show that the space electric field and electrons and ions density at the tip of the streamer increase with the propagation of negative streamer. The space electrons density and electric field at the tip of streamer increase, when the ionization density in the initial increase. The propagation velocity and other characteristics of the streamer are influenced by the diameter of the initial charge distribution. For negative streamer, the ionization density and electron density gradient and electric field at the tip increase with increasing applied field.
{"title":"Two-dimensional simulation of the negative streamer in N2 between parallel-plate electrodes","authors":"Zheng Dian-chun, Zhu Shi-hua, Zhang Zhong-lin, Lv Shu-ming","doi":"10.1109/CEIDP.2011.6232767","DOIUrl":"https://doi.org/10.1109/CEIDP.2011.6232767","url":null,"abstract":"With the purpose of deeply understanding behavior of streamer discharge in nitrogen-dielectric, the two-dimensional and self-consistent fluid model of the gas discharge was established based on the electron and ion continuity equations coupled to Poisson's equation. The plasma channel of the negative streamer discharge is studied in this paper by numerical simulation. A program based on the finite element method in its full two-dimension form is developed and employed for the solution of continuity equations of charged particles under the effect of space-charge electric field. Results of two-dimensional simulation of cylindrically symmetric streamer in pure N2 between parallel-plate electrodes are presented. The formation and propagation of negative streamer in numerically was observed. The space electric field distribution, space ions distribution and drift velocity were predicted by the model. The influence of initial conditions and applied voltages on the streamer characteristic was also investigated. The results show that the space electric field and electrons and ions density at the tip of the streamer increase with the propagation of negative streamer. The space electrons density and electric field at the tip of streamer increase, when the ionization density in the initial increase. The propagation velocity and other characteristics of the streamer are influenced by the diameter of the initial charge distribution. For negative streamer, the ionization density and electron density gradient and electric field at the tip increase with increasing applied field.","PeriodicalId":6317,"journal":{"name":"2011 Annual Report Conference on Electrical Insulation and Dielectric Phenomena","volume":"14 1","pages":"760-763"},"PeriodicalIF":0.0,"publicationDate":"2011-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82923300","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 : 2011-10-01DOI: 10.1109/CEIDP.2011.6232716
S. Bessedik, H. Hadi
The importance of the research on insulator pollution has been increased considerably with the rise of the voltage of transmission lines. In order to determine the flashover behavior of polluted high voltage insulators and to identify to physical mechanisms that govern this phenomenon, the researchers have been brought to establish a modeling. In this study after presenting the theoretical and experimental open model, a dynamic arc model has been developed to calculate the flashover. The validity of the model was verified by comparing the computed results with the experimental results of previous researchers and good correlation has been shown.
{"title":"Dynamic arc model of the flashover of the polluted insulators","authors":"S. Bessedik, H. Hadi","doi":"10.1109/CEIDP.2011.6232716","DOIUrl":"https://doi.org/10.1109/CEIDP.2011.6232716","url":null,"abstract":"The importance of the research on insulator pollution has been increased considerably with the rise of the voltage of transmission lines. In order to determine the flashover behavior of polluted high voltage insulators and to identify to physical mechanisms that govern this phenomenon, the researchers have been brought to establish a modeling. In this study after presenting the theoretical and experimental open model, a dynamic arc model has been developed to calculate the flashover. The validity of the model was verified by comparing the computed results with the experimental results of previous researchers and good correlation has been shown.","PeriodicalId":6317,"journal":{"name":"2011 Annual Report Conference on Electrical Insulation and Dielectric Phenomena","volume":"27 1","pages":"550-554"},"PeriodicalIF":0.0,"publicationDate":"2011-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83382588","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 : 2011-10-01DOI: 10.1109/CEIDP.2011.6232613
H. Miyake, R. Uchiyama, S. Numata, Y. Tanaka, T. Takada
We evaluate the dielectric characteristic of polymeric materials for MLI (Multi Layer Insulator, a kind of thermal insulation material) for spacecraft under high energy proton irradiation using the results of space charge distribution and current measurement. Spacecraft have a serious damage due to the electrostatic discharge accident. The electric charges are accumulated in the polymeric materials due to radioactive rays, especially electrons and protons. Those charges become the origin of aging and discharging phenomena. Furthermore, those charging and discharging phenomena becomes a trigger for spacecraft operation anomaly. Therefore, we need to obtain the electric property. From the above reason, we have studied space charge accumulation phenomena in the dielectric bulks using PEA method. In this study, we especially focused polyimide (PI) films for MLI irradiated by high energy proton. While many researchers have studied to discuss the charging phenomena in several dielectric materials irradiated by e-beam with several energies, the charging characteristic in those materials irradiated by proton was not treated. Therefore, we especially focused on an internal charging phenomena in polymeric materials irradiated by a proton. From the results, it is found that positive charges accumulate in the bulk at the position of proton penetration depth. We also have tendency that accumulated charges decreased during the irradiation depended on irradiation current density. We thought that the origin of the phenomenon is produced by RIC. Concerning the confirmation of our prediction based on PEA measurement, we also obtained the conductivity in the PI bulks irradiated by proton using ASTM method. From the above our results, we discuss and estimate the dielectric properties of the PI films irradiated by proton in this paper.
{"title":"Charge accumulation phenomena in PI film irradiated by a proton","authors":"H. Miyake, R. Uchiyama, S. Numata, Y. Tanaka, T. Takada","doi":"10.1109/CEIDP.2011.6232613","DOIUrl":"https://doi.org/10.1109/CEIDP.2011.6232613","url":null,"abstract":"We evaluate the dielectric characteristic of polymeric materials for MLI (Multi Layer Insulator, a kind of thermal insulation material) for spacecraft under high energy proton irradiation using the results of space charge distribution and current measurement. Spacecraft have a serious damage due to the electrostatic discharge accident. The electric charges are accumulated in the polymeric materials due to radioactive rays, especially electrons and protons. Those charges become the origin of aging and discharging phenomena. Furthermore, those charging and discharging phenomena becomes a trigger for spacecraft operation anomaly. Therefore, we need to obtain the electric property. From the above reason, we have studied space charge accumulation phenomena in the dielectric bulks using PEA method. In this study, we especially focused polyimide (PI) films for MLI irradiated by high energy proton. While many researchers have studied to discuss the charging phenomena in several dielectric materials irradiated by e-beam with several energies, the charging characteristic in those materials irradiated by proton was not treated. Therefore, we especially focused on an internal charging phenomena in polymeric materials irradiated by a proton. From the results, it is found that positive charges accumulate in the bulk at the position of proton penetration depth. We also have tendency that accumulated charges decreased during the irradiation depended on irradiation current density. We thought that the origin of the phenomenon is produced by RIC. Concerning the confirmation of our prediction based on PEA measurement, we also obtained the conductivity in the PI bulks irradiated by proton using ASTM method. From the above our results, we discuss and estimate the dielectric properties of the PI films irradiated by proton in this paper.","PeriodicalId":6317,"journal":{"name":"2011 Annual Report Conference on Electrical Insulation and Dielectric Phenomena","volume":"18 1","pages":"129-132"},"PeriodicalIF":0.0,"publicationDate":"2011-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85884380","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 : 2011-10-01DOI: 10.1109/CEIDP.2011.6232706
M. Marzinotto, G. Mazzanti, C. Mazzetti
The impulse test levels play an even more important role for the design of HVDC cables than for HVAC cables. Nevertheless, the selection of both lightning and switching impulse test values for a given power DC intertie are mostly based on numerical simulation and on past experience on similar interties rather than on well-established and standardized practices. In this paper the selection of lightning and switching impulse voltage levels to be applied on short cable lengths in the prequalification and/or type tests is addressed for long DC cable lines (longer than 50 km) taking into account the impulse withstand behaviour with cable length via the enlargement law and the effect of over-voltage attenuation for surges that travel along the cable.
{"title":"Lightning and switching impulse levels selection for long DC cable lines","authors":"M. Marzinotto, G. Mazzanti, C. Mazzetti","doi":"10.1109/CEIDP.2011.6232706","DOIUrl":"https://doi.org/10.1109/CEIDP.2011.6232706","url":null,"abstract":"The impulse test levels play an even more important role for the design of HVDC cables than for HVAC cables. Nevertheless, the selection of both lightning and switching impulse test values for a given power DC intertie are mostly based on numerical simulation and on past experience on similar interties rather than on well-established and standardized practices. In this paper the selection of lightning and switching impulse voltage levels to be applied on short cable lengths in the prequalification and/or type tests is addressed for long DC cable lines (longer than 50 km) taking into account the impulse withstand behaviour with cable length via the enlargement law and the effect of over-voltage attenuation for surges that travel along the cable.","PeriodicalId":6317,"journal":{"name":"2011 Annual Report Conference on Electrical Insulation and Dielectric Phenomena","volume":"119 3 1","pages":"510-513"},"PeriodicalIF":0.0,"publicationDate":"2011-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79741620","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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