Pub Date : 2016-07-03DOI: 10.1109/ICD.2016.7547746
K. Zhou, Kangle Li, Mingliang Yang, Ming Huang, Yusong He
In this paper, the effect of mechanical orientation is presented to understand abnormal water tree shapes. For the XLPE samples, the possible mechanical orientation of XLPE insulation was simulated by inserting a heated metal needle into the samples. After that, one XLPE sample (comparison sample) was selected to be observed for stress strips (the macroscopic morphologies of oriented XLPE materials) using a polarizing microscope, and the other samples were subjected to accelerated water tree aging experiment for water tree analysis. The results show that there are abnormal water tree shapes in the XLPE samples, which are very similar to the morphologies of stress strips observed in the comparison sample. Because of the anisotropy in oriented XLPE materials, in orientation direction, the propagation of water trees is promoted, while in the perpendicular direction, the propagation of water trees is inhibited As a result, abnormal water tree shapes were observed. The results indicate that the mechanical orientation of XLPE materials plays a leading role in the propagation direction of water trees to a large extent.
{"title":"Insight into the influence of mechanical orientation on water tree propagation according to abnormal water tree shapes","authors":"K. Zhou, Kangle Li, Mingliang Yang, Ming Huang, Yusong He","doi":"10.1109/ICD.2016.7547746","DOIUrl":"https://doi.org/10.1109/ICD.2016.7547746","url":null,"abstract":"In this paper, the effect of mechanical orientation is presented to understand abnormal water tree shapes. For the XLPE samples, the possible mechanical orientation of XLPE insulation was simulated by inserting a heated metal needle into the samples. After that, one XLPE sample (comparison sample) was selected to be observed for stress strips (the macroscopic morphologies of oriented XLPE materials) using a polarizing microscope, and the other samples were subjected to accelerated water tree aging experiment for water tree analysis. The results show that there are abnormal water tree shapes in the XLPE samples, which are very similar to the morphologies of stress strips observed in the comparison sample. Because of the anisotropy in oriented XLPE materials, in orientation direction, the propagation of water trees is promoted, while in the perpendicular direction, the propagation of water trees is inhibited As a result, abnormal water tree shapes were observed. The results indicate that the mechanical orientation of XLPE materials plays a leading role in the propagation direction of water trees to a large extent.","PeriodicalId":306397,"journal":{"name":"2016 IEEE International Conference on Dielectrics (ICD)","volume":"794 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-07-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121218045","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 : 2016-07-03DOI: 10.1109/ICD.2016.7547760
O. Emelyanov, A. Plotnikov
Modern multilayer ceramic capacitors (MLCCs) with X7R and Y5V dielectrics have been investigated in charging and discharging pulsed modes. The mathematical model that takes into account the capacitance dependence on applied voltage has been proposed. Analytical calculations of the voltage, current, and stored electrical energy in MLCCs have been carried out. The model adequacy has been confirmed by experimental investigations.
{"title":"Ferroelectric capacitors in pulsed modes: Experimental study and analytical calculations","authors":"O. Emelyanov, A. Plotnikov","doi":"10.1109/ICD.2016.7547760","DOIUrl":"https://doi.org/10.1109/ICD.2016.7547760","url":null,"abstract":"Modern multilayer ceramic capacitors (MLCCs) with X7R and Y5V dielectrics have been investigated in charging and discharging pulsed modes. The mathematical model that takes into account the capacitance dependence on applied voltage has been proposed. Analytical calculations of the voltage, current, and stored electrical energy in MLCCs have been carried out. The model adequacy has been confirmed by experimental investigations.","PeriodicalId":306397,"journal":{"name":"2016 IEEE International Conference on Dielectrics (ICD)","volume":"2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-07-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131128784","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 : 2016-07-03DOI: 10.1109/ICD.2016.7547758
Zhong Zheng, Wenbo Gong, Yu Zhi-cheng, H. Du, Wei Li, Lei Shi
Detection of crackle discharge on GIS spacer from the interferences such as corona in SF6 and surface discharge is of great interests in the evaluation of GIS health conditions. The spacer insulation deteriorates quickly when such discharges occur along small crackles on spacer surface. This paper presents two approaches to differentiate three types of discharges, i.e., corona in SF6, surface discharge and crackle discharge. The former can be distinguished from the latter two by analyzing the phase resolved partial discharge pattern. Further analysis of the decomposed gases accumulated from discharges reveals that CF4 is a useful indicator for discharge on spacer, and H2 occurs only with crackle discharge. Thus the combination of the above two measures provides powerful aids in the detection of crackle discharge in GIS.
{"title":"Crackle discharge detection on GIS spacer through partial discharge test and decomposed gas analysis of SF6","authors":"Zhong Zheng, Wenbo Gong, Yu Zhi-cheng, H. Du, Wei Li, Lei Shi","doi":"10.1109/ICD.2016.7547758","DOIUrl":"https://doi.org/10.1109/ICD.2016.7547758","url":null,"abstract":"Detection of crackle discharge on GIS spacer from the interferences such as corona in SF6 and surface discharge is of great interests in the evaluation of GIS health conditions. The spacer insulation deteriorates quickly when such discharges occur along small crackles on spacer surface. This paper presents two approaches to differentiate three types of discharges, i.e., corona in SF6, surface discharge and crackle discharge. The former can be distinguished from the latter two by analyzing the phase resolved partial discharge pattern. Further analysis of the decomposed gases accumulated from discharges reveals that CF4 is a useful indicator for discharge on spacer, and H2 occurs only with crackle discharge. Thus the combination of the above two measures provides powerful aids in the detection of crackle discharge in GIS.","PeriodicalId":306397,"journal":{"name":"2016 IEEE International Conference on Dielectrics (ICD)","volume":"36 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-07-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114510846","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 : 2016-07-03DOI: 10.1109/ICD.2016.7547526
H. Yahyaoui, P. Notingher, S. Agnel, C. Perrier, Y. Kieffel
The dc breakdown strength of an epoxy resin and of polytetrafluorethylene containing mineral fillers is investigated in order to consider their use in high voltage dc applications. Results obtained at temperatures between 25°C and 85°C with voltage rates from 0.2 kV/s to 8 kV/s are presented and analyzed. The performance and the behavior of the materials are discussed.
{"title":"Electrical breakdown of epoxy and PTFE under dc conditions","authors":"H. Yahyaoui, P. Notingher, S. Agnel, C. Perrier, Y. Kieffel","doi":"10.1109/ICD.2016.7547526","DOIUrl":"https://doi.org/10.1109/ICD.2016.7547526","url":null,"abstract":"The dc breakdown strength of an epoxy resin and of polytetrafluorethylene containing mineral fillers is investigated in order to consider their use in high voltage dc applications. Results obtained at temperatures between 25°C and 85°C with voltage rates from 0.2 kV/s to 8 kV/s are presented and analyzed. The performance and the behavior of the materials are discussed.","PeriodicalId":306397,"journal":{"name":"2016 IEEE International Conference on Dielectrics (ICD)","volume":"2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-07-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114433928","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 : 2016-07-03DOI: 10.1109/ICD.2016.7547715
Arshad, A. Nekahi, S. McMeekin, M. Farzaneh
This paper investigates the effect of pollution severity and relative humidity on the performance of silicone rubber and ethylene propylene diene monomer (EPDM) insulators. Rectangular samples of silicone rubber and EPDM were used for the tests. The ramp test method was used to measure flashover voltage and leakage current at different climate conditions. Flashover voltage, arc inception voltage, as well as surface resistance of silicone rubber and EPDM coating materials were measured at various pollution severity and relative humidity levels in a fog chamber. Experimental results showed a decrease in flashover voltage, arc inception voltage and surface resistance with an increase in pollution severity and relative humidity. The result of this study can be used in the selection of polymeric insulators for contaminated and humid environments.
{"title":"Performance comparison of silicone rubber and EPDM insulators in humid and contaminated environments","authors":"Arshad, A. Nekahi, S. McMeekin, M. Farzaneh","doi":"10.1109/ICD.2016.7547715","DOIUrl":"https://doi.org/10.1109/ICD.2016.7547715","url":null,"abstract":"This paper investigates the effect of pollution severity and relative humidity on the performance of silicone rubber and ethylene propylene diene monomer (EPDM) insulators. Rectangular samples of silicone rubber and EPDM were used for the tests. The ramp test method was used to measure flashover voltage and leakage current at different climate conditions. Flashover voltage, arc inception voltage, as well as surface resistance of silicone rubber and EPDM coating materials were measured at various pollution severity and relative humidity levels in a fog chamber. Experimental results showed a decrease in flashover voltage, arc inception voltage and surface resistance with an increase in pollution severity and relative humidity. The result of this study can be used in the selection of polymeric insulators for contaminated and humid environments.","PeriodicalId":306397,"journal":{"name":"2016 IEEE International Conference on Dielectrics (ICD)","volume":"144 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-07-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123174037","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 : 2016-07-03DOI: 10.1109/ICD.2016.7547569
J. Riffaud, V. Griseri, L. Berquez
Since many years, the behavior of dielectric materials is studied for the energy transportation or space applications. In our case, the Pulsed Electro Acoustic (PEA) method is selected to determine the space charges distribution in polymers submitted to an electron beam. In this work, the PEA measurements in non-contact mode during electronic irradiation are made to evaluate the charge injection dynamic. The measurements are realized with different irradiation conditions as different electronic fluxes and kinetic energies. Then a long relaxation step is performed to monitor the evolution of the injected space charges trapped in the bulk. The results concerning the relaxation phase are discussed in particular to try to explain the appearance of positive charge carriers at the sample surface.
{"title":"Time-resolved space charge measurements during electronic irradiation","authors":"J. Riffaud, V. Griseri, L. Berquez","doi":"10.1109/ICD.2016.7547569","DOIUrl":"https://doi.org/10.1109/ICD.2016.7547569","url":null,"abstract":"Since many years, the behavior of dielectric materials is studied for the energy transportation or space applications. In our case, the Pulsed Electro Acoustic (PEA) method is selected to determine the space charges distribution in polymers submitted to an electron beam. In this work, the PEA measurements in non-contact mode during electronic irradiation are made to evaluate the charge injection dynamic. The measurements are realized with different irradiation conditions as different electronic fluxes and kinetic energies. Then a long relaxation step is performed to monitor the evolution of the injected space charges trapped in the bulk. The results concerning the relaxation phase are discussed in particular to try to explain the appearance of positive charge carriers at the sample surface.","PeriodicalId":306397,"journal":{"name":"2016 IEEE International Conference on Dielectrics (ICD)","volume":"40 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-07-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123387200","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 : 2016-07-03DOI: 10.1109/ICD.2016.7547745
F. Baudoin, S. Le Roy, G. Teyssèdre, C. Laurent, I. Alhossen, F. Bugarin, S. Segonds, N. Binaud
This paper aims at carrying out a parameters sensitivity analysis on a charge transport model using an approach based on the Sobol's method. Charge transport models generally encompass a large number of unknown or ill-defined parameters, typically 10, that interact to produce macroscopic response observable through e.g. space charge density profiles and external current measurements. However, the various physical processes of the model have different impact on the predicted behaviour. The Sobol' approach applied herein is used to study how the variation of the current density and charges density can be quantitatively apportioned to the variation of the model input parameters.
{"title":"Parameters sensitivity analysis in charge transport model using Sobol indexes for optimization purpose","authors":"F. Baudoin, S. Le Roy, G. Teyssèdre, C. Laurent, I. Alhossen, F. Bugarin, S. Segonds, N. Binaud","doi":"10.1109/ICD.2016.7547745","DOIUrl":"https://doi.org/10.1109/ICD.2016.7547745","url":null,"abstract":"This paper aims at carrying out a parameters sensitivity analysis on a charge transport model using an approach based on the Sobol's method. Charge transport models generally encompass a large number of unknown or ill-defined parameters, typically 10, that interact to produce macroscopic response observable through e.g. space charge density profiles and external current measurements. However, the various physical processes of the model have different impact on the predicted behaviour. The Sobol' approach applied herein is used to study how the variation of the current density and charges density can be quantitatively apportioned to the variation of the model input parameters.","PeriodicalId":306397,"journal":{"name":"2016 IEEE International Conference on Dielectrics (ICD)","volume":"161 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-07-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123263687","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 : 2016-07-03DOI: 10.1109/ICD.2016.7547730
Chang Liu, W. Zhang, Man Xu, Lei Shi, Yutong Zhao
Pressboard, a common kind of electrical insulating material, is widely used in the gas insulator transformer (GIT). While a GIT was in operation, the properties of the pressboard changed under the influence of sulfur hexafluoride (SF6) and heat. In this paper, pressboard was subjected to an accelerated aging test in SF6 atmosphere at different temperatures for varying durations. In the research several tests were conducted, including thermogravimetric analysis (TGA), Fourier transform infrared spectroscopy (FTIR), a bending test, scanning electron microscopy (SEM), a dielectric properties test, and a polymerization degree test. These were carried out to research the heat stability, mechanical properties, dielectric properties, and microstructure of the pressboard at different stages of aging: The reasons for these changes could be discovered by analyzing the results. The results showed that thermal degradation of cellulose at high temperature was the main aging factor in pressboard during the thermal aging process in a SF6 atmosphere, which also caused deterioration in the heat stability of pressboard. The mechanical properties of the pressboard deteriorated as thermal aging increased, while dielectric properties increased which were indicated by the decrease in electric inductivity and dielectric loss, and the increase in electrical resistivity. The main causes for these changes were the fracturing of the main chain of the cellulose molecules and a decrease in polar groups, such as hydroxyl, which caused a decline in the hydrophilia of the pressboard. As a consequence, the water content and the number of hydrogen bonds in the materials decreased, leading to structural degradation and a decrease in polarity of the pressboard.
{"title":"A study of aging property of pressboard in gas insulator transformer","authors":"Chang Liu, W. Zhang, Man Xu, Lei Shi, Yutong Zhao","doi":"10.1109/ICD.2016.7547730","DOIUrl":"https://doi.org/10.1109/ICD.2016.7547730","url":null,"abstract":"Pressboard, a common kind of electrical insulating material, is widely used in the gas insulator transformer (GIT). While a GIT was in operation, the properties of the pressboard changed under the influence of sulfur hexafluoride (SF6) and heat. In this paper, pressboard was subjected to an accelerated aging test in SF6 atmosphere at different temperatures for varying durations. In the research several tests were conducted, including thermogravimetric analysis (TGA), Fourier transform infrared spectroscopy (FTIR), a bending test, scanning electron microscopy (SEM), a dielectric properties test, and a polymerization degree test. These were carried out to research the heat stability, mechanical properties, dielectric properties, and microstructure of the pressboard at different stages of aging: The reasons for these changes could be discovered by analyzing the results. The results showed that thermal degradation of cellulose at high temperature was the main aging factor in pressboard during the thermal aging process in a SF6 atmosphere, which also caused deterioration in the heat stability of pressboard. The mechanical properties of the pressboard deteriorated as thermal aging increased, while dielectric properties increased which were indicated by the decrease in electric inductivity and dielectric loss, and the increase in electrical resistivity. The main causes for these changes were the fracturing of the main chain of the cellulose molecules and a decrease in polar groups, such as hydroxyl, which caused a decline in the hydrophilia of the pressboard. As a consequence, the water content and the number of hydrogen bonds in the materials decreased, leading to structural degradation and a decrease in polarity of the pressboard.","PeriodicalId":306397,"journal":{"name":"2016 IEEE International Conference on Dielectrics (ICD)","volume":"31 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-07-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123691991","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 : 2016-07-03DOI: 10.1109/ICD.2016.7547768
K. Hencken, A. Abbasi
This paper investigates the necessary steps required to analyze the results of a PEA measurement. It is shown, that in a mixed frequency-space presentation it can be seen as a two-step process of deconvolution of the signal and reconstruction of the space charge using the acoustic Green's function. It is discussed how the knowledge of the expected signal can be used to improve the deconvolution and how attenuation and dispersion effects can be taken into account in an analytic approach. The techniques are finally applied to both simulated and real measurement data.
{"title":"Analysis of the deconvolution and reconstruction of PEA signals for HV insulation materials","authors":"K. Hencken, A. Abbasi","doi":"10.1109/ICD.2016.7547768","DOIUrl":"https://doi.org/10.1109/ICD.2016.7547768","url":null,"abstract":"This paper investigates the necessary steps required to analyze the results of a PEA measurement. It is shown, that in a mixed frequency-space presentation it can be seen as a two-step process of deconvolution of the signal and reconstruction of the space charge using the acoustic Green's function. It is discussed how the knowledge of the expected signal can be used to improve the deconvolution and how attenuation and dispersion effects can be taken into account in an analytic approach. The techniques are finally applied to both simulated and real measurement data.","PeriodicalId":306397,"journal":{"name":"2016 IEEE International Conference on Dielectrics (ICD)","volume":"57 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-07-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121909958","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 : 2016-07-03DOI: 10.1109/ICD.2016.7547772
Zheng Dianchun, Wei Hongqing, Zhu Bo, Li Wei, Ren Zhigang
In order to absolutely understand the microscopic process of discharge development at atmospheric pressure, the experiment of 5mm air gap discharge in the condition of rod-plate electrode is carried out, and not only the images of discharge process are recorded by intensification charge-coupled device, but also the discharge spectrum is captured. Furthermore, the hydrodynamic model is also adopted to reveal the microscopic mechanism of the 5mm air gap discharge. According to experimental results, electron temperature is estimated to be about 3.15eV. On the other hand, the simulation results show that the discharge process of the 5mm air gap could be divided into three stages: the electron avalanche stage, the streamer formation stage and streamer development stage according to the change of the peak value of the electron density.
{"title":"Research on microscopic process of 5mm air gap discharge at atmospheric pressure","authors":"Zheng Dianchun, Wei Hongqing, Zhu Bo, Li Wei, Ren Zhigang","doi":"10.1109/ICD.2016.7547772","DOIUrl":"https://doi.org/10.1109/ICD.2016.7547772","url":null,"abstract":"In order to absolutely understand the microscopic process of discharge development at atmospheric pressure, the experiment of 5mm air gap discharge in the condition of rod-plate electrode is carried out, and not only the images of discharge process are recorded by intensification charge-coupled device, but also the discharge spectrum is captured. Furthermore, the hydrodynamic model is also adopted to reveal the microscopic mechanism of the 5mm air gap discharge. According to experimental results, electron temperature is estimated to be about 3.15eV. On the other hand, the simulation results show that the discharge process of the 5mm air gap could be divided into three stages: the electron avalanche stage, the streamer formation stage and streamer development stage according to the change of the peak value of the electron density.","PeriodicalId":306397,"journal":{"name":"2016 IEEE International Conference on Dielectrics (ICD)","volume":"44 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-07-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122577451","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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