The Experts below are selected from a list of 264 Experts worldwide ranked by ideXlab platform
V. A. Sidorov - One of the best experts on this subject based on the ideXlab platform.
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Change of Dielectric Strength of vacuum interrupters in process of life-time degradation
Proceedings - International Symposium on Discharges and Electrical Insulation in Vacuum ISDEIV, 2010Co-Authors: D. F. Alferov, L.a. Ryl'skaya, A. A. Pertsev, V. A. SidorovAbstract:60 kV vacuum interrupters (VI) for 110 kV circuit-breakers are investigated. Reduction of Dielectric Strength of VI in process of expiration of an electric resource is revealed at lightning pulse test. It occurs owing to reduction of Dielectric Strength of system “case-shield” owing to metallization of a part of an internal insulation surface of VI case with products of contact erosion. Metallization increases with reduction of switching resource. Dielectric Strength of an inter-contact gap with its sufficient length does not provide Dielectric Strength of VI. The original shielding system providing preservation of Dielectric Strength of VI up to expiration of an electric resource is developed and offered.
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Dielectric Strength of two series connected vacuum interrupters
2008 23rd International Symposium on Discharges and Electrical Insulation in Vacuum, 2008Co-Authors: D. F. Alferov, L.a. Ryl'skaya, A. A. Pertsev, G. S. Belkin, Yu. G. Romochkin, V. A. SidorovAbstract:Statistical Dielectric Strength tests of high-voltage vacuum interrupters and series connected vacuum interrupters have been conducted. It has been shown that the experimental distribution of the vacuum interrupter breakdown voltage can be described quite well with the two-parameter Weilbull distribution. The experimental breakdown voltage distribution of the series connected vacuum interrupters has been compared with the calculated distribution functions. The calculations were based on the earlier proposed mathematical model of the series connected vacuum gaps breakdown. Experimentally established functions of the breakdown voltage distribution in each gap are used in this model. Also, the Dielectric Strength characteristics of series connected vacuum interrupters with of the unequal voltage division between them have been studied.
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Dielectric Strength of series connected vacuum gaps
IEEE Transactions on Dielectrics and Electrical Insulation, 2006Co-Authors: V. A. Sidorov, D. F. Alferov, E.d. AlferovaAbstract:A simple procedure to obtain an analytical equation for the distribution function of breakdown voltage in devices containing an arbitrary number of identical elements in series is proposed. The obtained results make possible to analyze an influence of static properties of the elements and their number on the Dielectric Strength of a device as a whole. The probability of the breakdown of the switching device is calculated using the empirical distribution functions of breakdown voltages of each TVS. The Weibull plots are used to analyze the breakdown test results. The measurement of the Dielectric Strength performed for AC and DC devices shows a good agreement with the calculated data.
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On statistics of Dielectric Strength of triggered vacuum switches
20th International Symposium on Discharges and Electrical Insulation in Vacuum, 2002Co-Authors: D. F. Alferov, V.a. Nevrovsky, V. A. SidorovAbstract:The paper deals with experimental tests of Dielectric Strength of triggered vacuum switches (TVS). The Dielectric Strength was measured applying AC high voltage to a switch after several commutations of current in the TVS. Two approaches to determine a breakdown probability curve were used in the tests. Taking into account practical considerations, the main body of experimental results was obtained at the low probability end of the curve.
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Dielectric Strength of triggered vacuum switches with six-gap electrode system
Proceedings ISDEIV. 18th International Symposium on Discharges and Electrical Insulation in Vacuum (Cat. No.98CH36073), 1998Co-Authors: V. A. Sidorov, D. F. Alferov, N.i. KorobovaAbstract:Switching conditions influence on Dielectric Strength of internal insulation of high-current triggered vacuum switches with a trapezoidal rod electrode system is investigated. Investigations were carried out for two switching modes. In the first mode electrode erosion occurs mainly in a vapour phase when the electrode's surface remains smooth enough after switching. In the other switching mode, drop phase of electrodes erosion prevailed and considerable electrode surface damage took place. It follows from experimental data statistical processing that breakdown voltage distribution is described satisfactorily with the Weibull distribution law. The influence of gap and electrode material on Dielectric Strength of triggered vacuum switches is considered.
D. F. Alferov - One of the best experts on this subject based on the ideXlab platform.
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Change of Dielectric Strength of vacuum interrupters in process of life-time degradation
Proceedings - International Symposium on Discharges and Electrical Insulation in Vacuum ISDEIV, 2010Co-Authors: D. F. Alferov, L.a. Ryl'skaya, A. A. Pertsev, V. A. SidorovAbstract:60 kV vacuum interrupters (VI) for 110 kV circuit-breakers are investigated. Reduction of Dielectric Strength of VI in process of expiration of an electric resource is revealed at lightning pulse test. It occurs owing to reduction of Dielectric Strength of system “case-shield” owing to metallization of a part of an internal insulation surface of VI case with products of contact erosion. Metallization increases with reduction of switching resource. Dielectric Strength of an inter-contact gap with its sufficient length does not provide Dielectric Strength of VI. The original shielding system providing preservation of Dielectric Strength of VI up to expiration of an electric resource is developed and offered.
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Dielectric Strength of two series connected vacuum interrupters
2008 23rd International Symposium on Discharges and Electrical Insulation in Vacuum, 2008Co-Authors: D. F. Alferov, L.a. Ryl'skaya, A. A. Pertsev, G. S. Belkin, Yu. G. Romochkin, V. A. SidorovAbstract:Statistical Dielectric Strength tests of high-voltage vacuum interrupters and series connected vacuum interrupters have been conducted. It has been shown that the experimental distribution of the vacuum interrupter breakdown voltage can be described quite well with the two-parameter Weilbull distribution. The experimental breakdown voltage distribution of the series connected vacuum interrupters has been compared with the calculated distribution functions. The calculations were based on the earlier proposed mathematical model of the series connected vacuum gaps breakdown. Experimentally established functions of the breakdown voltage distribution in each gap are used in this model. Also, the Dielectric Strength characteristics of series connected vacuum interrupters with of the unequal voltage division between them have been studied.
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Dielectric Strength of series connected vacuum gaps
IEEE Transactions on Dielectrics and Electrical Insulation, 2006Co-Authors: V. A. Sidorov, D. F. Alferov, E.d. AlferovaAbstract:A simple procedure to obtain an analytical equation for the distribution function of breakdown voltage in devices containing an arbitrary number of identical elements in series is proposed. The obtained results make possible to analyze an influence of static properties of the elements and their number on the Dielectric Strength of a device as a whole. The probability of the breakdown of the switching device is calculated using the empirical distribution functions of breakdown voltages of each TVS. The Weibull plots are used to analyze the breakdown test results. The measurement of the Dielectric Strength performed for AC and DC devices shows a good agreement with the calculated data.
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On statistics of Dielectric Strength of triggered vacuum switches
20th International Symposium on Discharges and Electrical Insulation in Vacuum, 2002Co-Authors: D. F. Alferov, V.a. Nevrovsky, V. A. SidorovAbstract:The paper deals with experimental tests of Dielectric Strength of triggered vacuum switches (TVS). The Dielectric Strength was measured applying AC high voltage to a switch after several commutations of current in the TVS. Two approaches to determine a breakdown probability curve were used in the tests. Taking into account practical considerations, the main body of experimental results was obtained at the low probability end of the curve.
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Dielectric Strength of triggered vacuum switches with six-gap electrode system
Proceedings ISDEIV. 18th International Symposium on Discharges and Electrical Insulation in Vacuum (Cat. No.98CH36073), 1998Co-Authors: V. A. Sidorov, D. F. Alferov, N.i. KorobovaAbstract:Switching conditions influence on Dielectric Strength of internal insulation of high-current triggered vacuum switches with a trapezoidal rod electrode system is investigated. Investigations were carried out for two switching modes. In the first mode electrode erosion occurs mainly in a vapour phase when the electrode's surface remains smooth enough after switching. In the other switching mode, drop phase of electrodes erosion prevailed and considerable electrode surface damage took place. It follows from experimental data statistical processing that breakdown voltage distribution is described satisfactorily with the Weibull distribution law. The influence of gap and electrode material on Dielectric Strength of triggered vacuum switches is considered.
Rakesh Kumar - One of the best experts on this subject based on the ideXlab platform.
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Dielectric Strength of parylene HT
Journal of Applied Physics, 2014Co-Authors: Sombel Diaham, M. Bechara, Marie-laure Locatelli, Rabih Khazaka, Christophe Tenailleau, Rakesh KumarAbstract:The Dielectric Strength of parylene HT (PA-HT) films was studied at room temperature in a wide thickness range from 500 nm to 50 μm and was correlated with nano- and microstructure analyses. X-ray diffraction and polarized optical microscopy have revealed an enhancement of crystallization and spherulites development, respectively, with increasing the material thickness (d). Moreover, a critical thickness dC (between 5 and 10 μm) is identified corresponding to the beginning of spherulite developments in the films. Two distinct behaviors of the Dielectric Strength (FB ) appear in the thickness range. For d ≥ dC , PA-HT films exhibit a decrease in the breakdown field following a negative slope (FB ∼ d −0.4), while for d
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Dielectric Strength of parylene ht
Journal of Applied Physics, 2014Co-Authors: Sombel Diaham, M. Bechara, Marie-laure Locatelli, Rabih Khazaka, Christophe Tenailleau, Rakesh KumarAbstract:The Dielectric Strength of parylene HT (PA-HT) films was studied at room temperature in a wide thickness range from 500 nm to 50 μm and was correlated with nano- and microstructure analyses. X-ray diffraction and polarized optical microscopy have revealed an enhancement of crystallization and spherulites development, respectively, with increasing the material thickness (d). Moreover, a critical thickness dC (between 5 and 10 μm) is identified corresponding to the beginning of spherulite developments in the films. Two distinct behaviors of the Dielectric Strength (FB ) appear in the thickness range. For d ≥ dC , PA-HT films exhibit a decrease in the breakdown field following a negative slope (FB ∼ d −0.4), while for d < dC , it increases with increasing the thickness (FB ∼ d 0.3). An optimal thickness doptim ∼ 5 μm corresponding to a maximum Dielectric Strength (FB ∼ 10 MV/cm) is obtained. A model of spherulite development in PA-HT films with increasing the thickness is proposed. The decrease in FB above dC is explained by the spherulites development, whereas its increase below dC is induced by the crystallites growth. An annealing of the material shows both an enhancement of FB and an increase of the crystallites and spherulites dimensions, whatever the thickness. The breakdown field becomes thickness-independent below dC showing a strong influence of the nano-scale structural parameters. On the contrary, both nano- and micro-scale structural parameters appear as influent on FB for d ≥ dC.
R Schorner - One of the best experts on this subject based on the ideXlab platform.
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Dielectric Strength of thermal oxides on 6h sic and 4h sic
Applied Physics Letters, 1994Co-Authors: P Friedrichs, E P Burte, R SchornerAbstract:This work reports on the Dielectric Strength of oxide layers formed by thermal oxidation of silicon carbide (SiC). SiC epilayers grown homoepitaxially on the silicon face of 6H‐SiC and 4H‐SiC substrates were oxidized in dry or wet ambient at 1100 °C. The Dielectric Strength was investigated using metal–oxide‐semiconductor capacitors and was found to be tightly bound to 10 MV/cm for oxide thicknesses around 65 nm and independent of the SiC polytype and substrate doping. Considering the current‐voltage characteristics in the prebreakdown region, dry oxides exhibit superior quality. Fowler–Nordheim tunneling was identified as the limiting current mechanism in the dry oxides. The corresponding barrier heights between the two SiC polytypes and thermal silicon dioxide were determined.
Sombel Diaham - One of the best experts on this subject based on the ideXlab platform.
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DC Dielectric Strength of epoxy/Si 3 N 4 nanocomposites
2016 IEEE International Conference on Dielectrics (ICD), 2016Co-Authors: Sombel Diaham, E. Pizzutilo, M.-l. LocatelliAbstract:The influence of silicon nitride (Si 3 N 4 ) nanoparticles is studied on the DC Dielectric Strength of an epoxy-based nanocomposite. Si 3 N 4 nanofillers are interesting due to good both electrical insulation and thermal conduction properties. To obtain an increase in the breakdown field, the manufacturing process parameters are optimized to reduce the presence of aggregates in the final nanocomposites. The influence of a surface functionalization of the nanofillers in ethanol solvent was studied based on both surfactant and coupling agent treatments. An optimized electrophoretic stability of the Si 3 N 4 nanofillers was obtained in ethanol for acid pH. The epoxy/Si 3 N 4 (1 vol.%) nanocomposites show an improvement of the Dielectric Strength compared to neat epoxy. Surface coupling agent treatment of Si 3 N 4 nanofillers shows an additional improvement of the Dielectric Strength.
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Dielectric Strength of parylene HT
Journal of Applied Physics, 2014Co-Authors: Sombel Diaham, M. Bechara, Marie-laure Locatelli, Rabih Khazaka, Christophe Tenailleau, Rakesh KumarAbstract:The Dielectric Strength of parylene HT (PA-HT) films was studied at room temperature in a wide thickness range from 500 nm to 50 μm and was correlated with nano- and microstructure analyses. X-ray diffraction and polarized optical microscopy have revealed an enhancement of crystallization and spherulites development, respectively, with increasing the material thickness (d). Moreover, a critical thickness dC (between 5 and 10 μm) is identified corresponding to the beginning of spherulite developments in the films. Two distinct behaviors of the Dielectric Strength (FB ) appear in the thickness range. For d ≥ dC , PA-HT films exhibit a decrease in the breakdown field following a negative slope (FB ∼ d −0.4), while for d
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Dielectric Strength of parylene ht
Journal of Applied Physics, 2014Co-Authors: Sombel Diaham, M. Bechara, Marie-laure Locatelli, Rabih Khazaka, Christophe Tenailleau, Rakesh KumarAbstract:The Dielectric Strength of parylene HT (PA-HT) films was studied at room temperature in a wide thickness range from 500 nm to 50 μm and was correlated with nano- and microstructure analyses. X-ray diffraction and polarized optical microscopy have revealed an enhancement of crystallization and spherulites development, respectively, with increasing the material thickness (d). Moreover, a critical thickness dC (between 5 and 10 μm) is identified corresponding to the beginning of spherulite developments in the films. Two distinct behaviors of the Dielectric Strength (FB ) appear in the thickness range. For d ≥ dC , PA-HT films exhibit a decrease in the breakdown field following a negative slope (FB ∼ d −0.4), while for d < dC , it increases with increasing the thickness (FB ∼ d 0.3). An optimal thickness doptim ∼ 5 μm corresponding to a maximum Dielectric Strength (FB ∼ 10 MV/cm) is obtained. A model of spherulite development in PA-HT films with increasing the thickness is proposed. The decrease in FB above dC is explained by the spherulites development, whereas its increase below dC is induced by the crystallites growth. An annealing of the material shows both an enhancement of FB and an increase of the crystallites and spherulites dimensions, whatever the thickness. The breakdown field becomes thickness-independent below dC showing a strong influence of the nano-scale structural parameters. On the contrary, both nano- and micro-scale structural parameters appear as influent on FB for d ≥ dC.