2012 25th International Symposium on Discharges and Electrical Insulation in Vacuum (ISDEIV)最新文献

Low-energy, high-current electron beams for material surface treatment 用于材料表面处理的低能量、大电流电子束

2012 25th International Symposium on Discharges and Electrical Insulation in Vacuum (ISDEIV) Pub Date : 2014-06-01 DOI: 10.1109/IVESC.2014.6892051

G. Ozur

引用次数: 2

The influence of lagged axial magnetic field on the distribution of cathodes spots in current-zero stage of vacuum arc 轴向滞后磁场对真空电弧零电流阶段阴极斑点分布的影响

2012 25th International Symposium on Discharges and Electrical Insulation in Vacuum (ISDEIV) Pub Date : 2012-09-01 DOI: 10.1109/DEIV.2012.6412510

Xiaochuan Song, Z. Shi, S. Jia, Lijun Wang, Yingkui Zhang

{"title":"The influence of lagged axial magnetic field on the distribution of cathodes spots in current-zero stage of vacuum arc","authors":"Xiaochuan Song, Z. Shi, S. Jia, Lijun Wang, Yingkui Zhang","doi":"10.1109/DEIV.2012.6412510","DOIUrl":"https://doi.org/10.1109/DEIV.2012.6412510","url":null,"abstract":"The influence of lagged axial magnetic field (AMF) due to eddy current induced in contacts system on the distribution of cathode spots (CSs) in current-zero stage of vacuum arc with different current falling rates was investigated experimentally. Experiments were conducted with cup-shaped AMF contacts in a demountable vacuum chamber. The characteristic of CSs distribution of triggered vacuum arc in current-zero stage with arc current frequency of 50Hz was investigated at first with the aid of a high-speed digital camera with an exposure time of 2 microseconds. Then the characteristic of CSs distribution with faster current falling rate, which was realized by injecting a countercurrent with frequency of 500Hz or 1kHz, was investigated. Moreover, the lagged AMF flux density in current-zero stage with different current falling rates was calculated by ANSYS. Research results showed that CSs located in the center of contact plate tended to extinguish earlier than those at periphery of contact plate in fast current-zero stage due to the stronger lagged AMF in contact center.","PeriodicalId":130964,"journal":{"name":"2012 25th International Symposium on Discharges and Electrical Insulation in Vacuum (ISDEIV)","volume":"41 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121803504","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}

引用次数: 2

Investigation of correlation between vacuum breakdown phenomena and field emission current during shunt capacitor switching 并联电容器开关过程中真空击穿现象与场发射电流的相关性研究

2012 25th International Symposium on Discharges and Electrical Insulation in Vacuum (ISDEIV) Pub Date : 2012-09-01 DOI: 10.1109/DEIV.2012.6412477

T. Donen, M. Tsukima, S. Sato, T. Yoshida

{"title":"Investigation of correlation between vacuum breakdown phenomena and field emission current during shunt capacitor switching","authors":"T. Donen, M. Tsukima, S. Sato, T. Yoshida","doi":"10.1109/DEIV.2012.6412477","DOIUrl":"https://doi.org/10.1109/DEIV.2012.6412477","url":null,"abstract":"In the case of interrupting capacitive loads, the most challenging problem for vacuum interrupters is to withstand recovery voltage during opening operation. In addition, the field enhancement factor of vacuum contacts is assumed to be high due to the damage of contacts caused by making the inrush current. In this paper, simulated shunt capacitor switching tests are carried out and the field emission current across the contact gap is measured to research the influence of the inrush current on the breakdown phenomena during opening operation. All breakdowns occur before the gap spacing reaches the maximum value and it is determined that there is a correlation between the electric field breakdown and the field emission current measured before the breakdowns. Furthermore, the found correlation is independent of the amplitude of the inrush current. The electric field breakdown is nearly invariant under the condition that the measured field emission current is constant regardless of the inrush current. However, the field emission current tends to be high in the presence of a large inrush current. The difference in the expected field emission current is believed to affect the electric field breakdown.","PeriodicalId":130964,"journal":{"name":"2012 25th International Symposium on Discharges and Electrical Insulation in Vacuum (ISDEIV)","volume":"105 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117216699","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}

引用次数: 6

Microscopic observation and analysis of field electron emission sites by using an Electron Emission Microscope and Auger Electron Spectrometer 利用电子发射显微镜和俄歇电子能谱仪对场电子发射部位进行了显微观察和分析

2012 25th International Symposium on Discharges and Electrical Insulation in Vacuum (ISDEIV) Pub Date : 2012-09-01 DOI: 10.1109/DEIV.2012.6412456

T. Kanai, Y. Yamano, S. Kobayashi, Y. Saito

{"title":"Microscopic observation and analysis of field electron emission sites by using an Electron Emission Microscope and Auger Electron Spectrometer","authors":"T. Kanai, Y. Yamano, S. Kobayashi, Y. Saito","doi":"10.1109/DEIV.2012.6412456","DOIUrl":"https://doi.org/10.1109/DEIV.2012.6412456","url":null,"abstract":"Field electron emission is recognized as one of important phenomena related to the occurrence of electrical breakdown in vacuum. In this paper, we investigated the distribution of field electron emission sites on a plane electrode before and after current conditioning procedure. The investigation was carried out by scanning the electrode to measure the emission current flowing through the pin-hole of the objective lens of Electron Emission Microscope. As a result, before current conditioning localized emission sites were found. Those emission sites and the current from the sites were unstable in the early stage of high voltage application. During current conditioning and electrode scanning, some of emission sites disappeared, while the others continued to flow current. Sometimes new emission sites appeared at the other points on the electrode surface. After the investigation of emission sites distribution, microscopic observation on some of emission sites were carried out by using the Electron Emission Microscope. Electron emission microscope enables simultaneous observations of field electron emission image and photo electron emission image. The observation revealed that field electron emission occurred at the foreign particles on the electrode surface, and only some of them became electron emission sites. To characterize the emission sites, we observed the absorption current image and analyzed the chemical composition of the emission sites by using an Auger Electron Spectrometer. Observation and analysis suggest that the foreign particle was a semiconducting or insulating material composed of carbon.","PeriodicalId":130964,"journal":{"name":"2012 25th International Symposium on Discharges and Electrical Insulation in Vacuum (ISDEIV)","volume":"77 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127292017","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}

引用次数: 0

Transient modeling and simulation of high current vacuum arc under different conditions 大电流真空电弧在不同工况下的瞬态建模与仿真

2012 25th International Symposium on Discharges and Electrical Insulation in Vacuum (ISDEIV) Pub Date : 2012-09-01 DOI: 10.1109/DEIV.2012.6412520

Lijun Wang, Ling Zhang, L. Hu, S. Jia, Xin Zhou, Haijing Wang, Z. Shi

{"title":"Transient modeling and simulation of high current vacuum arc under different conditions","authors":"Lijun Wang, Ling Zhang, L. Hu, S. Jia, Xin Zhou, Haijing Wang, Z. Shi","doi":"10.1109/DEIV.2012.6412520","DOIUrl":"https://doi.org/10.1109/DEIV.2012.6412520","url":null,"abstract":"In this paper, based on a two-dimensional (2D) transient magneto-hydrodynamic (MHD) model, HCVA under different interruption conditions was simulated and analyzed. The simulation results of power-frequency current show that the simulation results of the transient model are the same as those of the steady-state model, as the varying time of current is much longer than the relaxation time of plasma. This verified the correctness of previous conclusions of simulating power-frequency vacuum arc by steady-state model. For fast current drop process in DC interruption, simulation results show that higher frequency makes current drops faster and ion number density larger, besides, the density of residual plasma between electrodes at current-zero moment is higher, and interruption becomes more difficult. Finally, transient characteristics of high-frequency HCVA also was simulated and analyzed. Simulation results showed that plasma between electrodes was too slow to spread in the high-frequency condition, and the change of ion number density lagged behind the current change; the higher ion number density in the second 1/4 cycle weakens the Hall Effect, and leading to a more uniform distribution of current density.","PeriodicalId":130964,"journal":{"name":"2012 25th International Symposium on Discharges and Electrical Insulation in Vacuum (ISDEIV)","volume":"10 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125403980","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}

引用次数: 0

Pulsed generators on base of LTD stages with vacuum insulation in a secondary turn 二匝真空绝缘的有限级脉冲发生器

2012 25th International Symposium on Discharges and Electrical Insulation in Vacuum (ISDEIV) Pub Date : 2012-09-01 DOI: 10.1109/DEIV.2012.6412546

A. Kharlov, B. Kovalchuk, E. V. Kumpyak, A. Zherlitsyn

引用次数: 1

A high accurate sensor research and its application for VCBs' internal pressure on-line condition monitor vcb内压在线监测高精度传感器的研究与应用

2012 25th International Symposium on Discharges and Electrical Insulation in Vacuum (ISDEIV) Pub Date : 2012-09-01 DOI: 10.1109/DEIV.2012.6412559

Zhang Xin, Liu Xu-dong, Fan Xing-ming, Huang Zhi-chao, Fan Jian-rong, Liang Cong, Shi Wei-jian

{"title":"A high accurate sensor research and its application for VCBs' internal pressure on-line condition monitor","authors":"Zhang Xin, Liu Xu-dong, Fan Xing-ming, Huang Zhi-chao, Fan Jian-rong, Liang Cong, Shi Wei-jian","doi":"10.1109/DEIV.2012.6412559","DOIUrl":"https://doi.org/10.1109/DEIV.2012.6412559","url":null,"abstract":"To improve the intelligence and reliability of the vacuum circuit breakers in power gird, a high accurate smart system was designed for On-line condition monitor of vacuum interrupters inner pressure. Through the study of dielectric theory and exploration of the inherent laws of shield potential with different pressure in VIs, it shows that with the deterioration of internal pressure the AC component on shield potential increase while the pressure stays lower than 0.1Pa and the DC component appears when the pressure increases to 0.1Pa. The structure, size and installation location of the sensor were designed with reasonable calculation to detect the weak changing signal. To meet the requirements of sampling signal characteristics, digital filter was developed to eliminate noise interference, the processed signal shows good smoothness and linearity after filtered. Fast Fourier transform (FFT) method is adopted to extract the amplitude of AC component on the shield potential, and fitting the empirical formula is derived based on the offline curve of AC component increment and inner pressure of VIs. Applying the previous theoretical studies to actual 10kV VCB on-line condition monitoring system design, focus was placed on the AC component of shield potential in the monitor devices. The feasibility of the sensor and transformation algorithm was proved in the end of this research.","PeriodicalId":130964,"journal":{"name":"2012 25th International Symposium on Discharges and Electrical Insulation in Vacuum (ISDEIV)","volume":"128 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116381998","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}

引用次数: 3

Field emission from metal tips covered by ultra-thin films of Zirkonia energy spectra features and current-voltage curves 超薄氧化锆薄膜覆盖金属尖场发射的能谱特征和电流-电压曲线

2012 25th International Symposium on Discharges and Electrical Insulation in Vacuum (ISDEIV) Pub Date : 2012-09-01 DOI: 10.1109/DEIV.2012.6412590

I. S. Turmyshev, A. Murzakaev, O. Timoshenkova

{"title":"Field emission from metal tips covered by ultra-thin films of Zirkonia energy spectra features and current-voltage curves","authors":"I. S. Turmyshev, A. Murzakaev, O. Timoshenkova","doi":"10.1109/DEIV.2012.6412590","DOIUrl":"https://doi.org/10.1109/DEIV.2012.6412590","url":null,"abstract":"Thermofield emission cathodes based on ZrO2/W heterostructures are widely used as a point electron source nowadays. At present issue results of simultaneous study of Volt-Ampere characteristics (VACH) and energy spectra of such cathodes are discussed just under field emission terms. Firstly, needle shaped tungsten cathodes were coated by thin (~ 10 nm) film of ZrO2 by means of thermo-field diffusion methods under ultra high vacuum conditions. In this case the tungsten emitters were used as reference patterns and their characteristics were measured before the coating process. It is shown that VACH of coated emitters plotted in Fowler-Nordheim coordinates has non-linear character contrarily to “metallic” VACH. Such behavior of VACH may be attributed to complicated energy spectra obtained during VACH measurement and complex electronic structure of thin film. There are two peaks on the spectra plot with 3-5 eV distance between them depending on emission voltage. It is shown that energy spectra of coated cathodes may have fine structure. Finally, the work function of the coated cathodes is lower by 2 eV in comparison to pure W cathodes.","PeriodicalId":130964,"journal":{"name":"2012 25th International Symposium on Discharges and Electrical Insulation in Vacuum (ISDEIV)","volume":"6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114428831","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}

引用次数: 1

Concept of series connected vacuum interrupters 串联真空断路器的概念

2012 25th International Symposium on Discharges and Electrical Insulation in Vacuum (ISDEIV) Pub Date : 2012-09-01 DOI: 10.1109/DEIV.2012.6412569

S. Kulkarni, M. Hemachander, S. A. Kumar, L. Andrews, V. Acharya, C. Maheswaran, S. Rayudu

引用次数: 6

Investigation of the high current stages in pseudospark discharge 假火花放电大电流级的研究

2012 25th International Symposium on Discharges and Electrical Insulation in Vacuum (ISDEIV) Pub Date : 2012-09-01 DOI: 10.1109/DEIV.2012.6412459

Y. Korolev, O. B. Frants, N. Landl, V. Kasyanov, A. Bolotov, I. A. Shemyakin

引用次数: 0