2019 5th International Conference on Electric Power Equipment - Switching Technology (ICEPE-ST)最新文献

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Discharge Path Measurement of A Vacuum Interrupter with Fixed Break after Suffering High Inrush Current 高涌流冲击后固定开断真空灭流器放电路径的测量
Jian’gang Ding, Zhiyuan Liu, Yingsan Geng, Jianhua Wang, X. Yao, Hui Ma, Jiali Chen, Guoqin Li, Xue Liu, W. Shi, Xiaojun Wang, Kai Liu
{"title":"Discharge Path Measurement of A Vacuum Interrupter with Fixed Break after Suffering High Inrush Current","authors":"Jian’gang Ding, Zhiyuan Liu, Yingsan Geng, Jianhua Wang, X. Yao, Hui Ma, Jiali Chen, Guoqin Li, Xue Liu, W. Shi, Xiaojun Wang, Kai Liu","doi":"10.1109/ICEPE-ST.2019.8928720","DOIUrl":"https://doi.org/10.1109/ICEPE-ST.2019.8928720","url":null,"abstract":"Discharge path determination of a vacuum interrupter is important for development to higher voltage levels, but no direct measurement has been carried out on a VI. The objective of this paper is to directly measure breakdown path of a VI. A VI with fixed breaks were designed and used in the experiment. The fixed break was composed a pair of fixed shields and in parallel with the movable contact gap. One of the shield was fixed to the end cover while the other one was fixed between two porcelain shell, and could be connected to the moving rod out of the VI. By measuring current of a shield and a contact separately, breakdown path could be deduced. The tested VI was firstly conditioned to a statured state with the 50% impulse breakdown voltage U50=221kV. Then it suffered the inrush current 30 times. Next, standard lighting impulse voltage was applied by an up-and-down method. Experimental results showed that breakdown path could be measured on both the contacts and the fixed shields, and three obvious stages could be found during lightening impulse voltage application. In stage □, breakdowns mainly occurred on the contacts as breakdown voltage raised quickly. In stage □, breakdowns occurred alternately on the contacts and the fixed shields and the breakdown voltage raised much slower. In stage □, breakdowns mainly occurred on the fixed shields and the breakdown voltage reaches the saturation region with the 50% impulse breakdown voltage U50=183kV.","PeriodicalId":392306,"journal":{"name":"2019 5th International Conference on Electric Power Equipment - Switching Technology (ICEPE-ST)","volume":"3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133295490","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
Particle-In-Cell Monte Carlo Collision Simulation of the Breakdown Initiating Process in Vacuum 真空击穿起始过程的粒子池内蒙特卡罗碰撞模拟
H. Ejiri, Takashi Fujii, A. Kumada, K. Hidaka
{"title":"Particle-In-Cell Monte Carlo Collision Simulation of the Breakdown Initiating Process in Vacuum","authors":"H. Ejiri, Takashi Fujii, A. Kumada, K. Hidaka","doi":"10.1109/ICEPE-ST.2019.8928681","DOIUrl":"https://doi.org/10.1109/ICEPE-ST.2019.8928681","url":null,"abstract":"The initiating process of vacuum breakdown is still unknown despite the efforts of many researchers in the long history of vacuum insulation. This paper reports the results of Particle-In-Cell Monte Carlo Collision simulation in the vicinity of an emitter of the electrons and the neutrals on the cathode. The radius of the emitter re, the temperature of the emitter T, product of macroscopic electric field and electric field enhancement factor β•Emac, and the electric field enhancement factor β itself are used as the parameters. It turns out that the current increased in some combinations of the parameters as the result of positive feedback of field emission, ion generation, electric field enhancement, increase in field emission electrons. All parameters affect whether the current increase or not. The radius of the emitter re is a key parameter to determine the occurrence of the current increase. This is because the density of the neutrals at the point where ionization occurs becomes larger with re.","PeriodicalId":392306,"journal":{"name":"2019 5th International Conference on Electric Power Equipment - Switching Technology (ICEPE-ST)","volume":"60 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132565508","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
The Analysis of Low-Voltage DC Arc behavior on Three Interrupting Phases Based on AC Black-box Arc model 基于交流黑箱电弧模型的低压直流电弧三相断流行为分析
Kyu-Hoon Park, Ho-Yun Lee, Bang-wook Lee
{"title":"The Analysis of Low-Voltage DC Arc behavior on Three Interrupting Phases Based on AC Black-box Arc model","authors":"Kyu-Hoon Park, Ho-Yun Lee, Bang-wook Lee","doi":"10.1109/ICEPE-ST.2019.8928789","DOIUrl":"https://doi.org/10.1109/ICEPE-ST.2019.8928789","url":null,"abstract":"Among many low voltage power electrical devices, Low-voltage (LV) dc circuit breaker (DCCB) is one of the most essential components and is widely used to protect the overall LV dc distribution system. Therefore, many research institutes and manufacturers have been concentrating a lot of research and interest in LV DCCB in recent years. LV dc arc simulation modeling technique using computational methods is being studied. However, dc arc modeling technique using only finite element method is studied among various modeling methods, and there are no existing researches of dynamic arc-circuit interaction analysis using a black-box model. In this paper, LV dc arc is modeled by using the proposed black-box model as the ac arc modeling technique. The existing LV DCCB has air arc characteristics according to the interrupting topology, and the corresponding LV dc arc interrupting phases can be divided into arc commutation, arc motion, and arc splitting. Arc modeling was performed on three interrupting phases, based on the typical waveform of a LV dc arc and actual experimental data. The black-box model uses the schwarz model, which is known to be best suited for representing the small current and large current regions of the arc. As a result, the applicability of the dc arc was evaluated using the existing ac black-box model, and the behavior of the dc arc for each interrupting phase was described.","PeriodicalId":392306,"journal":{"name":"2019 5th International Conference on Electric Power Equipment - Switching Technology (ICEPE-ST)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131330405","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
Current Sharing Characteristics Study of Parallel IGCTs Module in a DC Circuit Breaker 直流断路器并联igct模块的共流特性研究
Yife Wu, Zhihui Zhang, Wentao Liu, Yi Wu, M. Rong, Fei Yang, Nan Shi, Lin-cui Zeng
{"title":"Current Sharing Characteristics Study of Parallel IGCTs Module in a DC Circuit Breaker","authors":"Yife Wu, Zhihui Zhang, Wentao Liu, Yi Wu, M. Rong, Fei Yang, Nan Shi, Lin-cui Zeng","doi":"10.1109/ICEPE-ST.2019.8928760","DOIUrl":"https://doi.org/10.1109/ICEPE-ST.2019.8928760","url":null,"abstract":"Hybrid DC circuit breaker (HDCCB) has the advantages of low on-state loss and fast breaking speed, so it is an important development direction in the field of DC breaking. The integrated gate commutated thyristor (IGCT) has the advantages of low on-state voltage, fast turn-off speed and strong anti-surge capability, so it is suitable for power electronic switch which is the core breaking component of the HDCCB. In this paper, a parallel IGCTs module as the power electronic switch in a HDCCB is designed. The fundamental principle of current sharing of parallel IGCTs is analyzed. A test platform is set up to investigate the influencing factors of current sharing of parallel IGCTs, including electrical characteristics of IGCTs, clamping force, current rise rate and current amplitude. Finally, the conclusion of the current sharing characteristics of parallel IGCTs under different factors is obtained by tests.","PeriodicalId":392306,"journal":{"name":"2019 5th International Conference on Electric Power Equipment - Switching Technology (ICEPE-ST)","volume":"23 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128658955","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
Two Dimensional Distribution Diagnostic of Copper Vapor in a Vacuum Arc by Laser-induced Fluorescence 激光诱导荧光法诊断真空电弧中铜蒸气的二维分布
Jiankun Liu, Ziru Zha, Zhenxing Wang, Liqiong Sun, Jianhua Wang, Yingsan Geng, Zhiyuan Liu
{"title":"Two Dimensional Distribution Diagnostic of Copper Vapor in a Vacuum Arc by Laser-induced Fluorescence","authors":"Jiankun Liu, Ziru Zha, Zhenxing Wang, Liqiong Sun, Jianhua Wang, Yingsan Geng, Zhiyuan Liu","doi":"10.1109/ICEPE-ST.2019.8928887","DOIUrl":"https://doi.org/10.1109/ICEPE-ST.2019.8928887","url":null,"abstract":"It is important to obtain the information on the neutral metallic vapor during the arcing period for a better understanding of vacuum arc interruption process. In this work, the objective is to experimentally study the two dimensional distribution of copper vapor during arcing. A reverse current was injected at specific time points to force the 45 Hz sinusoidal arc current to be extinguished in a short time, avoiding the interference of intensive arc self-radiation. Meanwhile, the plane laser-induced fluorescence (PLIF) using a pulse laser with a central wavelength at 324.8 nm was adopted to excite the metallic vapor, and a iCCD camera recorded the distribution of the vapor from the induced fluorescence. In the experiments, a pair of cup-shaped axial magnetic field (AMF) contacts were used. The material was CuCr50 and the peak amplitude of the arc current was 3 kA. It is found that the peak value of the metallic vapor density occurred at about 8 ms while the current peak occurred approximate 3 ms in advance, and the highest density value can achieve up to 2.3×1020m-3. It is also found that the metallic vapor mainly accumulated on the anode surface under AMF during the arcing period, which became obvious when the current begins to drop.","PeriodicalId":392306,"journal":{"name":"2019 5th International Conference on Electric Power Equipment - Switching Technology (ICEPE-ST)","volume":"18 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128737249","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
High Voltage Gradient ZnO-Based Varistors from ZnO Nano-powders for DC Current Switching Application 用于直流开关的ZnO纳米粉体高电压梯度ZnO基压敏电阻
Xiangjun Zeng, Wenfeng Liu, Lei Zhang, Zhi Wang, Shengtao Li, Fuzeng Zhang, Tingting Wang, Y. Liao
{"title":"High Voltage Gradient ZnO-Based Varistors from ZnO Nano-powders for DC Current Switching Application","authors":"Xiangjun Zeng, Wenfeng Liu, Lei Zhang, Zhi Wang, Shengtao Li, Fuzeng Zhang, Tingting Wang, Y. Liao","doi":"10.1109/ICEPE-ST.2019.8928903","DOIUrl":"https://doi.org/10.1109/ICEPE-ST.2019.8928903","url":null,"abstract":"With the increasing demand for high voltage level and miniaturization of extensive power equipment, ZnO ceramics, as key energy absorption elements in DC current breakers, are required to possess even higher voltage gradient. In this paper, nano-sized starting materials ZnO powders were employed to achieve the high voltage gradient. The effect of sintering temperature on the microstructural evolution and electrical characteristics of these obtained varistors were investigated by means of XRD, SEM, J-E measurement and dielectric spectroscopy. Experimental results showed that the fine sized powder could contribute to the high voltage gradient; the optimized sintering temperature for nano-sized starting ZnO powders was 1050°C. The obtained ZnO ceramics sintered at 1050°C exhibited high voltage gradient of 805 V/mm, which was over 4-times than that of the commercial varistors. Meanwhile such ceramics possessed large nonlinear coefficient of 30 and the low leakage current of 1.38 μA/cm2. Such improved performance may could be ascribed to the decreased grain size, the enhanced microstructure homogeneity and the well-formed double Schottky-barrier. Such result indicated the nano-sized ZnO powders as the starting raw material may benefit the high performance of ZnO varistors and is a promising solution to the miniaturization of DC current breakers.","PeriodicalId":392306,"journal":{"name":"2019 5th International Conference on Electric Power Equipment - Switching Technology (ICEPE-ST)","volume":"5 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134373765","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
Characteristics of Field Emission Phenomena of Single Micro-protrusion on Vacuum Gap Cathode Based on Fractal Theory 基于分形理论的真空间隙阴极单微突场发射现象特征
Yingyao Zhang, Shaojie Chen, Manman Ma, He Yang, Biao Hu, Xiaojun Wang
{"title":"Characteristics of Field Emission Phenomena of Single Micro-protrusion on Vacuum Gap Cathode Based on Fractal Theory","authors":"Yingyao Zhang, Shaojie Chen, Manman Ma, He Yang, Biao Hu, Xiaojun Wang","doi":"10.1109/ICEPE-ST.2019.8928803","DOIUrl":"https://doi.org/10.1109/ICEPE-ST.2019.8928803","url":null,"abstract":"It is well known that a seemingly smooth electrode surface is anything but smooth when observed at a microscopic level. In fact, there are a great amount of micro-protrusions on the electrode surface in vacuum gap, which will enhance the local electrical field on the tip dramatically. However, the classical Fowler-Nordheim equation for the planar surfaces is still being used to analyze the field emission phenomenon despite of the micro-protrusions’ existence. The objective of this paper is to investigate the characteristics of the field emission phenomena on the tip of a single micro-protrusion based on the fractal theory. In addition, the thermal instability of a single micro-protrusion will be taken into account, which is caused by the thermal effect of the field emission current and the heat conduction inside the micro-protrusion. The research of this paper will look deep into the mechanism of the formation of metal vapor in the vacuum gap that will do great harm to the vacuum insulation characteristics.","PeriodicalId":392306,"journal":{"name":"2019 5th International Conference on Electric Power Equipment - Switching Technology (ICEPE-ST)","volume":"140 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133645116","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
Theoretical Determination of Total Electron-impact Ionization Cross Sections of Dichlorodifluoromethane (R12) and Tetrafluoroethane (R134) 二氯二氟甲烷(R12)和四氟乙烷(R134)总电子冲击电离截面的理论测定
F. Tang, Jiayu Xiong, Boya Zhang, Qishen Lv, Xingwen Li
{"title":"Theoretical Determination of Total Electron-impact Ionization Cross Sections of Dichlorodifluoromethane (R12) and Tetrafluoroethane (R134)","authors":"F. Tang, Jiayu Xiong, Boya Zhang, Qishen Lv, Xingwen Li","doi":"10.1109/ICEPE-ST.2019.8928811","DOIUrl":"https://doi.org/10.1109/ICEPE-ST.2019.8928811","url":null,"abstract":"SF6 has been employed as insulation and arc-quenching medium in high voltage apparatus since the 1960s. However, due to the high global warming potential (GWP) of SF6 gas, the alternative to SF6 is required. R12 and R134 gases offer good dielectric properties to be good replacements of SF6 as insulation medium considering the environmental concerns. In order to further investigate the ionization processes in those gases, the electron-impact ionization cross sections are calculated by Deutsch-Märk (DM) and its modified methods. The molecular structures and the molecular orbital compositions of R12 and R134 were determined by ab initio calculation. The results give important reference for the two SF6 substitute gases.","PeriodicalId":392306,"journal":{"name":"2019 5th International Conference on Electric Power Equipment - Switching Technology (ICEPE-ST)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132930294","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
Research on Intermediate-frequency Vacuum Arc and Voltage Characteristics of Sinusoidal Curved Contact 中频真空电弧及正弦曲线接触电压特性研究
Ziang Tong, Jianwen Wu, Miao Cheng, Yuanchun Jiang, Bowen Jia
{"title":"Research on Intermediate-frequency Vacuum Arc and Voltage Characteristics of Sinusoidal Curved Contact","authors":"Ziang Tong, Jianwen Wu, Miao Cheng, Yuanchun Jiang, Bowen Jia","doi":"10.1109/ICEPE-ST.2019.8928846","DOIUrl":"https://doi.org/10.1109/ICEPE-ST.2019.8928846","url":null,"abstract":"In this paper, a new type of contact structure for vacuum interrupters, sinusoidal surface contact, is proposed, and its vacuum arc characteristics at intermediate frequency are studied. Then the arc mode evolution, arc voltage characteristics, arc energy, breaking performance, the ablation of anode contact and arc product condensation ability of the sinusoidal curved contact and the plate contact with the same contact diameter (41mm) and the material are compared and analyzed under small open distance. The correlations between the arc energy and the amplitude and frequency of the current and the influence of the arc energy on the breaking capacity are achieved. The results showed that the sinusoidal curved contact has strong application potential by its lower arc energy, lower arc voltage noise and arc voltage peak, lighter ablation on the surface of the anode contact and splash, stronger breaking capacity.","PeriodicalId":392306,"journal":{"name":"2019 5th International Conference on Electric Power Equipment - Switching Technology (ICEPE-ST)","volume":"29 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122171849","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
3D Simulation of Air Arc in the Molded Case Circuit Breaker 塑壳断路器空气电弧的三维模拟
Keewon Kim, H. Joo, Chae Yoon Bae, Jongung Choi, Young Geun Kim
{"title":"3D Simulation of Air Arc in the Molded Case Circuit Breaker","authors":"Keewon Kim, H. Joo, Chae Yoon Bae, Jongung Choi, Young Geun Kim","doi":"10.1109/ICEPE-ST.2019.8928799","DOIUrl":"https://doi.org/10.1109/ICEPE-ST.2019.8928799","url":null,"abstract":"In low voltage switch gears, the arc voltage is a very important factor that decides the interruption performance. There are several ways to increase the arc voltage, like increasing the number of the arc chutes or the distance between the contacts. During the interruption, the separation of the contacts plays an important role in different kinds of switch gears since the arc motion or the arc elongation will be effected. However, the simulation of the arc behavior in low voltage switch gears is quite difficult due to the fact that: the 3D simulation makes the computation quite expensive; the existence of the arc chutes makes the calculation non-linear; the structure of some switch gears could be quite complicated. Therefore, the movement of the contact was neglected for simplicity. In fact, the movement of the contact could increase the arc length and then decide the arc behavior. In reverse, the arc current will be changed during the interruption and the Lorentz force will then influence the movement of the contact. It is necessary to consider this phenomenon to make the arc simulation more accurate and universal. In this work, low voltage arc plasma simulation in 3D with contact opening process has been established. Both the sheath and nonlinear magnetic material are taken into consideration. Calculation is based on magneto-hydrodynamic arc model, a method for coupling different software to separately calculate fluid and electromagnetic field has been developed to fulfill the requirements above. Furthermore, a low voltage circuit breaker has been experimented to compare with the simulation from U-I characteristics. The simulation results suggest that this method applied in arc simulation performs better in converging and accuracy.","PeriodicalId":392306,"journal":{"name":"2019 5th International Conference on Electric Power Equipment - Switching Technology (ICEPE-ST)","volume":"62 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130201161","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
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