Pub Date : 2016-09-01DOI: 10.1109/DEIV.2016.7748757
A. Murzakaev
The present paper reports an experimental study of the erosion rate of pulsed arcs in vacuum under the influence of surface conditions (contaminants and clean), and ambient gases (argon, nitrogen with high purity introduced with pressures 600 Torr) with cold cathodes. Erosion rates have been studied of wires cathodes from Au, Ag, Cu, W prepared by heating less then melting temperature prior to arcing. Such surfaces may be sufficiently clean also without preceding erosion. In both systems the ion current streaming was measured by a biased collector. It appears that the erosion rates are not changed by outer influences background gas. The discrepancy between the ion collection and weighing methods clearly points to the contribution of macroparticles to cathode erosion. It has been shown that macroparticle mass losses are indeed important. Experimental results show that the mass of cathode material removed by the macroparticles flux is greater than the mass of cathode material leaving in form of ions. Besides ion current measurements also used the weighing method to determine the total erosion rate of cathode materials. From the analysis of the erosion rate as a function of charge transferred by the vacuum arc and arc in gases were concluded that the total erosion rate approaches the ion erosion rate if the charge transferred by the arc is small. The dependence of the ion current from vacuum arc current is in linear relation. The approximate independence of arc current is consistent with findings that increasing the arc current leads to an increase in the number of emission centers rather than changing the character of these centers.
{"title":"Erosion rate in a vacuum arc and in a gas arc at threshold currents","authors":"A. Murzakaev","doi":"10.1109/DEIV.2016.7748757","DOIUrl":"https://doi.org/10.1109/DEIV.2016.7748757","url":null,"abstract":"The present paper reports an experimental study of the erosion rate of pulsed arcs in vacuum under the influence of surface conditions (contaminants and clean), and ambient gases (argon, nitrogen with high purity introduced with pressures 600 Torr) with cold cathodes. Erosion rates have been studied of wires cathodes from Au, Ag, Cu, W prepared by heating less then melting temperature prior to arcing. Such surfaces may be sufficiently clean also without preceding erosion. In both systems the ion current streaming was measured by a biased collector. It appears that the erosion rates are not changed by outer influences background gas. The discrepancy between the ion collection and weighing methods clearly points to the contribution of macroparticles to cathode erosion. It has been shown that macroparticle mass losses are indeed important. Experimental results show that the mass of cathode material removed by the macroparticles flux is greater than the mass of cathode material leaving in form of ions. Besides ion current measurements also used the weighing method to determine the total erosion rate of cathode materials. From the analysis of the erosion rate as a function of charge transferred by the vacuum arc and arc in gases were concluded that the total erosion rate approaches the ion erosion rate if the charge transferred by the arc is small. The dependence of the ion current from vacuum arc current is in linear relation. The approximate independence of arc current is consistent with findings that increasing the arc current leads to an increase in the number of emission centers rather than changing the character of these centers.","PeriodicalId":296641,"journal":{"name":"2016 27th International Symposium on Discharges and Electrical Insulation in Vacuum (ISDEIV)","volume":"10 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122201253","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 : 2016-09-01DOI: 10.1109/DEIV.2016.7764030
P. Kiziridi, G. Ozur, E. Yakovlev
In the paper, the results on the study of the stability of multi-emitter, resistive decoupled, explosive-emission cathodes operation in a high-current, plasma-filled diode are presented. Two types of the cathode were investigated: the cathode based on TBO-1 resistors and the cathode made of Ni-Cr wires. It has been shown that in comparison with traditionally used copper-braid cathodes, the resistive decoupled cathodes allow one to decrease standard deviation of the beam energy density from pulse to pulse as well as the ratio of its maximum value to its average value in series of pulses. The last parameter is of most importance for surface alloying which is very sensitive to deviation of the beam energy density.
{"title":"Improvement the stability of operation of a high-current, plasma-filled electron gun","authors":"P. Kiziridi, G. Ozur, E. Yakovlev","doi":"10.1109/DEIV.2016.7764030","DOIUrl":"https://doi.org/10.1109/DEIV.2016.7764030","url":null,"abstract":"In the paper, the results on the study of the stability of multi-emitter, resistive decoupled, explosive-emission cathodes operation in a high-current, plasma-filled diode are presented. Two types of the cathode were investigated: the cathode based on TBO-1 resistors and the cathode made of Ni-Cr wires. It has been shown that in comparison with traditionally used copper-braid cathodes, the resistive decoupled cathodes allow one to decrease standard deviation of the beam energy density from pulse to pulse as well as the ratio of its maximum value to its average value in series of pulses. The last parameter is of most importance for surface alloying which is very sensitive to deviation of the beam energy density.","PeriodicalId":296641,"journal":{"name":"2016 27th International Symposium on Discharges and Electrical Insulation in Vacuum (ISDEIV)","volume":"32 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122230346","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}
The objective of this paper is to propose a quantitative method to determine opening velocities for VCBs at transmission voltage. A couple of 2/3 coil-type axial magnetic field (AMF) contacts, which are used in a 126 kV vacuum interrupter, are arranged in a demountable vacuum chamber. The movable contact is opening with three different kinds of opening travel-curves. Each curve is adjusted by two opening velocities, v1 and v2, respectively. The v1 is an average opening velocity within 1/3 full contact gap, which is with 1.8 m/s, 2.4 m/s and 2.7 m/s, respectively. The v2 is an average opening velocity within 2/3 full contact gap, which is with 2.4 m/s, 2.7 m/s, and 3.0 m/s, respectively. The test current ranges from 4 kA to 40 kA, stepped by 4 kA. When a VCB is used to interrupt a short-circuit current, the preferred opening velocity is determined by reducing the arcing interval tI for the intense arc mode and increasing the arcing interval tII until the formation of high-current anode mode (HAM). The preferred v1 is higher than a threshold value v1_th, at which there is a peak critical contact gap dI_peak, for the evolving from intense arc mode into diffuse arc mode. The preferred value v2 is lower than another threshold value v2_th, at which there also exists a peak critical contact gap dII_peak, for the evolving from diffuse arc mode into the footpoint mode and anode spot mode.
{"title":"Determination of opening velocities for vacuum circuit breakers at transmission voltage","authors":"X. Yao, Jianhua Wang, Yingsan Geng, Zhiyuan Liu, Xiaoshe Zhai","doi":"10.1109/DEIV.2016.7748703","DOIUrl":"https://doi.org/10.1109/DEIV.2016.7748703","url":null,"abstract":"The objective of this paper is to propose a quantitative method to determine opening velocities for VCBs at transmission voltage. A couple of 2/3 coil-type axial magnetic field (AMF) contacts, which are used in a 126 kV vacuum interrupter, are arranged in a demountable vacuum chamber. The movable contact is opening with three different kinds of opening travel-curves. Each curve is adjusted by two opening velocities, v1 and v2, respectively. The v1 is an average opening velocity within 1/3 full contact gap, which is with 1.8 m/s, 2.4 m/s and 2.7 m/s, respectively. The v2 is an average opening velocity within 2/3 full contact gap, which is with 2.4 m/s, 2.7 m/s, and 3.0 m/s, respectively. The test current ranges from 4 kA to 40 kA, stepped by 4 kA. When a VCB is used to interrupt a short-circuit current, the preferred opening velocity is determined by reducing the arcing interval tI for the intense arc mode and increasing the arcing interval tII until the formation of high-current anode mode (HAM). The preferred v1 is higher than a threshold value v1_th, at which there is a peak critical contact gap dI_peak, for the evolving from intense arc mode into diffuse arc mode. The preferred value v2 is lower than another threshold value v2_th, at which there also exists a peak critical contact gap dII_peak, for the evolving from diffuse arc mode into the footpoint mode and anode spot mode.","PeriodicalId":296641,"journal":{"name":"2016 27th International Symposium on Discharges and Electrical Insulation in Vacuum (ISDEIV)","volume":"23 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123325506","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 : 2016-09-01DOI: 10.1109/DEIV.2016.7748686
Guo-Qiang Su, Baipeng Song, Yi-Bo Wang, H. Mu, Guanjun Zhang
For dielectric-vacuum compound insulation systems, the discharges usually occur across the insulator surface with an onset voltage much lower than the breakdown voltage for vacuum gap of the same length, which is the main cause leading to insulation failure. It has always been a hot topic to improve the surface insulation strength in vacuum. In this paper, the relationship between the flashover time delay and electric field is studied under nanosecond impulse voltage. Experiment results suggest that the flashover time delay was proportional to N-th power of electric field for grooved insulators with different parameters. For grooved insulator, the flashover channel prefer to develop along the grooves rather than pass over the groove wall. The blocking effect of grooves to the electron multiplication in cathode-anode direction leads to the increased time delay. A narrow band of electric field with respect to time delay is formed over the flat samples. The breakdown electric field of a grooved insulator was increased by more than 100% than that of a flat one. The flashover electric field tends to be saturated when the groove depth is more than 2 mm for both PTFE and PMMA, which is correlated with the trajectory of electrons travelling across insulator surface. Grooves near electrode is more effective to increase surface insulation strength than grooves in middle area, which can be of great help to guide the structure optimization in engineering application.
{"title":"Flashover time delay characteristics of grooved insulators under nanosecond pulse voltage in vacuum","authors":"Guo-Qiang Su, Baipeng Song, Yi-Bo Wang, H. Mu, Guanjun Zhang","doi":"10.1109/DEIV.2016.7748686","DOIUrl":"https://doi.org/10.1109/DEIV.2016.7748686","url":null,"abstract":"For dielectric-vacuum compound insulation systems, the discharges usually occur across the insulator surface with an onset voltage much lower than the breakdown voltage for vacuum gap of the same length, which is the main cause leading to insulation failure. It has always been a hot topic to improve the surface insulation strength in vacuum. In this paper, the relationship between the flashover time delay and electric field is studied under nanosecond impulse voltage. Experiment results suggest that the flashover time delay was proportional to N-th power of electric field for grooved insulators with different parameters. For grooved insulator, the flashover channel prefer to develop along the grooves rather than pass over the groove wall. The blocking effect of grooves to the electron multiplication in cathode-anode direction leads to the increased time delay. A narrow band of electric field with respect to time delay is formed over the flat samples. The breakdown electric field of a grooved insulator was increased by more than 100% than that of a flat one. The flashover electric field tends to be saturated when the groove depth is more than 2 mm for both PTFE and PMMA, which is correlated with the trajectory of electrons travelling across insulator surface. Grooves near electrode is more effective to increase surface insulation strength than grooves in middle area, which can be of great help to guide the structure optimization in engineering application.","PeriodicalId":296641,"journal":{"name":"2016 27th International Symposium on Discharges and Electrical Insulation in Vacuum (ISDEIV)","volume":"24 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125550867","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 : 2016-09-01DOI: 10.1109/DEIV.2016.7763984
S. Hildebrandt, G. Wiehl
For vacuum brazing applications Hermetic Sealing Materials (HSM) with low partial pressure are widely used to join copper or stainless steel parts. For joining copper AgCu28 is a widespread material, which is well characterized and investigated. For stainless steel, AgCu28Ge2Co0.3 is commonly used if the same brazing temperature as AgCu28 is required. Umicore Technical Materials has developed a new copper-based HSM. The tensile strength of the stainless steel joints on stainless steel is comparable to AgCu28Ge2Co0.3 and the wettability is significantly improved. In this article, the physical properties of the alloy and its brazed joints will be presented in comparison to AgCu28GeCo0.3. However, today the silver content of HSMs is more in focus than in the past decades, because it has the biggest impact on the material prices. To accommodate this trend the total silver content of the new HSM is reduced by almost 44 %.
{"title":"A new copper based hermetic sealing material: A comparison with AgCu28GeCo0.3","authors":"S. Hildebrandt, G. Wiehl","doi":"10.1109/DEIV.2016.7763984","DOIUrl":"https://doi.org/10.1109/DEIV.2016.7763984","url":null,"abstract":"For vacuum brazing applications Hermetic Sealing Materials (HSM) with low partial pressure are widely used to join copper or stainless steel parts. For joining copper AgCu28 is a widespread material, which is well characterized and investigated. For stainless steel, AgCu28Ge2Co0.3 is commonly used if the same brazing temperature as AgCu28 is required. Umicore Technical Materials has developed a new copper-based HSM. The tensile strength of the stainless steel joints on stainless steel is comparable to AgCu28Ge2Co0.3 and the wettability is significantly improved. In this article, the physical properties of the alloy and its brazed joints will be presented in comparison to AgCu28GeCo0.3. However, today the silver content of HSMs is more in focus than in the past decades, because it has the biggest impact on the material prices. To accommodate this trend the total silver content of the new HSM is reduced by almost 44 %.","PeriodicalId":296641,"journal":{"name":"2016 27th International Symposium on Discharges and Electrical Insulation in Vacuum (ISDEIV)","volume":"33 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131961847","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 : 2016-09-01DOI: 10.1109/DEIV.2016.7748753
Y. Zemskov, I. Muzyukin
A time dependence of in generation during a lifetime of a single cathode spot is of a great importance. To obtain such a dependence it is necessary to investigated vacuum discharge at a threshold current with small size electrode setup. Vacuum arc was feed by capacitor with restrictive resistor. After arc ignition the arc current decreases in time of 300-500ns up to threshold current. When threshold current was achieved there was only single cathode spot operating in a vacuum arc. A small discharge setup was used to obtain nanosecond time resolution on the ion flow measurement. Cathode-anode gap and anode - collector gap was established as 0.1mm. The average time of fly of ions from cathode spot to the collector can be estimated as 10ns. The estimated lifetime of cathode spot on a molybdenum cathode is 20-50ns. Thus the electrode setup built at the present experiments can be used to obtain ion generation dependence during a single cathode spot lifetime. The electron flow time dependence was obtained too. The results obtained make it possible to connect charged particle flow fluctuations with cathode spot life cycle.
{"title":"The experimental investigation of a charged particle flows in a submicrosecond vacuum arc at a threshold current","authors":"Y. Zemskov, I. Muzyukin","doi":"10.1109/DEIV.2016.7748753","DOIUrl":"https://doi.org/10.1109/DEIV.2016.7748753","url":null,"abstract":"A time dependence of in generation during a lifetime of a single cathode spot is of a great importance. To obtain such a dependence it is necessary to investigated vacuum discharge at a threshold current with small size electrode setup. Vacuum arc was feed by capacitor with restrictive resistor. After arc ignition the arc current decreases in time of 300-500ns up to threshold current. When threshold current was achieved there was only single cathode spot operating in a vacuum arc. A small discharge setup was used to obtain nanosecond time resolution on the ion flow measurement. Cathode-anode gap and anode - collector gap was established as 0.1mm. The average time of fly of ions from cathode spot to the collector can be estimated as 10ns. The estimated lifetime of cathode spot on a molybdenum cathode is 20-50ns. Thus the electrode setup built at the present experiments can be used to obtain ion generation dependence during a single cathode spot lifetime. The electron flow time dependence was obtained too. The results obtained make it possible to connect charged particle flow fluctuations with cathode spot life cycle.","PeriodicalId":296641,"journal":{"name":"2016 27th International Symposium on Discharges and Electrical Insulation in Vacuum (ISDEIV)","volume":"62 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116588720","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 : 2016-09-01DOI: 10.1109/DEIV.2016.7748672
S. Lagotzky, H. Schellekens, A. Papillon, G. Muller
A dc field emission scanning microscope (FESM) was used to characterize the electron emission current of CuCr25 sintered contacts. Field emission scans at 20-50 MV/m using a truncated cone anode of 300 μm in diameter localized emitting defects with a positioning accuracy of ~150 μm in the measured area (~25 mm2) of the contact. The strongest activation of emitters was noticed at 30-40 MV/m resulting in 15 emitters at 50 MV/m. Afterwards, the I(E)-characteristic of the 10 dominant emission sites was measured locally. Two different types of emission could be observed: a normal Fowler-Nordheim-like emission where the current depends only on the applied voltage, and an abnormal emission where the current shows a strong hysteresis between the rising voltage branch and the decreasing voltage branch. The abnormal behavior can lead to an emission current increase once a critical electric field is exceeded. Possible surface effects influencing the emission current are either open pores or dielectric inclusions at the grain boundaries. The field emission enhancement factor β of these sites vary from 115 to 300 similar to values reported before. The number density of emitters is well above 0.5/mm2. In sealed vacuum interrupters only one emitter is active at a specific moment in time, shadowing the other emitters.
{"title":"Voltage conditioning effect on CuCr contacts","authors":"S. Lagotzky, H. Schellekens, A. Papillon, G. Muller","doi":"10.1109/DEIV.2016.7748672","DOIUrl":"https://doi.org/10.1109/DEIV.2016.7748672","url":null,"abstract":"A dc field emission scanning microscope (FESM) was used to characterize the electron emission current of CuCr25 sintered contacts. Field emission scans at 20-50 MV/m using a truncated cone anode of 300 μm in diameter localized emitting defects with a positioning accuracy of ~150 μm in the measured area (~25 mm2) of the contact. The strongest activation of emitters was noticed at 30-40 MV/m resulting in 15 emitters at 50 MV/m. Afterwards, the I(E)-characteristic of the 10 dominant emission sites was measured locally. Two different types of emission could be observed: a normal Fowler-Nordheim-like emission where the current depends only on the applied voltage, and an abnormal emission where the current shows a strong hysteresis between the rising voltage branch and the decreasing voltage branch. The abnormal behavior can lead to an emission current increase once a critical electric field is exceeded. Possible surface effects influencing the emission current are either open pores or dielectric inclusions at the grain boundaries. The field emission enhancement factor β of these sites vary from 115 to 300 similar to values reported before. The number density of emitters is well above 0.5/mm2. In sealed vacuum interrupters only one emitter is active at a specific moment in time, shadowing the other emitters.","PeriodicalId":296641,"journal":{"name":"2016 27th International Symposium on Discharges and Electrical Insulation in Vacuum (ISDEIV)","volume":"4 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128285951","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 : 2016-09-01DOI: 10.1109/DEIV.2016.7748681
Yingyao Zhang, Xinye Xu, Lijun Jin, Yewen Zhang
The objective of this paper is to investigate the lightning impulse voltage breakdown characteristics of vacuum interrupters (VIs) with different contact materials experimentally. In the experiments, four 12 kV VIs were investigated. The moving and fixed contact materials were CuW90 and CuCr30. The standard lightning impulse voltages were applied. The results showed that the upper and lower limits of the conditioning processes increased by about 53.5 kV and 15 kV with the contact gap increased from 2 mm to 4 mm. At the same contact gap, the upper and the lower limits of the instantaneous breakdown voltages of the contacts CuW90-to-CuCr30 (cathode-to-anode) were higher than the contacts CuCr30-to-CuW90by about 15 kV. It was also found that there were some large areas of similar melting marks and a large numbers of micro-particles all over the anode contact surface. There were obvious damages distributed all over the cathode contact surface and the features of the damages were dependent on the contact materials.
{"title":"Lightning impulse voltage breakdown characteristics of vacuum interrupters with different contact materials","authors":"Yingyao Zhang, Xinye Xu, Lijun Jin, Yewen Zhang","doi":"10.1109/DEIV.2016.7748681","DOIUrl":"https://doi.org/10.1109/DEIV.2016.7748681","url":null,"abstract":"The objective of this paper is to investigate the lightning impulse voltage breakdown characteristics of vacuum interrupters (VIs) with different contact materials experimentally. In the experiments, four 12 kV VIs were investigated. The moving and fixed contact materials were CuW90 and CuCr30. The standard lightning impulse voltages were applied. The results showed that the upper and lower limits of the conditioning processes increased by about 53.5 kV and 15 kV with the contact gap increased from 2 mm to 4 mm. At the same contact gap, the upper and the lower limits of the instantaneous breakdown voltages of the contacts CuW90-to-CuCr30 (cathode-to-anode) were higher than the contacts CuCr30-to-CuW90by about 15 kV. It was also found that there were some large areas of similar melting marks and a large numbers of micro-particles all over the anode contact surface. There were obvious damages distributed all over the cathode contact surface and the features of the damages were dependent on the contact materials.","PeriodicalId":296641,"journal":{"name":"2016 27th International Symposium on Discharges and Electrical Insulation in Vacuum (ISDEIV)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127607696","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 : 2016-09-01DOI: 10.1109/DEIV.2016.7763952
Qiaosen Wang, Z. Shi, Yingkui Zhang, S. Jia, Lijun Wang
HVDC interruption technique is the bottleneck problem of flexible HVDC project. The HVDC vacuum circuit breaker based on artificial current zero is a feasible and effective method to solve this problem. In this circuit breaker, the parameters of the commutation branch have a vital influence for the breaking process. In this paper, the interruption process for HVDC based on artificial current zero is modeled and simulated. The influence of commutation branch parameters on interruption process is studied. The simulation results under different conditions are analyzed. Based on the analysis, this paper puts forward the reasonable parameters of the commutation branch, which could improve the breaking ability of the circuit breaker.
{"title":"Simulation and analysis of a HVDC vacuum circuit breaker based on artificial current zero","authors":"Qiaosen Wang, Z. Shi, Yingkui Zhang, S. Jia, Lijun Wang","doi":"10.1109/DEIV.2016.7763952","DOIUrl":"https://doi.org/10.1109/DEIV.2016.7763952","url":null,"abstract":"HVDC interruption technique is the bottleneck problem of flexible HVDC project. The HVDC vacuum circuit breaker based on artificial current zero is a feasible and effective method to solve this problem. In this circuit breaker, the parameters of the commutation branch have a vital influence for the breaking process. In this paper, the interruption process for HVDC based on artificial current zero is modeled and simulated. The influence of commutation branch parameters on interruption process is studied. The simulation results under different conditions are analyzed. Based on the analysis, this paper puts forward the reasonable parameters of the commutation branch, which could improve the breaking ability of the circuit breaker.","PeriodicalId":296641,"journal":{"name":"2016 27th International Symposium on Discharges and Electrical Insulation in Vacuum (ISDEIV)","volume":"2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130633295","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 : 2016-09-01DOI: 10.1109/DEIV.2016.7748727
Xiaolong Huang, Lijun Wang, Xiao Zhang, S. Jia, Z. Shi
When the arc current is high, the heat flux density injecting into anode will be large and lead to the higher anode temperature, driving the evaporated atoms into arc column. In this paper, the MHD model of vacuum arc considering ionization and recombination of anode vapor is built. The influence of the anode vapor and the micro processes on the arc column is obtained. In the model, the mass, momentum and energy exchange are considered. Additionally, the influence of ionization and recombination process on the electromagnetic process of VA is also considered. In the simulation results, the anode vapor, cathode plasma and VA distribution are all obtained. When the anode temperature is high enough, the anode neutral vapor will enter into arc column, and the strong ionization happens at the interface of anode vapor and cathode plasma. The anode neutral vapor has obviously cooling effect on the arc column. Whether the anode neutral vapor will enter into the arc column or not, is related to the balance between the anode neutral vapor and the cathode plasma.
{"title":"Numerical simulation of HCVA with considering the micro process of anode vapor","authors":"Xiaolong Huang, Lijun Wang, Xiao Zhang, S. Jia, Z. Shi","doi":"10.1109/DEIV.2016.7748727","DOIUrl":"https://doi.org/10.1109/DEIV.2016.7748727","url":null,"abstract":"When the arc current is high, the heat flux density injecting into anode will be large and lead to the higher anode temperature, driving the evaporated atoms into arc column. In this paper, the MHD model of vacuum arc considering ionization and recombination of anode vapor is built. The influence of the anode vapor and the micro processes on the arc column is obtained. In the model, the mass, momentum and energy exchange are considered. Additionally, the influence of ionization and recombination process on the electromagnetic process of VA is also considered. In the simulation results, the anode vapor, cathode plasma and VA distribution are all obtained. When the anode temperature is high enough, the anode neutral vapor will enter into arc column, and the strong ionization happens at the interface of anode vapor and cathode plasma. The anode neutral vapor has obviously cooling effect on the arc column. Whether the anode neutral vapor will enter into the arc column or not, is related to the balance between the anode neutral vapor and the cathode plasma.","PeriodicalId":296641,"journal":{"name":"2016 27th International Symposium on Discharges and Electrical Insulation in Vacuum (ISDEIV)","volume":"10 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130796982","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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