The Effects of SF_6-Cu Mixture on the Arc Characteristics in a Medium Voltage Puffer Gas Circuit Breaker due to Variation of Thermodynamic Properties and Transport Coefficients  

作　　者：Vahid ABBASI Ahmad GHOLAMI Kaveh NIAYESH 

机构地区：[1]Electrical Engineering Department,Iran University of Science and Technology,Narmak,Tehran,Iran [2]School of Electical and Computer Engineering,College of Engineering,University of Tehran,IR-14395 Tehran,Iran

出　　处：《Plasma Science and Technology》2013年第6期586-592,共7页等离子体科学和技术（英文版）

摘　　要：In a gas circuit breaker,metal vapor resulting from electrode erosion is injected into the arc plasma.The arc then burns in a mixture of SF;and electrode vapor,which has properties significantly different from those of pure SF;.Thermodynamic properties and transport coefficients of thermal plasmas formed in SF;-copper vapor mixtures change as a function of temperature and pressure.The property that is mostly affected by the presence of copper is electrical conductivity,which is important in magnetohydrodynamic（MHD） analysis.In this study,the transport coefficients of SF;in the presence of 10 percent copper are considered as the basis of MHD simulation.Comparisons are made between the results during arc formation for pure SF;and SF;-Cu mixture in a medium voltage（MV） circuit breaker.According to the transport coefficients influenced by the SF;-Cu mixture,the distribution of the electric potential, temperature,electromagnetic force density and current density of the arc column are presented and discussed.Also,the arc stability and pinch effect near current zero with 3-D simulation are investigated,which is advantageous to improving the efficiency of arc plasma simulation.In a gas circuit breaker,metal vapor resulting from electrode erosion is injected into the arc plasma.The arc then burns in a mixture of SF6 and electrode vapor,which has properties significantly different from those of pure SF6.Thermodynamic properties and transport coefficients of thermal plasmas formed in SF6-copper vapor mixtures change as a function of temperature and pressure.The property that is mostly affected by the presence of copper is electrical conductivity,which is important in magnetohydrodynamic（MHD） analysis.In this study,the transport coefficients of SF6 in the presence of 10 percent copper are considered as the basis of MHD simulation.Comparisons are made between the results during arc formation for pure SF6 and SF6-Cu mixture in a medium voltage（MV） circuit breaker.According to the transport coefficients influenced by the SF6-Cu mixture,the distribution of the electric potential, temperature,electromagnetic force density and current density of the arc column are presented and discussed.Also,the arc stability and pinch effect near current zero with 3-D simulation are investigated,which is advantageous to improving the efficiency of arc plasma simulation.

关 键 词：magnetohydrodynamic（MHD） electromagnetic force SF6-Cu mixture transport coefficients pure SF6 

分 类 号：TM561[电气工程—电器]