多阴极斑点真空电弧均匀分布时的纵向磁场  

Axial Magnetic Field Distribution Keeping Multi-Cathode Spot Vacuum Arc uniform

作　　者：刘志远[1] 王季梅[1] 王政[1] 王仲奕[1] 苑舜 

机构地区：[1]西安交通大学电气工程学院,710049 [2]东北电力科学研究院,110006

出　　处：《电工技术学报》2000年第4期80-83,共4页Transactions of China Electrotechnical Society

摘　　要：从真空电弧的稳态磁流体动力学方程出发 ,对多阴极斑点的大电流真空电弧均匀分布时的纵向磁场进行分析 ,得到真空电弧在电极表面上均匀分布 ,即形态为与电极同直径的直圆柱时的纵向磁场与半径的关系为Bzopt=qr2 +c (q与c为系数 )。并由此提出了临界半径的概念 ,临界半径R0c是当纵向磁场沿径向均匀分布时电弧也均匀分布的电极半径。电极半径超过R0c时纵向磁场沿径向分布递减可使电弧均匀分布 ,电极半径小于临界半径时纵向磁场沿径向递增可使电弧均匀分布。此结果可以为真空灭弧室小型化提供思路和理论依据。Axial magnetic field (AMF) distribution which keeps multicathode-spot vacuum arc uniform in electrode gap space and contact surfaces is analyzed.The function between the AMF intensity and electrode radius should be B z opt =qr 2+c ( q and c is constant in a certain case), which is the optimum distribution. A new concept called critical radius is given.It is the electrode radius along which vacuum arc distributes uniformly when AMF distributes uniformly too. When electrode radius is greater than critical radius,the AMF should decrease along electrode radius in order to make the arc uniform.On the contrast,when electrode radius is shorter than critical radius,the AMF should increase along electrode radius.These results are helpful to make vacuum interrupter size reduce.

关 键 词：真空电弧 纵向磁场 数学模型 阴极斑点 

分 类 号：TM501.2[电气工程—电器]