外加准轴向磁场POS断路过程的粒子模拟  

Particle simulation of opening process in plasma opening switch by applying external quasi-axial magnetic field

作　　者：王晓明[1] 赵莹[2] 刘璐[1] 刘宏[3] 

机构地区：[1]哈尔滨工业大学电气工程系,黑龙江哈尔滨150001 [2]中国科学院电工研究所,北京100190 [3]哈尔滨工业大学机器人研究所,黑龙江哈尔滨150001

出　　处：《电机与控制学报》2009年第5期654-659,共6页Electric Machines and Control

基　　金：航天科技创新基金(天科研2001181-19);哈尔滨工业大学跨学科交叉性研究基金(HIT.MD2002.1)

摘　　要：为了研究外加准轴向磁场同轴内阴极结构等离子体断路开关(POS)的工作特性,采用单元粒子方法对激磁线圈分别放置在内阴极内侧和外阳极外侧的POS断路过程进行研究,模拟分析POS中电场和磁场的时空变化、等离子体电子的动力学行为和特性,重点研究内阴极结构POS的断路过程。结果表明:激磁线圈置于内阴极内侧时,极间磁场为线圈外磁场,在开关区的矢量磁密变化曲率大,有较大径向分量且中心区域值较两侧为小,这种外加磁场对POS的断路过程影响较小;激磁线圈置于外阳极外侧时,极间磁场为线圈内磁场,在开关区的均匀性较好,该准轴向磁场改变了电子运动的轨迹,也改变了原角向磁场的分布,更容易实现POS的断路,实现较高幅值的断路电压,并且电流损失较小,POS的断路效率较高;准轴向磁场和自角向磁场的共同作用使等离子体电子作向下游扩散的锥体螺旋运动。In this paper, the opening process of plasma opening switch （POS） with different magnetic coil positions, placed inside the cathode or outside the anode, is investigated systematically by using particlein-cell（PIC） simulation method, in order to study the ner cathode in external quasi-axial magnetic field. The kinetic behavior of electrons in the plasma area of the operation characteristic of the coaxial POS with inspace-time change of electromagnetic field and the POS had been simulated, and the opening process of the inner-cathode POS had been specially studied. The result indicates that when the coil is placed inside the cathode, the curvature and radial component of vector magnetic intensity in switching area are bigger and the radial component is smaller in the center, so the influence on opening process of this coil magnetic field is small. When the coil is placed outside the anode, the magnetic field in the switching atea has good uniformity and the original distributing of the angular magnetic field is changed, so the movement trajectory of electrons in the POS switch area is changed. It is easier to achieve the opening of the POS, so the amplitude of opening voltage is higher and the current loss of the POS is smaller. The common role of the quasixial and self-angular magnetic field make electrons of the plasma expand to the downstream in cone-shaped helix form.

关 键 词：等离子体断路开关 断路过程 准轴向磁场 单元粒子 

分 类 号：TM8[电气工程—高电压与绝缘技术] TN248[电子电信—物理电子学]