同轴电极的负电晕特里切尔脉冲特性分析  

Characteristics of Negative Corona Trichel Pulses in a Coaxial Electrode System

作　　者：何旺龄[1] 何俊佳[1] 张锦[2] 万保权[2] 

机构地区：[1]华中科技大学电气与电子工程学院,武汉430074 [2]中国电力科学研究院(武汉),武汉430074

出　　处：《电工技术学报》2016年第11期211-218,共8页Transactions of China Electrotechnical Society

基　　金：国家重点基础研究发展(973)计划资助项目(2011CB209402)

摘　　要：利用流体动力学模型,对大气压条件下空气间隙的同轴电极结构进行了负极性电晕放电特性研究,获得了一组规则的特里切尔脉冲。除第一个脉冲外,其他脉冲的幅值均在1.5-2.5 m A。然后,对第一个脉冲（称为第一脉冲）不同发展阶段的空间电场分布和粒子密度分布进行了描述,并讨论了第一脉冲与第二脉冲之间的死区时间内不同时刻负离子密度的变化过程及其对阴极表面电场的影响作用,最后,对第二脉冲发展前后空间电场分布、电子密度分布和负离子密度分布及其变化规律进行了进一步的描述。仿真表明,随着负离子在电场力的作用下逐渐向外迁移,导线表面电场强度开始恢复,但其恢复速度在负离子远离导线的过程中逐渐变缓。同时,当导线表面电场强度恢复至低于初始拉普拉斯场强的某一特定值时,新的脉冲就开始发生,第二脉冲发生时空间电场、电子密度及负离子密度的最大值均小于第一脉冲。In this paper,the characteristics of negative corona discharge in air at atmospheric pressure are studied by using the hydrodynamic drift-diffusion model with a coaxial electrode system,and a set of regular Trichel pulses is obtained. It is found that the pulse amplitude is between 1. 5 m A and 2. 5 m A except the first one. Then the distributions of the electric field,the ion densities at different stages during the first pulse are plotted. The distribution of the negative ion density and its influence on the conductor surface electric field are discussed during the dead time between the first pulse and the second pulse. After that,the distributions of the electric field,the electron and negative ion densities around the second pulse are plotted. The simulation results show that the electric field at the conductor surface increases when the negative ions remove from cathode under the influence of electric field force; and the recovery velocity of electric field slows down when the negative ions move away. Besides,before the electric field at the conductor surface recovers to its original Laplacian field strength,the next new pulse begins to happen. It is also found that the maximum values of the electric field,the electron and negative ion densities are reduced during the second pulse comparing with those in the first pulse.

关 键 词：负电晕 特里切尔脉冲 空间电场分布 粒子密度 

分 类 号：TM723[电气工程—电力系统及自动化]