摘要
利用长间隙放电3维仿真模型对实际的放电现象进行机理分析、放电特性预测与绝缘设计评价具有指导意义。因此在流注-先导系统起始和动态发展的物理机制基础上,分析了初始电晕起始与流注发展的基本物理过程,推导了基于模拟电荷法与电位畸变法的流注空间电荷增量对电位畸变贡献的计算方法,建立了基于热电离理论的流注-先导转化模型,并利用电介质击穿模型（DBM）模型将2维模型外延至3维空间,从而完成了对长间隙放电正极性流注-先导发展全过程的3维仿真模型构建。利用该模型进行仿真获得的先导平均轴向速度为1.58～1.62cm/μs,空间电荷电位畸变系数KQ的平均值介于3.8×10-11～4.4×10-11 C/（V m）之间,并得到了不同间隙长度下击穿电压与先导发展过程等的变化规律,与长间隙放电试验综合同步观测平台在平均轴向速度、末跃高度等方面所获得的试验数据较为符合,证明了模型在3 m棒-板间隙下模拟正极性流注-先导发展方面的适用性。
The application of the 3-D simulation model is of directive significance for analyzing discharge mechanism, predicting discharge property, and evaluating insulation designs are of important directive significance. On the basis of the origination and the dynamic development mechanism of the streamer-leader system, we analyzed the fundamental physi- cal processes of the first corona origination and the streamer development, and derived a calculation method of the electric potential distortion caused by the increment of streamer-space charge by the charge simulation method and the potential distortion method. Then we established a streamer-leader transformation model based on the thermal ionization theory. Finally, we used the dielectric breakdown model （DBM） to extend the 2-D streamer-leader transformation model to 3-D, and consequently established an integral process simulation model of long-gap discharge. According to the simu- lations with the model, the average velocity of the leader＇s axial propagation is 1.58-1.62 cm/μs, and the voltage distortion coefficient of the space charge is within 3.8×10-11--4.4×10-11 C/（V.m）. Together with the breakdown voltage and the leader development, the results of the simulations are in accordance with those acquired through long gap dis- charge integrated synchronous observation platform in aspects of the average axial velocity, the final jump height etc., which confirms the applicability of the model in the scale.
出处
《高电压技术》
EI
CAS
CSCD
北大核心
2014年第9期2903-2910,共8页
High Voltage Engineering
基金
国家重点基础研究发展计划(973计划)(2011CB209405)
国家电网公司科技项目(编号略)~~
关键词
长间隙放电
流注
先导
模拟电荷法
热电离
电位畸变
long gap discharge
streamer
leader
charge simulation method
thermal ionization
potential distortion
