阶跃电压下液体电介质击穿过程数值分析  

Numerical Analysis of Liquid Dielectric Breakdown Process Applied in Step Voltage

作　　者：王正伟[1] 赵大伟[1] 杨嘉祥[1] 郑殿春[1] 杨韦国 陈楠[1] 王佳[1] 

机构地区：[1]哈尔滨理工大学电气与电子工程学院,黑龙江哈尔滨150080

出　　处：《哈尔滨理工大学学报》2014年第3期80-83,共4页Journal of Harbin University of Science and Technology

基　　金：黑龙江省教育厅科学技术研究重点项目(12511Z008)

摘　　要：以变压器油作为研究对象,采用有限元方法对针-球电极下建立的用于表述液体电介质流注预放电过程中载流子的产生及输运特性的偏微分方程进行求解分析,获得阶跃电压下变压器油隙预放电过程空间电荷动力学特性.数值模拟结果表明,液体介质击穿的根本原因是油隙中自由载流子的产生、迁移形成了预击穿电流,由此产生的焦耳热使得油隙中温度升高,促进流注发展.根据这些现象得出的结论能够很容易理解液体电介质的击穿机理,有利于液体电介质在电力系统领域得到更合理的应用.The transformer oil was taken as the object of study in this paper,and the finite element method（FEM） was employed to analyze and solve the partial differential equations（PDE） which was built under needlesphere electrode for describing the generation and transport properties of free charge carriers,and then the dynamics characteristics of space charges in the liquid-gap pre-discharge process under step voltages were gained.According to the simulating results,the fundamental causes of the dielectric liquids breakdown are described as follows,the pre-breakdown current is firstly formed by the generation and migration of the charge carriers in the oil gap,and then the joule heat generated from it makes temperature rise along the oil-gap.Meanwhile,the streamer is continuously evolving in the liquid.Then these conclusions enable people to easily understand breakdown mechanism of the liquid dielectrics that are reasonably applied to power system fields.

关 键 词：变压器油 数值模拟 空间电荷 流注 

分 类 号：TM214[一般工业技术—材料科学与工程]